,transcriber's note3 ,a few typographical errors have been corrected3 they are listed at the end of the text4 99 99 99 99 99 ,illustration3 ,,the ,,viscera ,,in ,,position4 99 99 99 99 99 ,a ,,treatise ,,on ,,physiology ,,and ,,hygiene ,,for ,,educational ,,institutions ,,and ,,general ,,readers4 ,,fully ,,illustrated4 ,,by ,,joseph ,c4 ,,hutchison1 ,m4 ,d41 ,president of the ,new ,york ,pathological ,society1 ,vice-,president of the ,new ,york ,academy of ,medicine1 ,surgeon to the ,brooklyn ,city ,hospital1 late ,president of the ,medical ,society of the ,state of ,new ,york1 etc4 99 99 99 99 99 ,,new ,,york3 ,,clark ,,maynard1 ,,publishers1 #e ,,barclay ,,street4 #ahgb4 99 99 99 99 99 ,entered according to ,act of ,congress1 in the year #ahgj1 ,by ,,clark ,,maynard4 ,in the ,office of the ,librarian of ,congress1 at ,washington4 ,stereotyped by ,,little1 ,,rennie ,,co4 #fde and #fdg ,broadway4 99 99 99 99 99 ,,to ,,my ,,wife1 ,,whose ,,sympathy ,,has1 ,,for ,,more ,,than ,,twenty ,,years1 ,,lightened ,,the ,,cares ,,incident ,,to ,,an ,,active ,,professional ,,life1 ,,this ,,humble ,,volume ,,is ,,affectionately ,,inscribed4 99 99 99 99 99 #c ,,preface4 ------o------ ,this work is designed to present the leading facts and principles of human ,physiology and ,hygiene in clear and concise language1 so that pupils in schools and colleges1 and readers not familiar with the subjects1 may readily comprehend them4 ,anatomy1 or a description of the structure of an organ1 is of course necessary to the understanding of its ,physiology1 or its uses4 ,enough of the former study has1 therefore1 been introduced1 to enable the pupil to enter intelligently upon the latter4 ,familiar language1 as far as practicable1 has been employed1 rather than that of a technical character4 ,with a view1 however1 to supply what might seem to some a deficiency in this regard1 a ,pronouncing ,glossary has been added1 which will enable the inquirer to understand the meaning of many scientific terms not in common use4 ,in the preparation of the work the writer has carefully examined all the best material at his command1 and freely used it2 the special object being to have it abreast of the present knowledge on the subjects treated1 as far as such is possible in a work so elementary as this4 ,the discussion of disputed points has been avoided1 it being manifestly inappropriate in a work of this kind4 ,instruction in the rudiments of ,physiology in schools does not necessitate the general practice of dissections1 or of experiments upon animals4 ,the most important subjects may be illustrated by #d drawings1 such as are contained in this work4 ,models1 especially those constructed by ,,auzoux of ,paris1 dried preparations of the human body1 and the organs of the lower animals1 may also be used with advantage4 ,the writer desires to acknowledge his indebtedness to ,r4 ,m4 ,,wyckoff1 ,m4,d41 for valuable aid in the preparation of the manuscript for the press2 and to ,r4 ,,cresson ,,stiles1 ,m4,d41 a skilful microscopist and physician1 for the chapter ,on the ,use of the ,microscope in the ,study of ,physiology4 ,mr4 ,,avon ,c4 ,,burnham1 the well-known teacher of gymnastics1 furnished the drawing of the parlor gymnasium and the directions for its use4 ,brooklyn1 ,n4 ,y41 #ahgj4 99 99 99 99 99 #e ,,contents4 ,,chapter ,i4 ,,page ,,the ,,framework ,,of ,,the ,,body #ae ,the ,bones--,their form and composition--,the ,properties of ,bone--,the ,skeleton--,the ,joints--,the ,spinal ,column--,the ,growth of ,bone--,the ,repair of ,bone4 ,,chapter ,,ii4 ,,the ,,muscles #be ,the ,muscles--,flexion and ,extension--,the ,tendons--,contraction--,physical ,strength--,necessity for ,exercise--,its ,effects--,forms of ,exercise--,walking--,riding--,gymnastic s--,open-air ,exercise--,sleep-- ,recreation4 ,,chapter ,,iii4 ,,the ,,integument1 ,,or ,,skin #da ,the ,integument--,its ,structure--,the ,nails and ,hair--,the ,complexion--,the ,sebaceous ,glands--,the ,perspiratory ,glands--,perspiration and its uses--,importance of ,bathing--,different kinds of ,baths--,manner of ,bathing--,the ,benefits of the ,sun--,importance of ,warm ,clothing--,poisonous ,cosmetics4 ,,chapter ,,iv4 ,,the ,,chemistry ,,of ,,food #ec ,the ,source of ,food--,inorganic ,substances--,water--,salt--,lime--,iron -- ,organic ,substances--,albumen1 ,fibrin1 and ,casein--,the ,fats or ,oils--,the ,sugars1 ,starch1 and ,gum--,stimulating ,substances--,necessity of a ,regulated ,diet4 #f ,,chapter ,v4 ,,food ,,and ,,drink #fd ,necessity for ,food--,waste and ,repair--,hunger and ,thirst--,amount of ,food--,renovation of the ,body--,mixed ,diet--,milk--,eggs--,meat--,cooking --,vegetable ,food--,bread--,the ,potato--,fruits--,purity of ,water--,action of ,water upon ,lead--,coffee1 ,tea1 and ,chocolate--,effects of ,alcohol4 ,,chapter ,,vi4 ,,digestion #hj ,the ,principal ,processes of ,nutrition--,the ,general ,plan of ,digestion-- ,mastication--,the ,teeth--,preservation of the ,teeth--,insalivation--,the ,stomach and the ,gastric ,juice--,the ,movements of the ,stomach--,gastric ,digestion--,the ,intestines--,the ,bile and ,pancreatic ,juice--,intestinal ,digestion--,absorption by means of ,blood-vessels and ,lacteals--,the ,lymphatic or ,absorbent ,system--,the ,lymph--,conditions which affect ,digestion--,the ,quality1 ,quantity1 and ,temperature of the ,food--,the ,influence of ,exercise and ,sleep4 ,,chapter ,,vii4 ,,the ,,circulation #aja ,the ,blood--,its ,plasma and ,corpuscles--,coagulation of the ,blood--,the ,uses of the ,blood--,transfusion--,change of ,color--,the ,organs of the ,circulation--,the ,heart1 ,arteries1 and ,veins--,the ,cavities and ,valves of the ,heart--,its ,vital ,energy--,passage of the ,blood through the ,heart--,the ,frequency and ,activity of its ,movements--,the ,pulse--,the ,sphygmograph--,the ,capillary ,blood-vessels--,the ,rate of the ,circulation--,assimilation--,injuries to the ,blood-vessels4 ,,chapter ,,viii4 ,,respiration #abc ,the ,objects of ,respiration--,the ,lungs--,the ,air-,passages--,the ,movements of ,respiration--,expiration and ,inspiration--,the ,frequency of ,respiration--,capacity of the ,lungs--,the ,air we ,breathe--,changes in the ,air from ,respiration--,changes in the ,blood--,interchange of ,gases in the ,lungs--,comparison between ,arterial and #g ,venous ,blood--,respiratory ,labor--,impurities of the ,air--,dust--,carbonic ,acid--,effects of ,impure ,air--,nature's ,provision for ,purifying the ,air--,ventilation--,animal ,heat4 ,,chapter ,,ix4 ,,the ,,nervous ,,system #adh ,animal and ,vegetative ,functions--,sensation1 ,motion1 and ,volition--,the ,structure of the ,nervous ,system--,the ,white and ,gray ,substances--,the ,brain--,its ,convolutions--,cerebellum--,the ,spinal ,cord and its ,system of ,nerves--,the ,anterior and ,posterior ,roots--,the ,sympathetic ,system of ,nerves--,the ,properties of ,nervous ,tissue--,excitability of ,nervous ,tissues--,the ,functions of the ,spinal ,nerves and ,cord--,the ,direction of the ,fibres of the ,cord--,reflex ,activity and its ,uses--,the ,functions of the ,medulla ,oblongata and the ,cranial ,ganglia--,the ,reflex ,action of the ,brain4 ,,chapter ,x4 ,,the ,,special ,,senses #agg ,the ,production of ,sensations--,variety of ,sensations--,general ,sensibility--,pain and its ,function--,special ,sensation1 ,touch1 ,taste1 ,smell1 ,sight1 and ,hearing--,the ,hand1 the ,organ of ,touch--,the ,sense of ,touch--,delicacy of ,touch--,sensation of ,temperature and ,weight--,the ,tongue the ,organ of ,taste--,the ,nerves of ,taste--,the ,sense of ,taste1 and its ,relations with the other ,senses--,the ,influence of ,education on the ,taste--,the ,nasal ,cavities1 or the ,organs of ,smell--,the ,olfactory ,nerve--,the ,uses of the ,sense of ,smell--,the ,sense of ,sight--,light--,the ,optic ,nerve--,the ,eyeball and its ,coverings--,the ,function of the ,iris--,the ,sclerotic1 ,choroid1 and ,retina--,the ,tears and their ,function--,the ,movements of the ,eyeball--,the ,function of ,accommodation--,the ,sense of ,hearing and ,sound--,the ,ear1 or the organ of ,hearing--,the ,external1 ,middle1 and ,internal ,ear4 ,,chapter ,,xi4 ,,the ,,voice #bbg ,voice and ,speech--,the ,larynx1 or the ,organ of the ,voice--,the ,vocal ,cords--,the ,laryngoscope--,the ,production of the ,voice--,the ,use of the ,tongue--,the different ,varieties of ,voice--,the ,change of ,voice--,its ,compass--,purity of ,tone--,ventriloquy4 #h ,,chapter ,,xii4 ,,the ,,use ,,of ,,the ,,microscope ,,in ,,the ,,study ,,of ,,physiology #bcf ,the ,law of ,tissues--,necessity of the ,microscope--,different kinds of ,microscopes--,additional ,apparatus--,preliminary ,studies--,the ,study of ,human ,tissues--,tissues of the ,inferior ,animals--,incentives to ,study4 ,,appendix4 ,,poisons ,,and ,,their ,,antidotes #bdg ,,glossary #beb #i ,,list ,,of ,,illustrations ,,fig4 ,,page ,,frontispiece1 ,,viscera ,,in ,,position1 #a4 ,section of bone1 #ag #b4 ,structure of bone1 magnified1 #ag #c4 ,the skeleton1 #ah #d4 ,cells of cartilage1 #bj #e4 ,elbow-joint1 #ba #f4 ,spinal column1 #bb #g4 ,the muscles1 #bd #h4 ,muscular tissue1 magnified1 #be #i4 ,biceps muscle of the arm1 #bf #aj4 ,view of knee-joint1 #bg #aa4 ,appliance for strengthening the muscles1 #ce #ab4 ,appliance for strengthening the muscles1 #ce #ac4 ,parlor gymnasium1 #cf #ad4 ,root and transverse section of hair1 magnified1 #dc #ae4 ,granules of potato starch1 #fa #af4 ,section of the trunk1 #ha #ag4 ,section of a tooth1 #hb #ah4 ,section of the jaws1 #hb #ai4 ,section of the jaws--right side1 #hd #bj4 ,structure of a salivary gland1 #hg #ba4 ,head of a horse1 showing salivary gland1 etc4 #hg #bb4 ,section of chest and abdomen1 #ij #bc4 ,organs of digestion1 #ia #bd4 ,the lacteals1 #ig #be4 ,blood corpuscles1 #ajb #bf4 ,blood corpuscles of man and lower animals1 #ajc #bg4 ,circulation of the blood1 #ajh #aj #bh4 ,heart and large vessels1 #aji #bi4 ,section of the heart1 #aaj #cj4 ,form of the pulse1 #aaf #ca4 ,valves of the veins1 #aag #cb4 ,web of frog's foot1 magnified1 #aai #cc4 ,circulation in a frog's foot1 #aai #cd4 ,organs of the chest1 #abd #ce4 ,larynx1 trachea1 and bronchial tubes1 #abe #cf4 ,diagram of the structure of the air-cells1 #abe #cg4 ,section of the lungs1 #abf #ch4 ,section of mouth and throat1 #abg #ci4 ,ciliated cells1 #abh #dj4 ,cerebro-spinal system1 #aea #da4 ,upper surface of the cerebrum1 #aec #db4 ,vertical section of the brain1 #aed #dc4 ,base of the brain1 #aee #dd4 ,brain and spinal cord1 #aef #de4 ,sense of touch1 #ahe #df4 ,section of nasal cavity1 #aic #dg4 ,front view of the eye1 #bjj #dh4 ,vertical section of eye1 #bjb #di4 ,diagram for blind point of eye1 #bjg #ej4 ,retinal image1 #baj #ea4 ,different shapes of the globe of the eye1 #bab #eb4 ,function of accommodation1 #bad #ec4 ,diagram of the ear1 #bah #ed4 ,section of the ear1 #bba #ee4 ,section of larynx and trachea1 #bbi #ef4 ,view of vocal cords by the laryngoscope1 #bcb #eg4 ,different positions of vocal cords1 #bcb #eh4 ,simple microscope1 #bch #ei4 ,compound microscope1 #bci #fj4 ,household microscope1 #bdj #fa4 ,popular microscope1 #bda #aa ,,introduction4 ------o------ ,the ,human ,body is the abode of an immortal spirit1 and is the most complete and perfect specimen of the ,creator's handiwork4 ,to examine its structure1 to ascertain the uses and modes of action of its various parts1 how to protect it from injury1 and maintain it in a healthy condition1 is the design of this work4 ,the departments of knowledge which are concerned in these investigations1 are the science of ,human ,physiology and the art of ,hygiene4 ,,physiology treats of the vital actions and uses of the various parts of living bodies1 whether vegetable or animal4 ,every living thing1 therefore1 has a ,physiology4 ,we have a ,vegetable ,physiology1 which relates to plants2 and an ,animal ,physiology1 relating to the animal kingdom4 ,the latter is also divided into ,comparative ,physiology1 which treats of the inferior races of animals1 and ,human ,physiology1 which teaches the uses of the various parts of the human body4 ,,hygiene1 or the art of preserving health1 is the practical use of ,physiology4 ,it teaches us how to cultivate our bodily and mental powers1 so as to increase our strength and to fit us for a higher enjoyment of life4 ,it also shows us how to prevent some of the accidents which may befall the body1 and to avoid disease4 ,it is proper that we should #ab understand the construction and powers of our bodies2 but it is our duty1 as rational beings1 to know the laws by which health and strength may be maintained and disease warded off4 ,there are various means by which we gain important information respecting the ,physiology of man4 ,plants aid us in understanding the minute structure of the human body1 its circulation1 and absorption4 ,from inferior animals we learn much in respect to the workings of the different organs1 as we call those parts of the system which have a particular duty to perform4 ,in one of them1 as in the foot of the frog1 we can study the circulation of the blood2 in another1 we can study the action of the brain4 ,by vivisection1 or the laying bare of some organ of a living animal1 we are able to investigate certain vital processes which are too deeply hidden in the human body to be studied directly4 ,this is not necessarily a cruel procedure1 as we can1 by the use of ansthetics1 so blunt the sensibility of the animal under operation1 that he need not suffer while the experiment is being performed4 ,there are other means by which we gather our information4 ,there are occasionally men1 who1 from some accident1 present certain parts1 naturally out of view1 in exposed positions4 ,in these cases1 our knowledge is of much greater value than when obtained from creatures lower in the scale of being than man4 ,we are greatly aided1 also1 by the use of various instruments of modern invention4 ,chief among these is the microscope1 which is1 as we shall learn hereafter1 an arrangement and combination of lenses in such a way as greatly to magnify the objects we wish to examine4 #ac ,we have much to say of ,life1 or vital activity1 in the course of our study of ,physiology2 but the most that we know of it is seen in its results4 ,what ,life is1 or where its precise position is1 we are not able to determine4 ,we discover one thing1 however1 that all the parts of the body are united together with wonderful sympathy1 so that one part cannot be injured and other parts not suffer damage4 ,it is further evident that all organs are not equally important in carrying on the work of ,life2 for some may temporarily suspend their action1 without serious results to the system1 while others must never cease from acting4 ,yet there is nothing superfluous or without aim in our frames1 and no part or organ can suffer harm without actual loss to the general bodily health4 ,on this point ,science and ,holy ,writ strictly agree4 99 99 99 99 99 #ad #ae ,,physiology1 ,,and ,,hygiene4 ,,chapter ,i4 ,,the ,,framework ,,of ,,the ,,body4 ,the ,bones--,their ,form and ,composition--,the ,properties of ,bone--,the ,skeleton--,the ,joints--,the ,spinal ,column--,the ,growth of ,bone--,the ,repair of ,bone4 ,sidenote3 #a4 ,the framework of the body8 ,the superstructure8 ,softness and delicacy of the organs8 ,how protected8 #a4 ,,the ,,bones4--,the framework which sustains the human body is composed of the ,bones4 ,the superstructure consists of the various organs on which the processes of life depend4 ,these organs are soft and delicately formed1 and1 if unprotected1 would1 in most cases1 rapidly be destroyed when subjected to violence1 however slight4 ,the bones1 having great strength and power of resistance1 afford the protection required4 ,sidenote3 #b4 ,the more delicate the organ8 ,example in relation to the brain8 ,the eye8 ,the lungs8 ,the services performed by the bones8 #b4 ,the more delicate the organ1 the more completely does ,nature shield it4 ,for example3 the brain1 which is soft in structure1 is enclosed on all sides by a complete box of bone2 the eye1 though it must be near the surface of the body to command an extensive view1 is sheltered from injury within a deep recess of bone2 the lungs1 requiring freedom of motion as well as protection1 are surrounded by a large case of bone and muscle4 ,the bones serve other useful purposes4 ,they give permanence of form to the body1 by #af holding the softer parts in their proper places4 ,they assist in movement1 by affording points of attachment to those organs which have power of motion--the muscles4 ,sidenote3 #c4 ,their shape and size8 ,of what composed8 ,possibility of being separated8 ,effect of fire8 ,of dilute acid8 #c4 ,,the ,,form ,,and ,,composition ,,of ,,the ,,bones4--,their shape and size vary greatly in different parts of the body1 but generally they are arranged in pairs1 one bone for each side of the body4 ,they are composed of both mineral and animal substances1 united in the proportion of two parts of the former to one of the latter2 and we may separate each of these substances from the other for examination4 ,first1 if we expose a bone to the action of fire1 the animal substance is driven off1 or burned out4 ,we now find that1 though the shape of the bone is perfectly retained1 what is left is no longer tough1 and does not sustain weight as before4 ,again1 we may remove the mineral portion1 which is a form of lime1 by placing a bone into a dilute acid4 ,the lime will be dissolved out1 and the shape of the bone remain as before2 but now its firmness has disappeared1 and it may be bent without breaking4 ,sidenote3 #d4 ,effect of deficiency of ingredient8 ,usefulness of the lime8 ,of the animal substance8 ,effect of their union8 ,condition1 in youth8 ,old age8 #d4 ,if1 for any reason1 either of these ingredients is disproportionate in the bone during life1 the body is in danger4 ,the lime is useful in giving rigidity of form1 while the animal substance insures toughness and elasticity4 ,by their union1 we are able to withstand greater shocks and heavier falls than would be possible with either alone4 ,in youth1 the period of greatest activity1 the animal constituent is in excess3 a bone then does not break so readily1 but1 when broken1 unites with great rapidity and strength4 ,on the other hand1 the bones of old persons are more easily broken1 and in some cases fail to unite4 ,the mineral matter being then in excess1 indicates that the period of active exertion is drawing to a close4 #ag ,illustration3 ,,fig4 #a4--,,section ,,of ,,bone4 ,illustration3 ,,fig4 #b4 ,structure of bone enlarged4 ,sidenote3 #e4 ,in what respect admirably fashioned8 ,its formation8 ,microscopic examination8 ,the inference8 ,line of beauty8 #e4 ,,the ,,structure ,,of ,,the ,,bones4--,if we examine one of the long bones1 which has been sawn through lengthwise1 we observe that it is admirably fashioned for affording lightness as well as strength 7,fig4 #a74 ,its exterior is hard and resisting1 but it is porous at the broad extremities1 while through the central portion there is a cavity or canal which contains an oily substance1 called marrow4 ,let us now take a thin section of bone1 and examine it under the microscope2 we discover that it is pierced by numerous fine tubes 7,fig4 #b71 about which layers of bone-substance are arranged4 ,accordingly1 though a bone be as hard as stone externally1 it is by no means as heavy as stone1 by reason of its light interior texture4 ,another element of power is found in the curved outline of the bones4 ,the curved line is said to be the line of beauty1 as it certainly is the line of strength1 and is uniformly employed in the bones whose position exposes them to accident4 #ah ,illustration3 ,,fig4 #c4--,,the ,,skeleton #ai ,sidenote3 #f4 ,number of bones8 ,skeleton8 ,the skull8 ,chest8 ,the trunk8 ,the trunk and skull1 how maintained8 ,what of the arms8 ,legs8 #f4 ,,the ,,skeleton4--,the number of bones in the human body exceeds two hundred4 ,when these are joined together in the proper places1 they form what is termed the ,skeleton 7,fig4 #c74 ,it embraces three important cavities4 ,the first1 surmounting the frame1 is a box of bone1 called the skull2 below this1 is a bony case1 or chest2 and lower down is a bony basin1 called the pelvis4 ,the two latter compose the trunk4 ,the trunk and skull are maintained in their proper relations by the spinal column4 ,branching from the trunk are two sets of limbs3 the arms1 which are attached to the chest by means of the collar-bone and shoulder-blade2 and the legs1 directly joined to the lower part of the trunk4 ,sidenote3 #g4 ,design of the cavities8 ,give the examples4 #g4 ,the cavities of which we have spoken1 are designed for the lodgment and protection of the more delicate and perishable parts of the system4 ,thus1 the skull1 together with the bones of the face1 shelters the brain and the organs of four senses--sight1 hearing1 smell1 and taste4 ,the chest contains the heart1 lungs1 and great blood-vessels1 while the lower part of the trunk sustains the liver1 stomach1 and other organs4 ,sidenote3 #h4 ,joint or articulation8 ,movable joints1 how compacted8 ,the ligaments of the movable joints8 ,what is a sprain8 ,consequence of a serious sprain8 #h4 ,,the ,,joints4--,the point of union of two or more bones forms a joint or articulation1 the connection being made in various ways according to the kind and amount of motion desired4 ,the movable joints are compacted together by certain strong fibrous bands1 called ligaments4 ,these ligaments are of a shining1 silvery whiteness1 and very unyielding2 so much so1 that when sudden violence is brought to bear in the vicinity of a joint1 the bone to which a ligament is attached may be broken1 while the ligament itself remains uninjured4 ,when this connecting material of the joints is strained or lacerated by an #bj accident1 a sprain is the consequence4 ,an injury of this sort may be1 and frequently is1 quite as serious as the breaking of a bone4 ,illustration3 ,,fig4 #d4--;,,cells ,,of ,,cartilage4 ,sidenote3 #i4 ,office of the ligament8 ,what must it have8 ,how accomplished8 ,describe it4 ,synovia8 #i4 ,the ligament1 then1 secures firmness to the joint2 it must also have flexibility and smoothness of motion4 ,this is accomplished by a beautiful mechanism the perfection of which is only feebly imitated by the most ingenious contrivance of man4 ,the ends of the bones are covered by a thin layer of cartilage1 which being smooth and elastic1 renders all the movements of the joint very easy4 ,in addition to this1 there is an arrangement introduced for lubricating the joint1 by means of a delicate sac containing fluid4 ,this fluid is constantly supplied in small quantities1 but only so fast as it is used up in exercise4 ,in appearance1 it is not unlike the white of an egg1 and hence its name synovia1 or egg-like4 ,sidenote3 #aj4 ,what do we observe as regards the composition of a joint8 ,the ligament and cartilage8 ,what varies8 ,example of the skull8 ,other examples8 ,the ball-and-socket joint8 #aj4 ,thus1 we observe1 that two very different substances enter into the composition of a joint4 ,the ligament1 very unyielding1 affords strength1 while the cartilage1 elastic and moist1 gives ease and smoothness of motion4 ,the amount of motion provided for varies greatly in different joints4 ,in some there is none at all1 as in the skull1 where one bone is dove-tailed into another by what are termed sutures4 ,others have a hinge-like motion1 such as those of the elbow1 wrist1 ankle1 and knee2 the most complete of these being the elbow-joint 7,fig4 #e74 ,belonging to another class1 the #ba ball-and-socket joint1 is that at the shoulder1 possessing a freedom of motion greater than any other in the body4 ,illustration3 ,,fig4 #e4--;,,elbow ,,joint4 ,a1 ,bone of the arm2 ,b1 ,c1 ,bones of the fore-arm4 ,sidenote3 #aa4 ,what is the spinal column8 ,what does it connect and form8 ,joints of the vertebr8 ,amount of motion8 ,result8 #aa4 ,,the ,,spinal ,,column4--,the spinal column is often spoken of as the back-bone1 as if it were a single bone1 while1 in reality1 it is composed of a chain of twenty-six small bones1 called vertebr4 ,the spinal column is a wonderful piece of mechanism4 ,it not only connects the important cavities of the body1 as has already been shown1 but1 also1 itself forms a canal1 which contains the spinal cord4 ,the joints of the vertebr are remarkable for the thick layers of cartilage which separate the adjacent surfaces of bone4 ,the amount of motion between any two of these bones is not great2 but these little movements1 taken together1 admit of very considerable flexibility1 in several directions1 without endangering the supporting power of the column4 #bb ,sidenote3 #ab4 ,elasticity of the frame8 ,protection of the brain from shocks8 ,tallness of persons8 ,effects of reclining8 ,illustration3 ,,fig4 #f--,,the ,,spinal ,,column4 #ab4 ,the abundant supply of intervertebral cartilage has another important use1 namely1 it adds greatly to the elasticity of the frame4 ,it is due1 in part1 to this elastic material1 and in part to the frequent curves of the spine1 that the brain and other delicate organs are protected from the shock of sudden falls or jars4 ,during the day1 the constant pressure upon these joints1 while the body is erect1 diminishes the thickness of the cartilages2 so that a person is not so tall in the evening as in the morning4 ,the effects of this compression pass away when the body reclines in a horizontal position4 ,sidenote3 #ac4 ,change in bone8 ,example--animal and madder4 ,rapidity of change in color8 ,waste and repair8 #ac4 ,,the ,,growth ,,of ,,bone4--,bone1 like all the other tissues of the body1 is constantly undergoing change1 old material being withdrawn1 and new particles taking their place4 ,this has been shown conclusively by experiments4 ,if an animal be fed with madder--a red coloring matter--for a day or two1 the bones soon become tinged2 then1 if the madder be discontinued for a few days1 the original color returns4 ,if1 however1 this material be alternately given and withheld1 at short intervals1 the bone will be marked by a succession of red and white rings4 ,in very young animals1 all the bones become colored in a single day2 in older ones1 a longer time is required4 ,the process of waste and repair1 therefore1 is constantly taking place in this hard substance1 and with astonishing rapidity4 #bc #ad4 ,,the ,,repair ,,of ,,bone4--,nature's provision for uniting broken bones is very complete4 ,at first1 blood is poured out around the ends of the bone1 as a result of the injury4 ,this is gradually absorbed1 and gives place to a watery fluid1 which1 thickening from day to day1 acquires1 at the end of two weeks1 the consistency of jelly4 ,this begins to harden1 by a deposit of new bone-substance1 until1 at the expiration of five or six weeks1 the broken bone may be said to be united4 ,it is1 however1 still fragile1 and must be used carefully a few weeks longer4 ,the process of hardening continues1 and months must pass before the union can be said to be complete4 ,,questions ,,for ,,topical ,,review4 ,,page #a4 ,what useful purposes do the bones serve8 #ae1 #af #b4 ,state what you can of the composition of the bones4 #af #c4 ,of the usefulness of lime in the bones4 #af #d4 ,of the usefulness of animal substance in the bones4 #af #e4 ,state what you can of the structure of the bones4 #ag #f4 ,of the strength belonging to the bones4 #ae1 #af1 #ag #g4 ,what is meant by the human skeleton8 #ai #h4 ,give a description of its construction4 #ai #i4 ,what is meant by a joint in the human frame8 #ai #aj4 ,state what you can of the movable joints4 #ai1 #bj #aa4 ,what office is performed by the ligaments of the joints8 #ai1 #bj #ab4 ,what by the cartilage at the joints8 #bj #ac4 ,what movable joints are there8 #bj1 #ba #ad4 ,describe the construction of the spinal column4 #ba #ae4 ,what properties and powers does the spinal column possess8 #ba1 #bb #af4 ,when is a person taller than at other times8 #bb #ag4 ,give the reason for this4 #bb #ah4 ,what can you state of the growth of bone8 #bb #ai4 ,describe the process by which a broken bone is repaired4 #bc 99 99 99 99 99 #bd ,illustration3 ,,fig4 #g4--,,the ,,muscles4 #be ,,chapter ,,ii4 ,,the ,,muscles4 ,the ,muscles--,flexion and ,extension--,the ,tendons--,contraction--,physical ,strength--,necessity for ,exercise--,its ,effects--,forms of ,exercise--,walking--,riding--,gymnastic s--,open-air ,exercise--,sleep--,recreation4 ,sidenote3 #a4 ,what are the muscles8 ,their number8 ,the design of most of them8 ,of a few8 #a4 ,,the ,,muscles4-- ,the great mass of the body external to the skeleton1 is composed of the flesh1 or ,muscles1 which largely determines its outline and weight4 ,the muscles are the organs of motion4 ,their number is about four hundred1 and to each of them is assigned a separate and distinct office4 ,they have all been studied1 one by one1 and a name given to each1 by the anatomist4 ,each is attached to bones which it is designed to move4 ,a few are circular in form1 and enclose cavities1 the size of which they diminish by contraction4 ,illustration3 ,,fig4 #h4--,,muscular ,,tissue4 a1 b1 ,striped muscular fibres3 c1 ,the same more highly magnified4 ,sidenote3 #b4 ,the structure of flesh8 ,its color1 etc48 ,the composition of the fibres8 ,how marked8 #b4 ,if we examine a piece of flesh1 we observe that it is soft1 and of a deep red color4 ,its structure appears to be composed of layers and bundles of small fibres4 ,let us further examine these fibres under the microscope4 ,we now discover that they are1 in turn1 made up of still finer fibres1 of fibrill3 these are seen in ,fig4 #h4 ,the fibres are beautifully #bf marked by parallel wavy lines1 about ten thousand to an inch1 which give the fibre its name of the striped muscular fibre4 ,all of the voluntary muscles present this appearance4 ,sidenote3 #c4 ,arrangement of the muscles8 ,their action8 ,flexion and extension8 ,action of the muscles when we stand erect8 #c4 ,,flexion ,,and ,,extension4--,the muscles are1 for the most part1 so arranged in pairs1 or corresponding sets1 that when motion is produced in one direction by one set1 there is1 opposite to it1 another muscle1 or group of muscles1 which brings the limb back to its place4 ,when they act alternately1 a to-and-fro movement results4 ,when a joint is bent1 the motion is called flexion2 and when it is made straight again1 it is called extension4 ,when both sets act equally1 and at the same moment1 no motion is produced1 but the body or limb is maintained in a fixed position3 this occurs when we stand erect4 ,the muscles which produce extension are more powerful than those opposite to them4 ,illustration3 ,,fig4 #i4--;,a1 ,biceps muscle of the arm3 ,b1 ,c1 ,its tendons4 ,sidenote3 #d4 ,kinds of muscles8 ,the voluntary8 ,involuntary8 ,the heart8 ,give the example4 ,the hand8 ,arm8 #d4 ,the muscles are also distinguished1 on the other hand1 as the voluntary and involuntary muscles1 according as they are1 or are not1 under the control of the will4 ,the heart is an example of the involuntary variety4 ,we cannot change its action in the least by an effort of the will4 ,when we sleep1 and the will ceases to act1 the heart continues to beat without cessation4 ,the voluntary muscles1 on the other hand1 are such as are used only when we wish or will to use them--as the muscles of the hand or arm 7,fig4 #i74 #bg ,sidenote3 #e4 ,what are the tendons or sinews8 ,their strength8 ,color8 ,location8 ,tendon of ,achilles8 ,the fable8 ,muscles of the leg8 #e4 ,,the ,,tendons4--,tendons1 or sinews1 are the extremities of muscles1 and are compactly fastened upon bone4 ,they are very strong1 and of a silvery whiteness4 ,they may be felt just beneath the skin1 in certain parts of the body1 when the muscles are being used1 as at the bend of the elbow or knee4 ,the largest tendon of the body is that which is inserted into the heel1 called the tendon of ,achilles1 after the hero of the ,grecian poet1 the fable relating that it was at this point that he received his death-wound1 no other part of his body being vulnerable4 ,the muscles which extend into the leg unite to form a single and very powerful tendon1 and enclose a small bone called the knee-pan1 which1 acting like a pulley1 greatly increases their power1 and at the same time protects the front of the knee-joint 7,fig4 #aj74 ,illustration3 ,,fig4 #aj4--,,view ,,of ,,knee-,,joint4 ,a1 ,thigh bone3 ,b1 ,knee-pan3 ,c1 ,d1 ,leg bones4 ,sidenote3 #f4 ,contraction of the muscles8 ,bending of the arm or finger8 ,other agencies8 ,automatic movements8 ,in cold-blooded animals8 #f4 ,,muscular ,,contraction4--,the muscles1 when acted upon by the appropriate stimulus1 contract1 or so change #bh their shape1 that their extremities are brought nearer together4 ,the bending of the arm1 or of a finger1 is effected in this manner1 by the will2 but the will is not the only means of producing this effect4 ,electricity1 a sharp blow over a muscle1 and other stimuli1 also cause it4 ,contraction does not always cease with life4 ,in man1 after death from cholera1 automatic movements of hands and feet have been observed1 lasting not less than an hour4 ,in certain cold-blooded animals1 as the turtle1 contraction has been known to take place for several days after the head has been cut off4 ,sidenote3 #g4 ,contractility8 ,give the illustration4 ,what was supposed8 ,what is the case8 #g4 ,the property which1 in muscle1 enables these movements to take place is called contractility4 ,if we grasp a muscle while in exercise 7for example1 the large muscle in the front of the arm71 we notice the alternate swelling and decrease of the muscle1 as we move the forearm to and fro4 ,it was at one time supposed that the muscle actually increased in volume during contraction4 ,this1 however1 is not the case2 for the muscle1 while gaining in thickness1 loses in length in the same proportion2 and thus1 the volume remains the same in action and at rest4 ,sidenote3 #h4 ,what further in relation to contraction8 ,weariness of a muscle8 ,beating of the heart8 ,standing and walking8 #h4 ,contraction is not the permanent1 or normal1 state of a muscle4 ,it cannot long remain contracted1 but after a shorter or longer time1 it wearies and is obliged to relax4 ,after a short rest1 it can then again contract4 ,it is for this reason that the heart can beat all through life1 night and day1 by having1 as we shall hereafter see1 a brief interval of rest between successive pulsations4 ,for the same reason1 it is more fatiguing to stand for any great length of time in one position1 than to be walking the same period4 ,sidenote3 #i4 ,muscular power of animals8 ,how tested8 ,man's power8 ,horse's8 ,the comparison8 #i4 ,,relative ,,strength ,,of ,,animals4--,the amount of muscular power which different animals can exert1 has #bi been tested by experiment4 ,by determining the number of pounds which an animal can drag upon a level surface1 and afterward comparing that with its own weight1 we can judge of its muscular force4 ,it is found that man is able to drag a little less than his own weight4 ,a draught-horse can exert a force equal to about two-thirds of his weight4 ,the horse1 therefore1 though vastly heavier than man1 is relatively not so powerful4 ,sidenote3 #aj4 ,power of insects8 ,beetles8 ,give the conclusion4 #aj4 ,insects are remarkable for their power of carrying objects larger and heavier than themselves4 ,many of them can drag ten1 and even twenty times their weight4 ,some of the beetles have been known to move bodies more than forty times their own weight4 ,so far1 therefore1 from it being a fact that animals have strength in proportion to their weight and bulk1 the reverse of that statement seems to be the law4 ,sidenote3 #aa4 ,difference in strength of individuals8 ,how caused8 #aa4 ,,physical ,,strength4--,the difference in strength1 as seen in different individuals1 is not due to any original difference in their muscles4 ,nature gives essentially the same kind and amount of muscles to each person1 and the power of one1 or the weakness of another1 arises1 in great part1 from the manner in which these organs are used or disused4 ,sidenote3 #ab4 ,complaint in relation to degeneracy8 ,how true8 ,how determined by armor8 ,the fair supposition8 #ab4 ,many authors complain of the physical degeneracy of men at the present day1 as compared with past generations4 ,there is room for doubt as to the correctness of this statement4 ,certain experiments have recently been made with the metallic armor worn seven hundred years ago1 by which it is found that any man1 of ordinary height and muscular development1 can carry the armor and wield the weapons of an age supposed to be greatly our superior in strength4 ,when we consider that in those days1 only very strong men could endure the hardships of soldier-life1 #cj it is fair to suppose that our age has not so greatly degenerated in respect to physical strength4 ,sidenote3 #ac ,action8 ,use of organs8 ,training of the mind8 ,the child's brain8 ,education of the body8 #ac4 ,,importance ,,of ,,exercise4--,action is the law of the living body4 ,every organ demands use to preserve it in full vigor1 and to obtain from it its best services4 ,the value of that training of the mind1 which we call education1 is everywhere recognized4 ,the child is early put to school1 and for many years continues to study1 in order that his brain1 which is the great centre of mental power1 may act healthfully and with force4 ,it is important that the body1 also1 should receive its education by exercise4 ,this is especially true of persons belonging to certain classes of society1 whose occupation confines them within doors1 and requires chiefly brain-work4 ,sidenote3 #ad ,work in the open air8 ,a perfect business8 ,the consequence of universal perfect business8 ,occupation of children8 #ad4 ,persons who are engaged in manual labor in the open air obtain all the exercise necessary for bodily health in their regular business3 their need is more likely to be a discipline or exercise of the mind4 ,a perfect business of life1 therefore1 would be one which would combine both physical and mental labor in their proper proportions4 ,if such a business were possible for all the human race1 life would thereby be vastly prolonged4 ,such is1 in fact1 to a large extent1 the occupation pertaining to one period of life--childhood4 ,a part of the time is spent by the child in improving his mind by study1 and another part of the time he has physical exercise in his games and sports4 ,sidenote3 #ae ,in what does exercise consist8 ,effects of it8 #ae4 ,,the ,,effects ,,of ,,exercise4--,exercise consists in a well-regulated use of the voluntary muscular system4 ,the effects1 however1 are not limited to the parts used4 ,other organs1 which are not under the control of the will1 are indirectly influenced by it4 ,for instance1 the heart beats more rapidly1 the skin acts more freely1 and #ca becomes hotter1 as well as the parts beneath it1 and the appetite and power of digestion are increased4 ,an increased exhalation from the lungs and skin purifies the current of the circulation1 and the body as a whole thrives under its influence4 ,sidenote3 #af4 ,general effect upon the muscles8 ,special effect8 ,effects of inaction8 ,of excessive exercise8 #af4 ,the immediate effect of exercise1 however1 is upon the muscles themselves2 for by use they become firm and large1 and increase in power4 ,if we examine a muscle thus improved by exercise1 we find that its fibres have become larger and more closely blended together1 that its color is of a darker red1 and that the supply of blood-vessels has increased4 ,without exercise the muscle appears thin1 flabby1 and pale4 ,on the other hand1 excessive exercise1 without sufficient relaxation1 produces in the muscle a condition not very different from that which follows disuse4 ,the muscle is worn out faster than nature builds it up1 and it becomes flabby1 pale1 and weak4 ,sidenote3 #ag4 ,of violent and spasmodic efforts8 ,strength1 how attained8 ,give the particulars4 #ag4 ,violent exercise is not beneficial2 and spasmodic efforts to increase the muscular strength are not calculated to secure such a result4 ,strength is the result of a gradual growth1 and is most surely acquired if the exercise be carried to a point short of fatigue1 and after an adequate interval of rest4 ,to gain the most beneficial results1 the exercise should be at regular hours1 and during a regular period4 ,the activity of the exercise1 and the time devoted to it must vary1 of course1 with the strength of the individual1 and should be carefully measured by it4 ,sidenote3 #ah4 ,what may walking be called8 ,what further is said of walking8 #ah4 ,,different ,,modes ,,of ,,exercise4--,there are very few who have not the power to walk4 ,there is required for it no expensive apparatus1 nor does it demand a period of preliminary training4 ,walking may be called the universal exercise4 ,with certain foreign nations1 the ,english #cb especially1 it is a very popular exercise1 and is practised habitually by almost every class of society2 by the wealthy as well as by those who have no carriages2 by women as well as by men4 ,sidenote3 #ai4 ,what is said of running1 and other like movements8 ,what1 as related to childhood8 ,what instances are alluded to8 ,example8 #ai4 ,running1 leaping1 and certain other more rapid and violent movements1 are the forms of exercise that are most enjoyed in childhood4 ,for the child1 they are not too severe1 but they may be so prolonged as to become injurious4 ,instances have been recorded where sudden death has resulted after violent playing1 from overtaxing the heart3 for example1 we have the case of a young girl who1 while skipping the rope1 and endeavoring to excel her playmates by jumping the greatest number of times1 fell dead from rupture of the heart4 ,sidenote3 #bj4 ,carriage-riding8 ,horseback-riding8 #bj4 ,carriage-riding1 as a means of passive exercise1 is particularly well suited to invalids1 and persons advanced in life4 ,horseback exercise brings into use a greater number of muscles than any other one exercise1 and with it there is an exhilaration of feeling which refreshes the mind at the same time4 ,it is one of the manliest of exercises1 but not less suitable for women than for men4 ,to be skilful in riding1 it is best to begin its practice in youth2 but there are very few kinds of exercise of which the same is not equally true4 ,sidenote3 #ba4 ,boating1 swimming1 and skating8 #ba4 ,for those who live near streams or bodies of water1 there are the delightful recreations of boating1 swimming1 and skating4 ,certain of these exercises have a practical importance aside from and above their use in increasing the physical vigor4 ,this is especially true of boating and swimming1 since they are often the means of saving life4 ,practice in these exercises also teaches self-reliance1 courage1 and presence of mind4 ,persons who have become proficient in these vigorous exercises are generally the ones1 #cc who1 in times of danger1 are the quickest to act and the most certain to do so with judgment4 ,sidenote3 #bb4 ,what kind of exercise yields the best results8 ,what advice is given8 #bb4 ,,physical ,,culture4--,that form of exercise which interests and excites the mind1 will yield the best results2 but to some persons no kind of exertion whatever is1 at first1 agreeable4 ,they should1 nevertheless1 make a trial of some exercise1 in the expectation that1 as they become proficient in it1 it will become more pleasant4 ,in exercise1 as many sets of muscles should be employed as possible1 open-air exercise being the best4 ,parlor gymnastics1 and the discipline of the gymnasium are desirable1 but they should not be the sole reliance for physical culture4 ,no in-door exercise1 however excellent in itself1 can fill the place of hearty and vigorous activity in the open air4 ,sidenote3 #bc4 ,physical culture among the ancients8 ,in ,greece8 ,in schools and colleges at the present time8 ,result to the body and mind8 #bc4 ,,gymnastic ,,exercises ,,for ,,schools ,,and ,,colleges4--,in the system of education among the ancients1 physical culture predominated4 ,in ancient ,greece1 physical exercises in schools were prescribed and regulated by law1 and hence these schools were called gymnasia4 ,at the present time1 on the contrary1 this culture is almost wholly unknown1 as a part of the course of education1 in our schools and colleges4 ,in a few of our institutions of learning1 however1 physical exercises have been introduced1 with manifest advantage to the students1 and they form a part of the regular curriculum of exercises1--as much so as the recitations in geography1 grammar1 or ,greek4 ,the good effect of the experiments1 as shown in improved scholarship as well as increased bodily vigor1 in the institutions where the plan has been tried1 will1 it is hoped1 lead to its universal adoption4 ,we should then hear less frequently of parents being obliged to withdraw their children from school1 because they become exhausted #cd or1 perchance1 have lost their health from intense and protracted mental application4 ,sidenote3 #bd4 ,the result of gymnastics in our colleges and other institutions of learning8 #bd4 ,were gymnastics more common in our educational institutions we should not so often witness the sad spectacle of young men and women leaving our colleges and seminaries1 with finished educations it may be1 but with constitutions so impaired1 that the life which should be devoted to the accomplishment of noble purposes must be spent in search of health4 ,spinal curvatures1 which1 according to the experience of physicians1 are now extremely frequent1 especially among ladies1 would give place to the steady gait and erect carriage which ,god designed his human creatures should maintain4 #be4 ,all the exercises necessary for the proper development of the body may be obtained from the use of a few simple contrivances that every one can have at home1 at little cost--less by far than is spent for useless toys4 ,many of these may be made available in the parlor or chamber1 though all exercises are far more useful in the open air4 ,a small portion of the day thus spent will afford agreeable recreation as well as useful exercise4 ,the ,indian club1 the wand1 the ring1 and the dumb-bells answer ordinary purposes very well4 ,illustrations are here introduced of a few simple contrivances that may be useful for general exercises1 and are specially suitable for persons with weak spines1 or with spines that are the subject of lateral curvature4 #bf4 ,one of the simplest appliances for strengthening the muscles of the spine1 designed chiefly to exercise the muscles on either side of the spine1 consists of two wooden handles attached to india-rubber cords1 one of which is attached to a hook made fast in the ceiling1 or in the top of the door-case2 and the other to another hook fastened in the wall1 door-post1 or window-casing1 about the height #ce of the shoulder4 ,when traction is made with the left hand1 it exercises the muscles on the left side of the spine1 while those on the opposite side are left almost at rest1 owing to the oblique direction given to the shoulders when the right hand grasps the horizontal cord4 7,this appliance will be understood by referring to ,fig4 #ac47 ,illustration3 ,,fig4 #aa4 ,illustration3 ,,fig4 #ab4 #cf #bg4 ,fig4 #aa shows an appliance consisting of two strong elastic cords1 with handles1 secured to a hook in the floor1 so arranged that the patient has to stoop forward to reach them4 ,on raising the body the spinal muscles are powerfully exercised4 ,fig4 #ab shows other modes of using the elastic cords for strengthening the spine and chest4 ,illustration3 ,,fig4 #ac4 #bh4 ,these various appliances have been combined so as to form a system of gymnastics suitable for parlor use2 other appliances have been added by which the muscles of #cg the legs may be called into action as well as those of the spine and upper part of the body 7,fig4 #ac74 ,combinations of cords suitable for particular cases may also be made1 and by using one or several cords on the same hook1 their power may be adapted to the strength of the most robust as well as to that of the invalid1 or of the most delicate child4 ,the entire apparatus is quite simple in its construction and inexpensive1 requiring but little space1 and at the same time affording a great variety of exercises4 ,,exercises ,,that ,,may ,,be ,,practised ,,on ,,this ,,apparatus4 ,,exercise ,i4 7,fig4 #ac74--,stand erect under the cords and place the heels together4 ,grasp the handles firmly1 keeping the knees and elbows stiff1 and pull downward and forward until the fingers nearly touch the toes4 ,return slowly to the erect position4 ,repeat4 ,,exercise ,,ii4 7,fig4 #ac74--,stand erect1 and having grasped the handles overhead firmly1 separate them and bring them down slowly until they touch the sides3 then return them slowly to the original position4 ,repeat4 ,,exercise ,,iii4 7,fig4 #ac74--,stand erect1 heels together1 grasp the handles overhead1 and charge forward with the right foot4 ,return to first position1 and then charge with the left4 ,repeat1 using the right and left foot alternately4 ,,exercise ,,iv4 7,fig4 #ac74--,stand erect1 heels together4 ,grasp the handle overhead1 and charge forward with the right foot1 knee bent4 ,remain in this position and bring the arms down to the sides so that the arm and fore-arm may form a right angle4 ,still holding the handles1 thrust forward1 first the right hand and then the left1 until the arm is straight4 ,repeat4 ,return to first position1 then charge forward with the left foot1 performing the same movements as before4 ,,exercise ,v4 7,fig4 #ac74--;,in this exercise we change to the pulleys leading from the side posts1 which can be used in several different ways4 #ast4 ,stand erect1 heels together1 facing one of the posts1 grasp the handle with the right hand1 the arm being extended1 then flex the fore-arm on the arm4 ,repeat4 ,perform the same movements with the left hand4 #b;d4 ,stand with back to the post2 grasp the pulley behind with the right hand1 then gradually bring the hand forward until it is extended in a straight line in front4 ,repeat4 ,perform the same exercise with the left hand4 #ch ,,exercise ,,vi4 7,fig4 #ac74--,this exercise is especially adapted to the legs4 ,stirrups are so arranged that they can be attached to the pulleys overhead1 and can hang down to within three or four feet of the floor4 ,place the foot in the stirrup1 and then press down until it touches the floor4 ,repeat4 ,exercise the left foot in the same way4 ,,exercise ,,vii4 7,fig4 #ac47--,this exercise requires a little attention in the adjustment of the apparatus4 ,under the pulleys in the floor are passed ropes which can be attached to the snap-hooks that hold the handles overhead4 ,stoop forward with the knees stiff1 and take hold of the handles1 and then raise the body to the erect position4 ,repeat4 ,,exercise ,,viii4 7,fig4 #ac74--,sit on the floor or on a seat three or four inches high2 bend forward1 take hold of the handles1 and perform the same movements that you would in rowing a boat4 ,,exercise ,,ix4 7,fig4 #ac74--,the trapeze can now be let down2 take hold of it with both hands1 sustaining the weight of the body with the arms1 then rotate the body first from right to left1 then from left to right alternately4 ,this exercise is especially suitable for females4 ,,exercise ,x4 7,fig4 #ac74--;,grasp the trapeze as before1 bearing all the weight with the arms3 then draw the body up slowly until you can place the chin over the bars4 ,this requires strength of muscle1 and might strain if done too violently2 if slowly performed there is no danger4 ,these are but a few of the exercises that can be practised with this apparatus4 ,as these become familiar they can easily be modified1 and new ones can be arranged to meet the requirements of particular cases4 ,most of the exercises described can be practised with one hand so as to strengthen the muscles on one side4 ,sidenote3 #bi4 ,need of repose8 ,how do we obtain rest8 ,alfred the ,great8 ,the eight-hour division of time8 #bi4 ,,rest4--,we cannot always be active3 repose must succeed labor4 ,we obtain this rest partly by suspending all exertion1 as in sleep1 and partly by a change of employment4 ,it is said that ,alfred the ,great recommended that each day should be divided in the following manner3 ,eight hours for work1 eight hours for recreation1 and eight hours for sleep4 ,this division of time is as good as any that could now be made1 if it be borne in mind that1 when the work is physical1 the time of recreation should #ci be devoted to the improvement of the mind2 and when mental1 we should then recreate by means of physical exercise4 ,sidenote3 #cj4 ,cessation of voluntary activity8 ,temperature of the body8 ,consequence8 ,body and mind during sleep8 ,nutrition8 ,describe it4 ,consequences of insufficient sleep8 #cj4 ,during sleep1 all voluntary activity ceases1 the rapidity of the circulation and breathing diminishes1 and the temperature of the body falls one or two degrees4 ,in consequence1 the body needs warmer coverings than during the hours of wakefulness4 ,during sleep1 the body seems wholly at rest1 and the mind is also inactive1 if we except those involuntary mental wanderings which we call dreams4 ,nevertheless a very active and important physical process is going on4 ,nutrition1 or the nourishing of the tissues1 now takes place4 ,while the body is in action1 the process of pulling down predominates1 but in sleep1 that of building up takes place more actively4 ,in this way we are refreshed each night1 and prepared for the work and pleasures of another day4 ,if sleep is insufficient1 the effects are seen in the lassitude and weakness which follow4 ,wakefulness is very frequently the forerunner of insanity1 especially among those who perform excessive mental labor4 ,sidenote3 #ca4 ,amount of sleep in different persons8 ,cases8 ,frederick the ,great8 ,bonaparte8 ,instances of long deprivation of sleep8 #ca4 ,all persons do not require the same amount of sleep1 but the average of men need from seven to nine hours4 ,there are well-authenticated cases where individuals have remained without sleep for many days without apparent injury4 ,frederick the ,great required only five hours of sleep daily4 ,bonaparte could pass days with only a few hours of rest4 ,but this long continued absence of sleep is attended with danger4 ,after loss of sleep for a long period1 in some instances1 stupor has come on so profoundly1 that there has been no awaking4 ,sidenote3 #cb4 ,instances of sailors8 ,french soldiers8 ,during torture8 #cb4 ,there are instances related of sailors falling asleep #dj on the gun-decks of their ships while in action4 ,on the retreat from ,moscow1 the ,french soldiers would fall asleep on the march1 and could only be aroused by the cry1 ,the ,cossacks are coming6 ,tortured persons are said to have slept upon the rack in the intervals of their torture4 ,in early life1 while engaged in a laborious country practice1 the writer not unfrequently slept soundly on horseback4 ,these instances1 and others1 show the imperative demand which nature makes for rest in sleep4 ,,questions ,,for ,,topical ,,review4 ,,page #a4 ,what can you state of the number and division of the muscles8 #be1 #bf #b4 ,describe the structure of the muscles4 #be1 #bf #c4 ,their arrangement in pairs and consequent action4 #bf #d4 ,what is the difference between the motion called flexion and that called extension8 #bf #e4 ,describe their action1 and state which are the more powerful4 #bf #f4 ,what is the difference between voluntary and involuntary muscles8 #bf #g4 ,illustrate the difference between the two4 #bf #h4 ,state all you can of the tendons or sinews4 #bg #i4 ,what is meant by contraction of the muscles8 #bg1 #bh #aj4 ,in how many and what ways may contraction be effected8 #bh #aa4 ,what is stated of after-death contraction8 #bh #ab4 ,why cannot a muscle in life continue contracted a long time8 #bh #ac4 ,how then can the constant beating of the heart be explained8 #bh #ad4 ,how does the strength of a man compare with that of a horse8 #bi #ae4 ,what can you state in relation to the relative strength of animals8 #bh1 #bi #af4 ,what1 in relation to physical strength8 #bi #ag4 ,what1 in relation to physical degeneracy8 #bi1 #cj #ah4 ,what1 in relation to the importance of exercise8 #cj #ai4 ,what is the effect of exercise upon the heart1 skin1 and appetite8 #cj1 #ca #bj4 ,how does exercise affect the current of the body's circulation8 #ca #ba4 ,how does judicious exercise affect the muscles8 #ca #bb4 ,what is stated of violent and spasmodic exercise8 #ca #bc4 ,of the exercise of walking8 #ca1 #cb1 #cc #bd4 ,of running1 leaping1 and other modes of exercise8 #cb #be4 ,of physical culture1 in connection with out-door exercises8 #cc #bf4 ,of the importance of gymnastics in our schools and colleges8 #cc1 #cd #bg4 ,of the importance of rest from labor or exercise8 #ch1 #ci #bh4 ,what processes take place during sleep8 #ci #bi4 ,what effects follow insufficient sleep8 #ci 99 99 99 99 99 #da ,,chapter ,,iii4 ,,the ,,integument1 ,,or ,,skin4 ,the ,integument--,its ,structure--,the ,nails and ,hair--,the ,complexion--,the ,sebaceous ,glands--,the ,perspiratory ,glands--,perspiration and its ,uses--,importance of ,bathing--,different kinds of ,baths--,manner of ,bathing--,the ,benefits of the ,sun--,importance of ,warm ,clothing--,poisonous ,cosmetics4 ,sidenote3 #a4 ,what is the skin8 ,parts directly beneath8 ,what is shown8 #a4 ,,the ,,integument4--,the skin is the outer covering of the body4 ,the parts directly beneath it are very sensitive1 and require protection4 ,this is shown whenever by accident the skin is broken1 pierced1 or torn off1 the bared surface being very tender1 and painful to the touch4 ,nature has provided the body with a garment that is soft1 pliable1 close-fitting1 and very thin1 and yet sufficiently strong to enable us to come in contact with the objects that surround us1 without inconvenience or suffering4 ,sidenote3 #b4 ,microscopic examination8 ,what is the cutis8 ,the cuticle8 ,their union8 ,how separated8 ,what further is said of the cuticle8 #b4 ,,the ,,structure ,,of ,,the ,,skin4--,when examined with the aid of the microscope1 the skin is found to be made up of two layers--the outer and the inner4 ,the inner one is called the cutis1 or true skin2 the outer one is the epidermis1 or scarf-skin4 ,the latter is also known as the cuticle4 ,these two layers are closely united1 but they may be separated from each other4 ,this separation takes place whenever1 from a burn1 or other cause1 a blister is formed2 a watery fluid is poured out between the two layers1 and lifts the epidermis from the true skin4 ,of the two layers1 the cuticle is the thinner in most parts of the body1 and has the appearance of a whitish membrane4 ,it is tough and elastic1 is without feeling1 and does #db not bleed1 when cut4 ,examine it more closely1 and we observe that it is composed of minute flat cells1 closely compacted1 and arranged layer upon layer4 ,sidenote3 #c4 ,wearing out of the cuticle8 ,what then8 ,variety in thickness of cuticle8 ,how accounted for8 #c4 ,the outer layer is constantly being worn out1 and falls from the body in the form of very fine scales4 ,it is1 also1 continually forming anew on the surface of the inner layer4 ,its thickness varies in different parts of the body4 ,where exposed to use1 it is thick1 hard1 and horn-like1 as may be seen on the soles of the feet1 or on the palms of the hands1 especially of those who are accustomed to perform much manual labor4 ,this is an admirable provision for the increased protection of the sensitive parts below the skin against all extraordinary exposure4 ,even the liabilities of these parts to injury1 are thus kindly provided for by the ,hand that made us4 ,sidenote3 #d4 ,location and office of the cutis8 ,what further is said of it8 ,papill8 ,touch8 #d4 ,the cutis1 or true skin1 lies beneath the epidermis1 and is its origin and support4 ,it is firm1 dense1 elastic1 very sensitive1 and is freely supplied with blood-vessels4 ,it is closely connected with the tissues below it1 but may be separated by means of a sharp instrument4 ,the surface of the cutis is not smooth1 but is covered here and there with minute elevations1 called papill4 ,these are arranged in rows1 along fine lines1 or ridges1 such as those which mark the palm and fingers2 their number is about #hj to the square line 7a line being one-twelfth of an inch74 ,these papill contain the blood-vessels which carry the supply of blood needed by the ever-wasting skin4 ,they contain nerves also1 and are largely concerned in the sense of touch2 hence they are particularly abundant where the touch is most delicate1 as at the ends of the fingers4 ,sidenote3 #e4 ,what are the nails and hair8 ,the growth of the nail8 ,the rapidity of its growth8 ,accident to the nail8 #dc ,illustration3 ,fig4 #ad4 a1 b4 ,,the ,,root ,,of ,a ,,hair4 #a1 #b1 #c4 ,the skin forming the hair sac4 #d4 ,sebaceous glands4 #e4 ,the hair sac4 c4 ,,transverse ,,section ,,of ,a ,,hair4 #e4 ,,the ,,nails ,,and ,,hair4--,these are appendages of the skin1 and although very unlike the cuticle as it appears on the surface of the body1 they are1 in reality1 modified forms of that layer of the skin4 ,the nail grows from a fold of the cuticle at the root1 and from the under surface4 ,as fast as it is formed1 it is constantly being pushed outward4 ,the rapidity of its growth can be ascertained by filing a slight groove on its surface1 and noticing how the space between it and the root of the nail increases1 in the course of a few weeks4 ,when the nail is removed by any accident1 it will be replaced by a new one1 if the root be not injured4 ,sidenote3 #f4 ,how are the hairs produced8 ,difference in their length8 #f4 ,the hairs are produced in a similar manner2 the skin forming depressions1 or hair sacs1 from the bottom of which they grow and are nourished 7,fig4 #ad74 ,they are found1 of greater or less length1 on almost all parts of the surface1 except the palms of the hands and soles of the feet4 ,on certain parts of the body1 they grow to great length2 on other parts they are so short1 that they do not rise beyond the hair sac in which they originate4 ,sidenote3 #g4 ,root of the hair8 ,shaft8 ,firmness and softness of the hair8 #g4 ,the bulb1 or root1 from which the hair arises1 is lodged in a small pouch1 or depression in the skin4 ,the shaft is the part which grows out beyond the level of the skin4 ,its growth is altogether in one direction1 in length alone4 ,the outer part of the hair is quite firm1 while its #dd interior is softer1 and probably conveys the fluids by which it is nourished4 ,the hair is more glossy in health than at other times4 ,sidenote3 #h4 ,office of the nail8 ,of the hair8 ,give the illustrations4 #h4 ,the nail serves as a protection to the end of the finger1 and also enables us to grasp more firmly1 and to pick up small objects4 ,the hair1 too1 is a protection to the parts it covers4 ,on the head1 it shields the brain from extremes of heat and cold1 and moderates the force of blows upon the scalp4 ,on the body1 it is useful in affording a more extensive surface for carrying off the perspiration4 ,sidenote3 #i4 ,on what does the complexion depend8 ,light and dark races8 ,freckles8 #i4 ,,complexion4--,in the deeper cells of the cuticle lies a pigment1 or coloring matter1 consisting of minute colored grains4 ,on this pigment complexion depends2 and1 according as it is present in less or greater amount1 occasions the difference of hue1 that exists between the light and dark races of men1 and between the blonde and brunette of the white races4 ,freckles are due to an irregular increase of coloring matter4 ,sidenote3 #aj4 ,influence of the sun8 ,how illustrated8 ,jews8 #aj4 ,the sun has a powerful influence over the development of this pigment1 as is shown by the swarthy hue of those of the white race who have colonized in tropical climates4 ,it is also well illustrated by the fact1 that among the ,jews who have settled in northern ,europe1 there are many who are fair complexioned1 while those residing in ,india1 are as dark as the ,hindoos around them4 ,sidenote3 #aa4 ,what is an ,albino8 ,where are ,albinos found8 #aa4 ,an ,albino is a person who may be said to have no complexion2 that is1 there is an entire absence of coloring matter from the skin1 hair1 and iris of the eye4 ,this condition more frequently occurs among the dark races1 and in hot climates1 although it has been observed in almost every race and clime4 ,sidenote3 #ab4 ,what are sebaceous glands8 ,how do they act8 ,sebaceous glands of the face8 ,how do they act8 #ab4 ,,sebaceous ,,glands4--,there are in the skin certain #de small glands1 which produce an oily substance1 called sebaceous matter4 ,these glands are little rounded sacs1 usually connected with the hair-bulbs2 and upon these bulbs1 they empty their product of oil1 which acts as a natural and adequate dressing for the hair 7#d1 ,fig4 #ad74 ,a portion of the sebaceous matter passes out upon the surface1 and prevents the cuticle from becoming dry and hard4 ,the glands situated upon the face and forehead1 open directly upon the skin4 ,in these1 the sebaceous matter is liable to collect1 and become too hard to flow off naturally4 ,sidenote3 #ac4 ,black points1 called worms8 ,animalcules8 ,service performed by sebaceous matter8 #ac4 ,these glands on the face and forehead frequently appear1 on the faces of the young1 as small black points1 which are incorrectly called worms4 ,it is true1 that occasionally living animalcules are found in this thickened sebaceous matter1 but they can only be detected by the aid of the microscope4 ,this sebaceous matter acts not only to keep the skin flexible1 and furnish for the hair an oily dressing1 but it especially serves to protect the skin and hair1 from the acridity arising from the perspiration4 ,sidenote3 #ad4 ,perspiration8 ,sweat glands8 ,of what do they consist8 ,dimension of the tubes8 #ad4 ,,the ,,perspiratory ,,glands4--,the chief product of the skin's action is the perspiration4 ,for the formation of this1 there are furnished countless numbers of little sweat-glands in the true skin4 ,they consist of fine tubes1 with globe-like coils at their deeper extremity4 ,their mouths or openings may be seen with an ordinary magnifying glass1 upon the fine ridges which mark the fingers4 ,these tubes1 if uncoiled1 measure about one-tenth of an inch in length4 ,in diameter1 they are about one three-hundredth of an inch1 and upon certain parts of the body there are not far from three thousand of these glands to the square inch4 ,their whole number in the body is1 therefore1 very great2 and1 in fact1 it is computed if they were all united1 end to end1 their combined measurement would exceed three miles4 #df ,sidenote3 #ae4 ,what is sensible perspiration8 ,insensible perspiration8 #ae4 ,,the ,,sensible ,,and ,,insensible ,,perspiration4--,the pores of the skin are constantly exhaling a watery fluid2 but1 under ordinary circumstances1 there is no moisture apparent upon the surface1 for it evaporates as rapidly as it is formed4 ,this is called insensible perspiration4 ,under the influence of heat or exercise1 however1 this fluid is excreted more abundantly1 and appears on the surface in the form of minute1 colorless drops4 ,it is then termed sensible perspiration4 ,sidenote3 #af4 ,components of perspiration8 ,upon what does perspiration depend8 ,amount of perspiration daily8 #af4 ,water is the chief component of this fluid1 there being about ninety-eight parts of water to two parts of solid matter4 ,the quantity escaping from the body varies greatly1 according to the temperature of the air1 the occupation of the individual1 and other circumstances4 ,the average daily amount of this excretion1 in the adult1 is not far from thirty ounces1 nearly two pints1 or more than nine grains each minute4 ,sidenote3 #ag4 ,what does perspiration set free from the blood8 ,what other service does perspiration perform8 ,explain the process4 #ag4 ,,the ,,uses ,,of ,,the ,,perspiration4--,besides liberating from the blood this large amount of water1 with the effete matter it contains1 the perspiration serves to regulate the temperature of the body4 ,that is to say1 as evaporation always diminishes temperature1 so the perspiration1 as it passes off in the form of fine vapor1 cools the surface4 ,accordingly1 in hot weather this function is much more active1 and the cooling influence increases in proportion4 ,when the air is already charged with moisture1 and does not readily receive this vapor of the body1 the heat of the atmosphere apparently increases1 and the discomfort therefrom is relatively greater4 ,sidenote3 #ah4 ,effect of interruption of excretion8 ,what experiments are mentioned8 #ah4 ,the importance of this excretion is shown by the effects that often follow its temporary interruption1 namely1 headache1 fever1 and the other symptoms that accompany #dg taking cold4 ,when the perspiration is completely checked1 the consequences are very serious4 ,experiments have been performed upon certain smaller animals1 as rabbits1 to ascertain the results of closing the perspiratory tubes4 ,when they are covered by a coating of varnish impervious to water and gases1 death ensues in from six to twelve hours2 the attendant symptoms resembling those of suffocation4 ,sidenote3 #ai4 ,give the story in relation to the boy covered with gold foil4 #ai4 ,it is related that1 at the coronation of one of the ,popes about three hundred years ago1 a little boy was chosen to act the part of an angel2 and in order that his appearance might be as gorgeous as possible1 he was covered from head to foot with a coating of gold foil4 ,he was soon taken sick1 and although every known means were employed for his recovery1 except the removal of his fatal golden covering1 he died in a few hours4 ,sidenote3 #bj4 ,give the quotation4 ,perspiration8 #bj4 ,,the ,,importance ,,of ,,bathing4--,from these considerations1 it is evident that health must greatly depend upon the free action of the skin4 ,he who keeps the skin ruddy and soft1 shuts many gates against disease4 ,when the watery portion of the perspiration evaporates1 the solid matter is left behind on the surface4 ,there1 also1 remain the scales of the worn-out cuticle1 and the excess of sebaceous matter4 ,in order to secure the natural action of the skin1 these impurities require to be removed by the frequent application of water4 ,sidenote3 #ba4 ,ablution in warm climates8 ,what advice is given8 #ba4 ,in warm climates1 and during hot weather1 ablution should be more frequently practised4 ,for a person in good health1 a daily cold bath is advisable4 ,to this should be added occasionally a tepid bath1 with soap1 water alone not being sufficient to remove impurities of a greasy nature4 ,soap facilitates this1 by forming with such substances a chemical mixture1 which is readily soluble in water1 and is by it removed from the body4 #dh ,sidenote3 #bb4 ,liebig's maxim8 ,what further is added8 #bb4 ,there is a maxim by the chemist ,liebig1 to the effect1 that the civilization of a nation is high1 in proportion to the amount of soap that it consumes2 and that it is low1 in proportion to its use of perfumes4 ,in some degree1 we may apply the same test to the refinement of an individual4 ,the soap removes impurity2 the perfume covers1 while retaining it4 ,sidenote3 #bc4 ,what is said about cold bathing8 #bc4 ,,the ,,different ,,kinds ,,of ,,baths4--,all persons are not alike able to use the cold bath4 ,when the health is vigorous1 and the system does not feel a shock after such a bath1 a prompt reaction and glow upon the surface will show that it is beneficial4 ,where this pleasurable feeling is not experienced1 but rather a chill and sense of depression ensues1 we are warned that the system will not1 with impunity1 endure cold bathing4 ,sidenote3 #bd4 ,what is said about warm bathing8 #bd4 ,it should also be borne in mind1 that the warm or hot bath cannot be continued so long1 or repeated so frequently as the cold1 on account of the enervating effect of unusual heat so applied to the body4 ,for persons who are not in robust health1 one warm bath each week is sufficient2 this class should be careful to avoid every extreme in reference to bathing1 clothing1 and whatever greatly affects the action of the skin4 ,sidenote3 #be4 ,what is said about sea-bathing8 #be4 ,sea-bathing is even more invigorating than fresh-water bathing4 ,those who cannot endure the fresh water1 are often benefited by the salt-water baths4 ,this may be accounted for1 in part1 by the stimulant action upon the surface1 of the saline particles of the sea-water2 but the exciting scenes and circumstances of sea-bathing also exert an important influence4 ,the open-air exercise1 the rolling surf1 the genial weather1 and usually the cheerful company1 add to its intrinsic benefits4 #di ,sidenote3 #bf4 ,what is said as to the time and manner of bathing8 #bf4 ,,time ,,and ,,manner ,,of ,,bathing4--,a person in sound health may take a bath at almost any time1 except directly after a full meal4 ,the most appropriate time is about three hours after a meal1 the noon-hour being probably the best4 ,for the cold bath1 taken rapidly1 no time is better than immediately after rising4 ,those beginning the use of cold baths should first try them at #gj ,fahr41 and gradually use those of a lower temperature4 ,from five to twenty minutes may be considered the proper limit of time to remain in a bath2 but a sensation of chilliness is a signal to withdraw instantly1 whether at home1 or at the sea-side4 ,two sea-baths may be taken daily2 one of any other kind is sufficient4 ,sidenote3 #bg4 ,condition of the body when bathing8 ,direction1 after bathing8 #bg4 ,the body should be warm1 rather than cold1 when stepping into the bath2 and after it1 the skin should be thoroughly dried with a coarse towel4 ,it is best to continue friction until there is a sensation of warmth or glow throughout the entire surface4 ,this reaction is the test of the good effects of the bath4 ,if reaction is still incomplete1 a short walk may be taken1 especially in the sunshine4 ,it is very congenial1 however1 both to health and comfort1 to rest for a short time directly after bathing1 or to take some light refreshment4 ,this is better than severe exercise or a full meal4 ,sidenote3 #bh4 ,bathing among the ancients8 ,baths of ,rome8 #bh4 ,,bathing ,,among ,,the ,,ancients4--,the ,romans and other nations of antiquity made great use of the vapor-bath as a means of preserving the health1 but more particularly as a luxury4 ,their method was not unlike that employed in northern ,europe at the present day4 ,the public baths of ,rome and other cities are among the grandest and most interesting monuments of ancient luxury and splendor2 and from their ruins have been recovered some of the most beautiful works of art4 #ej ,sidenote3 #bi4 ,after the bath8 ,swimming among the ancients8 #bi4 ,the ,therm1 as the baths of ,rome were called1 were of great extent1 built very substantially1 and ornamented at vast expense4 ,they were practically free to all1 the cost of a bath having been less than a cent4 ,it is related that some persons bathed seven times a day4 ,after the bath their bodies were anointed with perfumed oil4 ,if the weather was fine1 they passed directly from the ,therm into the gymnasium1 and engaged in some gentle exercise previous to taking the midday meal4 ,between two and three in the afternoon was the favorite hour for this ancient luxury4 ,swimming was a favorite exercise1 and a knowledge of it was regarded as necessary to every educated man4 ,their common expression1 when speaking of an ignorant person1 was1 ,he can neither read nor swim4 ,sidenote3 #cj4 ,the ,sun-bath8 ,the story of ,pliny8 #cj4 ,,the ,,sun-,,bath4--,some also were accustomed daily to anoint themselves1 and lie or walk in apartments arranged for the purpose1 with naked bodies exposed to the direct rays of the sun4 ,there is an interesting allusion to this practice1 in a letter of the younger ,pliny to the historian ,tacitus1 describing the destruction of ,pompeii by an eruption of ,vesuvius4 ,my uncle1 7,pliny the elder17 was at that time in command of the fleet at ,misenum4 ,on the #bdth of ,august1 about one in the afternoon1 my mother desired him to notice a cloud which seemed of unusual shape and dimensions4 ,he had just returned from taking the benefit of the sun1 and after a cold bath1 and a slight repast1 had retired to his study4 ,then follows a description of the destruction of ,pompeii1 and the death of the elder ,pliny4 ,sidenote3 #ca4 ,benefit of the sun8 ,effect upon plants8 ,skin8 #ca4 ,we may judge somewhat of the benefits of the sun1 by observing the unnatural and undeveloped condition of plants and animals which are deprived of light4 ,plants become blanched and tender2 the fish of #ea subterranean lakes1 where no light enters1 are undersized1 and have no eyes2 tadpoles kept in the dark do not develop into frogs2 men growing up in mines are sallow1 pale1 and deformed4 ,besides the well-known effect of solar light in tanning the skin1 it also makes it thicker and better able to resist exposure2 though the complexion may be thereby injured1 the health gains more than compensate for the loss of beauty4 ,to make good the loss of the lily1 where the sun has cast his ray1 he seldom fails to plant the rose4 ,sidenote3 #cb4 ,direction about clothing8 ,exposing limbs of children8 ,clothing1 night and day8 #cb4 ,,clothing4--,in reference to clothing1 we are far more apt1 in our changeful climate1 to use too little than too much4 ,an aphorism of ,boerhaave1 worth remembering1 if not of adopting1 is1 ,we should put off our winter clothing on midsummer's day1 and put it on again the day after4 ,he also says1 ,only fools and beggars suffer from the cold2 the latter not being able to get sufficient clothes1 the others not having the sense to wear them4 ,the practice of exposing the limbs and necks of young children1 for the alleged purpose of hardening them1 is quite hazardous4 ,it is not to be denied that some seem to be made tough by the process2 but it is so only with the rugged children1 the delicate ones will invariably suffer under this fanciful treatment4 ,as has been stated before1 the skin is constantly acting1 by night as well as by day4 ,it is therefore conducive both to cleanliness and comfort to change entirely the clothing on retiring for the night4 ,the day-clothing should be aired during the night1 and the bedding should be aired in the morning1 for the same reason4 ,sidenote3 #cc4 ,cosmetics8 ,painters' colic8 #cc4 ,,poisonous ,,cosmetics4--,the extensive use of cosmetics for the complexion is a fertile source of disease4 ,the majority of these preparations contain certain poisonous mineral substances1 chiefly lead4 ,now1 the skin rapidly absorbs the fine particles of lead1 and the system #eb experiences the same evil effects that are observed among the operatives in lead works and painters1 namely1 painters' colic1 and paralysis of the hands1 called wrist-drop4 #cd4 ,certain hair-dyes also contain lead1 together with other noxious and filthy ingredients4 ,these do not work as great harm as the cosmetics1 since they are purposely kept away from the skin1 but they rob the hair of its vitality4 ,eye-washes1 too1 are made from solutions of lead1 and many an eye has been ruined by their use4 ,they deposit a white metallic scale on the surface of the eye1 which becomes a permanent obstruction to the vision4 ,,questions ,,for ,,topical ,,review4 ,,page #a4 ,what are the characteristics of the skin1 and what office does it perform8 #da #b4 ,what can you state of the structure of the skin8 #da #c4 ,describe the cuticle and tell its use4 #da1 #db #d4 ,describe the cutis or true skin and tell its use4 #db #e4 ,what can you state of the nature and growth of the nail8 #db1 #dc #f4 ,of the nature and growth of the hair8 #db1 #dc1 #dd #g4 ,of the offices performed by the nails and hair8 #dd #h4 ,how is the difference in complexion in different persons accounted for8 #dd #i4 ,how is the presence of freckles accounted for8 #dd #aj4 ,how does ,nature provide a dressing for the hair8 #dd1 #de #aa4 ,what other service do the sebaceous glands perform8 #de #ab4 ,state what you can of the perspiratory glands4 #de #ac4 ,what is the difference between sensible and insensible perspiration8 #df #ad4 ,state the uses and importance of perspiration4 #df1 #dg #ae4 ,what impurities gather naturally on the skin8 #dg #af4 ,repeat what is said of the importance of bathing4 #dg1 #dh #ag4 ,when should we indulge in cold1 warm1 and sea bathing8 #dh1 #di #ah4 ,what is the effect in each case8 #dh #ai4 ,what directions are given as to the time and manner for bathing8 #di #bj4 ,what is related of bathing among the ancients8 #di1 #ej #ba4 ,what is related to show the antiquity of sun-bathing8 #ej #bb4 ,what are the effects of sun-bathing8 #ej1 #ea #bc4 ,what directions are given in relation to clothing the body8 #ea #bd4 ,what can you state of poisonous cosmetics8 #ea1 #eb #be4 ,of hair-dyes and eye-washes8 #eb 99 99 99 99 99 #ec ,,chapter ,,iv4 ,,the ,,chemistry ,,of ,,food4 ,the ,source of ,food--,inorganic ,substances--,water--,salt--,lime--,iron --,organic ,substances--,albumen1 ,fibrin1 and ,casein--,the ,fats or ,oils--,the ,sugars1 ,starch1 and ,gum--,stimulating ,substances--,necessity of a ,regulated ,diet4 ,sidenote3 #a4 ,the term food8 ,source of food8 ,need of preparing food8 #a4 ,,the ,,source ,,of ,,food4--,the term food includes all those substances1 whether liquid or solid1 which are necessary for the nourishment of the body4 ,the original source of all food is the earth1 which the poet has fitly styled the ,mother of all living4 ,in her bosom1 and in the atmosphere about her1 are contained all the elements on which life depends4 ,but man is unable to obtain nourishment directly from such crude chemical forms as he finds in the inorganic world4 ,they must1 with a few exceptions1 be prepared for his use1 by being transformed into new and higher combinations1 more closely resembling the tissues of his own body4 ,sidenote3 #b4 ,usefulness and hurtfulness of plants8 ,what then must man do8 ,parts of the same plant or tree8 #b4 ,this transformation is effected1 first1 by the vegetable world4 ,but all plants are not alike useful to man2 while some are absolutely hurtful4 ,accordingly1 he must learn to discriminate between that which is poisonous and that which is life-supporting4 ,again1 all parts of the same plant or tree are not alike beneficial3 in some1 the fruit1 in others1 the leaves1 and in others1 the seeds only are sufficiently refined for his use4 ,these he must learn to select2 he must also learn the proper modes of preparing each kind for his table1 whether by cooking or other processes4 #ed ,sidenote3 #c4 ,certain forms of vegetable creation8 ,example of the bee8 ,cattle8 ,the inference8 #c4 ,again1 certain forms of the vegetable creation which are unfit1 in their crude state1 for man's food1 and which he rejects1 are chosen as food by some of the lower animals1 and are1 by them1 made ready for his use4 ,thus the bee takes the clover1 that man cannot eat1 and from it collects honey4 ,the cattle eat the husks of corn and the dried grass1 that are by far too coarse for man1 and in their own flesh convert them into tissues closely resembling his muscular tissue4 ,in this way1 by the aid of the transforming processes of the vegetable and animal creations1 the simple chemical elements of the mineral kingdom are elaborated into our choice articles of food4 ,sidenote3 #d4 ,what classification8 ,define organic substances4 ,inorganic4 ,organic1 how spoken of8 ,the inorganic8 ,water and salt8 #d4 ,,inorganic ,,substances4--,the substances we use as food are classified as organic and inorganic4 ,by organic substances are meant those derived from living forms1 such as vegetables and animals4 ,inorganic substances are those simpler inanimate forms which belong to the mineral kingdom4 ,the former alone are commonly spoken of as food1 but the latter enter very largely into the constitution of the body1 and must therefore be present in our food4 ,with the exception of two articles1 water and common salt1 these substances only enter the system when blended with organic substances4 ,sidenote3 #e4 ,water in physiology8 ,where found8 ,computation8 ,water in the teeth8 ,muscle1 tendons1 and ligaments8 ,how ascertained8 ,water in the fluids of the body8 ,what is the advantage8 #e4 ,,water4--,water1 from a physiological point of view1 is the most important of all the articles of food4 ,it is everywhere found in the body1 even in the bones and the teeth4 ,it has been computed that as large a proportion as two-thirds of the body is water4 ,the teeth1 the densest of the solids in the human system1 contain ten per cent4 of water4 ,the muscles1 tendons1 and ligaments are more than half water2 for it is found that they lose more than half their #ee weight when dried with moderate heat4 ,but it is in the fluids of the body that water is found most abundantly4 ,it gives to them the power of holding a great variety of substances in solution1 and is the great highway by which new supplies are conveyed to the point where they are required1 and by which old particles of matter1 that have served their uses1 are brought to the outlets of the body to be thus removed from the system4 ,sidenote3 #f4 ,length of time man can do without food or water8 ,give the comparison8 ,bulk of drinks8 ,constituent of meats1 etc48 ,fruits8 #f4 ,man can remain a longer time without solid food than without water4 ,he may be deprived of the former for ten to twelve hours without great suffering1 but deprivation of water for the same length of time will produce both severe pain and great weakness4 ,the food should contain not less than two parts of water to one of solid nutriment4 ,water constitutes the great bulk of all our drinks1 and is also a large constituent of the meats1 vegetables1 and fruits which come upon the table4 ,fruits1 especially1 contain it in great abundance1 and1 in their proper season1 furnish most agreeable and refreshing supplies of the needed fluid4 ,sidenote3 #g4 ,salt1 how obtained8 ,where found8 ,in the human body8 ,importance of salt8 ,what else can you state of the value of salt8 #g4 ,,common ,,salt4--,salt1 or sodium chloride1 as an article of food1 is obtained chiefly from the mineral kingdom2 although plants contain it in small quantities1 and it is also found in the tissues of nearly all animals used as food4 ,in the human body1 it is an ingredient of all the solids and fluids4 ,the importance of salt to animal life in general1 is shown by the great appetite for it manifested by domestic animals1 and also by the habitual resort of herds of wild beasts to the salt-licks or springs4 ,in those parts of the world where salt is obtained with difficulty1 man places a very high price upon it4 ,sidenote3 #h4 ,experiments upon animals8 #h4 ,experiments upon domestic animals show that the withdrawal of salt from their food1 not only makes their #ef hides rough and causes the hair to fall out1 but also interferes with the proper digestion of food4 ,if it be withheld persistently1 they become entirely unable to appropriate nourishment1 and die of starvation4 ,sidenote3 #i4 ,salt1 how taken into the system8 ,its use in cooking8 ,consumption8 #i4 ,salt is usually taken into the system in sufficient quantities in our food4 ,even the water we drink often has traces of it4 ,the habitual use of much salt in cooking1 or as a seasoning at the table1 is not wise2 and while it may not lead to consumption1 as some writers declare1 it is a bad habit in itself1 and leads to the desire for other and more injurious condiments4 ,sidenote3 #aj4 ,lime in the bones8 ,what does it impart8 ,chief ingredient of the bones and teeth8 ,where else found8 #aj4 ,,lime4--,this is the mineral substance which we have spoken of before as entering very largely into the composition of the bones4 ,it is the important element which gives solidity and permanence to the framework upon which the body is built4 ,calcium tri-phosphate1 or bone-earth1 is the chief ingredient of the bones and teeth1 but is found in the cartilages and other parts of the body in smaller quantities4 ,sidenote3 #aa4 ,how does lime find its way into the body8 ,early life8 ,effect of its derivation8 #aa4 ,how does this substance find its way into the body8 ,meat1 milk1 and other articles obtained from the animal kingdom contain it1 and it is abundantly stored away also in the grains from which our bread is made1 in wheat1 rye1 and ,indian corn4 ,in early life1 while the body is growing1 the supplies of this substance should be carefully provided4 ,the evil effects of the deprivation of it are too often and painfully evident in the softening of the bones1 and in the predisposition to curvature of the spine--deformities which are most deplorable and which continue through life4 ,sidenote3 #ab4 ,iron1 its abundance and diffusion8 ,where found8 ,what part of the blood is it8 ,how supplied to the system8 ,in case of loss of blood or wasting disease8 #ab4 ,,iron4--,this substance is probably the most abundant and widely diffused of the metals4 ,it is found in #eg most of the vegetables1 and is a very important component of animal tissues4 ,it enters into the composition of human blood in about one part per thousand4 ,ordinarily1 the food conveys to the system enough iron for its use1 but it must sometimes be introduced separately as a remedy1 especially after great loss of blood1 or after some wasting disease4 ,under its influence the blood seems to be rapidly restored1 and a natural color of the lips and skin replaces the pallor caused by disease4 ,sidenote3 #ac4 ,soda1 potash1 and magnesia8 ,how do they occur8 #ac4 ,,other ,,inorganic ,,substances4--,in addition to the substances mentioned1 the mineral kingdom supplies compounds of soda1 potash1 and magnesia1 which are essential for the use of the body4 ,they occur in small quantities in the body1 and enter it in combination with the various articles of diet4 ,sidenote3 #ad4 ,organic substances1 whence derived8 ,what do they comprise8 ,groups8 #ad4 ,,organic ,,substances4--,these substances are derived from the vegetable and animal creations4 ,they comprise all those articles which are commonly spoken of as food1 and which are essential to sustain the body in life and strength4 ,they are divided into three groups1 namely3 the ,albuminoid substances1 the ,fats1 and ,sugars4 ,sidenote3 #ae4 ,the ,albuminoid class1 includes what8 ,these compounds constitute what8 ,the food8 ,their importance8 ,their properties8 #ae4 ,,the ,,albuminoids4--,this class includes three important nutritive substances--7#a7 ,albumen1 which gives it its name2 7#b7 ,fibrin1 including gluten2 and 7#c7 ,casein4 ,these compounds constitute a large part of the human body1 and the food contains them in proportionally large quantities4 ,their importance is so great1 and the system so promptly suffers from their absence1 that they have been styled the nutritious substances4 ,the properties which they hold in common are1 that they do not crystallize1 and have a jelly-like form1 except when heat is applied to them1 when they harden1 or coagulate4 #eh ,sidenote3 #af4 ,decomposition8 ,effect of cold8 ,illustrations8 ,elephants8 #af4 ,they likewise decompose1 or putrefy1 under the influence of warmth and moisture4 ,hence the decay of all dead animal tissues4 ,cold arrests this process4 ,it is well known that milk1 eggs1 and the like1 keep much longer in winter than at other seasons4 ,the bodies of elephants1 caught in the ice many hundred years ago1 are occasionally borne by the icebergs to the coast of ,siberia1 completely frozen1 but preserved almost perfectly in form and limb4 ,sidenote3 #ag4 ,in what substances does albumen exist8 ,what further is said of the egg8 #ag4 ,,albumen exists in milk1 meat1 the grains1 and the juices of many plants2 but the purest form is obtained from the white of egg4 ,when we consider that an egg is composed chiefly of albumen and water--namely1 six parts in seven2 and when we also consider the numerous1 diverse1 and complex tissues--the muscles1 bones1 internal organs1 bill1 claws1 and feathers--with which the chick is equipped on leaving his shell1 we are impressed with the importance of these apparently simple constituents of the food and body4 ,sidenote3 #ah4 ,fibrin1 gluten1 clotting of the blood8 #ah4 ,,fibrin is derived from meats1 and exists in the blood both of man and the lower animals4 ,gluten1 or vegetable fibrin1 resembles closely true fibrin1 and is abundantly furnished in wheat and other grains from which flour is commonly made4 ,animal fibrin coagulates spontaneously when it is removed from the body1 and thus causes the clotting of the blood4 ,sidenote3 #ai4 ,casein8 ,its coagulation8 ,effect of rennet8 ,making of cheese8 #ai4 ,,casein is the curdy ingredient of milk1 and a highly important food-substance4 ,its coagulation in milk takes place not from heat1 but by the addition of an acid1 and also when milk becomes sour from exposure to the air4 ,it is commonly effected1 however1 by introducing a piece of rennet1 a preparation made from a calf's stomach4 ,the curds1 or casein1 may then be separated from the whey1 #ei and made into cheese1 by pressing it sufficiently to drive off the water4 ,sidenote3 #bj4 ,what are the fats8 ,the oils8 ,how supplied8 ,how alike8 ,emulsifying8 ,example8 ,how do we know it8 #bj4 ,,the ,,fats ,,or ,,oils4--,this is the second group of organic foods4 ,those which are more solid are called fats3 the more fluid ones are the oils4 ,oleaginous substances are supplied in both animal and vegetable food2 but1 from whatever source derived1 they are chemically much alike4 ,they are insoluble in water1 and yet they unite readily with the watery fluids of the body1 and are by them conveyed to its various parts for their nourishment4 ,this is due to their property of emulsifying2 that is1 they are held in suspension1 in a finely divided state1 in water4 ,ordinary milk is an example of an emulsion4 ,we know that it contains fat2 for butter is obtained from it1 and1 under the microscope1 the minute oil-globules may be distinctly seen4 ,sidenote3 #ba4 ,whence are fatty articles of food derived8 #ba4 ,in our country and climate1 and also in colder climates1 fatty articles of food are principally derived from the animal creation1 such as meat or flesh1 milk and butter4 ,but most of the bread-stuffs contain more or less fat or oil2 ,indian meal as much as nine parts in a hundred4 ,sidenote3 #bb4 ,appetite of persons in cold climates8 ,what do they require8 ,upon what must they rely8 ,why8 ,the ,esquimaux8 ,laplander8 ,olive and palm8 #bb4 ,among persons living in cold climates1 the appetite for oleaginous food is especially eager2 and they require large quantities of it to enable them to resist the depressing influences of cold4 ,since vegetation is scanty and innutritious1 and the waters of the frozen regions abound in animal life1 they must rely wholly upon a diet derived from the latter source4 ,the ,esquimaux consumes daily from ten to fifteen pounds of meat or blubber1 a large proportion of which is fat4 ,the ,laplander will drink train-oil1 and regards tallow-candles as a great delicacy4 ,in hot climates1 on the contrary1 where flourish the olive #fj and the palm1 this kind of food may be obtained from vegetable sources in abundant quantities4 ,sidenote3 #bc4 ,which are the third of the organic groups8 ,what do they embrace8 ,points of resemblance8 #bc4 ,,the ,,sugars1 ,,or ,,the ,,saccharine ,,substances4--,these constitute the third1 and last1 group of the organic substances1 which are employed as food4 ,this group embraces1 in addition to the different kinds of ,sugar1 the varieties of starch and gum1 from whatever source derived4 ,the two substances last named do not1 at first sight1 present many points of similarity to sugar2 but they closely resemble it in respect to their ultimate chemical composition1 being made up of the same elements1 in nearly the same proportions4 ,and their office in the system is the same1 since they are all changed into sugar by the processes of digestion4 ,sidenote3 #bd4 ,origin of the sugars8 ,ordinary sugar8 ,beetroot8 ,maple-sugar8 ,grape-sugar8 ,cane-sugar8 #bd4 ,,sugar is chiefly of vegetable origin2 the animal varieties being obtained from honey and milk4 ,the most noticeable characteristic of this substance is its agreeable1 sweet taste1 which makes it everywhere a favorite article of food4 ,but this quality of sweetness is not possessed by all the varieties of sugar in the same degree2 that obtained from milk1 for instance1 has a comparatively feeble taste1 but rather imparts a gritty feeling to the tongue4 ,the other important properties of sugar are1 its power to crystallize when evaporated from watery solutions1 such as the juices of many plants2 a tendency to ferment1 by which process alcohol is produced2 and a ready solubility in water4 ,this latter quality renders it very easy of digestion1 and more so than any other of the saccharine group4 ,it is computed that the annual production of sugar1 in all parts of the world1 is more than one million of tons4 ,the kind of sugar that is in ordinary use1 in this country1 is prepared from the juice of the sugar-cane1 which contains eighteen per cent4 of sugar4 ,in ,france it is manufactured from the #fa beet root1 which holds about nine per cent42 the maple-tree of our climate yields a similar sugar4 ,the sweet taste of fruits is due to the presence of grape-sugar3 the white grains seen on raisins belong to this variety4 ,cane-sugar is more soluble than the latter1 and has twice the sweetening power4 ,illustration3 ,,fig4 #ae4--;,,granules ,,of ,,potato ,,starch4 ,sidenote3 #be4 ,starch1 how widely distributed8 ,its qualities8 ,its constituents8 ,its solubility8 #be4 ,,starch4--,this is the most widely distributed of the vegetable principles4 ,it is tasteless1 inodorous1 and does not crystallize4 ,it consists of minute rounded granules1 which1 under the microscope1 reveal a somewhat uniform structure 7,fig4 #ae74 ,starch will not dissolve in cold water1 but in boiling water the small grains burst open1 and may then be dissolved and digested4 ,sidenote3 #bf4 ,how much starch in bread-stuffs8 ,in rice8 ,unripe fruits8 ,ripe fruits8 #bf4 ,the bread stuffs1 wheat1 corn1 and rye flours1 are more than one-half starch4 ,rice1 which is the staff of life to one-third of the human family1 contains eighty per cent4 ,unripe fruits have much starch in them1 which renders them indigestible when eaten uncooked2 for the grains of raw starch are but slightly acted upon within the body4 ,but1 under the potent chemistry of the sun's ray1 this crude material is converted into sugar4 ,thus are the fruits prepared by the careful hand of ,nature1 so that when ripe they may be freely used without further preparation4 ,sidenote3 #bg4 ,gum1 where found8 ,its composition8 ,gum ,arabic8 #bg4 ,,gum is commonly found in those articles which #fb also contain starch2 and has the same chemical composition as the latter1 but is much less nutritious4 ,in the ,east1 gum-arabic and similar substances are largely employed as food4 ,persons who travel by caravan across vast1 sandy deserts1 find such substances well adapted to their wants1 since they are not perishable1 and are easily packed and carried4 ,sidenote3 #bh4 ,the three classes of food principles8 ,what besides8 ,what is said of them8 ,name the articles not nutritious4 #bh4 ,,stimulating ,,substances4--,the three classes of food-principles already considered--the ,albuminoids1 the ,fats1 and the ,sugars--comprise all the more important organic ingredients of our food4 ,there are1 besides1 a great variety of coloring and flavoring matters that stimulate or increase the appetite for food by appealing to the eye and taste2 but they are not nutritious1 and are quickly separated from the truly useful substances1 and do not long remain in the body4 ,among these may be classed spices1 flavors of fruits1 tea1 coffee1 and vegetable acids4 ,sidenote3 #bi4 ,what is said of experiments that have been tried8 #bi4 ,,necessity ,,of ,a ,,regulated ,,diet4--,a great variety of experiments have been tried in order to test the relative value of the different nutritive principles4 ,they have been practised to some extent upon man1 but chiefly upon those inferior animals which require a similar diet to man4 ,sidenote3 #cj4 ,what has been demonstrated in the first place8 ,example8 ,second demonstration8 ,example8 ,give the illustration in relation to convertibility4 #cj4 ,by this means it has been demonstrated that--first1 when any one of these substances is eaten exclusively1 the body is imperfectly nourished1 and life is shortened4 ,dogs fed exclusively upon either albumen1 fat1 or sugar1 soon die of starvation4 ,second1 a diet long deprived of either of these principles1 is a fertile cause of disease2 for example1 on ship-board1 where fresh vegetables are not dealt out for a long period1 scurvy becomes prevalent among the sailors4 ,they are1 however1 to a certain extent mutually convertible1 and thus the missing article is indirectly supplied4 ,for #fc instance1 sugar changes to fat in the body2 and hence1 as is well known1 the hands on a sugar plantation grow fat during the sugar season1 by partaking freely of the ripened juices of the cane4 #ca4 ,that is the best diet therefore which contains some of each of these principles1 in due proportion2 and that is the worst which excludes the most of them4 ,the cravings and experience of man had unerringly guided him to a correct regulation of his diet1 long before the chemistry of food was understood2 so that his ordinary meals long ago combined these various principles1 the necessity and value of which are now explained4 ,,questions ,,for ,,topical ,,review4 ,,page #a4 ,what is understood by the term food8 #ec #b4 ,what can you state in relation to the source of food8 #ec #c4 ,what discriminations and selections are necessary8 #ec1 #ed #d4 ,how can you tell the organic from the inorganic substances8 #ed #e4 ,what relative position does water hold as an article of food8 #ed #f4 ,in what parts of the body is water found8 #ed1 #ee #g4 ,in what articles that we eat is it found8 #ee #h4 ,if you were required to go without water or solid food for a number of days1 which would you prefer to have1 and why8 #ee #i4 ,what can you state of the importance of salt as an article of food8 #ee1 #ef #aj4 ,how abundant is salt1 and how does it find its way into the human system8 #ee1 #ef #aa4 ,what can you state of the importance of lime in the body8 #ef #ab4 ,what1 of the importance of iron8 #ef1 #eg #ac4 ,what further is stated of other inorganic substances8 #eg #ad4 ,what in relation to organic substances8 #eg #ae4 ,what can you state in relation to the albuminoids8 #eg1 #eh #af4 ,what1 in relation to albumen8 #eh #ag4 ,what1 in relation to casein8 #eh1 #ei #ah4 ,in relation to the fats or oils1 and how generally consumed8 #ei1 #fj #ai4 ,what do we understand by the sugars or saccharine substances8 #fj #bj4 ,state what you can of sugar--its origin and various qualities4 #fj1 #fa #ba4 ,of starch--its varieties and qualities4 #fa #bb4 ,of the abundance of starch1 and its importance as a food principle4 #fa #bc4 ,what is stated in relation to stimulating substances8 #fb #bd4 ,of the necessity for regulation in diet8 #fb1 #fc 99 99 99 99 99 #fd ,,chapter ,v4 ,,food ,,and ,,drink4 ,necessity for ,food--,waste and ,repair--,hunger and ,thirst--,amount of ,food--,renovation of the ,body--,mixed ,diet--,milk--,eggs--,meat--,cooking--,v egetable ,food--,bread--,the ,potato--,fruits--,purity of ,water--,action of ,water upon ,lead--,coffee1 ,tea1 and ,chocolate--,effects of ,alcohol4 ,sidenote3 #a4 ,what follow activity8 ,examples8 ,necessity for food8 #a4 ,,necessity ,,for ,,food4--,activity is everywhere followed by waste4 ,the engine uses up coal and water to produce motion1 the stream wears away its bank1 the growing corn-blade draws tribute from the soil4 ,when the human body acts1 and it is always in action during life1 some of its particles are worn out and thrown off4 ,this waste must constantly be repaired1 or the body suffers4 ,in this fact is seen the necessity for food4 ,the particles1 thus worn out1 being henceforth useless1 are removed from the body4 ,our food and drink are rapidly transformed into a new supply of living1 useful material1 to be in turn used up and replaced by a fresher supply4 ,sidenote3 #b4 ,give the theory in relation to waste and repair4 #b4 ,,waste ,,and ,,repair4--,in this way the healthful body1 though always wasting1 is always building up1 and does not greatly change in size1 form1 or weight4 ,at two periods of life the processes of waste and repair are not exactly balanced4 ,in early life the process of building up is more active1 and in consequence the form is plump1 and the stature increases4 ,repair now exceeds waste4 ,on the other hand1 when old age comes on1 the wasting process is more active1 the flesh and weight diminish1 the skin falls in wrinkles1 and the senses become dull4 ,only during the prime of life--from about twenty to sixty years of age--is the balance exact between loss and gain4 #fe ,sidenote3 #c4 ,system deprived of food8 ,warning8 ,what is the pain8 ,how proved8 #c4 ,,hunger ,,and ,,thirst4--,when the system is deprived of its supply of solid food during a longer time than usual1 nature gives warning by the sensation of hunger1 to repair the losses that have taken place4 ,this sensation or pain appears to be located in the stomach1 but it is really a distress of the system at large4 ,let a sufficient quantity of nourishment be introduced into the system in any other way than by the mouth1 and it will appease hunger just as certainly as when taken in the usual manner4 ,sidenote3 #d4 ,feeling of thirst8 ,seat of the pain8 ,how proved8 ,time a person can exist without food8 #d4 ,the feeling of thirst1 in like manner1 is evidence that the system is suffering from the want of water4 ,the apparent seat of the distress of thirst is in the throat2 but the injection of water into the blood-vessels is found to quench thirst1 and by the immersion of the body in water1 the skin will absorb sufficient to satisfy the demands of the system4 ,the length of time that man can exist without food or drink is estimated to be about seven days4 ,if water alone be supplied1 life will last much longer2 there being cases recorded where men have lived twenty days and over1 without taking any solid food4 ,sidenote3 #e4 ,amount of food required8 ,the young and others8 ,those living in hot and cold climates8 ,habits8 #e4 ,,quantity ,,of ,,food4--,the quantity of food required varies greatly1 according to the individual and his mode of life4 ,the young1 and others who lead active lives1 or who live in the open air1 require more food than the old1 the inactive1 or the sedentary4 ,those who live in cold regions require more than the inhabitants of hot climates4 ,habit1 also1 has much to do with the quantity of food required4 ,some habitually eat and drink more than they actually need1 while a few eat less than they should4 ,sidenote3 #f4 ,quantity of food daily8 ,how divided8 ,compare with the weight of the body8 #f4 ,the average daily quantity of food and drink for a healthy man of active habits is estimated at six pounds4 ,this amount may be divided in about the following #ff proportions3 the mineral kingdom furnishes three and one-half pounds1 including water and salt2 the vegetable kingdom1 one and one-half pounds1 including bread1 vegetables1 and fruits2 the animal kingdom1 one pound1 comprising meat1 eggs1 butter1 and the like4 ,this quantity is about one twenty-fourth the weight of the body1 as it is generally computed2 the average weight of an adult man being placed at #adj pounds4 ,a man1 therefore1 consumes an amount of solid and liquid nutriment every twenty-four days equal in weight to that of his body1 a corresponding amount being excreted1 or removed from the system in the same time4 ,sidenote3 #g4 ,how often then might the body be renewed8 ,why is it not8 ,opinion8 ,how correct8 ,what further is stated8 #g4 ,,renovation ,,of ,,the ,,body4--,by this process1 so far as weight is concerned1 the body might be renewed every twenty-four days2 but these pounds of food are not all real nutriment4 ,a considerable portion of that which we eat is innutritious1 and though useful in various ways1 is not destined to repair the losses of the system4 ,an opinion has prevailed that the body is renewed throughout once in seven years2 how correct this may be it is not easy to decide1 but probably the renovation of the body takes place in a much shorter period4 ,some parts are very frequently renewed1 the nutritive fluids changing more or less completely1 several times during the day4 ,the muscles1 and other parts in frequent exercise1 change often during a year2 the bones not so often1 and the enamel of the teeth probably never changes after being once fully formed4 ,sidenote3 #h4 ,habits of nations8 ,give the different cases4 #h4 ,,mixed ,,diet4--,the habits of different nations in respect to diet exhibit the widest and strangest diversity4 ,the civilized1 cook their food1 while savages often eat it in a raw state4 ,some prefer it when fresh1 others allow it to remain until it has become tainted with decay4 ,those dwelling in the far north subsist almost wholly on #fg animal food1 while those living in hot climates have bountiful supplies of delicious fruits with which to satisfy all their bodily wants4 ,one race subsists upon the banana1 another upon the blubber of seals4 ,in temperate climates1 a diet composed partly of vegetable and partly of animal food is preferred4 ,sidenote3 #i4 ,the point to consider8 ,vegetable diet8 ,louis ,cornaro8 ,john the ,baptist8 #i4 ,the important point to consider is1 however1 not one of origin1 but whether the chemical principles 7mentioned in the last chapter7 enter into the composition of the diet4 ,a purely vegetable diet may be selected which would contain all the principles necessary to sustain life4 ,it is recorded of ,louis ,cornaro1 a ,venetian noble1 that he supported himself comfortably for fifty-eight years on a daily allowance of twelve ounces of vegetable food1 and about a pint of light wine4 ,on the other hand1 the food of ,john the ,baptist1 consisting of locusts and wild honey1 is an example of the sustaining power of a diet chiefly animal in its origin4 ,sidenote3 #aj4 ,what has been found in our climate8 ,exclusive vegetable diet8 #aj4 ,in our climate1 those who lead active lives crave an allowance of animal food2 and it has been found by experience that with it they can accomplish more work and are less subject to fatigue1 than without it4 ,among nations where an exclusively vegetable diet is employed1 indigestion is a disorder especially prevalent4 ,sidenote3 #aa4 ,necessity for change in diet8 ,continuous use of the same diet8 ,exception8 ,why8 ,too rich diet8 ,horses8 #aa4 ,the necessity for occasionally changing or varying the diet1 is seen in the fact that no single article comprises all the necessary principles of food1 and that the continuous use of any one diet1 whether salt or fresh1 is followed by defective nutrition and disease4 ,there is one exception to this rule3 in infancy1 milk alone is best calculated to support life2 for then the digestive powers are incompletely developed1 and the food must be presented in the simplest form possible4 ,it should also be remembered #fh that too rich diet is injurious1 just as truly as one that is inadequate4 ,when the food of horses is too nutritious1 instinct leads them to gnaw the wood-work of their mangers4 ,sidenote3 #ab4 ,milk as a model food8 ,cow's milk8 ,the constituents when separated8 #ab4 ,,different ,,articles ,,of ,,diet--,,milk4--,milk is the earliest nutriment of the human race1 and in the selection and arrangement of its constituents1 may be regarded as a model food1 no other single article being capable of sustaining life so long4 ,cow's milk holds casein1 one of the albuminoids1 about five parts in one hundred2 a fatty principle1 when separated1 known as butter1 about four parts2 sugar of milk four parts2 water and salts eighty-seven parts4 ,the casein and fatty substance are far more digestible in milk1 than after they have been separated from it in the form of cheese and butter4 ,sidenote3 #ac4 ,milk as a beverage8 ,milk sold in cities8 ,how to detect the cheat8 #ac4 ,since milk1 in itself1 is so rich an article of food1 the use of it as a beverage is unwise1 unless the quantity of the other articles consumed be reduced at the same time4 ,the milk sold in cities is apt to be diluted with water4 ,the way to detect the cheat is by testing the specific gravity of the article4 ,good milk is about #ajcj2 skimmed milk #ajce2 but milk diluted one-fifth is #ajbd4 ,an instrument called the lactometer is also used1 by which the amount of cream present is ascertained4 ,sidenote3 #ad4 ,composition of eggs8 ,yolk8 ,how should eggs be eaten8 ,why8 ,how boiled8 ,why8 #ad4 ,,eggs4--,the egg is about two-thirds water1 the balance is pure albumen and fat in nearly equal proportions4 ,the fat is in the yolk1 and gives it its yellow color4 ,eggs contain none of the sugar-principles1 and should be eaten with bread or vegetables that contain them4 ,soft-boiled eggs are more wholesome than those which are hard-boiled or fried1 as the latter require longer time to digest4 ,sidenote3 #ae4 ,meats1 whence derived8 ,why important8 ,flesh of young animals8 #ae4 ,,meats4--,the meats1 so called1 are derived from the muscular parts of various animals4 ,they are most #fi important articles of food for adults1 inasmuch as they are richly stored with albuminoid substances1 and contain more or less fat4 ,such food is very nourishing and easily digested if eaten when fresh1--veal and pork being exceptions4 ,the flesh of young animals is more tender and1 in general1 more digestible than that of older ones4 ,all meat is more tough immediately after the killing of the animal1 but improves by being kept a certain length of time4 ,sidenote3 #af4 ,preference of persons8 ,venison8 ,mutton8 ,cheese8 ,uncooked flesh8 #af4 ,some persons prefer flesh that has begun to show signs of decomposition1 or is unmistakably putrid4 ,by some1 venison is not considered to have its proper flavor until it is tainted4 ,in ,england1 people prefer mutton that is in a similar condition1 just as on the continent of ,europe many delight in cheese that is in a state of decomposition4 ,in certain less civilized countries flesh is not only eaten uncooked1 but in a mouldy1 rotten condition4 ,the use of such food is not always immediately injurious1 but it predisposes to certain diseases1 as indigestion and fevers4 ,sidenote3 #ag4 ,cold as a preserver8 ,meat in ,russia8 ,beef and pork1 how preserved8 ,salted meat as food8 ,scurvy8 #ag4 ,cold is one means of preserving meat from decay4 ,in the markets of northern ,russia1 the frozen carcases of animals stand exposed for sale in the winter air for a considerable time1 and are sawn in pieces1 like sticks of wood1 as the purchases are made2 such meat1 when thawed1 being entirely fit for food4 ,beef and pork are preserved by salting down in brine1 and in this condition may be carried on long voyages or kept for future use4 ,salted meat is not as nutritious as fresh1 since the brine absorbs its rich juices and hardens its fibres4 ,long continued use of salt meats1 without fresh vegetables1 gives rise to the disease called scurvy1 formerly very prevalent on shipboard and in prisons2 but now scarcely known4 ,sidenote3 #ah4 ,the antiquity of the custom of cooking food8 ,object of cooking8 ,the oyster8 ,raw meat as an occasional food8 #ah4 ,,cooking4--,the preparation of food by the agency #gj of fire is of almost universal practice1 even among the rudest nations4 ,the object of cooking is to render food more easy of digestion by softening it1 to develop its flavor1 and to raise its temperature more nearly to that of the body4 ,a few articles of flesh-food are eaten uncooked in civilized lands1 the oyster being an instance4 ,raw meat is occasionally eaten by invalids with weak digestive powers1 and by men training for athletic contests4 ,sidenote3 #ai4 ,effect of boiling meat8 ,how may the cooking be done8 ,the proper method8 ,effect8 ,making of soup8 #ai4 ,in boiling meat1 the water in which it is placed tends to dissolve its nutrient juices4 ,in fact1 the cooking may be so conducted as to rob the meat of its nourishment1 its tenderness1 and even of its flavor4 ,the proper method1 in order to preserve or promote these qualities1 is to place the meat in boiling water1 which1 after a few minutes1 should be reduced in temperature4 ,in this way the intense heat1 at first1 coagulates the exterior layers of albumen1 and imprisons the delicate juices2 after that1 moderate heat best softens it throughout4 ,when soup is to be made1 an opposite course should be pursued2 for then the object is to extract the juices and reject the fibre4 ,meat1 for such purpose1 should be cut in small pieces and put into cold water1 which should then be gradually raised to boiling heat4 ,sidenote3 #bj4 ,roasting8 ,how should it be done8 ,give the philosophy of the process4 ,frying8 #bj4 ,roasting is probably the best method of cooking meat1 especially joints or large pieces1 as by this process the meat is cooked in its own juices4 ,roasting should begin with intense heat1 and be continued at a moderate temperature1 in order to prevent the drying out of the nutritious juices1 as by this process an outer coating or crust of coagulated albumen is formed4 ,during this process the meat loses one-fourth of its weight1 but the loss is almost wholly water1 evaporated by the heat4 ,too #ga intense or prolonged heat will dry the meat1 or burn it4 ,frying is the worst possible method1 as the heated fat1 by penetrating the meat1 or other article placed in it1 dries and hardens it1 and thus renders it indigestible4 ,sidenote3 #ba4 ,what is ,trichina8 ,how guarded against8 #ba4 ,,trichina4--,it should be remembered that ham1 sausages1 and other forms of pork1 should never be eaten in a raw or imperfectly cooked condition4 ,the muscle of the pig is often infested by a minute animal parasite1 or worm1 called trichina spiralis4 ,this worm may be introduced alive into the human body in pork food1 where it multiplies with great rapidity1 and gives rise to a painful and serious disease4 ,this disease has been prevalent in ,germany1 and cases of it occur from time to time in this country4 ,sidenote3 #bb4 ,what part of fish is eaten8 ,what does it resemble8 ,fish as food for digestion8 ,fish as a diet8 #bb4 ,,fish4--,the part of fish that is eaten is the muscle1 just as in the case of the meats and poultry4 ,it closely resembles flesh in its composition1 but is more watery4 ,some varieties are very easy of digestion1 such as salmon1 trout1 and cod2 others are quite indigestible1 especially lobsters1 clams1 and shell-fish generally4 ,a diet in which fish enters as the chief article1 is ill adapted to strengthen mind or body1 while its continued use is said to be the fertile source of nearly every form of disease of the skin4 ,some persons are so constituted that they can eat no kind of fish without experiencing unpleasant results4 ,sidenote3 #bc4 ,list of vegetable articles8 ,usefulness of the different vegetables8 ,strychnia8 ,what further is said in relation to the nourishing and other qualities of vegetables8 #bc4 ,,vegetable ,,food4--,the list of vegetable articles of diet is a very long one1 including the grains from which our bread-stuffs are made1 the vegetables from the garden1 and the fruits4 ,all the products of the vegetable kingdom are not alike useful4 ,some are positively hurtful2 indeed1 the most virulent poisons1 as strychnia and prussic acid1 are obtained from certain vegetables4 ,again1 of such #gb articles as have been found good for food1 some are more nourishing than others3 some require very little preparation for use1 while others are hard and indigestible1 and can only be used after undergoing many preparatory processes4 ,great care must therefore be exercised1 and many experiments made1 before we can arrive at a complete knowledge in reference to these articles of diet4 ,tea1 coffee1 and other substances from which drinks are made1 are of vegetable origin4 ,sidenote3 #bd4 ,wheat8 ,staff of life8 ,white flour8 ,hard-grain wheats8 ,bolting8 ,graham bread8 #bd4 ,,bread4--,wheat is the principal and most valuable kind of grain for the service of man4 ,bread made from wheat-flour has been in use for many hundreds of years1 and on this account1 as well as because of its highly nourishing properties1 has been aptly called the staff of life4 ,we never become tired of good bread as an article of daily food4 ,the white kinds of flour contain more starch and less gluten than the darker1 and are therefore less nutritious4 ,the hard-grain wheat yields the best flour4 ,in grinding wheat1 the chaff or bran is separated by a process called bolting4 ,unbolted flour is used for making brown or ,graham bread4 ,sidenote3 #be4 ,leavened bread8 ,unleavened8 ,hot bread8 #be4 ,the form of bread most easily digested is that which has been leavened1 or rendered porous by the use of yeast1 or by some similar method4 ,unleavened bread requires much more mastication4 ,hot bread is unwholesome1 because it is not firm enough to be thoroughly masticated1 but is converted into a pasty1 heavy mass that is not easily digested4 ,sidenote3 #bf4 ,wheaten bread8 ,bread and butter8 ,experiment on the dog8 #bf4 ,wheaten bread contains nearly every principle requisite for sustaining life1 except fat4 ,this is commonly added in other articles of diet1 especially in butter1--bread and butter1 consequently1 forming an almost perfect article of #gc food4 ,the following experiment is recorded3 ,a dog eating ad libitum of white bread1 made of pure wheat1 and freely supplied with water1 did not live beyond fifty days4 ,he died at the end of that time with all the signs of gradual exhaustion4 ,death took place1 not because there was anything hurtful in the bread1 but because of the absence of one or more of the food-principles4 ,sidenote3 #bg4 ,state what is said of the ,irish potato8 #bg4 ,,the ,,potato4--,the common or ,irish potato is the vegetable most extensively used in this country and ,great ,britain4 ,among the poorer classes in ,ireland it is the main article of food4 ,while it is not so rich in nutritious substances as many others1 it has some very useful qualities4 ,it keeps well from season to season1 and men do not weary of its continuous use4 ,it is more than two-thirds water1 the balance being chiefly starch1 with a little albumen4 ,sidenote3 #bh4 ,sweet potato8 ,nightshades8 ,potatoes when germinating8 #bh4 ,the sweet potato differs from the white or common1 in containing more water and a small proportion of sugar4 ,the common potato and the tomato belong to the same botanical order as the nightshades1 but do not possess their poisonous qualities1 unless we except potatoes that are in the process of germination or sprouting1 when they are found injurious as food4 ,sidenote3 #bi4 ,fruits8 ,use of ripe fruit8 ,nutriment they contain8 ,starch in unripe fruits8 ,cooking of unripe fruits8 #bi4 ,,fruits4--,these are produced1 in this country1 in great abundance1 and are remarkable alike for their variety and delicious flavor2 consequently they are consumed in large quantities1 especially during the warmer months4 ,the moderate use of ripe fruits1 in their season1 is beneficial1 because they offer a pleasant substitute for the more concentrated diet that is used in cold weather4 ,the amount of solid nutriment they contain is1 however1 small4 ,the percentage of water in cherries is seventy-five1 in grapes eighty-one1 in apples eighty-two4 ,unripe fruits contain starch1 which1 during the process of ripening1 #gd is converted into sugar4 ,such fruits are indigestible and should be avoided3 cooking1 however1 in part removes the objections to them4 ,sidenote3 #cj4 ,how should drinking-water be as regards color and smell8 ,chemically pure water8 ,how obtained8 ,agreeableness of perfectly pure water8 #cj4 ,,pure ,,water4--,it is important that the water we drink and use in the preparation of food should be pure4 ,it should be clear and colorless1 with little or no taste or smell1 and free from any great amount of foreign ingredients4 ,chemically pure water does not occur in nature3 it is only obtained by the condensation of steam1 carefully conducted1 and is not as agreeable for drinking purposes as the water furnished by springs and streams4 ,rain-water is the purest occurring in nature2 but even this contains certain impurities1 especially the portion which falls in the early part of a shower2 for in its descent from the clouds1 the particles floating in the air are caught by the falling drops4 ,sidenote3 #ca4 ,spring and well water8 ,whence the sparkle1 or life8 ,the water supply of cities8 ,croton water8 ,ridgewood8 #ca4 ,water from springs and wells always contains more or less foreign matter of mineral origin4 ,this imparts to the drink its pleasant taste--the sparkle1 or life1 coming from the gases absorbed by the water during its passage under ground4 ,the ordinary supply of cities is from some pure stream or pond conveyed from a distance through pipes1 the limpid fluid containing generally only a small amount of impurity4 ,croton water1 the supply of ,new ,york ,city1 is very pure1 and contains only four and a half grains to a gallon3 the ,ridgewood water of ,brooklyn holds even less foreign matter4 ,sidenote3 #cb4 ,impurities in drinking-water8 ,mineral springs8 #cb4 ,drinking-water may contain as large a proportion as sixty to seventy grains per gallon of impurity1 but a much larger quantity renders it unwholesome4 ,the mineral spring waters1 used popularly as medicines1 are highly charged with mineral substances4 ,some of them1 such as #ge the waters at ,saratoga1 contain three hundred grains and more to the gallon4 ,sidenote3 #cc4 ,what is stated of the action of water upon lead8 #cc4 ,,action ,,of ,,water ,,upon ,,lead4--,the danger of using water that has been in contact with certain metals is well known4 ,lead is one of the most readily soluble1 and probably the most poisonous of these substances in common use4 ,when pure water and an untarnished surface of lead come in contact1 the water gradually corrodes the metal1 and soon holds an appreciable quantity of it in solution4 ,when this takes place the water becomes highly injurious3 the purer the water1 and the more recent the use of the metal1 the greater will be the danger4 ,sidenote3 #cd4 ,lead in pipes and other things8 ,advice8 ,what takes place after the articles of lead have been used much8 ,what is wise8 #cd4 ,in cities1 lead pipes are commonly used to convey water through the houses2 lead being also used in the construction of roofs1 cisterns1 and vessels for keeping water and other liquids4 ,after the articles of lead have been in use several months1 the danger of lead-poisoning diminishes4 ,an insoluble coating of the sulphate of lead forms upon the exposed surface1 thus protecting it from further corrosion4 ,it is1 however1 a wise precaution1 at all times to reject the water or other fluid that has been in contact with leaden vessels over night1 or for a number of hours4 ,allow the water in pipes to run freely before using4 ,sidenote3 #ce4 ,coffee as an article of diet8 ,of what does it consist8 ,how does the water affect the coffee8 ,the peculiar stimulant8 ,how does it affect most persons8 #ce4 ,,coffee4--,this is an important addition to diet1 and if moderately used is beneficial to persons of adult age4 ,as commonly employed1 it consists of an infusion in boiling water of the roasted and ground berry4 ,the water extracts certain flavoring and coloring matters1 but that which gives it its peculiar stimulant qualities is the alkaloid caffein4 ,with most persons its action is that of a gentle stimulant1 without any injurious reaction4 ,it produces a restful feeling after exhausting efforts of mind or #gf body2 it tranquilizes1 but does not disqualify for labor2 and hence it is highly esteemed by persons of literary pursuits4 ,sidenote3 #cf4 ,another property of coffee8 ,miners of ,belgium8 ,the ,caravans8 ,among armies8 ,taken with meals8 #cf4 ,another property of coffee is1 that it diminishes the waste of the tissues1 and consequently permits the performance of excessive labor upon an economical and inadequate diet4 ,this has been tested among the miners of ,belgium4 ,their allowance of solid food was below that found necessary in prisons and elsewhere2 but1 with the addition of about four pints of coffee daily1 they were enabled to undergo severe labor without reducing their muscular strength4 ,the caravans which traverse the deserts are supported by coffee during long journeys and lengthened privation of food4 ,among armies it is indispensable in supplementing their imperfect rations1 and in relieving the sense of fatigue after great exposure and long marches4 ,when taken with meals1 coffee is also thought to promote digestion4 ,sidenote3 #cg4 ,effects of tea-drinking8 ,peculiar principle8 ,the tea beverage1 how made8 ,black and green tea8 ,excessive use of tea or coffee8 #cg4 ,,tea4--,the effects of tea-drinking are very similar to those of coffee1 and are due to a peculiar principle called thein4 ,this principle is probably the same as that found in coffee1 caffein1 since the chemical composition of both is precisely alike4 ,tea1 as a beverage1 is made from the dried leaves of the plant by the addition of hot water2 if the tea is boiled1 the oil which gives it its agreeable flavor is driven off with the steam4 ,there are two kinds of tea--the black and the green3 the latter is sometimes injurious1 producing wakefulness and other nervous symptoms4 ,the excessive use of either coffee or tea will cause wakefulness4 ,sidenote3 #ch4 ,experiments made during ,kane's expedition8 #ch4 ,during ,dr4 ,kane's expedition in the ,arctic regions1 the effects of these articles were compared4 ,after #gg repeated trials1 the men took most kindly to coffee in the morning and tea in the evening4 ,the coffee seemed to continue its influence throughout the day1 and they seemed to grow hungry less rapidly than after drinking tea1 while tea soothed them after a day's hard labor1 and the better enabled them to sleep4 ,they both operated upon fatigued men like a charm1 and their superiority over alcoholic stimulants was very decided4 ,sidenote3 #ci4 ,state what is said of chocolate4 #ci4 ,chocolate is made from the seeds of the cocoa-tree1 a native of tropical ,america4 ,its effects resemble somewhat those of tea and coffee1 but it is very rich in nutriment4 ,linnus1 the botanist1 was so fond of this beverage1 that he gave to the cocoa-tree the name1 ,theobroma--the ,food of the ,gods4 ,its active principle is theobromin4 ,sidenote3 #dj4 ,use of alcoholic drinks1 how general8 ,the rule given8 #dj4 ,,alcohol4--,the list of beverages that are consumed for the sake of the alcohol they contain is a very long one4 ,their use is almost universally prevalent1 every civilized nation1 and nearly every barbarous one1 having its favorite alcoholic drink2 and1 as a general rule1 the nations which stand the highest in civilization have the greatest varieties of these beverages1--at the same time using them the most intelligently and wisely4 ,sidenote3 #da4 ,the beverages produced by fermentation8 ,the ardent spirits8 ,grains and fruits employed8 ,long use of wine8 ,of distilled liquors8 #da4 ,the wines and malt liquors that contain a small amount of alcohol are produced by fermentation4 ,the beverages that hold a large proportion of alcohol1 the ardent spirits1 are made by distillation4 ,enormous quantities of grains and fruits are thus yearly diverted from their proper uses as food2 some of these being corn1 wheat1 rye1 barley1 potatoes1 and rice2 also the grape1 apple1 pear1 peach1 sugar-cane1 cherry1 fig1 and orange4 ,wine1 the fermented juice of the grape1 has been in use from time immemorial1 while the introduction of distilled liquors dates from a comparatively recent period4 #gh ,sidenote3 #db4 ,describe the action of alcohol upon the human system8 ,experience of ,dr4 ,hayes and others8 #db4 ,what is the physiological action of alcohol8 ,its first and most evident action is stimulation3 this effect is transient1 and is followed by a variable degree of depression4 ,at first it sharpens the appetite and quickens digestion1 but its habitual use impairs both4 ,this stimulation is efficient in giving the system an artificial strength during some temporary derangement1 and in enabling the endurance of unusual fatigue or exposure4 ,the experience of ,dr4 ,hayes1 and other explorers of the polar regions1 is that alcohol does not enable the body to resist the influence of cold1 but1 on the contrary1 is always injurious4 ,sidenote3 #dc4 ,another property of alcohol8 ,how do we explain the restorative influence of wines and liquors8 #dc4 ,another property it has in common with tea and coffee4 ,it supports the powers of life1 economizes food1 and retards the waste of tissues2 in other words1 it banks the fires1 and prevents their burning wastefully4 ,on this principle we explain the restorative influence of wines or liquors during exhausting diseases1 in convalescence1 and after excessive labors of mind or body4 ,sidenote3 #dd4 ,alcohol1 a poison8 ,moderate stimulants8 ,prevailing opinion8 ,hence8 #dd4 ,pure alcohol1 or an excessive quantity of ardent spirits1 is an undoubted poison1 and has been frequently known to produce fatal results4 ,stimulants in moderate quantities have been thought to increase strength1 and in this view they have been called alcoholic foods4 ,this is not now conceded by scientific men4 ,the prevailing opinion is1 that they serve no useful purpose as an article of diet1 and that their beneficial influence is limited to cases where the system is enfeebled1 where some unnatural demand is made upon the vital powers1 or where the supply of food is insufficient4 ,hence1 while alcohol has not the power to build up1 it may obstruct the process of pulling down4 #gi ,,questions ,,for ,,topical ,,review4 ,,page #a4 ,how is the necessity for food shown8 #fd #b4 ,to what process of waste and repair is the body constantly subjected8 #fd #c4 ,how do you account for the sensations of hunger and thirst8 #fe #d4 ,what further can you state having relation to the subject8 #fe #e4 ,what can you state in regard to the quantity of food required for the support of life8 #fe1 #ff #f4 ,what circumstances change the needs of persons1 old and young1 as regards food and drink8 #fe1 #fg #g4 ,what becomes of all the food and drink we consume8 #ff #h4 ,what further can you state in relation to the process of renovation through which the body passes8 #ff #i4 ,what can you state of the habits of nations in respect to diet8 #ff1 #fg1 #fi #aj4 ,what in relation to the selection of articles for food8 #fg #aa4 ,what as respects the necessity for changing or varying the diet8 #fg #ab4 ,what has been proved as regards animal food8 #fg #ac4 ,of what importance is milk as an article of food8 #fg1 #fh #ad4 ,what are the constituents of milk8 #fh #ae4 ,what can you state of eggs as an article of food8 #fh #af4 ,of the meats1 so called1 as an article of food8 #fh1 #fi #ag4 ,what effect does cold have upon meats8 #fi #ah4 ,in what other way may beef and pork be preserved8 #fi #ai4 ,what can you state of salted meat as food1 and of its continued use8 #fi #bj4 ,what change does meat undergo in the cooking8 #gj1 #ga #ba4 ,what directions are given for boiling meat8 #gj #bb4 ,what for roasting1 and with what results8 #gj1 #ga #bc4 ,what is said about the frying of meats8 #ga #bd4 ,give the statement in relation to trichina4 #ga #be4 ,state what is said in relation to fish4 #ga #bf4 ,what is stated of the usefulness and other properties of the products of the vegetable kingdom8 #ga1 #gb #bg4 ,what further is said of vegetable food8 #ga1 #gb #bh4 ,why is bread made of wheat flour so important as an article of food8 #gb #bi4 ,state whatever else you can in relation to bread4 #gb1 #gc #cj4 ,give the statement respecting the potato4 #gc #ca4 ,what is stated of fruits1 the use of them1 their nutritious qualities1 etc48 #gc1 #gd #cb4 ,how general is the existence of perfectly pure water8 #gd #cc4 ,what is stated in relation to drinking water8 #gd1 #ge #cd4 ,how does the action of water upon lead affect lead8 #ge #ce4 ,what further can you state on the subject8 #ge #cf4 ,what properties has coffee as an article of diet8 #ge1 #gf #cg4 ,in what circumstances has coffee been found peculiarly beneficial8 #gf #ch4 ,what comparison is made between coffee1 tea1 and chocolate8 #gf #ci4 ,how are the wines1 and malt and other alcoholic beverages produced8 #gg #dj4 ,what articles are employed in their production8 #gg #da4 ,describe the physiological action of alcohol4 #gh #db4 ,what comparison is made between tea1 coffee1 and alcohol8 #gh #dc4 ,what can you state of alcohol1 as a poison1 a stimulant1 and article of diet8 #gh #dd4 ,what1 then1 can be said of alcohol as a recommendation8 #gh 99 99 99 99 99 #hj ,,chapter ,,vi4 ,,digestion4 ,the ,principal ,processes of ,nutrition--,the ,general ,plan of ,digestion--,mastication--,the ,teeth--,preservation of the ,teeth--,insalivation--,the ,stomach and the ,gastric ,juice--,the ,movements of the ,stomach--,gastric ,digestion--,the ,intestines--,the ,bile and ,pancreatic ,juice--,intestinal ,digestion--,absorption by means of ,blood-vessels and ,lacteals--,the ,lymphatic or ,absorbent ,system--,the ,lymph--,conditions which affect ,digestion--,the ,quality1 ,quantity1 and ,temperature of the ,food--,the ,influence of ,exercise and ,sleep4 ,sidenote3 #a4 ,design of food8 ,how accomplished8 #a4 ,,nutrition4--,the great design of food is to give nutriment or nourishment to the body4 ,but this is not accomplished directly1 as the food must first pass through certain preparatory changes1 as follows3 7#a71 ,digestion1 by which the food is reduced to a soluble condition2 7#b71 ,absorption1 by which1 when digested1 it is imbibed into the blood2 7#c71 ,circulation1 which carries the enriched blood to the various parts of the system2 and 7#d71 ,assimilation1 by which each tissue derives from the blood the materials necessary for its support4 ,sidenote3 #b4 ,sustaining power of food8 ,simile of the engine8 ,operation in the human body8 #b4 ,by these means the sustaining power of food is gradually developed and employed1 and the vital machinery kept in working order1 somewhat after the manner of the steam-engine4 ,to operate the latter1 the force imprisoned within the coal and water is set free and converted into motion by the combustion of the fuel and the vaporization of the water4 ,it will be seen1 however1 when we come to study these operations in the human body1 that they are conducted silently and harmoniously1 with marvellous delicacy and completeness1 and without that friction1 and #ha consequent loss of power1 which attend the working of the most perfect machinery of man's invention4 ,sidenote3 #c4 ,change of food in digestion8 ,process of digestion8 ,describe the alimentary canal4 #c4 ,,general ,,plan ,,of ,,digestion4--,the great change which food undergoes in digestion is essentially a reforming process1 reducing articles of diet1 which are at first more or less solid1 crude1 and coarse1 to a liquid and finely comminuted condition1 suitable for absorption into the blood4 ,the entire process of digestion takes place in what is called the alimentary canal1 a narrow1 tortuous tube1 about thirty feet in its entire length4 ,this canal begins in the mouth1 extends thence downward through the gullet to the stomach 7a receptacle in which the principal work of digestion is performed71 and thence onward through the small and large intestines4 ,illustration3 ,,fig4 #af4--,,section ,,of ,,the ,,trunk ,,showing ,,the ,,cavities ,,of ,,the ,,chest ,,and ,,abdomen4 ,a1 ,cavity of ,chest2 ,b1 ,diaphragm2 ,c1 ,abdomen2 ,d1 ,e1 ,spinal ,column4 ,sidenote3 #d4 ,situation of the stomach and intestines8 ,action of the food8 ,mechanical action8 ,chemical8 #d4 ,the stomach and intestines are situated in the cavity of the abdomen 7,fig4 #af1 ,c1 and ,fig4 #bb71 and occupy about two-thirds of its space4 ,the action to which the food is subjected in these organs is of two kinds--mechanical and chemical4 ,by the former it is crushed1 agitated1 and carried onward from one point to another2 by the latter it is changed in form through the solvent power of the various digestive juices4 #hb ,sidenote3 #e4 ,describe the process of mastication8 ,how many and what movements8 #e4 ,,mastication4--,as soon as solid food is taken into the mouth1 it undergoes mastication1 or chewing4 ,it is caught between the opposite surfaces of the teeth1 and by them is cut and crushed into very small fragments4 ,in the movements of chewing1 the lower jaw plays the chief part2 the upper jaw1 having almost no motion1 acts simply as a point of resistance1 to meet the action of the former4 ,these movements of the lower jaw are of three sorts3 a vertical or cutting1 a lateral or grinding1 and a to-and-fro or gnawing motion4 ,illustration3 ,,fig4 #ag4--,,section ,,of ,a ,,tooth4 a1 ,enamel2 b1 ,cavity2 c c1 ,roots2 d1 ,body of the ,tooth4 ,sidenote3 #f4 ,composition of the teeth8 ,enamel of the teeth8 ,interior of teeth8 #f4 ,the teeth are composed of a bone-like material1 and are held in place by roots running deeply into the jaw4 ,the exposed portion1 or crown1 is protected by a thin layer of enamel 7,fig4 #ag1 a71 the hardest substance in the body1 and1 like flint1 is capable of striking fire with steel4 ,in the interior of each tooth is a cavity1 containing blood-vessels and a nerve1 which enter it through a minute opening at the point of the root 7,fig4 #ai74 ,sidenote3 #g4 ,the milk teeth8 ,the permanent teeth8 #g4 ,there are two sets of teeth2 first1 those belonging to the earlier years of childhood1 called the milk teeth1 which are twenty in number and small4 ,at six or eight years of age1 when the jaw expands1 and when the growing body requires a more powerful and numerous set1 the roots of #hc the milk teeth are absorbed1 and the latter are shed1 or fall out1 one after another 7,fig4 #ah71 to make room for the permanent set4 ,illustration3 ,,fig4 #ah4--,,section ,,of ,,the ,,jaws4 #a' #b' #c' #d' #e'1 ,the ,milk ,teeth2 #a to #h1 ,the ,germs of the ,permanent ,set4 ,sidenote3 #h1 #i4 ,number of teeth8 ,how distributed8 #h4 ,there are thirty-two teeth in the permanent set1 as many being in one jaw as the other4 ,each half-jaw has eight teeth1 similarly shaped and arranged in the same order3 thus1 two incisors1 one canine1 two bicuspids1 and three molars4 ,the front teeth are small1 sharp1 and chisel-edged1 and are well adapted for cutting purposes2 hence their name incisors4 ,the canines stand next1 one on each side of the jaw2 these receive their name from their resemblance to the long1 pointed tusks of the dog 7,fig4 #ai74 #hd ,illustration3 ,,fig4 #ai4--,,section ,,of ,,the ,,jaws--,,right ,,side4 ,v1 ,a1 ,n1 ,veins1 ,arteries1 and ,nerves of the ,teeth4 ,the root of one tooth in each jaw is cut vertically to show the cavity and the blood-vessels1 etc41 within it4 #a to #h1 ,permanent ,teeth4 #i4 ,the bicuspids1 next in order1 are larger and have a broader crown than the former2 while behind them are the molars1 the largest and most powerful of the entire set4 ,these large back teeth1 or grinders1 present a broad1 rough surface1 suitable for holding and crushing the food4 ,the third molar1 or wisdom tooth1 is the last to be cut1 and does not appear until about the twenty-first year4 #he ,the order of arrangement of the teeth is indicated by the following dental formula3-- ,illustration ,sidenote3 #aj4 ,different forms of teeth8 ,human teeth8 ,the inference8 #aj4 ,it is interesting1 at this point1 to notice the different forms of teeth in different animals1 and observe how admirably their teeth are suited to the respective kinds of food upon which they subsist4 ,in the carnivora1 or flesh-feeders1 the teeth are sharp and pointed1 enabling them both to seize their prey1 and tear it in pieces2 while the herbivora1 or vegetable-feeders1 have broad1 blunt teeth1 with rough crowns1 suitable for grinding the tough grasses and grains upon which they feed4 ,human teeth partake of both forms2 some of them are sharp1 and others are blunt2 they are therefore well adapted for the mastication of both flesh and vegetables4 ,hence we argue that1 although man may live exclusively upon either vegetable or animal food1 he should1 when possible1 choose a diet made up of both varieties4 ,sidenote3 #aa4 ,cleaning of teeth8 ,effects of not cleaning8 #aa4 ,,preservation ,,of ,,the ,,teeth4--,in order that the teeth shall remain in a sound and serviceable condition1 some care is of course requisite4 ,in the first place1 they require frequent cleansing2 for every time we take food1 some particles of it remain in the mouth2 and these1 on account of the heat and moisture present1 soon begin to putrefy4 ,this not only renders the breath very offensive1 but promotes decay of the teeth4 #hf ,sidenote3 #ab4 ,effects upon the saliva8 ,formation of tartar8 ,how prevented8 ,how destroyed8 #ab4 ,the saliva1 or moisture of the mouth1 undergoes a putrefactive change1 and becomes the fertile soil in which a certain minute fungus has its growth4 ,this fluid1 too1 if allowed to dry in the mouth1 collects upon the teeth in the form of an unsightly1 yellow concretion1 called tartar4 ,to prevent this formation1 and to remove other offensive substances1 the teeth should be frequently cleaned with water1 applied by means of a soft tooth-brush4 ,the destruction of the tartar fungus is best effected by the use of a weak solution of carbolic acid4 ,sidenote3 #ac4 ,destruction of the enamel8 ,how guarded against8 #ac4 ,again1 it should be borne in mind that the enamel1 ,nature's protection for the teeth1 when once destroyed1 is not formed anew2 and the body of the tooth thus exposed1 is liable to rapid decay4 ,on this account1 certain articles are to be guarded against2 such as sharply acid substances that corrode the enamel1 and hard substances that break or scratch it--as gritty tooth powders1 metal tooth picks1 and the shells of hard nuts4 ,sudden alternations from heat to cold1 when eating or drinking1 also tend to crack the enamel4 ,sidenote3 #ad4 ,mixing of food with the saliva8 ,what is the saliva8 ,how secreted8 ,the salivary glands8 #ad4 ,,insalivation4--,when the morsel of food is cut and ground by the teeth1 it is at the same time also intimately mixed with the saliva1 or fluids of the mouth4 ,this constitutes the second step of digestion1 and is called insalivation4 ,the saliva1 the first of the digestive solvents1 is a colorless1 watery1 and frothy fluid4 ,it is secreted 7i4 e4 separated from the blood7 partly by the mucous membrane which lines the mouth2 but chiefly by the salivary glands1 of which there are three pairs situated near the mouth4 ,sidenote3 #ae4 ,the flow of saliva8 ,the thought of food8 ,anxiety and grief8 ,animals fed upon dry and coarse food8 #hg #ae4 ,these glands consist of clusters of very small pouches1 around which a delicate network of blood-vessels is arranged3 they empty into the mouth by means of little tubes1 or ducts4 ,the flow from these glands is at all times sufficient to maintain a soft and moist condition of the tongue and mouth2 but when they are excited by the presence and taste of food1 they pour forth the saliva more freely4 ,even the mere thought of food will at times cause the saliva to flow1 as when the appetite is stimulated by the sight or smell of some savory article2 so that the common expression is correct that the mouth waters for the favorite articles of food4 ,anxiety and grief prevent its flow1 and cause the tongue to cleave to the roof of the mouth4 ,in the horse and other animals1 that feed upon dry and coarse fodder1 and require an abundant supply of saliva1 we find large salivary glands1 as well as powerful muscles of mastication4 ,illustration3 ,,fig4 #bj4--,,structure ,,of ,a ,,salivary ,,gland4 ,illustration3 ,,fig4 #ba4--,,the ,,head ,,of ,a ,,horse1 showing the large salivary gland 7a71 its duct 7b71 the muscles of mastication 7c1 d1 e1 f1 and g74 ,sidenote3 #af4 ,importance of the process8 ,the first place8 ,the second8 ,the third8 #af4 ,the mingling of the saliva with the food seems a simple process1 but it is one that plays an important part #hh in digestion4 ,in the first place1 it facilitates the motions of mastication1 by moistening the food and lubricating the various organs of the mouth4 ,secondly1 it prepares the way for other digestive acts3 by the action of the teeth1 the saliva is forced into the solid food1 softens the harder substances1 and assists in converting the whole morsel into a semi-solid1 pulpy mass1 that can be easily swallowed1 and readily permeated by other digestive fluids4 ,the saliva also1 by dissolving certain substances1 as sugar and salt1 develops the peculiar taste of each2 whereas1 if the tongue be dry and coated1 they are tasteless4 ,hence1 if substances are insoluble1 they are devoid of taste4 ,sidenote3 #ag4 ,its final importance8 ,starch8 ,how effected8 ,ptyalin8 #ag4 ,finally1 the saliva has the property of acting chemically upon the food4 ,as we have before stated 7,chap4 ,,iv471 starch1 as starch1 cannot enter the tissues of the body2 but1 in order to become nutriment1 must first be changed to grape sugar4 ,this change is1 in part1 effected by the saliva1 and takes place almost instantly1 whenever it comes in contact with cooked starch4 ,this important function is due to an organic ingredient of the saliva called ptyalin4 ,this substance has been extracted from the saliva by the chemist1 and has been found1 by experiment1 to convert into sugar two thousand times its own weight of starch4 ,sidenote3 #ah4 ,each of the processes8 ,why is a knowledge of the digestive functions important8 ,how shown8 #ah4 ,,importance ,,of ,,mastication ,,and ,,insalivation4--,each of these processes complements the other1 and makes the entire work available2 for1 by their joint action1 they prepare the food in the best possible manner for further digestive changes4 ,the knowledge of these preliminary functions will appear the more important1 when we reflect that they are the only ones which we can regulate by the will4 ,for1 as soon as the act of swallowing begins1 the food not only passes out of sight1 but beyond #hi control2 and the subsequent acts of digestion are consequently involuntary and unconsciously performed4 ,sidenote3 #ai4 ,rapid eating8 ,describe the process and effects4 #ai4 ,it is generally known that rapid eating interferes with digestion4 ,how does this occur8 ,in the first place1 in rapid eating1 the flow of the saliva is insufficient to moisten the solid parts of the food1 so that they remain too hard and dry to be easily swallowed4 ,this leads to the free and frequent use of water1 or some other beverage1 at meals1 to wash down the food1--a most pernicious practice4 ,for these fluids1 not only cannot take the place of the natural digestive juices1 but1 on the contrary1 dilute and weaken them4 ,sidenote3 #bj4 ,loss of taste8 ,another effect of rapid eating8 ,mistakes8 #bj4 ,secondly1 the saliva being largely the medium of the sense of taste1 the natural flavors of the food are not developed1 and consequently it appears comparatively insipid4 ,hence the desire for high-seasoned food1 and pungent sauces1 that both deprave the taste and over excite the digestive organs4 ,rapid eating also permits the entrance of injurious substances which may escape detection by the taste1 and be unconsciously received into the system4 ,in some instances1 the most acrid and poisonous substances have frequently been swallowed by mistake1 before the sense of taste could act1 and demand their rejection4 ,sidenote3 #ba4 ,effect of imperfectly broken food in the stomach8 ,dyspepsia8 ,overeating8 #ba4 ,thirdly1 the food1 being imperfectly broken up by the teeth1 is hurried onward to the stomach1 to be by it more thoroughly divided4 ,but the task thus imposed upon the stomach1 it is not at all adapted to perform2 so that the crude masses of food remain a heavy burden within the stomach1 and a source of distress to that organ1 retarding the performance of its legitimate duty4 ,hence persons who habitually eat too rapidly1 frequently fall victims to dyspepsia4 ,rapid eating also conduces to overeating4 ,the food is introduced so rapidly1 that the system has not #ij time to recognize that its real wants are met1 and that its losses have been made good2 and hence the appetite continues1 although more nutriment has been swallowed than the system requires1 or can healthfully appropriate4 ,illustration3 ,,fig4 #bb4--,,section ,,of ,,chest ,,and ,,abdomen4 ,a1 ,heart4 ,b1 ,the ,lungs4 ,c1 ,stomach4 ,d1 ,the ,liver4 ,e1 ,large ,intestine4 ,g1 ,small ,intestine4 ,sidenote3 #bb4 ,gullet8 ,describe the stomach and its location4 ,effects of gormandizing8 #bb4 ,,the ,,stomach4--,as soon as each separate portion of food is masticated and insalivated1 it is swallowed2 that is1 it is propelled downward to the stomach1 through a narrow muscular tube about nine inches in length1 called the oesophagus1 or gullet 7,fig4 #bc74 ,the stomach is the only large expansion of the digestive canal1 and is the most important organ of digestion4 ,it is a hollow1 pear-shaped pouch1 having a capacity of three pints1 in the adult4 ,its walls are thin and yielding1 and may become unnaturally distended1 as in the case of those who subsist on a bulky1 innutritious diet1 and of those who habitually gormandize4 ,sidenote3 #bc4 ,heart-orifice8 ,gatekeeper8 ,coins1 etc48 ,indication of the soft and yielding texture of the stomach8 #bc4 ,the stomach has also two openings2 that by which food enters1 being situated near the heart1 is called the cardiac1 or heart orifice2 the other is the pylorus1 or gatekeeper1 which guards the entrance to the intestines1 #ia and1 under ordinary circumstances1 permits only such matters to pass it as have first been properly acted upon in the stomach4 ,coins1 buttons1 and the like are1 however1 readily allowed to pass1 because they can be of no use if retained4 ,the soft and yielding texture of this organ--the stomach--indicates that it is not designed to crush and comminute solid articles of food4 ,illustration3 ,,fig4 #bc4--,,the ,,organs ,,of ,,digestion4 ,o1 ,oesophagus4 ,s1 ,stomach4 ,l1 ,liver4 ,m1 ,pylorus4 ,c1 ,large ,intestines4 ,p1 ,pancreas4 ,i1 ,small ,intestines4 ,n1 ,spleen4 ,g1 ,gall-bladder4 ,sidenote3 #bd4 ,what is meant by the gastric juice8 #bd4 ,,the ,,gastric ,,juice4--,we have seen how the presence of food in the mouth excites the salivary glands1 causing the saliva quickly to flow4 ,in the same manner1 when food reaches the stomach1 its inner lining1 the mucous membrane1 is at once excited to activity4 7,at first its surface1 which while the stomach is empty presents a pale pink hue1 turns to a bright red color1 for the minute blood-vessels which course through it1 are filled with blood4 ,presently a clear1 colorless1 and acid fluid exudes1 drop by drop1 from its numerous minute glands or tubules1 until finally the surface is moistened in every part1 and the fluid begins to mingle with the food4 ,this fluid is termed the gastric juice4 #ib ,sidenote3 #be4 ,what is the office of the gastric juice8 ,acidity of the gastric juice8 ,quantity of gastric juice used8 ,what becomes of it8 #be4 ,the gastric juice is the proper solvent of certain articles of food1 especially those belonging to the albuminoid class4 ,this solvent power is due to its peculiar ingredient1 pepsin2 in digestion1 this substance acts like a ferment2 that is1 it induces changes in the food simply by its presence1 but does not itself undergo change4 ,the acidity of the gastric juice1 which is due to lactic acid1 is not accidental2 for we find that the pepsin cannot act in an alkaline solution--that is1 one which is not acid or neutral4 ,the quantity of gastric juice secreted daily is very large1 probably not less than three or four pints at each meal4 ,though this fluid is at once used in the reduction of the food1 it is not lost2 since it is soon re-absorbed by the stomach1 together with those parts of the food which it has digested and holds in solution4 ,sidenote3 #bf4 ,muscular coat of the stomach8 ,expansion and contraction of its fibres8 ,action of the fibres8 #bf4 ,,movements ,,of ,,the ,,stomach4--,the inner coating of the stomach is the mucous membrane1 which1 as we have seen1 furnishes the gastric juice4 ,next to this coating lies another1 called the muscular coat1 composed of involuntary muscular fibres1 some of which run circularly1 and others in a longitudinal direction4 ,these expand to accommodate the food as it is introduced1 and contract as it passes out4 ,in addition1 these fibres are in continual motion while food remains in the stomach1 and they act in such manner that the contents are gently turned round from side to side1 or from one end of it to the other4 ,sidenote3 #bg4 ,peristaltic movements8 ,what is said of our consciousness of and power over these movements8 ,describe the movements of the pylorus4 #bg4 ,by these incessant movements of the stomach1 called the peristaltic movements1 the gastric juice comes in contact with all parts of the food4 ,we are1 however1 not conscious that these movements take place1 nor have we the power to control them4 ,when such portions of the food as are sufficiently digested approach the pylorus1 it #ic expands to allow them to pass out1 and it closes again to confine the residue for further preparation4 ,sidenote3 #bh4 ,how has the knowledge and the workings of the stomach been ascertained8 ,st4 ,martin8 ,how else8 #bh4 ,the knowledge of these and other interesting and instructive facts has been obtained by actual observation2 the workings of the stomach of a living human being have been laid open to view and examined--the result of a remarkable accident4 ,alexis ,st4 ,martin1 a ,canadian voyageur1 received a gun-shot wound which laid open his stomach1 and which1 in healing1 left a permanent orifice nearly an inch in diameter4 ,through this opening the observer could watch the progress of digestion1 and experiment with different articles of food4 ,since that occurrence1 artificial openings into the stomach of the inferior animals have been repeatedly made1 so that the facts of stomach-digestion are very well ascertained and verified4 ,sidenote3 #bi4 ,what was formerly thought8 ,what do we now know8 ,what else do we now know8 ,water1 salt1 and sugar8 ,absorption8 #bi4 ,,gastric ,,digestion4--,what portions of the food are digested in the stomach8 ,it was formerly thought that all the great changes of digestion were wrought here1 but later investigation has taught us better4 ,we now know that the first change in digestion takes place in the mouth1 in the partial conversion of starch into sugar4 ,we also know that1 of the three organic food principles 7considered in ,chapter ,,iv47 two--the fats and the sugars--are but slightly affected by the stomach2 but that its action is confined to that third and very important class1 from which the tissues are renewed1 the albuminoids4 ,a few articles need no preparation before entering the system1 as water1 salt1 and grape-sugar4 ,these are rapidly taken up by the blood-vessels of the stomach1 which everywhere underlie its mucous membrane in an intricate and most delicate network4 ,in this way the function of absorption begins4 ,sidenote3 #cj4 ,albuminose8 ,the process8 ,chyme8 #cj4 ,the albuminoid substances are speedily attacked and #id digested by the gastric juice4 ,from whatever source they are derived1 vegetable or animal1 they are all transformed into the same digestive product1 called albuminose4 ,this is very soluble in water1 and is readily absorbed by the blood-vessels of the stomach4 ,after a longer or shorter time1 varying from one to five hours1 according to the individual and the quantity and quality of his food1 the stomach will be found empty4 ,not only has the digested food passed out1 but also those substances which the stomach could not digest or absorb have passed little by little through the pylorus1 to undergo further action in the intestines4 ,at the time of its exit1 the digested food is of a pulpy consistence1 and dark color1 and is then known as the chyme4 ,sidenote3 #ca4 ,what are the intestines8 ,the small intestines8 ,the large intestines8 ,their structure8 #ca4 ,,the ,,intestines4--,the intestines1 or bowels1 are continuous with the stomach1 and consist of a fleshy tube1 or canal1 twenty-five feet in length4 ,the small intestine1 whose diameter is about one inch and a half1 is twenty feet long and very tortuous4 ,the large intestine is much wider than the former1 and five feet long 7,fig4 #bc74 ,the general structure of these organs resembles that of the stomach4 ,like it1 they are provided with a mucous membrane1 or inner lining1 whence flow their digestive juices2 and1 just outside of this1 a muscular coat1 which propels the food onward from one point to another4 ,sidenote3 #cb4 ,peritoneum8 ,the work of digestion8 #cb4 ,moreover1 both the intestines and stomach are enveloped in the folds of the same outer tunic or membrane1 called the peritoneum4 ,this is so smooth and so well lubricated1 that the intestines have the utmost freedom of motion4 ,in the small intestines1 the work of digestion is completed1 the large intestine receiving from them the indigestible residue of the food1 and in time expelling it from the body4 ,sidenote3 #cc4 ,the presence of food in the intestines8 ,bile8 #cc4 ,,intestinal ,,digestion4--,as soon as the food passes the pylorus and begins to accumulate in the upper #ie part of the intestines1 it excites the flow of a new digestive fluid1 which enters through a small tube1 or duct1 about three inches below the stomach4 ,it is formed by the union of two distinct fluids--the bile and the pancreatic juice4 ,the bile is secreted by the liver1 which is the largest gland of the body1 and is situated on the right side and upper part of the abdomen 7,fig4 #bb74 ,the bile is constantly formed1 but it flows most rapidly during digestion4 ,during the intervals of digestion it is stored in the gall-bladder1 a small membranous bag attached to the under side of the liver4 ,this fluid is of a greenish-yellow color1 having a peculiar smell1 and a very bitter taste4 ,sidenote3 #cd4 ,the pancreatic juice8 ,the joint action of these fluids8 #cd4 ,the pancreatic juice is the product of a gland called the pancreas1 situated behind the stomach4 ,this fluid is colorless1 viscid1 and without odor4 ,like the digestive juices previously described1 it owes its solvent power to its peculiar ferment principle1 called pancreatin4 ,by the joint action of these fluids1 the fatty parts of the food are prepared for absorption4 ,by previous steps of digestion the fats are merely separated from the other components of the food2 but here1 within the intestines1 they are reduced to a state of minute division1 or emulsion1 resembling the condition of butter in milk1 before it has been churned4 ,there results from this action a white and milky fluid1 termed the chyle1 which holds in solution the digestible portions of the food1 and is spread over the extensive absorbent surface of the small intestines4 ,sidenote3 #ce4 ,the mucous membrane8 ,experiments on inferior animals8 #ce4 ,the mucous membrane of the intestines1 also1 secretes or produces1 a digestive fluid by means of numerous follicles1 or minute glands2 this is called the intestinal juice4 ,from experiments on the inferior animals1 it has been ascertained that this fluid exerts a solvent influence over each of the three organic food principles1 and in this way may supplement and complete the action of the #if fluids previously mentioned1 viz43--of the saliva in converting starch into sugar1 of the gastric juice in digesting the albuminoids1 and of the pancreatic juice and bile in emulsifying the fats4 ,sidenote3 #cf1 #cg4 ,how much thus far has been done with the food8 ,the next process8 ,give the first way4 #cf4 ,,absorption4--,with the elaboration of the chyle1 the work of digestion is completed2 but1 in a certain sense1 the food is yet outside of the body2 that is1 the blood is not yet enriched by it1 and it is not in a position to nourish the tissues4 ,the process by which the liquefied food passes out of the alimentary canal into the blood is called absorption4 ,this is accomplished in two ways2 first1 by the blood-vessels4 ,we have seen how the inner membrane of the stomach is underlaid by a tracery of minute and numerous vessels1 and how some portions of the food are by them absorbed4 ,the supply of blood-vessels to the intestines is even greater2 particularly to the small intestines1 where the work of absorption is more actively carried on4 #cg4 ,the absorbing surface of the small intestines1 if considered as a plane surface1 amounts to not less than half a square yard4 ,besides1 the mucous membrane is formed in folds with an immense number of thread-like prolongations1 called villi1 which indefinitely multiply its absorbing capacity4 ,these minute processes1 the villi1 give the surface the appearance and smoothness of velvet2 and during digestion1 they dip into the canal1 and1 by means of their blood-vessels1 absorb its fluid contents1 just as the spongioles which terminate the rootlets of plants1 imbibe moisture from the surrounding soil4 ,sidenote3 #ch4 ,how is absorption effected in another way8 ,describe it4 ,name of the lacteals8 ,thoracic duct8 #ch4 ,secondly1 absorption is also effected by the lacteals1 a set of vessels peculiar to the small intestines4 ,these have their beginnings in the little villi just mentioned1 side by side with the blood-vessels4 ,these two sets of absorbents run in different courses1 but their destination is the same1 #ig which is the right side of the heart4 ,the lacteals receive their name from their milky-white appearance4 ,after a meal containing a portion of fat1 they are then distended with chyle1 which they are specially adapted to receive3 at other times they are hardly discernible4 ,the lacteals all unite to form one tube1 the thoracic duct1 which passes upward through the thorax1 or chest1 and empties into a large vein1 situated just beneath the left collar-bone4 ,illustration3 ,,fig4 #bd4--,,the ,,lacteals4 ,a1 ,small ,intestine4 ,b1 ,lacteals4 ,c1 ,thoracic ,duct4 ,d1 ,absorbents4 ,e1 ,blood-vessel4 ,sidenote3 #ci4 ,the absorbents8 ,lymph8 ,what further of the lymph8 #ci4 ,,the ,,absorbents4--,the lacteals belong to a class of vessels known as absorbents1 or lymphatics1 which ramify in nearly all parts of the body1 except the brain and spinal cord4 ,the fluid which circulates through the lymphatics of the limbs1 and all the organs not concerned in digestion1 is called lymph4 ,this fluid is clear and colorless1 like water1 and thus differs from the milky chyle which the lacteals carry after digestion3 it consists chiefly of the watery part of the blood1 which was not required by the tissues1 and is returned to the blood by the absorbents or lymphatics4 ,sidenote3 #dj4 ,what can you state as to the time required for digestion8 #dj4 ,,circumstances ,,affecting ,,digestion4--,what length of time is required for the digestion of food8 ,from observations made1 in the case of ,st4 ,martin1 the ,canadian #ih already referred to1 it has been ascertained that1 at the end of two hours after a meal1 the stomach is ordinarily empty4 ,how much time is needed to complete the digestion of food1 within the small intestines1 is not certain2 but1 from what we have learned respecting their functions1 it must be evident that it largely depends upon the amount of starch and fat which the food contains4 ,sidenote3 #da4 ,circumstances affecting duration of digestion8 ,fresh food8 #da4 ,in addition to the preparations which the food undergoes in cooking1 which we have already considered1 many circumstances affect the duration of digestion2 such as the quality1 quantity1 and temperature of the food2 the condition of the mind and body2 sleep1 exercise1 and habit4 ,fresh food1 except new bread and the flesh of animals recently slain1 is more rapidly digested than that which is stale2 and animal food more rapidly than that from the vegetable kingdom4 ,sidenote3 #db4 ,food in concentrated form8 ,a large quantity of food8 ,experiment on the dog8 ,ice-water8 ,variety of articles8 #db4 ,food should not be taken in too concentrated a form1 the action of the stomach being favored when it is somewhat bulky2 but a large quantity in the stomach often retards digestion4 ,if the white of one egg be given to a dog1 it will be digested in an hour1 but if the white of eight eggs be given it will not disappear in four hours4 ,a wineglassful of ice-water causes the temperature of the stomach to fall thirty degrees2 and it requires a half-hour before it will recover its natural warmth--about a hundred degrees--at which the operations of digestion are best conducted4 ,a variety of articles1 if not too large in amount1 is more easily disposed of than a meal made of a single article2 although a single indigestible article may interfere with the reduction of articles that are easily digested4 ,sidenote3 #dc4 ,strong emotion8 ,the tongue of the patient8 #dc4 ,strong emotion1 whether of excitement or depression1 checks digestion1 as do also a bad temper1 anxiety1 long fasting1 and bodily fatigue4 ,the majority of these #ii conditions make the mouth dry1 that is1 they restrain the flow of the saliva2 and without doubt they render the stomach dry also1 by preventing the flow of the gastric juice4 ,and1 as a general rule1 we may decide1 from a parched and coated tongue1 that the condition of the stomach is not very dissimilar1 and that it is unfit for the performance of digestive labor4 ,this is one of the points which the physician bears in mind when he examines the tongue of his patient4 ,sidenote3 #dd4 ,eating between meals8 ,severe exercise8 ,sleep after meals8 #dd4 ,the practice of eating at short intervals1 or between meals1 as it is called1 has its disadvantage1 as well as rapid eating and over-eating1 since it robs the stomach of its needed period of entire rest1 and thus overtasks its power4 ,with the exception of infants and the sick1 no persons require food more frequently than once in four hours4 ,severe exercise either directly before or directly after eating retards digestion2 a period of repose is most favorable to the proper action of the stomach4 ,the natural inclination to rest after a hearty meal may be indulged1 but should not be carried to the extent of sleeping2 since in that state the stomach1 as well as the brain and the muscles1 seeks release from labor4 #ajj ,,questions ,,for ,,topical ,,review4 ,,page #a4 ,what do you understand by nutrition8 #hj #b4 ,how is the process of nutrition carried on8 #hj #c4 ,what further can you state on the subject8 #hj1 #ha #d4 ,describe the general plan of digestion4 #ha #e4 ,how is the process of mastication carried on8 #hj1 #hb #f4 ,state what you can in relation to the formation of the teeth4 #hb1 #hf #g4 ,what1 in relation to their arrangement8 #hc1 #hd #h4 ,what1 in relation to the process of shedding8 #hb1 #hc1 #hd #i4 ,in relation to the different forms of teeth in different animals8 #he #aj4 ,what causes operate to injure or destroy the teeth8 #he1 #hf #aa4 ,what suggestions and directions are given for the preservation of the teeth8 #he1 #hf #ab4 ,what do you understand by insalivation8 #hj1 #hf #ac4 ,how is the process of insalivation carried on8 #hf1 #hg1 #hh #ad4 ,of what importance is the saliva to the process8 #hg1 #hh #ae4 ,of what importance are mastication and insalivation8 #hh1 #hi #af4 ,describe the consequences of rapid eating4 #hi1 #ij #ag4 ,what becomes of the food directly after it has undergone mastication and insalivation8 #ij #ah4 ,describe the location and formation of the stomach4 #ij1 #ia1 #ib #ai4 ,describe the process by which the gastric juice is formed4 #ia #bj4 ,what are the properties and uses of the gastric juice8 #ib #ba4 ,what are the movements of the stomach1 and what their uses8 #ib1 #ic #bb4 ,what further can you state on the subject8 #ic #bc4 ,what portions of the food are digested in the stomach8 #ic1 #id #bd4 ,what are the first changes of digestion8 #ic #be4 ,describe the location and formation of the stomach4 #id #bf4 ,what further can you state in relation to the stomach8 #id #bg4 ,describe the process of intestinal digestion4 #id1 #ie1 #if #bh4 ,what do you understand by absorption8 #hj1 #if #bi4 ,how is the process of absorption effected8 #if1 #ig #cj4 ,what are the lacteals and of what use are they8 #if1 #ig #ca4 ,what length of time is required for the digestion of food8 #ig1 #ih #cb4 ,what circumstances1 of food1 affect digestion8 #ih #cc4 ,what circumstances1 of emotion1 affect digestion8 #ih1 #ii #cd4 ,what suggestions and directions are given upon the subject of eating and drinking8 #ih1 #ii 99 99 99 99 99 ,illustration3 ,,circulation ,,of ,,the ,,blood4 ,heart1 ,lungs1 ,arteries ,veins4 #aja ,,chapter ,,vii4 ,,the ,,circulation4 ,the ,blood--,its ,plasma and ,corpuscles--,coagulation of the ,blood--,the ,uses of the ,blood--,transfusion--,change of ,color--,the ,organs of the ,circulation--,the ,heart1 ,arteries1 and ,veins--,the ,cavities and ,valves of the ,heart--,its ,vital ,energy--,passage of the ,blood through the ,heart--,the ,frequency and ,activity of its ,movements--,the ,pulse--,the ,sphygmograph--,the ,capillary ,blood-vessels--,the ,rate of the ,circulation--,assimilation--,injuries to the ,blood-vessels4 ,sidenote3 #a4 ,what is required by every living organism8 ,in plants8 ,insects8 ,reptiles8 ,man8 #a4 ,,the ,,blood4--,every living organism of the higher sort1 whether animal or vegetable1 requires for the maintenance of life and activity1 a circulatory fluid1 by which nutriment is distributed to all its parts4 ,in plants1 this fluid is the sap2 in insects1 it is a watery and colorless blood2 in reptiles and fishes1 it is red but cold blood2 while in the nobler animals and man1 it is the red and warm blood4 ,sidenote3 #b4 ,importance and abundance of blood8 ,dependence of life8 ,abel8 ,mosaic law8 ,in what part of the body is blood not found8 ,quantity of blood in the body8 #b4 ,the blood is the most important1 as it is the most abundant1 fluid of the body2 and upon its presence1 under certain definite conditions1 life depends4 ,on this account it is frequently1 and very properly1 termed the vital fluid4 ,the importance of the blood1 as essential to life1 was recognized in the earliest writings4 ,in the narration of the death of the murdered ,abel1 it is written1 the voice of his blood crieth from the ground4 ,in the ,mosaic law1 proclaimed over thirty centuries ago1 the ,israelites were forbidden to eat food that contained blood1 for the reason that the life of the flesh is in the blood4 ,with the exception of a few tissues1 such as the hair1 the nails1 and the cornea of the eye1 blood everywhere pervades the body1 as may be proven by puncturing any part with a #ajb needle4 ,the total quantity of blood in the body is estimated at about one-eighth of its weight1 or eighteen pounds4 ,sidenote3 #c4 ,color of blood8 ,its consistence8 ,odor8 #c4 ,the color of the blood1 in man and the higher animals1 as is well known1 is red2 but it varies from a bright scarlet to a dark purple1 according to the part whence it is taken4 ,blood is thicker than water1 as the adage truly states1 and has a glutinous quality4 ,it has a faint odor1 resembling that peculiar to the animal from which it is taken4 ,sidenote3 #d4 ,what is stated of the blood as viewed under the microscope8 #d4 ,when examined under the microscope1 the blood no longer appears a simple fluid1 and its color is no longer red4 ,it is then seen to be made up of two distinct parts3 first1 a clear1 colorless fluid1 called the plasma2 and secondly1 of a multitude of minute solid bodies1 or corpuscles1 that float in the watery plasma4 ,the plasma1 or nutritive liquid1 is composed of water richly charged with materials derived from the food1 viz41 albumen1 which gives it smoothness and swift motion2 fibrin2 certain fats2 traces of sugar2 and various salts4 ,illustration3 ,,fig #be4--,,the ,,blood ,,corpuscles4 ,sidenote3 #e4 ,state what you can of the little bodies called corpuscles4 #e4 ,,the ,,blood ,,corpuscles4--,in man1 these remarkable little bodies1 as the word corpuscles signifies1 are of a yellow color1 but by their vast numbers impart a red hue to the blood4 ,they are very small1 having a diameter of about #a_/cejj of an inch1 and being one-fourth of that fraction in thickness2 so that if #c1ejj of them were placed in line1 side by side1 they would only extend one inch2 or1 if #ajc piled one above another1 it would take at least #ad1jjj of them to stand an inch high4 ,although so small in size1 they are very regular in form4 ,as seen under the microscope1 they are not globular or spherical1 but flat1 circular1 and disc-like1 with central depressions on each side1 somewhat like a pearl button that has not been perforated4 ,in freshly-drawn blood they show a disposition to arrange themselves in little rolls like coins 7,fig4 #be74 ,illustration3 ,,fig4 #bf4 a1 ,oval ,corpuscles of a fowl4 b1 ,corpuscles of a frog4 c1 ,those of a shark4 ,the five small ones at the upper part of the figure1 represent the human corpuscles magnified #djj times4 ,sidenote3 #f4 ,the size and shape of corpuscles8 ,why is the fact important8 #f4 ,the size and shape of the blood corpuscles vary in different animals1 so that it is possible to discriminate between those of man and the lower animals 7,fig4 #bf74 ,this is a point of considerable practical importance4 ,for example1 it is sometimes desirable to decide in a court of justice the source1 whether from man or an inferior animal1 of blood stains upon the clothing of an accused person1 or upon some deadly weapon4 ,this may be done by a microscopical examination of a minute portion of the dried stain1 previously refreshed by means of gum-water4 ,certain celebrated cases are recorded in which the guilt of criminals has been established1 and they have been condemned and punished upon the evidence which science rendered on this single point1 the detecting of the human from other blood4 ,sidenote3 #g4 ,the character of the blood of dead animals8 ,means of detecting such blood8 #g4 ,the character of the blood of dead1 extinct1 and even fossil animals1 such as the mastodon1 has been ascertained by obtaining and examining traces of it which had been shut up1 perhaps for ages1 in the circulatory canals of bone4 ,a means of detecting blood in minute quantities is found #ajd in the spectroscope1 the same instrument by which the constitution of the heavenly bodies has been studied4 ,if a solution containing not more than one-thousandth part of a grain of the coloring matter of the corpuscle1 be examined1 this instrument will detect it4 ,sidenote3 #h4 ,white corpuscles8 ,total number of corpuscles in the body8 #h4 ,the corpuscles1 just described1 are known as the red blood corpuscles4 ,besides these1 and floating along in the same plasma1 are the white corpuscles4 ,these are fewer in number1 but larger and globular in form4 ,they are colorless1 and their motion is less rapid than that of the other variety4 ,the total number of both varieties of these little bodies in the blood is enormous4 ,it is calculated that in a cubic inch of that fluid there are eighty-three millions1 and at least five hundred times that number in the whole body4 ,sidenote3 #i4 ,the blood in its natural condition in the body8 ,describe the process by which the coagulation of blood takes place8 #i4 ,,coagulation4--,the blood1 in its natural condition in the body1 remains perfectly fluid2 but1 within a few minutes after its removal from its proper vessels1 whether by accident or design1 a change takes place4 ,it begins to coagulate1 or assume a semi-solid consistence4 ,if allowed to stand1 after several hours it separates into two distinct parts1 one of them being a dark red jelly1 the coagulum1 or clot1 which is heavy and sinks2 and the other1 a clear1 straw-colored liquid1 called serum1 which covers the clot4 ,this change is dependent upon the presence in the blood of fibrin1 which possesses the property of solidifying under certain circumstances2 one of these circumstances being when the blood is separated from living tissues4 ,the color of the clot is due to the entanglement of the corpuscles with the fibrin4 ,sidenote3 #aj4 ,if coagulation were impossible8 ,how is it in fact8 #aj4 ,in this law of the coagulation of the blood is our safeguard against death by hmorrhage1 or against undue loss of blood4 ,if coagulation were impossible1 the #aje slightest injury in drawing blood would prove fatal4 ,whereas now1 in vastly the larger proportion of cases1 bleeding ceases spontaneously1 because the blood1 as it coagulates1 stops the mouths of the injured blood-vessels4 ,in another class of cases1 where larger vessels are cut or torn1 it is simply necessary to close them by a temporary pressure2 for in a few minutes the clot will form and seal them up4 ,in still more serious cases1 where the blood-vessel is of large size1 the surgeon is obliged to tie a ligature about it1 and thus prevent the force of the blood-current from washing away the clots1 which1 forming within and around the vessel1 would close it effectually4 ,sidenote3 #aa4 ,what is worthy of remark8 ,coagulation of the blood of inferior animals8 ,of the blood of birds8 #aa4 ,it is worthy of remark that this peculiarity is early implanted in the blood1 even before birth1 and in advance of any existing necessity for it2 thus anticipating and guarding against danger4 ,but this is not all4 ,of most of the inferior animals1 which1 as compared with man1 are quite helpless1 the blood coagulates more rapidly1 and in the case of the birds1 almost instantly4 ,the relative composition of fluid and coagulated blood may be thus represented3 ,fluid ,blood4 ,coagulated ,blood4 ,plasma----------,serum---------,serum --------,fibrin-------- ,corpuscles------,corpuscles-------,clot 4 ,sidenote3 #ab4 ,the blood1 as a provider and purifier8 ,what uses does the blood subserve8 ,experiments8 ,transfusion8 #ab4 ,,the ,,uses ,,of ,,the ,,blood4--,the blood is the great provider and purifier of the body4 ,it both carries new materials to all the tissues1 and removes the worn out particles of matter4 ,this is effected by the plasma4 ,it both conveys oxygen and removes carbonic acid4 ,this is done through the corpuscles4 ,some singular experiments have #ajf been tried to illustrate the life-giving power of the blood4 ,an animal that has bled so freely as to be at the point of dying1 is promptly brought back to life by an operation called transfusion1 by which fresh blood from a living animal is injected into the blood-vessels of his body4 ,sidenote3 #ac4 ,the case of the deaf and feeble dog8 ,horse8 ,dead dog8 #ac4 ,it is related that a dog1 deaf and feeble from age1 had hearing and activity restored to him by the introduction into his veins of blood taken from a young dog2 and1 that a horse1 twenty-six years old1 having received the blood of four lambs acquired new vigor4 ,and further1 that a dog1 just dead from an acute disease1 was so far revived by transfusion1 as to be able to stand and make a few movements4 ,sidenote3 #ad4 ,transfusion1 as a fashionable remedy8 ,what further of transfusion8 #ad4 ,transfusion has been practised upon man4 ,at one time1 shortly after ,harvey's discovery of the ,circulation of the ,blood1 it became quite a fashionable remedy1 it being thought possible by it to cure all forms of disease1 and even to make the old young again4 ,but these claims were soon found extravagant1 and many unhappy accidents occurred in its practice2 so that being forbidden by government and interdicted by the ,pope1 it rapidly fell into disuse4 ,at the present time1 however1 it is sometimes resorted to in extreme cases1 when there has been a great and rapid loss of blood2 and there are upon record several instances where1 other means having failed1 life has been restored or prolonged by the operation of transfusion4 ,sidenote3 #ae4 ,the seat of the reviving power of the blood8 ,what further is related8 #ae4 ,this reviving power of the blood seems to reside in the corpuscles2 for transfusion1 when attempted to be performed with the serum alone1 has1 in every case1 proved fruitless4 ,now1 though so much depends upon the blood and its corpuscles1 it is a mistake to suppose that in them alone is the seat of life1 or that they are1 in an exclusive manner1 alive4 ,all the organs and parts of the body are mutually dependent one upon the other2 and the complete usefulness #ajg of the blood1 or of any other part1 flows out of the harmonious action of all the parts4 ,sidenote3 #af4 ,changes in the blood8 ,what further is stated8 #af4 ,,change ,,of ,,color4--,the blood undergoes a variety of changes in its journey through the system4 ,as it visits the different organs it both gives out and takes up materials4 ,in one place it is enriched1 in another it is impoverished4 ,by reason of these alterations in its composition1 the blood also changes its color4 ,in one part of the body it is bright red1 or arterial2 in another it is dark blue1 or venous4 ,in the former case it is pure and fit for the support of the tissues2 in the latter1 it is impure and charged with effete materials4 7,the details of the change from dark to bright will be given in the chapter on ,respiration47 ,sidenote3 #ag4 ,motion of the blood8 ,what is meant by the circulation of the blood8 ,how confined8 ,discovery made by ,harvey8 #ag4 ,,circulation4--,the blood is in constant motion during life4 ,from the heart1 as a centre1 a current is always setting toward the different organs2 and from these organs a current is constantly returning to the heart4 ,in this way a ceaseless circular movement is kept up1 which is called the ,circulation of the ,blood4 ,this stream of the vital fluid is confined to certain fixed channels1 the blood-vessels4 ,those branching from the heart are the arteries2 those converging to it are the veins4 ,the true course of the blood was unknown before the beginning of the seventeenth century4 ,in #afai it was discovered by the illustrious ,william ,harvey4 ,like many other great discoverers1 he suffered persecution and loss1 but unlike some of them1 he was fortunate enough to conquer and survive opposition4 ,he lived long enough to see his discovery universally accepted1 and himself honored as a benefactor of mankind4 #ajh ,illustration3 ,,fig4 #bg4--,,the ,,organs ,,of ,,circulation4 #aji ,illustration3 ,,fig4 #bh4--,,the ,,heart ,,and ,,large ,,vessels4 ,a1 ,right ,ventricle4 ,b1 ,left ,ventricle4 ,c1 ,right ,auricle4 ,d1 ,left ,auricle4 ,e1 ,aorta4 ,f1 ,pulmonary ,artery4 ,sidenote3 #ah4 ,office of the heart8 ,location of the heart8 ,its beat8 ,its shape8 ,protection to the heart8 ,what else is said in relation to the heart8 #ah4 ,,the ,,heart4--,the heart is the central engine of the circulation4 ,in this wonderful little organ1 hardly larger than a man's fist1 resides that sleepless force by which1 during the whole of life1 the current of the blood is kept in motion4 ,it is placed in the middle and front part of the chest1 inclining to the left side4 ,the heartbeat may be felt and heard between the fifth and sixth ribs1 near the breast-bone4 ,the shape of the heart is conical1 with the apex or point downward and in front4 ,the base1 which is upward1 is attached so as to hold it securely in its place1 while the apex is freely moveable4 ,in order that loss of power from friction may be obviated1 the heart is enclosed between two layers of serous membrane1 which forms a kind of sac4 ,this membrane is as smooth as satin1 and itself secretes a fluid in sufficient quantities to keep it at all times well lubricated4 ,the lining membrane of the heart1 likewise1 is extremely delicate and smooth4 #aaj ,illustration3 ,,fig4 #bi4--,,section ,,of ,,the ,,heart4 ,a1 ,right ,ventricle4 ,b1 ,left ,ventricle4 ,c1 ,right ,auricle4 ,d1 ,left ,auricle4 ,e1 ,f1 ,inlets to the ,ventricles4 ,g1 ,pulmonary ,artery4 ,h1 ,aorta4 ,sidenote3 #ai4 ,formation of the heart8 ,right and left heart8 #ai4 ,,the ,,cavities ,,of ,,the ,,heart4--,the heart is hollow1 and so partitioned as to contain four chambers or cavities2 two at the base1 known as the auricles1 from a fancied resemblance to the ear of a dog1 and two at the apex or point1 called ventricles4 ,an auricle and a ventricle on the same side1 communicate with each other1 but there is no opening from side to side4 ,it is customary to regard the heart as a double organ1 and to speak of its division into the right and left heart4 ,for while both halves act together in point of time1 each half sustains an entirely distinct portion of the labor of the circulation4 ,thus1 the right heart always carries the dark or venous blood1 and the left always circulates the bright or arterial blood4 ,sidenote3 #bj4 ,capacity of the chambers of the heart8 ,what wise provision is mentioned8 ,the auricles8 #bj4 ,if we examine the heart1 we at once notice that though its various chambers have about the same capacity1 the walls of the ventricles are thicker and stronger than those of the auricles4 ,this is a wise provision1 for it is by the powerful action of the former that the blood is forced to the most remote regions of the body4 ,the auricles1 on the contrary1 need much less power1 for they simply discharge their contents into the cavities of the heart near at hand and below them--into the ventricles4 #aaa ,sidenote3 #ba4 ,substance of the heart8 ,its fibres8 ,its movements8 ,the advantage of such movements8 ,action of the heart8 ,its period of repose8 #ba4 ,,action ,,of ,,the ,,heart4--,the substance of the heart is of a deep red color1 and its fibres resemble those of the voluntary muscles by which we move our bodies4 ,but the heart's movements are entirely involuntary4 ,the advantage of this is evident2 for if it depended upon us to will each movement1 our entire attention would be thus engaged1 and we would find no time for study1 pleasure1 or even sleep4 ,the action of the heart consists in alternate contractions and dilatations4 ,during contraction the walls come forcibly together1 and thus drive out the blood4 ,in dilatation1 they expand and receive a renewed supply4 ,these movements are called systole and diastole4 ,the latter may be called the heart's period of repose2 and although it lasts only during two-fifths of a heart-beat1 or about a third of a second1 yet during the day it amounts to more than nine hours of total rest4 ,sidenote3 #bb4 ,remarkable property of the tissue of the heart8 ,how shown8 ,how interesting8 ,in cold-blooded animals8 ,heart of a turtle8 ,of a frog8 ,alligator8 #bb4 ,a remarkable property of the tissue of the heart is its intense vitality4 ,for while it is more constantly active than any other organ of the body1 it is the last to part with its vital energy4 ,this is especially interesting in view of the fact that after life is apparently extinguished1 as from drowning1 or poisoning by chloroform1 there yet lingers a spark of vitality in the heart1 which1 by continued effort1 may be fanned into a flame so as to revivify the whole body4 ,in cold-blooded animals this irritability of the heart is especially remarkable4 ,the heart of a turtle will pulsate1 and the blood circulate for a week after its head has been cut off2 and the heart will throb regularly many hours after being cut out from the creature's chest4 ,the heart of a frog or serpent1 separated entirely from the body1 will contract at the end of ten or twelve hours3 that of an alligator has been known to beat twenty-eight hours after the death of the animal4 #aab ,sidenote3 #bc4 ,course of the blood through the heart8 ,course of heart-currents8 #bc4 ,,passage ,,of ,,the ,,blood ,,through ,,the ,,heart4--,let us now trace the course of the blood through the several cavities of the heart4 ,in the first place1 the venous blood1 rendered dark and impure by contact with the changing tissues of the body1 returns to the right heart by the veins4 ,it enters and fills the right auricle during its dilatation3 the auricle then contracts and fills the right ventricle4 ,almost instantly1 the ventricle contracts forcibly and hurries the blood along the great artery of the lungs1 to be purified in those organs4 ,secondly1 having completed the circuit of the lungs1 the pure and bright arterial blood enters the left auricle4 ,this now contracts and fills the left ventricle1 which cavity1 in its turn1 contracts and sends the blood forth on its journey again through the system4 ,this general direction from right to left is the uniform and undeviating course of heart-currents4 ,sidenote3 #bd4 ,openings of the ventricles8 ,how guarded8 ,how do the valves operate8 ,the consequence8 ,heart-sounds8 #bd4 ,the mechanism which enforces and regulates it1 is as simple as it is beautiful4 ,each ventricle has two openings1 an inlet and an outlet1 each of which is guarded by strong curtains1 or valves4 ,these valves open freely to admit the blood entering from the right1 but close inflexibly against its return4 ,thus1 when the auricle contracts1 the inlet valve opens2 but as soon as the ventricle begins to contract1 it closes promptly4 ,the contents are then1 so to speak1 cornered1 and have but one avenue of escape1 that through the outlet valve into the arteries beyond4 ,as soon as the ventricle begins to dilate again1 this valve shuts tightly and obstructs the passage4 ,the closing of these valves occasions the two heart-sounds1 which we hear at the front of the chest4 ,sidenote3 #be4 ,heart-beats8 ,the heart as a susceptible organ8 ,heat1 exercise1 etc48 ,posture8 #be4 ,,frequency ,,of ,,the ,,heart',s ,,action4--,the alternation of contraction and dilation constitutes the #aac heartbeats4 ,these follow each other not only with great regularity1 but with great rapidity4 ,the average number in an adult man is about seventy-two in a minute4 ,but the heart is a susceptible organ1 and many circumstances affect its rate of action4 ,heat1 exercise1 and food will increase its action1 as cold1 fasting1 and sleep will decrease it4 ,posture1 too1 has a curious influence2 for if while sitting1 the beats of the heart number seventy-one2 standing erect will increase them to eighty-one1 and lying down will lower them to sixty-six4 ,sidenote3 #bf4 ,mental emotions8 ,sudden excitement8 ,excessive joy8 ,the heart-beat rate8 ,bonaparte and ,wellington8 #bf4 ,the modifying influence of mental emotions is very powerful4 ,sudden excitement of feeling will cause the heart to palpitate1 or throb violently4 ,depressing emotions sometimes temporarily interrupt its movements1 and the person faints in consequence4 ,excessive joy1 grief1 or fear1 has occasionally suspended the heart's action entirely1 and thus caused death4 ,the rate of the heart-beat may be naturally above or below seventy-two4 ,thus it is stated that the pulse of the savage is always slower than that of the civilized man4 ,bonaparte and ,wellington were very much alike in their heart's pulsations1 which were less than fifty in the case of each4 ,sidenote3 #bg4 ,average number of heart-beats8 ,in one hour8 ,year8 ,lifetime8 #bg4 ,,activity ,,of ,,the ,,heart4--,the average number of heart-beats during a lifetime may be considered as at the rate of seventy-two per minute1 although this estimate is probably low2 for during several years of early life the rate is above one hundred a minute4 ,in one hour1 then1 the heart pulsates four thousand times2 in a day1 one hundred thousand times2 and in a year1 nearly thirty-eight million times4 ,if we compute the number during a lifetime1 thirty-nine years being the present average longevity of civilized mankind1 we obtain as the vast aggregate1 fourteen hundred millions of pulsations4 #aad ,sidenote3 #bh4 ,amount of blood expelled8 ,theories of the ancients8 #bh4 ,again1 if we estimate the amount of blood expelled by each contraction of the ventricles1 at four ounces1 then the weight of the blood moved during one minute will amount to eighteen pounds4 ,in a day it will be about twelve tons2 in a year1 four thousand tons2 and in the course of a lifetime1 over one hundred and fifty thousand tons4 ,these large figures indicate1 in some measure1 the immense labor necessary to carry on the interior and vital operations of our bodies4 ,in this connection1 we call to mind the fanciful theories of the ancients in reference to the uses of the heart4 ,they regarded it as the abode of the soul1 and the source of the nobler emotions--bravery1 generosity1 mercy1 and love4 ,the words courage and cordiality are derived from a ,latin word signifying heart4 ,many other words and phrases1 as hearty1 heart-felt1 to learn by heart1 and large-hearted1 show how tenaciously these exploded opinions have fastened themselves upon our language4 ,sidenote3 #bi4 ,the tendency at the present time8 ,why is this view inadequate8 #bi4 ,at the present time the tendency is to ascribe purely mechanical functions to the heart4 ,this view1 like the older one1 is inadequate2 for it expresses only a small part of our knowledge of this organ4 ,the heart is unlike a simple machine1 because its motive power is not applied from without1 but resides in its own substance4 ,moreover1 it repairs its own waste1 it lubricates its own action1 and it modifies its movements according to the varying needs of the system4 ,it is more than a mere force-pump1 just as the stomach is something more than a crucible1 and the eye something more than an optical instrument4 ,sidenote3 #cj4 ,what are the arteries8 ,their walls8 ,their membrane8 #cj4 ,,the ,,arteries4--,the tube-like canals which carry the blood away from the heart are the arteries4 ,their walls are made of tough1 fibrous materials1 so that they sustain the mighty impulse of the heart1 and are not ruptured4 ,in common with the heart1 the arteries have a #aae delicately smooth lining membrane4 ,they are also elastic1 and thus re-enforce the action of the heart3 they always remain open when cut across1 and after death are always found empty4 ,sidenote3 #ca4 ,early anatomists8 ,the service of the illustration8 #ca4 ,the early anatomists observed this phenomenon1 and supposing that the same condition existed during life1 came to the conclusion that these tubes were designed to act as air-vessels1 hence the name artery1 from a ,greek word which signifies containing air4 ,this circumstance affords us an illustration of the confused notions of the ancients in reference to the internal operations of the body4 ,cicero speaks of the arteries as conveying the breath to all parts of the body4 ,sidenote3 #cb4 ,the arterial system8 ,the branches and sub-branches of the arteries8 #cb4 ,the arterial system springs from the heart by a single trunk1 like a minute and hollow tree1 with numberless branches4 ,as these branches leave the heart they divide and subdivide1 continually growing smaller and smaller1 until they can no longer be traced with the naked eye4 ,if1 then1 we continue the examination by the aid of a microscope1 we see these small branches sending off still smaller ones1 until all the organs of the body are penetrated by arteries4 ,sidenote3 #cc4 ,successive undulations from the heart8 ,course of the arteries8 ,protection of the arteries8 ,general location of the arteries8 #cc4 ,,the ,,pulse4--,with each contraction of the left heart1 the impulse causes a wave-like motion to traverse the entire arterial system4 ,if the arteries were exposed to view1 we might see successive undulations speeding from the heart to the smallest of the branches1 in about one-sixth part of a second4 ,the general course of the arteries is as far as possible from the surface4 ,this arrangement is certainly wise1 as it renders them less liable to injury1 the wounding of an artery being especially dangerous4 ,it also protects the arteries from external and unequal pressure1 by which the force of the heart would be #aaf counteracted and wasted4 ,accordingly1 we generally find these vessels hugging close to the bones1 or hiding behind the muscles and within the cavities of the body4 ,sidenote3 #cd4 ,where do the arteries lie8 ,if we apply the finger8 ,pulse8 ,where felt8 #cd4 ,in a few situations1 however1 the arteries lie near the surface2 and if we apply the finger to any of these parts1 we will distinctly feel the movement described1 taking place in harmony with the heart-beat4 ,this is part of the wave-motion just mentioned1 and is known as the pulse4 ,all are more familiar with the pulse at the wrist1 in the radial artery2 but the pulse is not peculiar to that position1 for it may be felt in the carotid of the neck1 in the temporal at the temple1 and elsewhere1 especially near the joints4 ,illustration3 ,,fig4 #cj4--,,the ,,form ,,of ,,the ,,pulse4 ,sidenote3 #ce4 ,the pulse as an index8 ,of what does it inform the physician8 ,instrument for recording pulsation8 #ce4 ,since the heart-beat makes the pulse1 whatever affects the former affects the latter also4 ,accordingly1 the pulse is a good index of the state of the health1 so far as the health depends upon the action of the heart4 ,it informs the physician of the condition of the circulation in four particulars3 its rate1 regularity1 force1 and fullness2 and nearly every disease modifies in some respect the condition of the pulse4 ,a very ingenious instrument1 known as the sphygmograph1 or pulse-writer1 has recently been invented1 by the aid of which the pulse is made to write upon paper its own signature1 or rather to sketch its own profile4 ,this instrument shows with great accuracy the difference between the pulses of health and those of disease4 ,in ,fig4 #cj is traced the form of the pulse in health1 which should be read from left to right4 ,that part of the trace #aag which is nearly perpendicular coincides with the contraction of the ventricles2 while the wavy portion marks their dilatation4 ,sidenote3 #cf4 ,what are the veins8 ,how do they form8 ,what do they resemble8 #cf4 ,,the ,,veins4--,the vessels which convey the blood on its return to the heart are the veins4 ,they begin in the several organs of the body1 and at first are extremely small2 but uniting together as they advance1 they constantly increase in size1 reminding us of the way in which the fine rootlets of the plant join together to form the large roots1 or of the rills and rivulets that flow together to form the large streams and rivers4 ,in structure1 the veins resemble the arteries1 but their walls are comparatively inelastic4 ,they are more numerous1 and communicate with each other freely in their course1 by means of interlacing branches4 ,illustration3 ,,fig4 #ca4--,,the ,,valves ,,of ,,the ,,veins4 ,sidenote3 #cg4 ,valves in the veins8 ,what are they8 ,their position8 ,experiment with the cord8 #cg4 ,but the chief point of distinction is in the presence of the valves in the veins4 ,these are little folds of membrane1 disposed in such a way1 that they only open to receive blood flowing toward the heart1 and close against a current in the opposite direction4 ,their position in the veins on the back of the hand may be readily observed1 if we first obstruct the return of blood by a cord tied around the forearm or wrist4 ,in a few minutes the veins will appear swollen1 and upon them will be seen certain prominences1 about an inch apart4 ,these latter indicate the location of the valves1 or1 rather1 they show that the vessels in front of the valves are distended by the blood1 which cannot force a passage back through them4 ,sidenote3 #ch4 ,what will be proved by the experiment8 ,what inference is drawn8 #ch4 ,this simple experiment proves that the true direction of the venous blood is toward the heart4 ,that the color #aah of the blood is dark1 will be evident1 if we compare the hand thus bound by a cord with the hand not so bound4 ,it also proves that the veins lie superficially1 while the arteries are beneath the muscles1 well protected from pressure2 and that free communication exists from one vein to another4 ,if now we test the temperature of the constricted member by means of a thermometer1 we will find that it is colder than natural1 although the amount of blood is larger than usual4 ,from this fact we infer1 that whatever impedes the venous circulation tends to diminish vitality2 and hence1 articles of clothing or constrained postures1 that confine the body or limbs1 and hinder the circulation of the blood1 are to be avoided as injurious to the health4 ,sidenote3 #ci4 ,capillaries8 ,how regarded8 ,harvey8 #ci4 ,,the ,,capillaries4--,a third set of vessels completes the list of the organs of the circulation1 namely1 the capillary vessels1 so called 7from the ,latin word capillaris1 hair-like71 because of their extreme fineness4 ,they are1 however1 smaller than any hair1 having a diameter of about #a_/cjjj of an inch1 and can only be observed by the use of the microscope4 ,these vessels may be regarded as the connecting link between the last of the arteries and the first of the veins4 ,the existence of these vessels was unknown to ,harvey1 and was the one step wanting to complete his great work4 ,the capillaries were not discovered until #affa1 a short time after the invention of the microscope4 ,sidenote3 #dj4 ,the circulation of the blood in the web of a frog's foot8 ,describe it4 ,how general is the existence of the tissues8 #dj4 ,the circulation of the blood1 as seen under the microscope1 in the transparent web of a frog's foot1 is a spectacle of rare beauty1 possessing more than ordinary interest1 when we consider that something very similar is taking place in our own bodies1 on a most magnificent scale4 ,it is like opening a secret page in the history of our own frames4 ,we there see distinctly the three classes of vessels with their moving contents2 first1 the artery1 #aai with its torrent of blood rushing down from the heart1 secondly1 the vein1 with its slow1 steady stream flowing in the opposite direction2 and between them lies the network of capillaries1 so fine that the corpuscles can only pass through in single file4 ,the current has here an uncertain or swaying motion1 hurrying first in one direction1 then hesitating1 and then turning back in the opposite direction1 and sometimes the capillaries contract so as to be entirely empty4 ,certain of the tissues are destitute of capillaries2 such are cartilage1 hair1 and a few others on the exterior of the body4 ,in all other structures1 networks of these vessels are spread out in countless numbers3 so abundant is the supply1 that it is almost impossible to puncture any part with the point of a needle without lacerating tens1 or even hundreds of these vessels4 ,illustration3 ,,fig4 #cb4--,,web ,,of ,a ,,frog',s ,,foot1 slightly magnified4 ,illustration3 ,,fig4 #cc4--,,margin ,,of ,,frog',s ,,web magnified #cj diameters4 ,sidenote3 #da4 ,elasticity of the capillaries8 ,grain of sand in the eye8 ,blush8 ,other cases8 #da4 ,the capillaries are elastic1 and may so expand as to produce an effect visible to the naked eye4 ,if a grain of sand1 or some other foreign particle1 lodge in the eye1 it will become irritated1 and in a short time the white of the eye will be blood-shot4 ,this appearance is due to an #abj increase in the size of these vessels4 ,a blush is another example of this1 but the excitement comes through the nervous system1 and the cause is some transient emotion1 either of pleasure or pain4 ,another example is sometimes seen in purplish faces of men addicted to drinking brandy2 in them the condition is a congestion of the capillary circulation1 and is permanent1 the vessels having lost their power of elastic contraction4 ,sidenote3 #db4 ,show what time is required for a given portion of blood to travel once around the body4 #db4 ,,rapidity ,,of ,,the ,,circulation4--,that the blood moves with great rapidity is evident from the almost instant effects of certain poisons1 as prussic acid1 which act through the blood4 ,experiments upon the horse1 dog1 and other inferior animals1 have been made to measure its velocity4 ,if a substance1 which is capable of a distinct chemical reaction 7as potassium ferrocyanide1 or barium nitrate71 be introduced into a vein of a horse on one side1 and blood be taken from a distant vein on the other side1 its presence may be detected at the end of twenty or thirty-two seconds4 ,in man1 the blood moves with greater speed1 and the circuit is completed in twenty-four seconds4 ,sidenote3 #dc4 ,time required for all the blood to circulate completely around8 #dc4 ,what length of time is required for all the blood of the body to make a complete round of the circulation8 ,this question cannot be answered with absolute accuracy1 since the amount of the blood is subject to continual variations4 ,but1 if we assume this to be one-eighth of the weight of the body1 about eighteen pounds1 it will be sufficiently correct for our purpose4 ,now to complete the circuit1 this blood must pass once through the left ventricle1 the capacity of which is two ounces4 ,accordingly1 we find that1 under ordinary circumstances1 all the blood makes one complete rotation every two minutes2 passing successively through the heart1 the capillaries of the lungs1 the arteries1 the capillaries of the extremities1 and through the veins4 #aba ,sidenote3 #dd4 ,what is meant by assimilation8 ,what can you say of its use1 etc48 ,time8 #dd4 ,,assimilation4--,the crowning act of the circulation1 the furnishing of supplies to the different parts of the body1 is effected by means of the capillaries4 ,the organs have been wasted by use2 the blood has been enriched by the products of digestion4 ,here1 within the meshes of the capillary network1 the needy tissues and the needed nutriment are brought together4 ,by some mysterious chemistry1 each tissue selects and withdraws from the blood the materials it requires1 and converts them into a substance like itself4 ,this conversion of lifeless food into living tissue is called assimilation4 ,the process probably takes place at all times1 but the period especially favorable for it is during sleep4 ,then the circulation is slower1 and more regular1 and most of the functions are at rest4 ,the body is then like some trusty ship1 which after a long voyage is hauled up for repairs4 ,sidenote3 #de4 ,what is stated of the injuries to the blood-vessels8 #de4 ,,injuries ,,to ,,the ,,blood-,,vessels4--,it is important to be able to discriminate between an artery and a vein1 in the case of a wound1 and if we remember the physiology of the circulation we may readily do so4 ,for1 as we have already seen1 hmorrhage from an artery is much more dangerous than that from a vein4 ,the latter tends to cease spontaneously after a short time4 ,the arterial blood flows away from the heart with considerable force1 in jets2 its color being bright scarlet4 ,the venous blood flows toward the heart from that side of the wound furthest from the heart2 its stream being continuous and sluggish2 its color dark4 ,in an injury to an artery1 pressure should be made between the heart and the wound2 and in the case of a vein that persistently bleeds1 it should be made upon the vessel beyond its point of injury4 #abb ,,questions ,,for ,,topical ,,review4 ,,page #a4 ,in what organisms is the so-called circulatory fluid found8 #aja #b4 ,how is it designated in the different organisms8 #aja #c4 ,what can you state of the importance of blood to the body8 #aja1 #aje #d4 ,of its great abundance1 color1 and composition8 #aja1 #ajb1 #ajg #e4 ,describe the corpuscles of the human blood4 #ajb1 #ajc1 #ajd #f4 ,what is said of them in comparison with those of the lower animals8 #ajc #g4 ,of the importance of sometimes detecting human from other blood8 #ajc #h4 ,what means have we of detecting blood in spots or stains8 #ajc1 #ajd #i4 ,what is meant by coagulation of the blood8 #ajd #aj4 ,what wisdom is there in the law of the blood's coagulation8 #ajd1 #aje #aa4 ,how is this wisdom made manifest8 #aje #ab4 ,in what cases is the aid of the surgeon required8 #aje #ac4 ,what are the two great uses of the blood8 #aje #ad4 ,through what mediums is the blood provided with new material and relieved of the old material8 #aje #ae4 ,what do you understand by the operation called transfusion8 #ajf #af4 ,what cases of transfusion are reported of the lower animals8 #ajf #ag4 ,what can you state of transfusion as practised upon man8 #ajf #ah4 ,what further can you say on the subject8 #ajf1 #ajg #ai4 ,what changes take place in the color of the blood in its journey through the system8 #ajg #bj4 ,state all you can in relation to the circulation of the blood4 #ajg #ba4 ,all1 in relation to the size1 shape1 and location of the heart4 #ajg1 #aji #bb4 ,how is the loss of power in the heart movements obviated8 #aji #bc4 ,give a description of the formation of the heart4 #aji1 #aaj1 #aaa #bd4 ,what can you state of the ventricles and auricles of the heart8 #aaj #be4 ,describe the action of the heart4 #aaa #bf4 ,what special vitality does the tissue of the heart possess8 #aaa #bg4 ,state all you can on the subject4 #aaa #bh4 ,describe the course of the blood through the cavities of the heart4 #aab #bi4 ,describe the mechanism that regulates the heart-currents4 #aab #cj4 ,how do you account for the two heart-sounds at the front of the chest8 #aab #ca4 ,state what you can of the frequency of the heart's action4 #aab1 #aac #cb4 ,of the activity of the heart4 #aac1 #aad #cc4 ,what do you understand by the arteries8 #aad1 #aae #cd4 ,state what you can of the arteries and the arterial system4 #aad1 #aae #ce4 ,what do you understand by the pulse8 #aae1 #aaf #cf4 ,in what part of the body may the pulse be felt8 #aaf #cg4 ,what further can you state of the pulse8 #aaf1 #aag #ch4 ,what are the veins8 #aag #ci4 ,where do they exist1 and how are they formed8 #aag #dj4 ,describe the valves of the veins and their uses4 #aag #da4 ,now give a full description of the construction of the veins4 #aag #db4 ,what further can you state of the veins8 #aag1 #aah #dc4 ,what do you understand by the capillaries8 #aah1 #aai #dd4 ,what service do the capillaries perform8 #aah1 #aai1 #aba #de4 ,describe the circulation of the blood in the region of the heart4 #aah1 #aai #df4 ,what can you state of the rapidity of the blood's circulation8 #abj #dg4 ,of the process known as assimilation8 #aba #dh4 ,of injuries to the blood-vessels8 #aba 99 99 99 99 99 #abc ,,chapter ,,viii4 ,,respiration4 ,the ,objects of ,respiration--,the ,lungs--,the ,air-,passages--,the ,movements of ,respiration--,expiration and ,inspiration--,the ,frequency of ,respiration--,capacity of the ,lungs--,the ,air we breathe--,changes in the ,air from ,respiration--,changes in the ,blood--,interchange of ,gases in the ,lungs--,comparison between ,arterial and ,venous ,blood--,respiratory ,labor--,impurities of the ,air--,dust--,carbonic ,acid--,effects of ,impure ,air--,nature's ,provision for ,purifying the ,air--,ventilation--,animal ,heat--,spontaneous ,combustion4 ,sidenote3 #a4 ,difference between the two sets of capillaries8 ,change effected by respiration or breathing8 #a4 ,,the ,,object ,,of ,,respiration4--,in one set of capillaries1 or hair-like vessels1 the blood is impoverished for the support of the different members and organs of the body4 ,in another capillary system the blood is refreshed and again made fit to sustain life4 ,the former belongs to the greater or systemic circulation2 the latter to the lesser or pulmonary1 so called from pulmo1 the lungs1 in which organs it is situated4 ,the blood1 as sent from the right side of the heart to the lungs1 is venous1 dark1 impure1 and of a nature unfit to circulate again through the tissues4 ,but1 when the blood returns from the lungs to the left side of the heart1 it has become arterial1 bright1 pure1 and no longer hurtful to the tissues4 ,this marvellous purifying change is effected by means of the very familiar act of respiration1 or breathing4 ,sidenote3 #b4 ,what are the lungs8 ,how many lungs are there8 ,lung-substance8 ,its properties8 ,the pleura8 #b4 ,,the ,,lungs4--,the lungs are the special organs of respiration4 ,there are two of them1 one on each side of the chest1 which cavity they1 with the heart1 almost wholly occupy4 ,the lung-substance is soft1 elastic1 and sponge-like4 ,under pressure of the finger1 it crepitates1 or crackles1 and floats when thrown into water2 these properties being #abd due to the presence of air in the minute air-cells of the lungs4 ,to facilitate the movements necessary to these organs1 each of them is provided with a double covering of an exceedingly smooth and delicate membrane1 called the pleura4 ,one layer of the pleura is attached to the walls of the chest1 and the other to the lungs2 and they glide1 one upon the other1 with utmost freedom4 ,like the membrane which envelops the heart1 the pleura secretes its own lubricating fluid1 in quantities sufficient to keep it always moist4 ,illustration3 ,,fig4 #cd4--,,organs ,,of ,,the ,,chest4 ,a1 ,lungs4 ,b1 ,heart4 ,d1 ,pulmonary ,artery4 ,e1 ,trachea4 #abe ,illustration3 ,,fig4 #ce4--,,larynx1 ,,trachea1 ,,and ,,bronchial ,,tubes4 ,illustration3 ,,fig4 #cf4--;,,diagram ,,and ,,section ,,of ,,the ,,air-,,cells4 ,sidenote3 #c4 ,communication of the lungs with the external air8 ,bronchial tubes8 #c4 ,,the ,,air-,,passages4 --,the lungs communicate with the external air by means of certain air-tubes1 the longest of which1 the trachea1 or windpipe1 runs along the front of the neck 7,fig4 #cd1 ,e1 and #ce74 ,within the chest this tube divides into two branches1 one entering each lung2 these in turn give rise to numerous branches1 or bronchial tubes1 as they are called1 which gradually diminish in size until they are about one-twenty-fifth of an inch in diameter4 ,each of these terminates in a cluster of little pouches1 or air-cells1 having very thin walls1 and covered with a capillary network1 the most intricate in the body 7,fig4 #cf74 ,sidenote3 #d4 ,office of the bronchial tubes8 ,what further can you state of them8 #d4 ,these tubes are somewhat flexible1 sufficiently so to bend when the parts move in which they are situated2 but they are greatly strengthened by bands or rings of cartilage which keep the passages always open2 otherwise there would be a constantly-recurring tendency to collapse after every breath4 ,the lung-substance essentially consists of these bronchial tubes and terminal air-cells1 with the blood-vessels ramifying about them 7,fig4 #cg74 ,at the top of the trachea is the larynx1 a sort of #abf box of cartilage1 across which are stretched the vocal cords4 ,here the voice is produced chiefly by the passage of the respired air over these cords1 causing them to vibrate4 ,illustration3 ,,fig4 #cg4--,,section ,,of ,,the ,,lungs4 ,sidenote3 #e4 ,the epiglottis8 ,when it does not close in time1 what is the consequence8 #e4 ,over the opening of the larynx is found the epiglottis1 which fits like the lid of a box at the entrance to the lungs1 and closes during the act of swallowing1 so that food and drink shall pass backward to the oesophagus1 or gullet 7,fig4 #ch74 ,occasionally it does not close in time1 and some substance intrudes within the larynx1 when we at once discover1 by a choking sensation1 that something has gone the wrong way1 and1 by coughing1 we attempt to expel the unwelcome intruder4 ,the epiglottis is one of the many safeguards furnished by nature for our security and #abg comfort1 and is planned and put in place long before these organs are brought into actual use in breathing and in taking food4 ,illustration3 ,,fig4 #ch4--,,section ,,of ,,mouth ,,and ,,throat4 ,a1 ,the ,tongue4 ,b1 ,the ,uvula ,c1 ,vocal ,cord4 ,e1 ,epiglottis4 ,l1 ,larynx4 ,n1 ,trachea4 ,o1 ,oesophagus4 ,sidenote3 #f4 ,lining of the air-passages8 ,ciliated cells8 ,their uses8 ,the three diseases of the lungs8 #abh ,illustration3 ,,fig4 #ci4--;,,ciliated ,,cells4 #f4 ,the air-passages are lined through nearly their whole extent with mucous membrane1 which maintains these parts in a constantly moist condition4 ,this membrane has a peculiar kind of cells upon its outer surface4 ,if examined under a powerful microscope1 we may see1 even for a considerable time after their removal from the body1 that these cells have minute hair-like processes in motion1 which wave like a field of grain under the influence of a breeze 7,fig4 #ci74 ,this is a truly beautiful sight2 and since it is found that these little cilia1 as they are called1 always produce currents in one direction1 from within outward1 it is probable that they serve a useful purpose in catching and carrying away from the lungs dust and other small particles drawn in with the breath 7,fig4 #ci74 ,the three diseases which more commonly affect the lungs1 as the result of exposure1 are pneumonia1 or inflammation of the lungs1 implicating principally the air-cells2 bronchitis1 an inflammation of the large bronchial tubes2 and pleurisy1 an inflammation of the investing membrane of the lungs1 or pleura4 ,among the young1 an affection of the trachea takes place1 known as croup4 ,sidenote3 #g4 ,the act of breathing8 ,extension of the chest by breathing8 #g4 ,,the ,,movements ,,of ,,respiration4--,the act of breathing has two parts--7#a71 inspiration1 or drawing air into the lungs1 and 7#b71 expiration1 or expelling it from the lungs again4 ,in inspiration1 the chest extends in its length1 breadth1 and height1 or width4 ,we can prove that this is the case as regards the two latter1 by observing the effect of a deep breath4 ,the ribs are elevated by means of numerous muscles1 some of which occupy the entire spaces between those bones4 ,but the increase in length1 or vertically1 is not so apparent1 as it is caused by a muscle within the body called the diaphragm1 it being the thin partition which separates the chest from the abdomen1 rising like a dome within the chest4 7,fig4 #af74 #abi ,sidenote3 #h4 ,contraction of the diaphragm8 ,power of the diaphragm8 ,effects of extending the walls of the chest8 ,the habit of taking frequent and deep inspirations8 #h4 ,with every inspiration1 the diaphragm contracts1 and in so doing1 approaches more nearly a plane1 or horizontal1 surface1 and thus enlarges the capacity of the chest4 ,laughing1 sobbing1 hiccoughing1 and sneezing are caused by the spasmodic or sudden contraction of the diaphragm4 ,the special power of this muscle is important in securing endurance1 or long wind1 as it is commonly expressed2 which may be obtained mainly by practice4 ,it is possessed in a marked degree by the mountaineer1 the oarsman1 and the trained singer4 ,as the walls of the chest extend1 the lungs expand1 and the air rushes in to fill them4 ,this constitutes an inspiration4 ,the habit of taking frequent and deep inspirations1 in the erect position1 with the shoulders thrown back1 tends greatly to increase the capacity and power of the organs of respiration4 ,sidenote3 #i4 ,expiration8 ,the mechanism of expiration8 #i4 ,,expiration is a less powerful act than inspiration4 ,the diaphragm relaxes its contraction1 and ascends in the form of a dome2 the ribs descend and contract the chest2 while the lungs themselves1 being elastic1 assist to drive out the air4 ,the latter passes out through the same channels by which it entered4 ,at the end of each expiration there is a pause1 or period of repose1 lasting about as long as the period of action4 ,sidenote3 #aj4 ,frequency of respiration8 ,effect of hurried action of the heart8 #aj4 ,,frequency ,,of ,,respiration4--,it is usually estimated that we breathe once during every four beats of the heart1 or about eighteen times in a minute4 ,there is1 of course1 a close relation between the heart and lungs1 and whatever modifies the pulse1 in like manner affects the breathing4 ,when the action of the heart is hurried1 a larger amount of blood is sent to the lungs1 and1 as the consequence1 they must act more rapidly4 ,occasionally1 the heart beats so very forcibly that the lungs cannot keep pace with it1 and then we experience a peculiar sense of #acj distress from the want of air4 ,this takes place when we run until we are out of breath4 ,at the end of every fifth or sixth breath1 the inspiration is generally longer than usual1 the effect being to change more completely the air of the lungs4 ,sidenote3 #aa4 ,respiration controlled by the will8 ,advantage of the knowledge to us8 #aa4 ,although1 as a general rule1 the work of respiration goes on unconsciously and without exertion on our part1 it is nevertheless under the control of the will4 ,we can increase or diminish the frequency of its acts at pleasure1 and we can hold the breath1 or arrest it altogether for a short time4 ,from twenty to thirty seconds is ordinarily the longest period in which the breath can be held2 but if we first expel all the impure air from the lungs1 by taking several very deep inspirations1 the time may be extended to one and a half or even two minutes4 ,this should be remembered1 and acted upon1 before passing through a burning building1 or any place where the air is very foul4 ,the arrest of the respiration may be still further prolonged by training and habit2 thus it is said1 the pearl-fishers of ,india can remain three or four minutes under water without being compelled to breathe4 ,sidenote3 #ab4 ,capacity of the lungs8 ,time required to renovate the air in the lungs8 ,in tranquil respiration8 ,importance of the provision8 #ab4 ,,capacity ,,of ,,the ,,lungs4--,the lungs are not filled and emptied by each respiration4 ,for while their full capacity1 in the adult1 is three hundred and twenty cubic inches1 or more than a gallon1 the ordinary breathing air is only one-sixteenth part of that volume1 or twenty cubic inches1 being two-thirds of a pint4 ,accordingly1 a complete renovation1 or rotation1 of the air of the lungs does not take place more frequently than about once in a minute2 and by the gradual introduction of the external air1 its temperature is considerably elevated before it reaches the delicate pulmonary capillaries4 ,in tranquil respiration1 less than two-thirds of the breathing power is #aca called into exercise1 leaving a reserve capacity of about one hundred and twenty cubic inches1 equivalent to three and one half pints4 ,this provision is indispensable to the continuation of life2 otherwise1 a slight embarrassment of respiration1 by an ordinary cold1 for instance1 would suffice to cut off the necessary air1 and the spark of life would be speedily extinguished4 ,sidenote3 #ac4 ,the atmosphere8 ,how high or deep8 ,how essential to life8 ,marine life in perfectly pure water and air8 #ac4 ,,the ,,air ,,we ,,breathe4--,the earth is enveloped on all sides by an invisible fluid1 called the atmosphere4 ,it forms a vast and shoreless ocean of air1 forty-five miles deep1 encircling and pervading all objects on the earth's surface1 which is absolutely essential for the preservation of all vegetable and animal life1--in the sea1 as well as on the land and in the air4 ,at the bottom1 or in the lower strata of this aerial ocean1 we move and have our being4 ,perfectly pure water will not support marine life1 for a fish may be drowned in water from which the air has been exhausted1 just as certainly as a mouse1 or any other land animal1 will perish if put deeply into the water for a length of time4 ,the cause is the same in both cases3 the animal is deprived of the requisite amount of air4 ,it is also stated1 that if the water-supply of the plant be deprived of air1 its vital processes are at once checked4 ,sidenote3 #ad4 ,composition of the air8 ,properties of the two gases8 #ad4 ,the air is not a simple element1 as the ancients supposed1 but is formed by the mingling of two gases1 known to the chemist as oxygen and nitrogen1 in the proportion of one part of the former to four parts of the latter4 ,these gases are very unlike1 being almost opposite in their properties3 nitrogen is weak1 inert1 and cannot support life2 while oxygen is powerful1 and incessantly active2 and is the essential element which gives to the atmosphere its power to support life and combustion4 ,the discovery of this fact was made by the ,french chemist1 ,lavoisier1 in #aggh4 #acb ,sidenote3 #ae4 ,air once breathed8 ,an animal in it8 ,a candle8 ,analysis of expired air8 ,change in volume8 #ae4 ,,changes ,,in ,,the ,,air ,,from ,,respiration4--,air that has been once breathed is no longer fit for respiration4 ,an animal confined within it will sooner or later die2 so too1 a lighted candle placed in it will be at once extinguished4 ,if we collect a quantity of expired air and analyze it1 we shall find that its composition is not the same as that of the inspired air4 ,when the air entered the lungs it was rich in oxygen2 now it contains twenty-five per cent4 less of that gas4 ,its volume1 however1 remains nearly the same2 its loss being replaced by another and very different gas1 which the lungs exhaled1 called carbonic acid1 or1 as the chemist terms it1 carbon dioxide4 ,sidenote3 #af4 ,what else has the expired air gained8 ,when and where noticed8 #af4 ,the expired air has also gained moisture4 ,this is noticed when we breathe upon a mirror1 or the window-pane1 the surface being tarnished by the condensation of the watery vapor exhaled by the lungs4 ,in cold weather1 this causes the fine cloud which is seen issuing from the nostrils or mouth with each expiration1 and contributes in forming the feathery crystals of ice which decorate our window-panes on a winter's morning4 ,sidenote3 #ag4 ,nature of the watery vapor8 ,its effects upon animals8 #ag4 ,this watery vapor contains a variable quantity of animal matter1 the exact nature of which is unknown2 but when collected it speedily putrefies and becomes highly offensive4 ,from the effects1 upon small animals1 of confinement in their own exhalations1 having at the same time an abundant supply of fresh air1 it is believed that the organic matters thrown off by the lungs and skin are direct and active poisons2 and that to such emanations from the body1 more than to any other cause1 are due the depressing and even fatal results which follow the crowding of large numbers of persons into places of limited capacity4 #acc ,sidenote3 #ah4 ,give some of the instances furnished by history4 #ah4 ,history furnishes many painful instances of the ill effects of overcrowding4 ,in #agef1 of one hundred and forty-six ,englishmen imprisoned in the ,black ,hole of ,calcutta1 only twenty-three1 at the end of eight hours1 survived4 ,after the battle of ,austerlitz1 three hundred prisoners were crowded into a cavern1 where1 in a few hours1 two-thirds of their number died4 ,on board a steam-ship1 during a stormy night1 one hundred and fifty passengers were confined in a small cabin1 but when morning came1 only eighty remained alive4 ,sidenote3 #ai4 ,change in the blood from blue to red4 ,upon what does the change depend8 ,how shown8 #ai4 ,,changes ,,in ,,the ,,blood ,,from ,,respiration4--,the most striking change which the blood undergoes by its passage through the lungs1 is the change of color from a dark blue to bright red4 ,that this change is dependent upon respiration has been fully proved by experiment4 ,if the trachea1 or windpipe1 of a living animal be so compressed as to exclude the air from the lungs1 the blood in the arteries will gradually grow darker1 until its color is the same as that of the venous blood4 ,when the pressure is removed the blood speedily resumes its bright hue4 ,again1 if the animal be made to breathe an atmosphere containing more oxygen than atmospheric air1 the color changes from scarlet to vermilion1 and becomes even brighter than arterial blood4 ,this change of color is not of itself a very important matter1 but it indicates a most important change of composition4 ,sidenote3 #bj4 ,what does the air lose and gain by respiration8 ,what1 the blood8 ,air as food8 #bj4 ,the air1 as we have seen1 by respiration loses oxygen and gains carbonic acid3 the blood1 on the contrary1 gains oxygen and loses carbonic acid4 ,the oxygen is the food of the blood corpuscles2 while the articles we eat and drink belong more particularly to the plasma of the blood4 ,the air1 then1 it is plain1 is a sort of food1 and we should #acd undoubtedly so regard it1 if it were not for the fact that we require it constantly1 instead of taking it at stated intervals1 as is the case with our articles of diet4 ,again1 as the demand of the system for food is expressed by the sensation of hunger1 so the demand for air is marked by a painful sensation called suffocation4 ,sidenote3 #ba4 ,moist animal membranes8 ,how shown with the bladder8 #ba4 ,,interchange ,,of ,,gases ,,in ,,the ,,lungs4--,as the air and the blood are not in contact1 they being separated from each other by the walls of the air-cells and of the blood-vessels1 how can the two gases1 oxygen and carbonic acid1 exchange places8 ,moist animal membranes have a property which enables them to transmit gases through their substance1 although they are impervious to liquids4 ,this may be beautifully shown by suspending a bladder containing dark blood in a jar of oxygen4 ,at the end of a few hours the oxygen will have disappeared1 the blood will be brighter in color1 and carbonic acid will be found in the jar4 ,sidenote3 #bb4 ,gaseous diffusion8 ,if oxygen be not received8 ,if carbonic acid be retained8 #bb4 ,if this interchange takes place outside of the body1 how much more perfectly must it take place within1 where it is favored by many additional circumstances6 ,the walls of the vessels and the air-cells offer no obstacle to this process1 which is known as gaseous diffusion4 ,both parts of the process are alike of vital importance4 ,if oxygen be not received1 the organs cease to act2 and if carbonic acid be retained in the blood1 its action is that of a poison2 unconsciousness1 convulsions1 and death following4 ,sidenote3 #bc4 ,difference in the appearance and composition of the blood8 ,temperature of the blood8 ,the blood while passing through the lungs8 ,the consequence8 #bc4 ,,difference ,,between ,,arterial ,,and ,,venous ,,blood4--,the following table presents the essential points of difference in the appearance and composition of the blood1 before and after its passage through the lungs3-- #ace ,venous ,blood4 ,arterial ,blood4 ,color1 ,dark blue1 ,scarlet4 ,oxygen1 #h per cent41 #ah per cent4 ,carbonic ,acid1 #ae to #bj per cent41 #f per cent41 or less4 ,water1 ,more1 ,less4 ,the temperature of the blood varies considerably2 but the arterial stream is generally warmer than the venous4 ,the blood imparts heat to the air while passing through the lungs1 and consequently the contents of the right side of the heart has a higher temperature than the contents on the left side4 ,sidenote3 #bd4 ,what do we learn by means of the spectroscope8 ,carriers of oxygen8 ,blue blood in the system8 #bd4 ,by means of the spectroscope1 we learn that the change of color in the blood has its seat in the corpuscles2 and that1 according as they retain oxygen1 or release it1 they present the spectrum of arterial or venous blood4 ,there evidently exists1 on the part of these little bodies1 an affinity for this gas1 and hence they have been called carriers of oxygen4 ,it was long ago thought that blue blood was a trait peculiar to persons of princely and royal descent1 and boastful allusions to the sang azure of kings and nobles are quite often met with4 ,physiology1 however1 informs us that blue blood flows in the veins of the low as well as the high1 and that so far from its presence indicating a mark of purity1 it1 in reality1 represents the waste and decay of the system4 ,sidenote3 #be4 ,the amount of air that passes in and out of the lungs8 #be4 ,,amount ,,of ,,respiratory ,,labor4--,during ordinary calm respiration1 we breathe eighteen times in a minute2 and twenty cubic inches of air pass in and out of the lungs with every breath4 ,this is equivalent to the use of three hundred and sixty cubic inches1 or more than ten pints of air each minute4 ,from this we calculate that the quantity of air which hourly traverses the lungs is about thirteen cubic feet1 or seventy-eight gallons2 and daily1 not #acf less than three hundred cubic feet1 an amount nearly equal to the contents of sixty barrels4 ,sidenote3 #bf4 ,air absorbed in its transit through the lungs8 ,the loss8 ,carbonic acid exhaled8 ,effect of excitement or exertion8 ,what estimate8 #bf4 ,of this large volume of air five per cent4 is absorbed in its transit through the lungs4 ,the loss thus sustained is almost wholly of oxygen1 and amounts to fifteen cubic feet daily4 ,the quantity of carbonic acid exhaled by the lungs during the day is somewhat less1 being twelve cubic feet4 ,under the influence of excitement or exertion1 the breathing becomes more frequent and more profound2 and then the internal respiratory work increases proportionately1 and may even be double that of the above estimate4 ,it has been estimated that in drawing a full breath1 a man exerts a muscular force equal to raising two hundred pounds placed upon the chest4 ,sidenote3 #bg4 ,importance of the oxygen in the atmosphere8 ,injurious character of gases8 #bg4 ,,impurities ,,of ,,the ,,air4--,the oxygen in the atmosphere is of such prime importance1 and its proportion is so nicely adjusted to the wants of man1 that any gas or volatile substance which supplants it must be regarded as a hurtful impurity4 ,all gases1 however1 are not alike injurious4 ,some1 if inhaled1 are necessarily fatal2 arsenuretted hydrogen being one of these1 a single bubble of which destroyed the life of its discoverer1 ,gehlen4 ,others are not directly dangerous1 but by taking the place of oxygen1 and excluding it from the lungs1 they become so4 ,into this latter class we place carbonic acid4 ,sidenote3 #bh4 ,pungency of gases8 ,the inference8 ,our safeguard8 #bh4 ,most of the actively poisonous gases have a pungent or offensive odor2 and1 as may be inferred1 most repugnant odors indicate the presence of substances unfit for respiration4 ,accordingly1 as we cannot see or taste these impurities1 the sense of smell is our principal safeguard against them2 and we recognize the design which has planted this sense1 like a sentinel at the proper entrance of the #acg air-passages1 the nostrils1 to give us warning of approaching harm4 ,take1 as an example1 the ordinary illuminating gas of cities1 from which so many accidents happen4 ,how many more deaths would it cause if1 when a leak occurs1 we were not able to discover the escape of the gas by means of its disagreeable odor4 ,sidenote3 #bi4 ,the air of rooms in which fever-sick persons are confined8 #bi4 ,organic matters exist in increased measure in the expired breath of sick persons1 and impart to it1 at times1 a putrid odor4 ,this is especially true in diseases which1 like typhus and scarlet fever1 are referable to a blood poison4 ,in such cases the breath is one of the means by which nature seeks to expel the offending material from the system4 ,hence1 those who visit or administer to fever-sick persons should obey the oft-repeated direction1 not to take the breath of the sick4 ,at such times1 if ever1 fresh air is demanded1 not alone for the sick1 but as well for those who are in attendance4 ,sidenote3 #cj4 ,animalcula in the water8 ,dust in the air8 #cj4 ,,dust ,,in ,,the ,,air4--,attention has lately been directed to the dust1 or haze1 that marks the ray of sunshine across a shaded room4 ,just as1 many years ago1 it was discovered that myriads of animalcula infested much of the water we drank1 so now the microscope reveals the gay motes that dance along a sunbeam to be1 in part1 composed of multitudes of animal and vegetable forms of a very low grade1 the germs of fermentation and putrefaction1 and the probable sources of disease4 ,sidenote3 #ca4 ,the best air filter8 ,the remarks of ,prof4 ,tyndall8 #ca4 ,it is found that the best filter by which to separate this floating dust from the air is cotton wool1 although a handkerchief will imperfectly answer the same purpose4 ,in a lecture on this subject by ,prof4 ,tyndall1 he remarks that1 by breathing through a cotton wool respirator1 the noxious air of the sick room is restored to practical purity4 ,thus filtered1 attendants may breathe the air unharmed4 #ach ,in all probability1 the protection of the lungs will be the protection of the whole system4 ,for it is exceedingly probable that the germs which lodge in the air-passages are those which sow epidemic disease in the body4 ,if this be so1 then disease can certainly be warded off by filters of cotton wool4 ,by this means1 so far as the germs are concerned1 the air of the highest ,alps may be brought into the chamber of the invalid4 ,sidenote3 #cb4 ,carbonic acid in volcanic regions8 ,in ,java8 ,at ,lake ,avernus8 ,in mines8 #cb4 ,,carbonic ,,acid ,,in ,,the ,,air4--,we have already spoken of this gas as an exhalation from the lungs1 and a source of impurity2 but it exists naturally in the atmosphere in the proportion of one half part per thousand4 ,in volcanic regions it is poured forth in enormous quantities from fissures in the earth's surface4 ,being heavier than air1 it sometimes settles into caves and depressions in the surface4 ,it is stated that in the island of ,java1 there is a place called the ,valley of ,poison1 where the ground is covered with the bones of birds1 tigers1 and other wild animals1 which were suffocated by carbonic acid while passing4 ,the ,lake ,avernus1 the fabled entrance to the infernal regions1 was1 as its name implies1 bird-less1 because the birds1 while flying over it1 were poisoned by the gas and fell dead into its waters4 ,in mines1 carbonic acid forms the dreaded choke-damp1 while carburetted hydrogen is the fire-damp4 ,sidenote3 #cc4 ,in the open air8 ,amount of carbonic acid exhaled by a man8 ,a gas-burner8 ,a room fire8 ,from furnaces8 #cc4 ,in the open air1 men seldom suffer from carbonic acid1 for1 as we shall see presently1 nature provides for its rapid distribution1 and even turns it to profitable use4 ,but its ill effects are painfully evident in the abodes of men1 in which it is liable to collect as the waste product of respiration and of that combustion which is necessary for lighting and warming our homes4 ,a man exhales1 during repose1 not less than one-half cubic foot of carbonic acid per hour4 ,one gas-burner liberates five cubic feet in the #aci same time1 and spoils about as much air as ten men4 ,a fire burning in a grate or stove emits some gaseous impurity1 and at the same time abstracts from the air as much oxygen as twelve men would consume in the same period1 thus increasing the relative amount of carbonic acid in the air4 ,from furnaces1 as ordinarily constructed1 this gas1 with other products of combustion1 is constantly leaking and vitiating the air of tightly-closed apartments4 ,sidenote3 #cd4 ,effects of inhaling carbonic acid alone8 ,in small quantities8 #cd4 ,,effects ,,of ,,impure ,,air4--,carbonic acid1 in its pure form1 is irrespirable1 causing rapid death by suffocation4 ,air containing forty parts per thousand of this gas 7the composition of the expired breath7 extinguishes a lighted candle1 and is fatal to birds2 when containing one hundred parts1 it no longer yields oxygen to man and other warm-blooded animals2 and is of course at once fatal to them4 ,in smaller quantities1 this gas causes headache1 labored respiration1 palpitation1 unconsciousness1 and convulsions4 ,sidenote3 #ce4 ,effects of the air in crowded and badly ventilated rooms8 #ce4 ,in crowded and badly ventilated apartments1 where the atmosphere relatively contains from six to ten times the natural amount of carbonic acid1 the contaminated air causes dulness1 drowsiness1 and faintness2 the dark1 impure blood circulating through the brain1 oppressing that organ and causing it to act like a blunted tool4 ,this is a condition not uncommon in our schools1 churches1 court-rooms1 and the like1 the places of all others where it is desirable that the mind should be alert and free to act2 but1 unhappily1 an unseen physiological cause is at work1 dispensing weariness and stupor over juries1 audience1 and pupils4 ,sidenote3 #cf4 ,a cause of consumption8 ,how was the fact illustrated8 #cf4 ,another unmistakable result of living in and breathing foul air is found in certain diseases of the lungs1 especially consumption4 ,for many years the barracks of #adj the ,british army were constructed without any regard to ventilation2 and during those years the statistics showed that consumption was the cause of a very large proportion of deaths4 ,at last the government began to improve the condition of the buildings1 giving larger space and air-supply2 and as a consequence1 the mortality from consumption has diminished more than one-third4 ,sidenote3 #cg4 ,how1 in the case of the lower animals8 ,tendency of certain occupations8 #cg4 ,the lower animals confined in the impure atmosphere of menageries1 contract the same diseases as man4 ,those brought from a tropical climate1 and requiring artificial warmth1 generally die of consumption4 ,in the ,zoological gardens of ,paris1 this disease affected nearly all monkeys1 until care was taken to introduce fresh air by ventilation2 and then it almost wholly disappeared4 ,the tendency of certain occupations to shorten life is well known2 disease being occasioned by the fumes and dust which arise from the material employed1 in addition to the unhealthful condition of the workshop or factory where many hours are passed daily4 ,sidenote3 #ch4 ,give the fact as set forth in the table4 #ch4 ,the following table shows the comparative amount of carbonic acid in the air under different conditions and the effects sometimes produced3-- ,,proportion ,,of ,,carbonic ,,acid4 ,in #ajjj parts of ,air4 ,air of country4 4#d city4 4#e ,in hospital1 well ventilated4 4#f ,in school1 church1 etc41 fairly ventilated4 #a4b to #b4e ,in court-house1 factory1 etc41 without ventilation4 #d4 to #dj4 ,in bedroom1 before being aired4 #d4e ,in bedroom1 after being aired4 #a4e ,constantly breathed1 causing ill health4 #b4 ,occasionally breathed1 causing discomfort4 #c4 ,occasionally breathed1 causing distress4 #aj4 ,expired air4 #dj4 ,air no longer yielding oxygen #ajj4 #ada ,sidenote3 #ci4 ,what can you state of the diffusive power of gases8 ,the added influence of the winds8 #ci4 ,,nature',s ,,provision ,,for ,,purifying ,,the ,,air4--,we have seen that carbonic acid is heavier than air1 and is poisonous4 ,why1 then1 does it not sink upon and overwhelm mankind with a silent1 invisible wave of death8 ,among the gases there is a more potent force than gravity1 which forever precludes such a tragedy4 ,it is known as the diffusive power of gases4 ,it acts according to a definite law1 and with a resistless energy compelling these gases1 when in contact1 to mingle until they are thoroughly diffused4 ,the added influence of the winds is useful1 by insuring more rapid changes in the air2 air in motion being perfectly wholesome4 ,the rains also wash the air4 ,sidenote3 #dj4 ,how is the constant purity of the air secured8 ,explain the process8 #dj4 ,we have seen that the whole animal creation is constantly abstracting oxygen from the atmosphere1 and as constantly adding to it vast volumes of a gas injurious alike to all1 even in small quantities4 ,how1 then1 does the air retain1 unchanged1 its life-giving properties8 ,the constant purity of the air is secured by means of the vegetable creation4 ,carbonic acid is the food of the plants1 and oxygen is its waste product4 ,the leaves are its lungs1 and under the stimulus of sunlight a vegetable respiration is set in motion1 the effects of which are just the reverse of the function we have been considering4 ,thus nature purifies the air1 and at the same time builds up beautiful and useful forms of life from elements of decay4 ,sidenote3 #da4 ,what process occurs in the sea8 ,how is the fact illustrated8 #da4 ,in the sea1 as in the air1 the same circle of changes is observed4 ,marine animals consume oxygen and give off carbonic acid2 while marine plants consume carbonic acid and liberate oxygen4 ,taking advantage of this fact1 we may so arrange aquaria with fishes and sea-plants1 in their proper combinations1 so that each supplies the needs of the other1 and the water requires seldom to be renewed4 ,this #adb affords us1 on a small scale1 an illustration of the mutual dependence of the two great kingdoms of nature2 as well as of those compensating changes which are taking place on such a grand scale in the world about us4 ,sidenote3 #db4 ,character of the external air8 ,of the air in our dwellings8 ,what becomes imperative8 ,imperfect ventilation of our dwellings8 #db4 ,,ventilation4--,since the external atmosphere1 as provided by nature1 is always pure1 and since the air in our dwellings and other buildings is almost always impure1 it becomes imperative that there should be a free communication from the one to the other4 ,this we aim to accomplish by ventilation4 ,as our houses are ordinarily constructed1 the theory of ventilation1 to make the internal as pure as the external air1 is seldom carried out4 ,doors1 windows1 and flues1 the natural means of replenishing the air1 are too often closed1 almost hermetically1 against the precious element4 ,special means1 or special attention1 must therefore be used to secure even a fair supply of fresh air4 ,this is still more true of those places of public resort1 where many persons are crowded together4 ,sidenote3 #dc4 ,what hints are given for the ventilation of our dwellings8 #dc4 ,if there are two openings in a room1 one as a vent for foul air1 and the other an inlet for atmospheric air1 and if the openings be large1 in proportion to the number of air consumers1 the principal object will be attained4 ,thus1 a door and window1 each opening into the outer air1 will ordinarily ventilate a small apartment2 or a window alone will answer1 if it be open both above and below1 and the open space at each end be not less than one inch for each occupant of the room1 when the window is about a yard wide4 ,the direction of the current is generally from below upward1 since the foul1 heated air tends to rise2 but this is not essential4 ,its rate need not be rapid2 a draught1 or perceptible current1 is never necessary to good ventilation4 ,the temperature of the air admitted may be warm or cold4 ,it is thought by many that if the #adc air is cold1 it is pure2 but this is an error1 since cold air will receive and retain the same impurities as warm air4 ,sidenote3 #dd4 ,state what ,florence ,nightingale says about inhaling night air8 #dd4 ,shall we open our bedrooms to the night air8 ,florence ,nightingale says1 in effect1 that night air is the only air that we can then breathe4 ,the choice is between pure air without and impure air within4 ,most people prefer the latter1--an unaccountable choice4 ,an open window1 most nights in the year1 can hurt no one4 ,in great cities1 night air is the best and purest to be had in twenty-four hours4 ,i could better understand1 in towns1 shutting the windows during the day than during the night4 ,sidenote3 #de4 ,warmth of the bird as compared with that of the air8 ,of the fish and the water8 ,heat in animals and plants8 ,how illustrated with the thermometer8 #de4 ,,animal ,,heat4--,intimately connected with respiration is the production of animal heat1 or the power of maintaining the temperature of the body above that of the medium in which the creature moves2 thus1 the bird is warmer than the air1 and the fish than the water4 ,this elevation of temperature is a result of the various chemical changes which are constantly taking place in the system4 ,although common to all animals1 in a greater or less degree1 heat is not peculiar to them2 since plants also generate it1 especially at the time of sprouting and flowering4 ,if a thermometer be placed in a cluster of geranium flowers1 it will indicate a temperature several degrees above that of the surrounding air4 ,sidenote3 #df4 ,amount of heat in animals1 how apportioned8 ,as regards the birds8 ,frogs1 and other sluggish animals8 ,arrangement made by zoologists8 #df4 ,among animals great differences are noticed in this respect1 but the degree of heat produced is always proportional to the activity of respiration and the amount of oxygen consumed4 ,accordingly1 the birds1 whose habits are extremely active1 and whose breathing capacity is the greatest1 have uniformly the highest temperature4 ,sluggish animals1 on the contrary1 as frogs1 lizards1 and snakes1 have little need for oxygen1 and have incompletely #add developed lungs2 these animals are cold to the touch1 that is1 they have relatively a lower temperature than man1 and their positive temperature is but little above that of the external air4 ,accordingly1 zoologists have so arranged the animal kingdom that warm-blooded animals1 including man1 the birds1 and the quadrupeds1 are classified together2 while the cold-blooded animals1 such as the fish1 tortoise1 frog1 and all that have no vertebral column1 are classed by themselves4 ,sidenote3 #dg4 ,state what is said respecting the temperature of the human body4 #dg4 ,the temperature of the human body is about #ajj ,fahrenheit1 and remains about the same through winter and summer1 in the tropics as well as in the frozen regions of the north4 ,it may change temporarily within the range of about twelve degrees2 but any considerable1 or long-continued elevation or diminution of the bodily heat is certain to result disastrously4 ,sidenote3 #dh4 ,ability of man to adapt himself to different climates8 ,in what does the power to resist cold consist8 ,what is said about warm clothing8 #dh4 ,man is able to adapt himself to all extremes of climate2 and1 in fact1 by means of clothing1 shelter1 and food1 is able to create for himself an artificial climate where-ever he choses to reside4 ,the power to resist cold consists chiefly in preventing the heat which is generated by the vital processes of the body from being lost by radiation4 ,warm clothing1 such as we wear in winter1 has1 in reality1 the same temperature as that which is worn in summer2 but1 by reason of being thick and porous1 it is a bad conductor of heat1 and thus prevents the escape of that produced by the body4 ,if woollen fabrics were intrinsically warm1 no one would wrap a piece of flannel1 or blanket1 around a block of ice to prevent its melting in summer4 ,sidenote3 #di4 ,men in an atmosphere above the boiling-point8 ,in foundries and glass works8 #di4 ,the faculty of generating heat explains how it is that we are enabled to resist the effects of cold2 but how does the body withstand a temperature higher than its #ade own8 ,men have been known to remain several minutes in an atmosphere heated above the boiling-point of water1 and yet the temperature of their own bodies was not greatly elevated4 ,those who labor in foundries and glass-works are habitually subjected to very high degrees of temperature1 but they do not suffer in health more than those engaged in many other occupations4 ,sidenote3 #ej4 ,the regulation of the temperature of the body4 ,give the explanation4 #ej4 ,the regulation of the temperature of the body is effected by means of perspiration1 and by its evaporation4 ,so long as the skin acts freely and the air freely absorbs the moisture1 the heat of the body does not increase1 for whenever evaporation takes place1 it is attended by the abstraction of heat--that is1 the part becomes relatively colder4 ,this may be tested by moistening some part of the surface with cologne1 ether1 or other volatile liquid1 and then causing it to evaporate rapidly by fanning4 ,the principle that evaporation produces cold has been ingeniously and practically employed1 in the manufacture of ice1 by means of freezing machines4 ,sidenote3 #ea1 #eb4 ,state what is said of spontaneous combustion4 #ea4 ,,spontaneous ,,combustion4--,is it possible that the temperature of the living body can be so increased1 that its tissues will burn spontaneously8 ,from time to time1 cases have been reported in which1 by some mysterious means1 considerable portions of the human body have been consumed1 apparently by fire1 the victim being found dead1 or incapable of explaining the occurrence4 ,hence1 the theory has been current that1 under certain conditions1 the tissues of the body might become self-ignited2 and the fact that this so-called spontaneous combustion has ordinarily taken place in those who had been addicted to the use of alcoholic drinks1 has given a color of probability to the opinion4 ,it has been supposed that the flesh of these unfortunate persons becoming saturated with the inflammable properties of the alcohol thus taken into the #adf system1 took fire upon being exposed to a flame1 as of a lighted candle1 or1 indeed1 without any external cause4 ,but1 whether this be possible or not1 one thing is certain1 this strange kind of combustion has never been actually witnessed by any one competent to give a satisfactory account of it4 #eb4 ,the results that have been observed may be satisfactorily explained by the accidental ignition of the clothes1 or other articles near the body1 and by the supposition that the individual was at the time too much stupefied by intoxication1 to notice the source of danger1 and provide for his safety4 ,the highest temperature that has been observed in the body1 about #aab ,fahrenheit1 is too low to ignite the vapor of alcohol2 much less will it cause the burning of animal tissues4 ,it is undoubtedly true that when the tissues are filled with alcohol1 combustion will more easily take place than when the body is in a normal state2 but1 under any condition1 the combustion of the body requires a higher degree of heat than can be generated by the body itself1 or the mere proximity of a lighted candle1 or any cause of a similar character4 #adg ,,questions ,,for ,,topical ,,review4 ,,page #a4 ,what is the object of respiration8 #abc #b4 ,what are the special organs of respiration8 #abc #c4 ,in what organs does a change in the blood take place8 #abc #d4 ,what is the nature of the change8 #abc1 #acc #e4 ,where are the lungs situated1 and what is the character of the substance of which they are composed8 #abc1 #abe #f4 ,describe the facilities provided for the lung movements4 #abd #g4 ,describe the trachea1 or windpipe4 #abd1 #abe1 #abg1 #abh #h4 ,describe the bronchial tubes1 and their uses4 #abe1 #abf #i4 ,what can you state in relation to the epiglottis8 #abf1 #abg #aj4 ,what are the cilia and what use do they probably serve8 #abh #aa4 ,how may the lungs be affected by not being properly protected8 #abh #ab4 ,describe the movements necessary to the act of perfect respiration4 #abh1 #abi #ac4 ,what is the diaphragm1 and what is its office8 #abh1 #abi #ad4 ,how may the organs of respiration be so improved as to increase their capacity and power8 #abi1 #acg #ae4 ,what is stated in relation to the frequency of respiration8 #abi1 #acj #af4 ,to what extent may the act of respiration be subjected to our wills8 #acj #ag4 ,what may be said to be the capacity of the lungs8 #acj1 #aca #ah4 ,how long does it take every particle of air in the lungs to be expelled and new air to take its place8 #acj #ai4 ,what would be the consequences1 if the entire capacity of the lungs were constantly used8 #acj1 #aca #bj4 ,what would be the consequences to a fish put into water from which the air had been completely exhausted8 ,why8 #aca #ba4 ,what is the air1 and what are its parts8 #aca1 #acf1 #ach #bb4 ,what is the character of the air that has been just breathed8 #acb #bc4 ,why is it that such air is not fit for respiration8 #acb1 #aci #bd4 ,what are the effects1 as recorded in notable cases1 of confinement in places the air of which has been breathed over and over8 #acc #be4 ,what can you state of changes in the blood from respiration8 #acc #bf4 ,what of the air1 as an article of food8 #acc1 #acd #bg4 ,what1 on the subject of interchange of gases in the lungs8 #acd #bh4 ,explain the difference between arterial and venous blood4 #acd1 #ace #bi4 ,explain1 if you can1 the cause of the difference4 #ace #cj4 ,state what you can in relation to blue blood4 #ace #ca4 ,in relation to the amount of labor exerted in respiration4 #ace1 #acf #cb4 ,in relation to the deleterious properties of different gases4 #acf1 #acg #cc4 ,in relation to the dust that floats in the air4 #acg1 #ach #cd4 ,what are the properties of carbonic acid gas8 #acb1 #ach1 #ada #ce4 ,in what places is carbonic acid gas commonly found8 #acb1 #ach1 #aci #cf4 ,describe the effects of carbonic acid gas4 #acb1 #ach1 #aci1 #ada #cg4 ,what are the general effects of breathing any impure atmosphere8 #aci1 #adj #ch4 ,what are ,nature's provisions for purifying the air8 #ada1 #adb #ci4 ,what hints and directions are given on the subject of ventilation8 #adb1 #adc #dj4 ,how does the temperature of the body compare with the medium in which it lives8 #adc #da4 ,how is temperature of the body regulated and sustained8 #adc1 #add1 #ade #db4 ,state what you can on the subject of spontaneous combustion4 #ade1 #adf 99 99 99 99 99 #adh ,,chapter ,,ix4 ,,the ,,nervous ,,system4 ,animal and ,vegetative ,functions--,sensation1 ,motion1 and ,volition--,the ,structure of the ,nervous ,system--,the ,white and ,gray ,substances--,the ,brain--,its ,convolutions--,the ,cerebellum--,the ,spinal ,cord and its ,system of ,nerves--,the ,anterior and ,posterior ,roots--,the ,sympathetic ,system of ,nerves--,the ,properties of ,nervous ,tissue--,excitability of ,nervous ,tissues--,the ,functions of the ,spinal ,nerves and ,cord--,the ,direction of the ,fibres of the ,cord--,reflex ,activity1 and its ,uses--,the ,functions of the ,medulla ,oblongata and the ,cranial ,ganglia--,the ,reflex ,action of the ,brain4 ,sidenote3 #a4 ,what processes are known as the vegetative functions8 ,why so called8 ,what properties and functions does the plant possess8 ,their object8 #a4 ,,animal ,,functions4--,the vital processes which we have been considering1 in the three previous chapters1 of digestion1 circulation1 and respiration--belong to the class of functions known as vegetative functions4 ,that is1 they are common to vegetables as well as animals2 for the plant1 like the animal1 can originate nothing1 not even the smallest particle of matter2 and yet it grows1 blossoms1 and bears fruit1 by reason of obtaining and digesting the nutriment which the air and soil provide4 ,the plant has its circulatory fluid and channels1 by which the nutriment is distributed to all its parts4 ,it has1 also1 a curious apparatus in its foliage1 by which it abstracts from the air those gaseous elements so necessary to its support2 and thus it accomplishes vegetable respiration4 ,these vegetative functions have their beginning and end within the organism of the plant2 and their object is the preservation of the plant itself1 as well as of the entire species4 ,sidenote3 #b4 ,what second set of powers has the animal8 ,what functions are mentioned8 ,the advantage they give8 #b4 ,the animal1 in addition to these vegetative functions1 has another set of powers1 by the use of which he becomes conscious of a world external to himself1 and brings #adi himself into active relations with it4 ,by means of the vegetative processes1 his life and species are maintained2 while1 by means of certain animal functions1 he feels1 acts1 and thinks4 ,these functions1 among which are sensation1 motion1 and volition1 not only distinguish the animal from the plant1 but1 in proportion to their development1 elevate one creature above another2 and it is by virtue of his pre-eminent endowment1 in these respects1 that man holds his position at the head of the animal creation4 ,sidenote3 #c4 ,animals whose structure is simple8 ,as we approach man8 ,dependence of the animal functions of man8 #c4 ,among animals whose structure is very simple1 the hydra1 or fresh-water polyp1 being an example1 no special organs are empowered to perform separate functions2 but every part is endowed alike1 so that if the animal be cut into pieces1 each portion has all the properties of the entire original2 and1 if the circumstances be favorable1 each of the pieces will soon become a complete hydra4 ,as we approach man1 in the scale of beings1 we find that the organs multiply1 and the functions become more complete4 ,the function of motion1 the instruments of which--the muscles and bones--have been considered in former chapters1 and all the other animal functions of man1 depend upon the set of organs known as the nervous system4 ,sidenote3 #d4 ,the nervous tissues1 of what composed8 ,when examined by the aid of the microscope8 ,the white substance8 ,the gray substance8 #d4 ,,the ,,nervous ,,system4--,the intimate structure of this system differs from any tissue which we have before examined4 ,it is composed of a soft1 pulpy substance1 which1 early in life1 is almost fluid1 but which gradually hardens with the growth of the body4 ,when examined under the microscope1 it is found to be composed of two distinct elements3--7#a7 the white substance1 composing the larger proportion of the nervous organs of the body1 which is formed of delicate cylindrical filaments1 about #a_/fjjj of an inch in diameter1 termed the nerve-fibres2 and 7#b7 the gray substance1 composed of grayish-red1 or #aej ashen-colored cells1 of various sizes1 generally possessing one or more off-shoots1 which are continuous with the nerve-fibres just mentioned4 ,sidenote3 #e4 ,nervous centres and ganglia8 ,nerves8 ,what do they serve8 ,cerebro-spinal system8 #e4 ,the gray1 cellular substance constitutes the larger portion of those important masses1 which bear the name of nervous centres and ganglia 7from ganglion1 a knot71 and in which all the nerve-fibres unite4 ,these white nerve-fibres are found combined together in long and dense cords1 called nerves 7from neuron1 a cord71 which serve to connect the nervous centres with each other1 and to place them in communication with all the other parts of the body which have sensibility or power of motion4 ,that part of the nervous system which is concerned in the animal functions1 comprises the brain1 the spinal cord1 and the nerves which are derived therefrom2 these are1 together1 called the cerebro-spinal system 7,fig4 #dj72 while that other set of organs1 which presides over1 and regulates the vegetative functions1 is called the sympathetic system of nerves4 ,sidenote3 #f4 ,location of the brain8 ,its weight8 ,its shape8 ,of what it consists8 ,what organs at the base8 #f4 ,,the ,,brain4--,the brain is the great volume of nervous tissue that is lodged within the skull4 ,it is the largest and most complex of the nervous centres1 its weight1 in the adult1 being about fifty ounces1 or one-fortieth of that of the whole body4 ,the shape of the brain is oval1 or egg-shaped1 with one extremity larger than the other1 which is placed posteriorly in the skull1 to the concavity of which it very closely conforms4 ,the brain consists chiefly of two parts2 the cerebrum1 or brain proper1 and the cerebellum1 or little brain4 ,in addition to these1 there are several smaller organs at the base1 among which is the commencement or expansion of the spinal cord1 termed the medulla oblongata1 or oblong marrow4 #aea ,illustration3 ,,fig4 #dj4--,,the ,,cerebro-,,spinal ,,system4 #aeb ,sidenote3 #g4 ,the tissue of the brain8 ,what1 therefore1 is required8 ,blows on the head8 ,membranes of the brain8 ,blood sent to the brain8 #g4 ,the tissue of the brain is soft and easily altered in shape by pressure2 it therefore requires to be placed in a well-protected position1 such as is afforded by the skull1 or cranium1 which is strong without being cumbrous4 ,in the course of an ordinary lifetime1 this bony box sustains many blows1 with little inconvenience2 while1 if they fell directly upon the brain1 they would at once1 and completely1 disorganize that structure4 ,within the skull1 the brain is enveloped by certain membranes1 which at once protect it from friction1 and furnish it with a supply of nutrient vessels2 they are called the arachnoid1 or spider's web1 the dura mater and the pia mater1 or the tough and delicate coverings4 ,the supply of blood sent to the brain is very liberal1 amounting to one-fifth of all that the entire body possesses4 ,the brain of man is heavier than that of any other animal1 except the elephant and whale4 ,sidenote3 #h4 ,size of the brain proper8 ,how divided8 ,the exterior of the hemispheres8 ,the interior8 #h4 ,,the ,,cerebrum4--,the brain proper1 or cerebrum1 is the largest of the intracranial organs1 and occupies the entire upper and front portion of the skull4 ,it is almost completely bisected1 by a fissure1 or cleft1 running through it lengthwise1 into two equal parts called hemispheres4 ,the exterior of these hemispheres is gray in color1 consisting chiefly of nerve-cells1 arranged so as to form a layer of gray matter one-fifth of an inch in thickness1 and is abundantly supplied with blood-vessels4 ,the interior of the brain1 however1 is composed almost wholly of white substance1 or nerve-fibres4 ,sidenote3 #i4 ,the surface of the cerebrum1 how marked8 ,the gray matter of the surface8 ,extent of the entire brain surface8 ,source of nervous power8 ,what further8 #i4 ,the surface of the cerebrum is divided by a considerable number of tortuous and irregular furrows1 about an inch deep1 into convolutions1 as shown in ,fig4 #da4 ,into these furrows the gray matter of the surface is extended1 and1 in this manner1 its quantity is vastly increased4 ,the extent of the entire surface of the brain1 #aec with the convolutions unfolded1 is computed to be equal to four square feet2 and yet it is easily enclosed within the narrow limits of the skull4 ,when it is stated that the gray matter is the true source of nervous power1 it becomes evident that this arrangement has an important bearing on the mental capacity of the individual4 ,and it is noticed that in children1 before the mind is brought into vigorous use1 these markings or furrows on the surface are comparatively shallow and indistinct2 the same fact is true of the brain in the less civilized races of mankind and in the lower animals4 ,it is also noticeable1 that among animals1 those are the most capable of being educated which have the best development of the cerebrum4 ,illustration3 ,,fig4 #da4--,,upper ,,surface ,,of ,,the ,,cerebrum4 ,a1 ,longitudinal ,fissure4 ,b1 ,the ,hemispheres4 ,sidenote3 #aj4 ,location of the little brain8 ,how divided8 ,its surface and interior8 ,its subdivisions8 ,its size8 #aj4 ,,the ,,cerebellum4--,the little brain is placed beneath the posterior part of the cerebrum1 and1 like the latter1 is divided into hemispheres4 ,like it1 also1 the surface of the cerebellum is composed of gray matter1 and its interior is chiefly white matter4 ,it has1 however1 no convolutions1 but is subdivided by many crescentic1 parallel ridges1 which1 sending down gray matter deeply into the #aed white1 central portion1 gives the latter a somewhat branched appearance4 ,this peculiar appearance has been called the arbor vit1 or the tree of life1 from the fact that when a section of the organ is made1 it bears some resemblance to the trunk and branches of a tree 7,fig4 #db1 ,f74 ,in size1 this cerebellum1 or little brain1 is less than one-eighth of the cerebrum4 ,illustration3 ,,fig4 #db4--,,vertical ,,section ,,of ,,the ,,brain4 ,a1 ,left ,hemisphere of ,cerebrum4 ,b1 ,corpus ,callosum4 ,c1 ,optic ,thalamus4 ,d1 ,the ,pons ,varolii4 ,e1 ,upper extremity of the ,spinal ,cord4 ,f1 ,the ,arbor ,vit4 ,sidenote3 #aa4 ,medulla oblongata8 ,cranial nerves8 ,their shape and position8 #aa4 ,from the under surface of the cerebrum1 and from the front margin of the cerebellum1 fibres collect together to form the medulla oblongata 7,fig4 #dc1 ,,ma71 which1 on issuing from the skull1 enters the spinal column1 and then becomes known as the spinal cord4 ,from the base of the brain1 and from the sides of the medulla originate1 also1 the cranial nerves1 of which there are twelve pairs4 ,these nerves are round cords of glistening white appearance1 and1 #aee like the arteries1 generally lie remote from the surface of the body1 and are well protected from injury4 ,illustration3 ,,fig4 #dc4--,,the ,,base ,,of ,,the ,,brain4 ,sidenote3 #ab4 ,the spinal cord8 ,of what composed8 ,how divided8 ,each half8 #ab4 ,,the ,,spinal ,,cord4--,the spinal cord1 or marrow1 is a cylindrical mass of soft nervous tissue1 which occupies a chamber1 or tunnel1 fashioned for it in the spinal column 7,fig4 #dd74 ,it is composed of the same substances as the brain2 but the arrangement is exactly reversed1 the white matter encompassing or surrounding the gray matter instead of being encompassed by it4 ,the amount of the white substance is also greatly in excess of the other material4 ,a vertical fissure partly separates the cord into two lateral halves1 and each half is composed of two separate bundles of fibres1 which are named the anterior and posterior columns4 #aef ,illustration3 ,,fig4 #dd4 ,a1 ,cerebrum4 ,b1 ,cerebellum4 ,d1 ,d1 ,spinal ,cord4 ,sidenote3 #ac4 ,uses of these columns8 ,importance of this part of the nervous system8 ,how protected8 #ac4 ,these columns have entirely different uses1 and each of them unites with a different portion of the nerves which have their origin in the spinal cord4 ,the importance of this part of the nervous system is apparent from the extreme care taken to protect it from external injury4 ,for1 while a very slight disturbance of its structure suffices to disarm it of its power1 yet so staunch is its bony enclosure1 that only by very severe injuries is it put in peril4 ,the three membranes that cover the brain are continued downward so as to envelope and still further shield this delicate organism4 ,sidenote3 #ad4 ,the spinal nerves8 ,the posterior root8 ,the nerves1 how arranged8 ,their office8 #ad4 ,,the ,,spinal ,,nerves4--,the spinal nerves1 thirty-one pairs in number1 spring from each side of the cord by two roots1 an anterior and a posterior root1 which have the same functions as the columns bearing similar names4 ,the posterior root is distinguished by possessing a ganglion of gray matter1 and by a somewhat larger size4 ,the successive points of departure1 or the off-shooting of these nerves1 occur at short and nearly regular intervals along the course of the spinal cord4 ,soon after leaving these points1 #aeg the anterior and posterior roots unite to form the trunk of a nerve1 which is distributed1 by means of branches1 to the various organs of that part of the body which this nerve is designed to serve4 ,the spinal nerves supply chiefly the muscles of the trunk and limbs and the external surface of the body4 ,sidenote3 #ae4 ,the nerve tissue8 ,its character8 ,course of each nerve fibre8 #ae4 ,the tissue composing the nerves is entirely of the white variety1 or1 in other words1 the nerve-fibres2 the same as we have observed forming a part of the brain4 ,but the nerves1 instead of being soft and pulpy1 as in the case of the brain1 are dense in structure1 being hardened and strengthened by means of a fibrous tissue which surrounds each of these delicate fibres1 and binds them together in glistening1 silvery bundles4 ,delicate and minutely fine as are these nerve-fibres1 it is probable that each of them pursues an unbroken1 isolated course1 from its origin1 in the brain or elsewhere1 to that particular point which it is intended to serve4 ,for1 although their extremities are often only a hair's breadth distant from each other1 the impression which any one of them communicates is perfectly distinct1 and is referred to the exact point whence it came4 ,sidenote3 #af4 ,how may we illustrate the fact8 ,the fibre connecting the brain with a point in the foot8 #af4 ,this may be illustrated in a simple manner1 thus3 if two fingers be pressed closely together1 and the point of a pin be carried lightly across from one to the other1 the eyes may be closed1 and yet we can easily note the precise instant when the pin passes from one finger to the other4 ,if the nerve-fibres were less independent1 and if it were necessary that they should blend with and support each other1 all accuracy of perception would be lost1 and all information thus afforded would be pointless and confused4 ,these silvery threads must1 therefore1 be spun out with an infinite degree of nicety4 ,imagine1 for instance1 the fibre which #aeh connects the brain with some point on the foot1--its length cannot be less than one hundred thousand times greater than its diameter2 and yet it performs its work with as much precision as fibres that are comparatively much stronger and less exposed4 ,sidenote3 #ag4 ,the sympathetic system of nerves8 ,of what does it consist8 #ag4 ,,the ,,sympathetic ,,system4--,the sympathetic system of nerves remains to be described4 ,it consists of a double chain of ganglia1 situated on each side of the spinal column1 and extending through the cavities of the trunk1 and along the neck into the head4 ,these ganglia are made up for the most part of small collections of gray nerve-cells1 and are the nerve-centres of this system4 ,from these1 numerous small nerves are derived1 which connect the ganglia together1 send out branches to the cranial and spinal nerves1 and form networks in the vicinity of the stomach and other large organs4 ,a considerable portion of them also follows the distribution of the large and small blood-vessels1 in which the muscular tunic appears4 ,branches also ascend into the head1 and supply the muscles of the eye and ear1 and other organs of sense4 ,sidenote3 #ah4 ,association of the various regions of the body8 ,if one member suffers8 ,blushing8 #ah4 ,in this manner1 the various regions of the body are associated with each other by a nervous apparatus1 which is only indirectly connected with the brain and spinal cord2 and thus it is arranged that the most widely separated organs of the body are brought into close and active sympathy with each other1 so that1 if one member suffers1 all the other members suffer with it4 ,from this fact1 the name sympathetic system1 or the great sympathetic nerve1 has been given to the complicated apparatus we have briefly described4 ,blushing and pallor are caused by mental emotions1 as modesty and fear1 which produce opposite conditions of the capillaries of the face by means of these sympathetic nerves4 #aei ,sidenote3 #ai4 ,properties of nervous tissue8 ,office of the gray substance8 ,of the white8 ,the nervous centres8 ,white fibres8 #ai4 ,,the ,,properties ,,of ,,nervous ,,tissue4--,we have seen that in all parts of this system1 there are only two forms of nervous tissue2 namely1 the gray substance and the white substance1 so called from their difference of color as seen by the naked eye2 or the nerve-cell1 and the nerve-fibre1 so called from their microscopic appearance4 ,now these two tissues are not commonly mingled together1 but either form separate organs1 or distinct parts of the same organs4 ,this leads us to the conclusion that their respective uses are distinct4 ,and this proves to be the simple fact2 wherever we find the gray substance1 we must look upon it as performing an active part in the system1 that is1 it originates nervous impulses2 the white matter1 on the contrary1 is a passive agent1 and serves merely as a conductor of nervous influences4 ,accordingly1 the nervous centres1 composed so largely of the gray cells1 are the great centres of power1 and the white fibres are simply the instruments by which the former communicate with the near and distant regions of the body under their control4 ,sidenote3 #bj4 ,what comparison is made between the brain and the nation's capitol8 ,the vital property1 excitability8 ,what example is given8 #bj4 ,we may compare the brain1 then1 to the capital1 or seat of government1 while the various ganglia1 including the gray matter of the cord1 like so many subordinate official posts1 are invested with authority over the outlying provinces2 and the nerves1 with the white matter of the cord1 are the highways over which messages go and return between these provinces and the local or central governments4 ,but both forms of nervous tissue possess the same vital property1 called excitability2 by which term is meant1 that when a nerve-cell or fibre is stimulated by some external agent1 it is capable of receiving an impression and of being by it excited into activity4 ,a ray of light1 for example1 falling upon one extremity of a fibre in the eye1 excites it throughout its whole length2 and its #afj other extremity1 within the brain1 communicating with a nerve-cell1 the latter1 in its turn1 is excited1 and the sensation of sight is produced4 ,sidenote3 #ba4 ,change in the nervous tissues8 ,nerve force and electricity8 #ba4 ,what sort of change takes place in the nervous tissue when its excitability is aroused1 is not known2 certainly none is visible4 ,on this account1 it has been thought by some1 that the nerve-fibre acts after the manner of a telegraph wire2 that is1 it transmits its messages without undergoing any material change of form4 ,but1 though the comparison is a convenient one1 it is far from being strictly applicable2 and the notion that nerve-force is identical with electricity has been fully proved to be incorrect4 ,sidenote3 #bb4 ,functions of the nerves8 ,in the case of the nerve of a living animal8 ,of the human body8 #bb4 ,,the ,,functions ,,of ,,the ,,nerves4--,the nerves are the instruments of the two grand functions of the nervous system1 ,sensation and ,motion4 ,they are not the true centres of either function1 but they are the conductors of influences which occasion both4 ,if the nerve in a limb of a living animal be laid bare1 and irritated by pinching1 galvanizing1 or the like1 two results follow1 namely3 the animal experiences a sensation1 that of pain1 in the part to which the nerve is distributed1 and the limb is thrown into convulsive action4 ,when a nerve in a human body is cut by accident1 or destroyed by disease1 the part in which it ramifies loses both sensation and power of motion2 or1 in other words1 it is paralyzed4 ,we accordingly say that the nerves have a twofold use1 a sensory and motor function4 ,sidenote3 #bc4 ,if an exposed nerve be divided8 ,what is proved8 ,the course of the sensory set of fibres8 ,of the motor set8 ,to what are they likened8 #bc4 ,if a nerve that has been exposed be divided1 and the inner end1 or that still in connection with the nerve-centres1 be irritated1 sensation is produced1 but no movement takes place4 ,but if the outer end1 or that still connected with the limb1 be irritated1 then no pain is felt1 but #afa muscular contractions are produced4 ,thus we prove that there are two distinct sets of fibres in the nerves2 one of which1 the sensory fibres1 conduct toward the brain1 and another1 the motor fibres1 conduct to the muscles4 ,the former may be said to begin in the skin and other organs1 and end in the brain2 while the latter begin in the nervous centres and end in the muscles4 ,they are like a double line of telegraph wires1 one for inquiries1 the other for responses4 ,sidenote3 #bd4 ,the two roots of the spinal nerves8 ,what has been found8 ,difference of the two sorts of fibres8 ,result of their union8 #bd4 ,we have already spoken of the two roots of the spinal nerves1 called from their points of origin in the spinal cord1 the anterior and posterior roots4 ,these have been separately cut and irritated in the living animal1 and it has been found that the posterior root contains only sensory fibres1 and the anterior root has only motor fibres4 ,so that the nerves of a limb may be injured in such a way that it will retain power of motion and yet lose sensation2 or the reverse condition1 feeling without motion1 may exist4 ,between these two sorts of fibres1 no difference of structure can be found2 and where they have joined to form a nerve it is impossible to distinguish one sort from the other4 ,sidenote3 #be4 ,transient paralysis8 ,when such is the case with the leg8 ,what other fact is observed8 #be4 ,occasionally a nerve is so compressed as to be temporarily unable to perform its functions3 a transient paralysis then takes place4 ,this is the case when the leg or arm gets asleep1 as it is expressed4 ,when such is the condition with the leg1 and the person suddenly attempts to walk1 he is liable to fall1 inasmuch as the motor fibres cannot convey orders to the muscles of the limb4 ,another fact is observed3 there is no sensation in this nerve at the point of its compression2 but the whole limb is numb1 and tingling sensations are felt in the foot1 the point from which the sensory fibres arise4 ,sidenote3 #bf4 ,what does this illustrate8 ,sensation8 ,the feeling after a limb has been amputated8 ,striking of the funny bone8 #bf4 ,this illustrates the manner in which the brain #afb interprets all injuries of the trunk of a nerve4 ,sensation or pain is not felt at the point of injury1 but is referred to the outer extremities of the nerve1 where impressions are habitually received4 ,this is the reason why1 after a limb has been amputated by the surgeon1 the patient appears to suffer pain in the member that has been severed from the body2 while some form of irritation at the end of the nerve in the wound1 or stump1 is the real source of his distress4 ,again1 when the funny-bone--that is1 the ulnar nerve at the elbow1--is accidentally struck1 the tingling sensations thus produced are referred to the outer side of the hand and the little finger1 the parts to which that nerve is distributed4 ,sidenote3 #bg4 ,the spinal nerves1 and two from the brain8 ,of the remainder8 ,difference in the nerves8 ,how accounted for8 ,the rate of conduction along a nerve8 ,as compared with electricity8 #bg4 ,all the spinal nerves1 and two from the brain1 are concerned in both sensation and motion4 ,of the remainder of the cranial nerves1 some are exclusively motor1 others exclusively sensory2 and still others convey1 not ordinary sensations1 but special impressions1 such as sight1 hearing1 and smell1 which we have yet to consider4 ,however much the functions of the nerves seem to vary1 there is but little difference discoverable in the nerves themselves1 when examined under the microscope4 ,whatever difference exists must be accounted for in consequence of the nerves communicating with different portions of the gray matter of the brain4 ,the rate of motion of a message1 to or from the brain along a nerve1 has been measured by experiment upon the lower animals1 and estimated in the case of man at about two hundred feet per second4 ,as compared with that of electricity1 this is a very slow rate1 but1 in respect to the size of the human body1 it is practically instantaneous4 ,sidenote3 #bh4 ,functions of the anterior and posterior columns of the cord8 ,if the cord be divided8 #bh4 ,,the ,,functions ,,of ,,the ,,spinal ,,cord4--,as the #afc anterior and posterior roots of the spinal nerves have separate functions1 so the anterior and posterior columns of the cord are distinct in function4 ,the former are concerned in the production of motion1 the latter in sensation4 ,if the cord be divided1 as before in the case of the nerve1 it is found that the parts below the point of injury are deprived of sensation and of the power of voluntary motion on both sides of the body1 a form of paralysis which is called paraplegia4 ,sidenote3 #bi4 ,paraplegia8 ,result and danger to life8 ,when the injury occurs in the neck8 #bi4 ,this form of disease1 paraplegia1 is sometimes seen among men1 generally as the result of a fall1 or some other severe accident1 by which the bones of the spine are broken1 and the cord is crushed1 or pierced by fragments of bone4 ,the parts which are supplied by nerves from the cord above the point of injury are as sensitive and mobile as before4 ,the results are similar1 whether the division happens at a higher or lower portion of the spinal cord2 but the danger to life increases proportionally as the injury approaches the brain4 ,when it occurs in the neck1 the muscles of inspiration are paralyzed1 since they are supplied by nerves issuing from that region2 and as a result of this paralysis1 the lungs are unable to act1 and life is speedily brought to a close4 ,sidenote3 #cj4 ,experiment of cutting the spinal cord of an animal8 ,what inference is drawn8 #cj4 ,when the spinal cord of an animal has been cut1 in experiment1 it may be irritated in a manner similar to that alluded to when considering the nerves4 ,if1 then1 the upper cut surface be excited1 it is found that pain1 referable to the parts below the cut1 is produced2 but when the lower cut surface is irritated1 no feeling is manifested4 ,so we conclude that in respect to sensation1 the spinal cord is not its true centre1 but that it is merely a conductor1 and is therefore the great sensory nerve of the body4 ,when the lower surface of the cut is irritated1 the muscles of the #afd parts below the section are violently contracted4 ,hence1 we conclude that1 in respect to the movements ordered by the will1 the spinal cord is not their source2 but that it acts only as a conductor1 and is1 accordingly1 the great motor nerve of the body4 ,sidenote3 #ca4 ,what singular fact is noticed8 ,what does the result show8 #ca4 ,,direction ,,of ,,the ,,fibres ,,of ,,the ,,cord4--,if one lateral half of the spinal cord be cut1 or injured1 a very singular fact is observed4 ,all voluntary power over the muscles of the corresponding half of the body is lost1 but the sensibility of that side remains undiminished4 ,this result seems to show that the motor fibres of the cord pursue a direct course1 while its sensory fibres are bent from their course4 ,and this has been proved to be the fact2 for immediately after the posterior roots--the conductors of sensory impressions--join the posterior columns1 they enter the gray matter of the cord1 and passing over1 ascend to the brain on the opposite side4 ,accordingly1 the sensory fibres from the right and left sides interlace each other in the gray matter2 this arrangement has been termed the decussation1 or crossing of these fibres4 ,this condition serves to explain how a disease or injury of the cord may cause a paralysis of motion in one leg1 and a loss of sensation in the other4 ,sidenote3 #cb4 ,direction of the anterior or motor columns8 ,in the cord itself8 ,in the medulla oblongata8 ,the decussation8 #cb4 ,the direction of the anterior1 or motor columns of the cord1 is downward from the brain4 ,in the cord itself1 the course of the motor fibres is for the most part1 a direct one2 but in the medulla oblongata1 or upper extremity of the cord1 and therefore early in their career1 these fibres decussate1 or cross from side to side in a mass2 and not separately1 as in the case of the posterior fibres just mentioned4 ,this arrangement is termed the decussation of the anterior columns of the medulla4 ,sidenote3 #cc4 ,result of the double interlacing of fibres8 ,where is the seat of pain when the right hand is hurt8 ,the moving of the foot8 ,loss of sensation in one side of the body8 #cc4 ,from this double interlacing of fibres results a #afe crossed action between the original and terminal extremity of all nerve-fibres which pass through the medulla2 namely1 those of all the spinal nerves4 ,consequently1 if the right hand be hurt1 the left side of the brain feels the pain2 and if the left foot move1 it is the right hemisphere which dictates its movement4 ,for the same reason1 when a loss of sensation and power of motion affecting the right side of the body alone is observed1 the physiologist understands that the brain has been invaded by disease upon its left side4 ,this affection is termed hemiplegia1 or the half-stroke4 ,the full-stroke1 which often follows the rupture of a blood-vessel in the brain1 is commonly called paralysis4 ,sidenote3 #cd4 ,what other important use has the cord8 ,what is the activity denominated8 #cd4 ,,the ,,reflex ,,action ,,of ,,the ,,cord4--,we have already considered the cord as the great motor and sensory nerve of the body1 but it has another and extremely important use4 ,by virtue of the gray matter1 which occupies its central portion1 it plays the part of an independent nerve centre4 ,the spinal cord not only conducts some impressions to the brain1 but it also arrests others2 and1 as it is expressed1 reflects them into movements by its own power4 ,this mode of nervous activity is denominated the ,reflex ,action of the cord4 ,sidenote3 #ce4 ,example of the fowl8 ,centipede8 ,frog8 ,what do they prove8 #ce4 ,a familiar example of this power of the cord is found in the violent movements which agitate a fowl after its head has been cut off4 ,the cold-blooded animals also exhibit reflex movements in an astonishing degree4 ,a decapitated centipede will run rapidly forward1 and will seemingly strive to overturn1 or else climb over obstacles placed in its way4 ,a frog similarly mutilated will sustain its headless body upon its feet1 in the standing posture1 just as it might do if it were still alive4 ,if pushed over1 it will regain its feet2 and if the feet are irritated1 it will #aff jump forward4 ,there can be no doubt that1 in the lower animals1 movements may take place which are completely divorced from the will1 sensation1 and consciousness2 for in those animals1 as well as in man1 these faculties have their principal seat within the brain4 ,sidenote3 #cf4 ,what is necessary in most cases to awaken reflex movements8 ,in the case of the fowl8 ,convulsions which follow decapitation8 #cf4 ,an irritation is necessary1 in most instances1 to awaken reflex movements4 ,in the case of the decapitated fowl1 its muscles are excited to convulsive action by reason of its being thrown upon the hard ground and roughly handled4 ,let it be treated differently1 and the convulsions will not take place3 let it be laid gently upon soft cotton1 and the body will remain comparatively quiet4 ,it may comfort some people to know that the convulsions which follow decapitation are not attended with pain2 nor are they a necessary part of the act of death1 as some suppose4 ,sidenote3 #cg4 ,actions in the human body distinct from voluntary efforts8 #cg4 ,in the human body1 likewise1 actions are excited that are entirely distinct from the ordinary voluntary efforts4 ,it is not permissible1 desirable1 nor even necessary to decapitate a man that the body may be disconnected from his brain1 in order to test the effect of irritation upon the spinal cord2 although the bodies of beheaded criminals have been experimented upon1 and caused to move by powerful galvanic batteries4 ,the resort to such means of experiment is rendered unnecessary by the occurrence of certain deplorable cases of disease and injury1 which effectually sever all communication between the brain and a large part of the body4 ,sidenote3 #ch4 ,reflex action after injury of the cord8 ,why not due to the muscles8 #ch4 ,thus1 the cord may be so far injured1 as the result of accident1 as to terminate all sensation and voluntary motion in the lower half of the body1 the patient seemingly becoming lifeless and powerless from the waist downward4 ,and yet1 by tickling or pinching either foot1 the leg #afg of the same side may be made to jerk1 or even to kick with considerable force2 but1 unless the patient is observing his limbs1 he is wholly unconscious of these movements1 which are1 therefore1 performed independently of the brain4 ,and they are in nowise due to the muscles of the limb2 for1 if the cord itself becomes diseased below the point of injury1 the muscles cease to contract4 ,sidenote3 #ci4 ,what are the requisites for the production of this form of nervous action8 #ci4 ,for the production of this form of nervous action three things are requisite--7#a7 a nerve to conduct messages from the surface of the body1 one of that variety formerly described as sensory1 but which are now incapable of awakening sensation2 7#b7 a portion of uninjured spinal cord which shall reflect or convert impressions into impulses2 and 7#c7 a motor nerve to conduct impulses outward to the muscles4 ,the power of the cord to enforce reflex acts resides in the gray matter1 into which the reflex nerves enter and from which they depart1 by means of their posterior and anterior roots respectively4 ,sidenote3 #dj4 ,why do we not readily recognize the reflex activity of the cord in our own bodies8 ,how best studied in others8 ,example8 #dj4 ,,the ,,uses ,,of ,,the ,,reflex ,,action4--,the reflex activity of the cord is exhibited in the healthy body in many ways1 but since it is never accompanied with sensation1 we do not readily recognize it in our own bodies4 ,reflex movements are best studied in the cases of other persons1 when the conditions enable us to distinguish between acts that are consciously1 and those that are unconsciously performed4 ,for example1 if the foot of a person soundly asleep be tickled or pinched1 it will be quickly withdrawn from the irritation4 ,sidenote3 #da4 ,similar movements8 ,arm of a person8 ,melted wax or heated coin on the hand8 #da4 ,similar movements may be observed in cases where the consciousness and sensation are temporarily obliterated by disease1 or by means of narcotic poisons4 ,if the arm of a person who has been rendered insensible by #afh chloroform1 be raised1 and then allowed to fall1 it will be noticed that the limb does not drop instantly1 like a lifeless member1 but a certain amount of rigidity remains in its muscles1 which resists or breaks the force of its descent4 ,again1 when a substance like melted sealing-wax1 or a heated coin1 falls upon the hand1 the limb is snatched away at once1 even before the feeling of pain has been recognized by the brain4 ,when jolted in a rapidly moving car1 we involuntarily step forward or backward1 so as to preserve the centre of gravity of the body4 ,sidenote3 #db4 ,result of healthful reflex activity8 ,when may the reflex energy be deficient8 #db4 ,these and similar acts are executed by the same mechanism as that previously described in the case of paralysis from an injury of the spinal cord4 ,the muscles thus called into play1 are those which are ordinarily under the sway of the will1 but which in these cases act through this reflex action of the cord1 altogether independently of the will4 ,a healthful reflex activity produces an elasticity1 or tone1 of the voluntary muscular system1 which1 in a great measure1 explains the existence in the young and vigorous of a feeling of buoyancy and reserve power4 ,its possessor is restlessly active1 and it may appropriately be said of him1 he rejoiceth as a strong man to run a race4 ,but this reflex energy may be deficient4 ,this is true when the blood is poor and wanting in its solid ingredients1 or the circulation is feeble2 the muscles1 then1 are flabby and weak1 and the person himself is said to be nerveless1 or indisposed to exertion4 ,shivering from cold1 and trembling from fear1 may1 in part1 be referred to a temporary loss of tone1 resulting from a powerful impression upon the brain4 ,sidenote3 #dc4 ,excess of this activity in disease8 ,hydrophobia1 etc48 ,the difference in severity of the convulsions8 #dc4 ,an excess of this activity may also be observed in disease4 ,in this condition1 the excitability of the cord is unnaturally aroused1 and frequent and violent movements #afi of the limbs and body1 called convulsions1 are the result4 ,the convulsions of young children1 and the nervous agitation of chorea1 or ,st4 ,vitus's dance1 are reflex in character2 as are also the symptoms attending poisoning by strychnine1 and those terrible diseases1 tetanus1 or locked jaw1 and hydrophobia4 ,the severity of the convulsions is not the same in all cases of these disorders2 but1 in those last mentioned the most violent spasmodic movements are provoked by the slightest form of irritation--such as the sound of pouring water1 the sight of any glittering object1 the glancing of a mirror1 the contact of cool air1 or even the touch of the bedclothes4 ,sidenote3 #dd4 ,another variety of reflex motions8 ,what are they8 ,what is stated of the mind in connection with these movements8 #dd4 ,another variety of reflex motions takes place in certain involuntary muscles1 and over these the cord exercises supreme control4 ,they are principally those movements which aid the performance of digestion and nutrition1 the valve-action of the pylorus1 and other movements of the stomach and intestines4 ,in these movements the mind shares no part4 ,and it is well that this is so2 for since the mind is largely occupied with affairs external to the body1 it acts irregularly1 becomes fatigued1 and needs frequent rest4 ,the spinal cord1 on the contrary1 is well fitted for the form of work on which depends the growth and support of the body1 as it acts uniformly1 and with a machine-like regularity4 ,sidenote3 #de4 ,consciousness in these operations8 ,physical wants8 #de4 ,these operations are not accompanied by consciousness2 for1 as a general rule1 the attention is only called to them when they become disordered4 ,many a person does not know where his stomach is situated1 until he discovers its position by reason of a feeling of distress within it1 produced by giving that organ improper work to perform4 ,in this manner the higher and nobler faculties of the mind are liberated from the simply routine duties of the #agj body2 and we are thus left to direct the attention1 the reason1 and the will to the accomplishment of the great ends of our existence4 ,if it were otherwise1 we could only find time to attend to our ordinary physical wants4 ,sidenote3 #df4 ,how many objects may the reflex activity be said to have8 ,state the first4 ,the second4 ,the third4 #df4 ,the objects of the reflex activity of the cord are threefold4 ,in the first place1 it acts as the protector of man1 in his unconscious moments4 ,it is his unseen guardian1 always ready to act1 never growing weary1 and never requiring sleep4 ,nor does its faithful action wholly cease with the cessation of life in other parts4 ,in the second place1 it is the regulator of numerous involuntary motions that are necessary to the nutrition of the body4 ,here its actions are entirely independent of the brain1 and are performed in a secret and automatic manner4 ,and1 thirdly1 it acts as a substitute1 and regulates involuntary movements in the muscles usually under the influence of the will4 ,it thus takes the place of the higher faculties in performing habitual acts1 and permits them to extend their operations more and more beyond the body and its material wants4 ,sidenote3 #dg4 ,how does the medulla oblongata resemble the cord8 #dg4 ,,the ,,functions ,,of ,,the ,,medulla ,,oblongata4--,the prolongation of the spinal cord1 within the skull1 has been previously spoken of as the medulla oblongata4 ,it resembles the cord1 in being composed of both white and gray matter1 and in conducting sensory and motor influences4 ,it likewise gives rise to certain nerves1 which are here called cranial nerves 7from cranium1 the skull74 ,all except two of these important nerves spring from the medulla1 or the parts immediately adjoining it2 the exceptions are the two nerves taking part in the special senses of sight and smell1 which nerves have their origin at the base of the cerebrum4 ,sidenote3 #dh4 ,what final fact is observed in the crossing of the motor columns8 #dh4 ,the decussation1 or crossing of the motor columns1 has been previously described1 when treating of the #aga direction of the nerve-fibres of the cord2 and the singular fact has been alluded to1 that when one side of the brain is injured1 its effects are limited to the opposite side of the body4 ,one more fact remains to be observed in this connection1 namely1 this crossed action does not usually take place in the cranial nerves4 ,accordingly1 when apoplexy1 or the rupture of a blood-vessel1 occurs in the right hemisphere of the cerebrum1 the left side of the body is paralyzed1 but the right side of the face is affected2 this is because that part of the body is supplied by the cranial nerves4 ,sidenote3 #di4 ,the pneumogastric nerve8 ,the feelings aroused by it8 ,the vital knot8 #di4 ,a portion of the medulla presides over the important function of respiration1 and from it arises the pneumogastric nerve1 so called because its branches serve both the lungs and stomach4 ,the feelings of hunger1 thirst1 and the desire for air are aroused by means of this nerve4 ,the wounding of the gray matter of the medulla1 even of a small portion of it1 near the origin of the pneumogastric nerve1 at once stops the action of the lungs and causes death4 ,in consequence of the importance of this part1 it has been termed the vital knot4 ,we find1 also1 that its location within the skull is exceedingly well protected1 it being quite beyond the reach of any ordinary form of harm from without4 ,sidenote3 #ej4 ,the uses of the smaller gray masses at the base of the brain8 #ej4 ,,the ,,functions ,,of ,,the ,,cranial ,,ganglia4--,the uses of the smaller gray masses lying at the base of the brain are not well ascertained2 and1 on account of their position1 so remote from the surface1 it would1 at first1 seem well-nigh impossible to study them4 ,but1 from the results following diseases in these parts1 and from experiments upon inferior animals1 they are becoming gradually better understood2 and there is reason to believe that eventually the physiological office of each part will be clearly ascertained and defined4 ,it is believed1 however1 but not #agb absolutely proven1 that the anterior masses1 like the anterior roots of the spinal nerves and the anterior columns of the cord1 are concerned in the production of motion2 in fact1 that they are the central organs of that function4 ,the posterior gray masses are1 on the contrary1 supposed to be the seat of sensation4 ,sidenote3 #ea4 ,function of the cerebellum8 ,when it is diseased8 #ea4 ,,the ,,function ,,of ,,the ,,cerebellum4--,the function of the cerebellum1 or little brain1 is the direction of the movements of the voluntary muscles4 ,when this organ is the seat of disease or injury1 it is usually observed that the person is unable to execute orderly and regular acts1 but moves in a confused manner as if in a state of intoxication4 ,like the larger brain1 or cerebrum1 it appears to be devoid of feeling2 but it takes no part in the operations of the mind4 ,sidenote3 #eb4 ,where is the seat of the mind8 ,the subordination of the other organs8 ,the gray matter8 #eb4 ,,the ,,function ,,of ,,the ,,cerebrum4--,the cerebrum1 or brain proper1 is the seat of the mind2 or1 speaking more exactly1 it is the material instrument by which the mind acts2 and1 as it occupies the highest position in the body1 so it fulfils the loftiest uses4 ,all the other organs are subordinate to it3 the senses are its messengers1 which bring it information from the outer world1 and the organs of motion are its servants1 which execute its commands4 ,here1 as in the nervous apparatus of lower grade already considered1 the gray matter is the element of power2 and1 in proportion as this substance increases in extent1 and in proportion to the number of convolutions in the hemispheres1 do the mental faculties expand4 ,sidenote3 #ec4 ,what is stated of men in connection with the size of their brain8 ,with the brains of other animals8 #ec4 ,there have been a few1 but only a few1 men of distinguished ability whose brains have been comparatively small in size2 the rule being that great men possess large brains4 ,the relative weight of the brain of man1 as #agc compared with the weight of the body1 does not1 in all instances1 exceed that of the inferior animals2 the canary and other singing-birds have a greater relative amount of nervous matter than man2 but man surpasses all other creatures in the size of the hemispheres of the cerebrum1 and in the amount of gray substance which they contain4 ,sidenote3 #ed4 ,sensitiveness of the brain substance8 ,the removal of a portion of the brain8 ,state the remarkable case mentioned8 #ed4 ,it is a singular fact that this cerebral substance is insensitive1 and may be cut without causing pain4 ,the removal of a considerable quantity of the brain has taken place1 as the result of accident1 without causing death1 and without even affecting seriously the intellect4 ,a remarkable case of injury of the brain is recorded1 in which1 from the accidental explosion of gunpowder used in blasting a rock1 the tamping-iron was driven directly through the skull of a man4 ,this iron rod1 three feet and seven inches long1 an inch and a quarter in diameter1 and weighing more than thirteen pounds1 entered the head below the ear and passed out at the top of the skull1 carrying with it portions of the brain and fragments of bone4 ,the man sustained the loss of sight on one side1 but otherwise recovered his health and the use of his faculties4 ,moreover1 disease has occurred1 compromising a large portion of the brain1 without impairing the faculties of the mind1 when the disease was limited to one side only4 ,sidenote3 #ee4 ,thought1 emotion1 and will8 ,what power do they give us8 #ee4 ,impressions conveyed to the hemispheres from the external world arouse the mental operations called thought1 emotion1 and the will4 ,these are the godlike attributes which enable man to subjugate a world1 and afterward cause him to sigh for other worlds to conquer2 which enable him to acquaint himself with the properties of planets millions of miles distant from him1 and which give him that creative power by which he builds and peoples the new worlds of poetry and art4 #agd ,sidenote3 #ef4 ,are the brain and the mind identical8 #ef4 ,all these mental acts1 and many others1 are developed through the action of the brain2 not that the brain and the mind are the same1 or that the brain secretes memory1 imagination1 or the ideas of truth and justice1 as the stomach secretes the gastric juice4 ,but rather1 as the nerve of the eye1 stimulated by the subtile waves of light1 occasions the notion of color1 so the brain1 called into action by the mysterious influences of the immaterial soul1 gives rise to all the intellectual1 emotional1 and voluntary activities of mankind4 ,sidenote3 #eg4 ,what do we know of the cerebrum and its powers8 #eg4 ,the cerebrum1 according to our present knowledge of it1 must be regarded as a single organ1 which produces different results1 according as it is acted upon by the immaterial mind in different ways4 ,recent investigations1 however1 seem to prove that the faculty of language is dependent upon a small part of the left hemisphere of the cerebrum1 near the temple4 ,at least1 in almost every instance where this part is diseased1 the patient can no longer express himself in speech and writing4 ,sidenote3 #eh4 ,the reflex function of the organs within the skull8 ,the reflex power of the medulla8 ,respiration8 #eh4 ,,the ,,reflex ,,action ,,of ,,the ,,brain4--,the reflex function of the organs within the skull is very active and important4 ,like that of the cord1 it protects the body by involuntary movements1 it regulates the so-called vegetative acts1 and it takes the place of the will in controlling the voluntary muscles1 when the attention is turned in other directions4 ,the reflex power of the medulla governs the acts of respiration1 which are absolutely and continuously essential to life4 ,respiration is1 as we have seen1 partly under the influence of the will2 but this is due in part to the fact that respiration is indirectly concerned in one of the animal functions1 that of speech4 ,sidenote3 #ei4 ,what else does reflex action occasion8 ,winking8 ,other examples8 #ei4 ,reflex action also occasions coughing and sneezing1 #age whenever improper substances enter the air-passages4 ,winking is an act of the same sort1 and serves both to shield the eyes from too great glare of light1 and to preserve them by keeping the cornea moist4 ,looking at the sun or other strong light1 causes sneezing by reflex action4 ,laughing1 whether caused by tickling the feet or by some happy thought1 and also sobbing1 are reflex acts1 taking place by means of the respiratory muscles4 ,sidenote3 #fj4 ,muscles called into play by certain reflex movements8 ,the somnambulist8 #fj4 ,certain of the protective reflex movements call into play a large number of muscles1 as in the balancing of the body when walking along a narrow ledge1 or on a slippery pavement4 ,the dodging motion of the recruit1 when the first cannon ball passes over his head1 is reflex and involuntary4 ,the fact that these involuntary1 reflex acts are performed with great precision1 will explain why it is that accidents seldom befall the somnambulist1 or sleep-walker1 although he often ventures in most perilous places4 ,sidenote3 #fa4 ,what is said of walking and other acts in connection with the office performed by the medulla and spinal cord8 #fa4 ,walking1 sitting1 and other acts of daily life1 become automatic1 or reflex1 from habit3 the mind is seldom directed to them1 but delegates their control to the medulla and spinal cord4 ,thus a person in walking1 may traverse several miles while absorbed in thought1 or in argument with a companion1 and yet be conscious of scarcely one in a thousand of the acts that have been necessary to carry his body from one point to another4 ,by this admirable and beautiful provision1 the mind is released from the charge of the ordinary mechanical acts of life1 and may devote itself to the exercise of its nobler faculties4 ,and it is worthy of notice1 that the greater the use of these faculties1 the more work does the reflex function assume and perform2 and thus the employment of the one insures the improvement of the other4 #agf ,,questions ,,for ,,topical ,,review4 ,,page #a4 ,state fully what is meant by the term vegetable function4 #adh #b4 ,to what is man indebted for his position as the head of the animal creation8 #adh1 #adi #c4 ,what can you state on the subject of special organs for separate functions8 #adi #d4 ,describe1 as fully as you can1 the structure of the nervous system4 #adi1 #aej #e4 ,describe the brain1 its location1 size1 shape1 and structure4 #aej1 #aeb #f4 ,describe the brain proper1 or cerebrum4 #aeb1 #aec1 #agd #g4 ,what connection is noticed between the cerebrum and mental power8 #aec1 #agb1 #agd #h4 ,describe the little brain1 or cerebellum4 #aec1 #aed1 #agb #i4 ,describe the spinal cord4 #aed1 #aee1 #aef #aj4 ,what are the spinal nerves1 and how are they arranged8 #aef1 #aeg #aa4 ,what is the character and substance of their tissues8 #aeg #ab4 ,state how the nerve-fibres perform their office1 and give the illustration4 #aeg1 #aeh #ac4 ,describe the sympathetic system of nerves4 #aeh #ad4 ,state what is meant by the properties of nervous tissue1 and give the illustration4 #aei1 #afj #ae4 ,explain what is meant by the functions of the nerves1 and give the illustration4 #afj1 #afa1 #afb #af4 ,what is meant by a transient paralysis of a nerve8 ,give the illustration4 #afa1 #afb #ag4 ,what can you state of the rate of message-motion along a nerve8 #afb #ah4 ,what are the functions of the spinal cord8 #afb1 #afc1 #afd1 #afe #ai4 ,state what you can of the form of paralysis known as paraplegia4 #afc #bj4 ,what experiments1 with results1 upon the spinal cord are noted8 #afc1 #afd #ba4 ,explain how injury of the cord may produce paralysis of motion in one leg1 and at the same time a loss of sensation in the other4 #afd #bb4 ,explain how1 if the right hand be hurt1 the left side of the brain is made to feel the pain4 #afe #bc4 ,now1 explain as fully as you can the direction of the fibres of the cord4 #afd1 #afe #bd4 ,what is understood by the reflex action of the cord8 #afe #be4 ,what experiments are mentioned to prove this power of the cord8 #afe1 #aff #bf4 ,what are the uses of the reflex action of the cord8 #afg-agj #bg4 ,what illustrations are mentioned to show such uses8 #afg-agj #bh4 ,what is the medulla oblongata8 #aed1 #agj #bi4 ,what are the functions of the medulla oblongata8 #agj1 #aga #cj4 ,what can you state of the functions of the cranial ganglia8 #aga1 #agb #ca4 ,what are the functions of the cerebellum8 #agb #cb4 ,what is the function of the cerebrum8 #agb1 #agd #cc4 ,in what way does the size of the brain generally indicate the character of the man8 #agb1 #agc #cd4 ,what facts show that the gray substance of the brain is insensitive8 #agc #ce4 ,upon what does the faculty of language seem to depend8 #agd #cf4 ,what has been observed in support of this statement8 #agd #cg4 ,of what importance is the reflex action of the brain8 #agd1 #age #ch4 ,in what ways is this importance made manifest8 #agd1 #age 99 99 99 99 99 #agg ,,chapter ,x4 ,,the ,,special ,,senses4 ,the ,production of ,sensations--,variety of ,sensations--,general ,sensibility--,pain and its ,function--,special ,sensation1 ,touch1 ,taste1 ,smell1 ,sight1 and ,hearing--,the ,hand1 the ,organ of ,touch--,the ,sense of ,touch--,delicacy of ,touch--,sensation of ,temperature and ,weight--,the ,tongue the ,organ of ,taste--,the ,nerves of ,taste--,the ,sense of ,taste and its ,relations with the other ,senses--,the ,influence of ,education on the ,taste--,the ,nasal ,cavities1 or the organs of ,smell--,the ,olfactory ,nerve--,the ,uses of the ,sense of ,smell--,the ,sense of ,sight--,light--,the ,optic ,nerve--,the ,eyeball and its ,coverings--,the ,function of the ,iris--,the ,sclerotic1 ,choroid1 and ,retina--,the ,tears and their ,function--,the ,movements of the ,eyeball--,the ,function of ,accommodation--,the ,sense of ,hearing and ,sound--,the ,ear1 or the organ of ,hearing--,the ,external1 ,middle1 and ,internal ,ear4 ,sidenote3 #a4 ,true centre of sensation8 ,place of the mind's impressions8 ,what is it convenient to say8 ,what further is stated8 #a4 ,,production ,,of ,,sensations4--,we have already seen that the true centre of sensation is some organ within the skull1 probably among the gray masses at the base of the brain2 but the mind never perceives impressions at that point2 but1 on the contrary1 always refers them to the external organs of sensation4 ,hence1 it is convenient to say1 that those outer parts possess the property of sensibility4 ,for instance1 we say that we hear with the ear1 taste with the tongue1 and feel with the fingers4 ,that this is not the exact truth is proven by the fact1 that whenever the nerve connecting one of these organs with the brain is severed1 it at once loses its capacity for sensation4 ,sidenote3 #b4 ,consciousness8 ,during sleep8 ,in profound insensibility8 #b4 ,consciousness1 another faculty of the brain1 is necessary to complete a sensation4 ,during sleep1 and in other unconscious states1 the usual impressions are presented to #agh the ear1 the nose1 and the skin1 but they fail to excite sensations1 because the nerve-centres are inactive4 ,in profound insensibility1 from chloroform or ether1 a limb may be removed without occasioning the least feeling4 ,sidenote3 #c4 ,sensibility in animals8 ,in the earth-worm8 ,in man8 #c4 ,,variety ,,of ,,sensations4--,all animals have some degree of sensibility4 ,it is of course feeble and indistinct in the lower forms of life1 but increases in power and variety as we ascend the scale4 ,in the earth-worm1 the nervous system is very simple1 the sensibility being moderate and alike in all parts3 hence1 if its body be cut into two pieces1 each piece will have the same degree of feeling as before4 ,as we approach man1 however1 the sensations multiply and become more acute2 the organs are more complex1 and special parts are endowed with special gifts4 ,these special organs cannot be separated from the rest of the body without the loss of the functions they are designed to exercise4 ,sidenote3 #d4 ,the lowest form of sensation8 ,the highest8 ,sensations1 how modified8 ,what further can you state as to habitual impressions8 #d4 ,the lowest form of sensation1 that of simple contact1 is possessed by the lowest of the animal creation4 ,the highest forms are those by which we are enabled to know the properties of external objects1 such as shape1 size1 sound1 and color4 ,a variety of means of communicating with the outer world is the necessary possession of a high intelligence4 ,sensations are modified by use4 ,they become more acute and powerful by moderate exercise2 or1 they are dulled by undue excitement4 ,the former is shown by the acute hearing of the ,indian1 by the sharp sight of the sailor1 and by the delicate touch of the blind4 ,the latter is exemplified by the impaired hearing of the boiler-maker1 and the depraved taste of him who uses pungent condiments with his food4 ,again1 impressions habitually presented may not be consciously felt2 as is the case with the rumbling of carriages in a neighboring #agi street1 or the regular ticking of a clock4 ,all sensations become less vivid with the advance of age1 especially hearing and vision4 ,sidenote3 #e4 ,general sensibility8 ,what have we seen as regards the brain8 ,of what other structures is the same true8 #e4 ,,general ,,sensibility4--,there is a property possessed by nearly all parts of the human body which we call general sensibility4 ,we have recently seen that the brain is wholly insensitive1 and may be cut or pinched without pain4 ,the same is true of the nails1 hair1 the scarf-skin or external covering of the body1 and a few other structures4 ,in these parts no nerves are found4 ,on the other hand1 the sensibility of the true skin1 and of mucous membranes1 as of the eye and nose1 is exquisite1 these organs having a large supply of sensory nerve-fibres4 ,the bones and tendons have less of these fibres1 and are only moderately sensitive4 ,sidenote3 #f4 ,the cause of sensibility8 ,painful part in a surgical operation8 ,benumbing the surface8 ,how done by ether8 #f4 ,the sensibility of any part of the body1 then1 depends upon the number of nerves present2 and1 as a rule1 the nervous supply is proportional to the importance of the part1 and to its liability to injury4 ,when1 therefore1 a surgical operation is performed1 the most painful part of it is the incision through the skin2 the muscles1 cartilage1 and bone being comparatively without sensation4 ,hence1 if we could benumb the surface1 certain of the lesser operations might be undergone without great inconvenience4 ,this is1 in fact1 very successfully accomplished by means of the cold produced by throwing a spray of ether1 or of some other rapidly evaporating liquid1 upon the part to be cut4 ,sidenote3 #g4 ,tickling8 ,internal sensations8 ,the nerves of general sensibility8 #g4 ,tickling is a modification of general sensibility4 ,at first1 it excites a pleasurable sensation1 but this soon passes into pain4 ,it is only present in those parts where the sense of touch is feeble4 ,but all impressions are not received from without3 there are1 also1 certain internal #ahj sensations1 as they are called1 which depend upon the condition of the internal organs1 such as appetite1 hunger1 thirst1 the sense of satisfaction after taking food1 dizziness when looking down from some lofty position1 lassitude1 drowsiness1 fatigue1 and other feelings of comfort or discomfort4 ,general sensibility1 whether of the internal or external organs of the body1 chiefly depends upon the sensory fibres of the spinal nerve4 ,the face1 however1 is supplied by the sensory cranial nerves4 ,the sympathetic system has a low grade of feeling in health2 but disease in the parts served by it arouses an intense degree of pain4 ,sidenote3 #h4 ,connection between pain and sensibility8 #h4 ,,the ,,sensation ,,of ,,pain4--,what then is pain8 ,is it identical with ordinary sensibility8 ,there seems to be some necessary connection between the two feelings1 for they take place through the same channels1 and they are alike intense in the same situations4 ,but sensibility habitually contributes to our sources of pleasure1 the very opposite of pain2 hence1 these feelings cannot be identical4 ,sidenote3 #i4 ,explain the difference between pain and sensibility4 #i4 ,pain must1 therefore1 be a modification of the general sensibility1 which follows an excessive degree of excitement of the nerves2 there being a natural limit to the amount of stimulation which they will sustain4 ,so long as this limit is observed1 the part excited may be said to be simply sensitive2 but when it is exceeded1 the impression becomes painful4 ,this difference between sensibility and pain is well shown by the effects of sunlight upon the eye4 ,the indirect illumination of the sun arouses only the former feeling1 and is indispensable to our comfort and existence2 while the direct ray received into the eye occasions great pain4 ,sidenote3 #aj4 ,dread of pain8 ,how may its value be appreciated8 ,example4 #aj4 ,,the ,,uses ,,of ,,pain4--,the dread of pain is a valuable monitor to the body4 ,it puts us on our guard in the presence of danger2 teaches moderation in the use of our #aha powers2 indicates the approach of disease2 and calls attention to it when present4 ,the word disease1 in fact1 according to its original use1 had reference simply to the pain1 or want of ease1 which commonly attends disordered health4 ,when we observe the serious mishaps which occur when sensibility and pain are absent1 we cannot fail to appreciate its value4 ,for example1 a paralytic in taking a foot-bath1 forgets to test its temperature1 and putting his limbs into water while it is too hot1 is severely scalded without knowing it4 ,sidenote3 #aa4 ,the case of the traveller8 ,grain of sand8 ,the sun and child8 #aa4 ,a traveller1 overcome by cold and fatigue1 lies down and falls asleep near a large fire1 and when he is aroused in the morning1 it is discovered that one of his feet has been insensibly destroyed4 ,a grain of sand1 lodging in an insensitive eye1 may cause inflammation and even the loss of sight4 ,if intense light were not painful to the eye1 many a child would innocently gaze upon the glories of the sun to the ruin of his sight4 ,sidenote3 #ab4 ,mission of pain8 ,painful impressions compared with those of pleasure8 #ab4 ,pain is1 indeed1 a present evil1 but its relations with the future prove its mission merciful4 ,painful impressions cannot be recollected from past experience2 and they cannot be called into existence by the fancy4 ,considered in the light of results1 pain has a use above that of pleasure2 for while the immoderate pursuit of the latter leads to harm1 the tendency of pain is to restrict the hurtful courses of life1 and in this manner to protect the body4 ,sidenote3 #ac4 ,what does ,magendie say of the relation of pain to pleasure8 #ac4 ,the relations of pain to pleasure are thus described by the eminent physiologist1 ,magendie3--,by these sensations ,nature induces us to concur in the order which she has established among organized beings4 ,though it may appear like sophistry to say that pain is the shadow of pleasure1 yet it is certain that those who have exhausted the ordinary sources of pleasure have recourse to the #ahb causes of pain1 and gratify themselves by their effects4 ,do we not see in all large cities1 that men who are debauched and depraved find agreeable sensations1 where others experience only intolerable pain8 ,sidenote3 #ad4 ,the law of ,nature as regards painful sensations among animals8 #ad4 ,as to painful sensation among the inferior animals1 the plan of ,nature seems to be1 that the higher the intelligence of the creature1 and the more complete its power of defence1 the more acute is its sensibility4 ,we infer1 therefore1 that animals low in the scale of existence1 and helpless1 are not very liable to suffer pain4 ,sidenote3 #ae4 ,the sensation of contact and pain8 ,special sensations of man8 ,how regarded8 #ae4 ,,special ,,sensation4--,the sensations of simple contact and pain are felt by nearly all parts of the system1 whether external or internal1 and are the necessary consequence of the general sensibility2 but1 so far as the objects which surround us are concerned1 these impressions are vague and passive in character1 and inform the mind of none of the properties or powers of these objects4 ,besides these feelings1 therefore1 man is endowed with certain special sensations1 which are positive and distinct in character1 and which he can call into exercise at will1 and employ in the pursuit of knowledge4 ,for reasons relating to the original constitution of the body1 these sensations are to be regarded as modifications of the general sensibility already alluded to1 constructed with special reference to the different forces of ,nature1 of which we have any knowledge1 such as heat1 motion1 gravity1 sunlight1 and the like4 ,sidenote3 #af4 ,what are the special senses8 ,special organs for them8 #af4 ,these distinct and active faculties are termed the special senses1 and are five in number1 viz41 ,touch1 ,taste1 ,smell1 ,sight1 and ,hearing4 ,for the exercise of these senses1 special organs are furnished1 such as the hand1 the tongue1 the nose1 the eye1 and the ear4 ,the manner in which the nerves of special sense terminate1 varies in the #ahc case of each organ1 so that each is adapted to one set of sensations alone1 and is incapable of perceiving any other4 ,thus the nerve of hearing is excited by the undulations of sound1 and not by those of light1 while the reverse is true of the nerve of sight2 and the nerve of smell can appreciate neither of them1 being capable only of taking cognizance of the odorous properties of bodies4 ,sidenote3 #ag4 ,what is said in relation to one more than the five senses8 #ag4 ,by some writers six senses are accorded to man2 the additional one being either the sense of temperature1 for as we shall presently see this is not the same as touch2 or according to others1 the muscular sense by which we are enabled to estimate the weights of bodies4 ,the latter also differs in some respects from the sense of touch4 ,sidenote3 #ah4 ,the sense of touch1 how prevalent8 ,what is said of the hand8 #ah4 ,,organs ,,of ,,touch4--,the sense of touch is possessed by nearly all portions of the general surface of the body1 but it finds its highest development in the hands4 ,the human hand is properly regarded as the model organ of touch4 ,the minute structure of the skin fits it admirably for this form of sensation3 the cuticle1 or scarf-skin1 is fine and flexible1 while the cutis1 or true skin1 contains multitudes of nerve-filaments1 arranged in rows of papill1 or cone-like projections1 about one-hundredth of an inch in length4 ,it is estimated that there are #bj1jjj of these papill in a square inch of the palmar surface of the hand4 ,now1 although the nerves of the cutis are the instruments by which impressions are received and transmitted to the brain1 yet the cuticle is essential to the sensation of touch4 ,this is shown by the fact that whenever the true skin is laid bare1 as by a burn or blister1 the only feeling that it experiences from contact is one of pain1 not that of touch4 ,sidenote3 #ai4 ,office of the cuticle8 ,tips of the fingers8 ,the fingers with thumb8 #ai4 ,the office of the cuticle is thus made evident3 it is to shield the nerve filaments from direct contact with #ahd external objects4 ,at the tips of the fingers1 where touch is most delicate1 the skin rests upon a cushion of elastic material1 and receives firmness and permanence of shape by means of the nail placed upon the less sensitive side4 ,besides these favorable conditions1 the form of the arm is such1 and its motions are so easy and varied1 that we are able to apply the test of touch in a great number of directions4 ,the slender1 tapering fingers1 with their pliant joints1 together with the strong opposable thumb1 enable the hand to mold itself upon and grasp a great variety of objects2 so that great as are the delicacy and grace of the hand1 it is not wanting in the elements of power4 ,sidenote3 #bj4 ,what special importance is attributed to the hand8 #bj4 ,its beauty and adaptation to the wants of man have made the hand an attractive theme for philosophers4 ,they do not1 however1 always agree in their conclusions4 ,one has the opinion that man has acquired his intelligence and achieved his place as lord of creation1 because he has this organ4 ,buffon1 in effect1 declares that with fingers twice as numerous and twice as long1 we would become proportionally wiser2 but ,galen long ago took a more reasonable view1 when he taught that man is the wisest of animals1 not because he possesses the hand2 but because he is the wisest and understands its use1 the hand has been given to him2 for his mind1 not his hand has taught him the arts4 ,another has well said1 that no one can study carefully the human hand and fail to be convinced of the existence of the ,deity4 ,sidenote3 #ba4 ,the simplicity of touch8 ,what does it teach us8 #ba4 ,,the ,,sense ,,of ,,touch4--,touch is the simplest of the senses4 ,it is that which the child first calls into exercise in solving the early problems of existence2 and it is that which is in the most constant use throughout life4 ,we are brought by the touch into the most intimate relations with external objects1 and by it we learn the greater number1 if not the most important1 of the properties of #ahe these objects2 such as size1 figure1 solidity1 motion1 and smoothness or roughness of surface4 ,sidenote3 #bb4 ,importance of the sense of touch to the development of the other senses8 #bb4 ,the sense of touch assists the other senses1 especially that of sight1 giving foundation and reality to their perceptions4 ,without it1 the impressions received by the eye would be as vague and unreal as the figures that float through our dreams4 ,a boy who had been blind from birth1 at the age of twelve years received sight by means of a surgical operation3 at first1 he was unable to distinguish between a globe and a circular card1 of the same color1 before he had touched them4 ,after that1 he at once recognized the difference in their form4 ,he knew the peculiarities of a dog and a cat by feeling1 but not by sight1 until one day1 happening to take up the cat1 he recognized the connection of the two sorts of impressions1 those of touch and sight2 and then1 putting the cat down1 he said3 ,so1 puss1 ,i shall know you next time4 ,illustration3 ,,fig4 #de4 ,sidenote3 #bc4 ,liability of touch to err8 ,describe the illustration4 #bc4 ,touch is considered the least liable to error of all the senses2 yet1 if that part of the skin by which the sense is exercised is removed from its customary position1 a false impression may be created in the mind4 ,this is well illustrated by an experiment1 which dates from the time of ,aristotle4 ,if we cross the middle finger behind the #ahf forefinger1 and then roll a marble1 or some small object1 upon the tips of the fingers 7see ,fig4 #de71 the impression will be that two marbles are felt4 ,if the fingers1 thus transposed1 be applied to the end of the tongue1 two tongues will be felt4 ,when the nose is accidentally destroyed1 the surgeon sometimes performs an operation for the purpose of forming a new one1 by transplanting a partially removed piece of the skin of the forehead upon the injured part3 then1 if the new nose be touched or pinched1 the feeling is referred to the forehead4 ,this fact illustrates one important truth1 that the nerves will re-unite after they have been cut1 and feeling will be restored3 if it were otherwise1 a succession of slight cuts upon the fingers would seriously impair their tactile sensibility4 ,sidenote3 #bd4 ,the delicacy of touch8 ,experiments with a pair of compasses8 #bd4 ,,the ,,delicacy ,,of ,,touch4--,although the hand is the proper organ of this sense1 yet it is exercised by various parts of the body1 their degree of sensibility being proportional to the number of papill they contain4 ,the varying degrees of tactile delicacy of the different parts of the surface have been measured1 in an ingenious manner1 by means of a pair of compasses1 tipped with small pieces of cork4 ,the two points of the compasses are touched at the same moment to the skin1 the eyes being closed1 and it is found that1 in sensitive parts1 the distance between the points may be quite slight1 and yet each be plainly felt2 while1 in less sensitive parts1 the points of the compasses are felt as a single point1 although they are separated one or two inches4 ,sidenote3 #be4 ,further experiments and results8 #be4 ,at the tips of the fingers1 the distance between the points being one-twentieth of an inch1 a double impression is felt4 ,the distance must be twice as great1 for the palm2 four times as great1 for the lips2 and1 on the forehead1 it must be twenty times greater4 ,at the middle of the back1 where the touch is least acute1 the points must be #ahg separated more than two inches before they can be separately felt4 ,therefore1 the sense of touch in the fingers is said to be fifty times more delicate than upon the posterior surface of the body4 ,sidenote3 #bf4 ,exquisite delicacy of touch8 ,the same among the blind8 #bf4 ,exquisite delicacy of touch is attained by practice4 ,this is shown in many of the lighter and more graceful employments of daily life4 ,without it1 the skill of the painter1 sculptor1 and musician would be rude indeed4 ,by training1 also1 the physician acquires the tactus eruditus1 or discriminating touch2 but among the blind1 delicacy of touch is most remarkable1 and it here finds its highest value2 for its possession1 in a measure1 compensates the loss of sight by enabling them to read1 by means of raised letters1 to work with certain tools1 and even to play upon musical instruments4 ,a person born without sight1 and without hearing or voice1 may1 by the education of the touch1 be rescued from apparent imbecility1 and be taught not only to read and write1 but even to perform household and other useful labors4 ,sidenote3 #bg4 ,rival candidates for the sixth sense8 ,give the two reasons on the subject4 #bg4 ,,sensations ,,of ,,temperature ,,and ,,weight4--,each of these sensations has been described by the physiologists as a special sense1 and they are rival candidates1 so to speak1 for the position and title of the sixth sense4 ,in the sensation of temperature1 or the thermal sense1 touch bears a part1 but the two feelings appear to be distinct4 ,in proof of this1 we observe1 firstly1 that they are not alike intense in the same situations2 as1 for example1 the skin of the face and elbow1 where the sense of touch is feeble1 is very sensitive to impressions of heat and cold4 ,secondly1 the ability to recognize temperature may be lost by paralysis1 while the sensibility of touch remains unaffected4 ,when the skin comes in contact with a very hot substance1 the sensation felt is that of pain1 not of touch4 ,in like manner1 a #ahh very cold substance causes pain1 not the feeling of cold4 ,so that a red-hot iron1 and solid carbonic acid 7the temperature of which is #ajh below zero71 feel alike2 and each1 if pressed slightly1 will produce a blister4 ,sidenote3 #bh4 ,the muscular sense8 ,state what is said to illustrate the subject4 #bh4 ,the muscular sense1 by some considered distinct from touch1 gives rise to the sensations of weight1 and other forms of external resistance4 ,that this feeling exists1 is shown by the following simple experiment4 ,if the hand be placed flat upon a table1 and a somewhat heavy weight be put into it1 touch alone is exercised and a feeling of pressure results2 but if the hand be raised1 a certain amount of muscular effort must be put forth1 and thus the sensation of weight is recognized4 ,through the muscular sense1 precision of effort is rendered possible2 for by it we learn to adjust the force exerted to the weight of the object to be lifted1 moved1 or carried4 ,without it1 all our movements would necessarily become ill-regulated and spasmodic4 ,in cases of disease1 where the sensibility of the lower limbs is lost1 while power of motion remains1 the patient is able to stand erect so long as he can see his limbs2 but just as soon as his eyes are closed1 he begins to waver1 and will fall unless supported4 ,sidenote3 #bi4 ,the organ of taste8 ,the tongue8 ,its powers of motion8 #bi4 ,,the ,,organ ,,of ,,taste4--,the tongue is the special organ of the sense of taste2 but the back part of the mouth also possesses this faculty4 ,the tongue is a muscular organ1 the muscles composing it being so numerous and interwoven as to give it the freedom and variety of motion which it possesses4 ,it can curve itself upward or downward2 it can extend or contract itself2 and1 with its point1 can sweep the cavity of the mouth1 in all directions1 in the search for scattered particles of food4 ,sidenote3 #cj4 ,peculiarities of the tongue8 ,uses of the papill8 #cj4 ,the upper surface of the tongue is peculiar1 being marked by the presence of innumerable papill1 some of #ahi which are of microscopic size1 resembling those that abound in the fingers1 and in other parts of the body that have the sense of touch4 ,others are much larger1 and give to the tongue its roughness of feeling and appearance4 ,through the medium of these papill1 the tongue receives impressions of touch and temperature1 as well as taste3 indeed1 its extremity is fully as delicate1 in respect to tactile sensations1 as the tips of the fingers themselves4 ,it can recognize the two points of the compasses when separated not more than one-twenty-fourth of an inch2 the back of it is much less sensitive to touch1 while at the same time it is more highly sensitive to impressions of taste4 ,sidenote3 #ca4 ,resemblance to the parts of the tongue8 ,powers and functions of the parts8 #ca4 ,each lateral half of the tongue resembles the other in structure1 and each receives the same number of nerves--three4 ,one of these regulates motion1 the other two are nerves of special sense4 ,one of the latter supplies the front half of the tongue1 and is called the gustatory nerve4 ,this is a branch of the great cranial nerve1 called the fifth pair1 which ramifies in all parts of the face4 ,the back of the tongue is endowed with the power of taste through a nerve known as the glosso-pharyngeal1 because it is distributed both to the tongue and throat4 ,this difference in the nervous supply of the tongue becomes significant1 when we learn1 as we shall presently1 that each part of it perceives a different class of flavors4 ,sidenote3 #cb4 ,taste8 ,what are the requisites to taste8 #cb4 ,,the ,,sense ,,of ,,taste4--,taste is the special sense by means of which we discover the savors1 or flavoring properties of the substances1 which come in contact with the tongue4 ,mere contact with the surface of the tongue1 however1 is not sufficient1 but contact with the extremities of the nerves of taste within the papill is required4 ,in order that the substance to be tasted may penetrate the #aij cells covering the nerves1 it must either be liquid in form1 or readily soluble in the watery secretion of the mouth1 the saliva4 ,the tongue must be moist also4 ,if the substance be insoluble1 as glass or sand1 or the tongue dry1 the sense of taste is not awakened4 ,in sickness1 when the tongue is heavily coated1 the taste is very defective1 or1 as is frequently expressed1 nothing tastes aright4 ,sidenote3 #cc4 ,portions of the tongue endowed with taste8 ,where else does the sense lodge8 ,what is stated in respect to sweet and bitter flavors8 ,reflex effects mentioned8 #cc4 ,all portions of the tongue are not alike endowed with the sense of taste1 that function being limited to the posterior third1 and to the margin and tip of this organ4 ,the soft palate1 also1 possesses the sense of taste2 hence1 an article that has an agreeable flavor may very properly be spoken of as palatable1 as is often done4 ,all parts of the tongue do not perceive equally well the same flavors4 ,thus1 the front extremity and margin1 which is the portion supplied by the fifth pair of nerves1 perceives more acutely sweet and sour tastes2 but the base of the tongue1 supplied by the glosso-pharyngeal nerve1 is especially sensitive to salt and bitter substances4 ,the nerve of the front part of the tongue1 as before stated1 is in active sympathy with those of the face1 while the relations of the other nerve are chiefly with the throat and stomach2 so that when an intensely sour taste is perceived1 the countenance is involuntarily distorted1 and is said to wear an acid expression4 ,on the other hand1 a very bitter taste affects certain internal organs1 and occasions a sensation of nausea1 or sickness of the stomach4 ,sidenote3 #cd4 ,what is stated of the relations of taste with other senses8 #cd4 ,,relations ,,of ,,taste ,,with ,,other ,,senses4--,taste is not a simple sense4 ,certain other sensations1 as those of touch1 temperature1 smell1 and pain1 are blended and confused with it2 and certain so-called tastes are really sensations of another kind4 ,thus an astringent taste1 like that of alum1 is more properly an astringent feeling1 and #aia results from an impression made upon the nerves of touch1 that ramify in the tongue4 ,in like manner1 the qualities known as smooth1 oily1 watery1 and mealy tastes1 are dependent upon these same nerves of touch4 ,a burning or pungent taste is a sensation of pain1 having its seat in the tongue and throat4 ,a cooling taste1 like that of mint1 pertains to that modification of touch called the sense of temperature4 ,sidenote3 #ce4 ,its dependence on smell8 on sight8 #ce4 ,taste is largely dependent upon the sense of smell4 ,a considerable number of substances1 like vanilla1 coffee1 and garlic1 which appear to possess a strong and distinct flavor1 have in reality a powerful odor1 but only a feeble taste4 ,when the sense of smell is interfered with by holding the nose1 it becomes difficult to distinguish between substances of this class4 ,the same effect is frequently observed when smell is blunted during an ordinary cold in the head4 ,sight also contributes to taste4 ,with the eyes closed1 food appears comparatively insipid2 and a person smoking tobacco in the dark is unable to determine by the taste whether his cigar is lighted or not4 ,accordingly1 it is not a bad plan to close the nose and shut the eyes when about to swallow some disagreeable medicine4 ,sidenote3 #cf4 ,the chief use of the sense of taste8 ,the position of its organs8 ,the rule as regards wholesome and unwholesome food8 ,remarks respecting the rule8 #cf4 ,,influence ,,of ,,education ,,on ,,the ,,taste4--,the chief use of the sense of taste appears to be to act as a guide in the selection of proper food4 ,hence its organs are properly placed at the entrance of the digestive canal4 ,as a general rule1 those articles which gratify the taste are wholesome2 while the opposite is true of those which impress it disagreeably4 ,this statement is more exact in reference to the early years of life than to later years1 when1 by reason of mischievous habits1 the sense of taste has become dulled or perverted4 ,the desires of a child are simple2 he is fully satisfied with plain and wholesome articles of diet1 and must usually learn to like those #aib which have a strongly marked flavor4 ,accordingly1 it is far easier at this age to encourage the preference for plain food1 and thus establish healthful habits1 than later in life to uproot habits of indulgence in stimulating substances1 after their ill effects begin to manifest themselves4 ,sidenote3 #cg4 ,diversity in tastes of men8 ,how shown8 ,the education of the sense of taste8 #cg4 ,the tastes of men present the most singular diversities1 partly the result of necessity and partly of habit or education4 ,the ,esquimaux like the rank smell of whale oil1 which is a kind of food admirably suited to the requirements of their icy climate2 and travellers who go from our climate to theirs are not slow to develop a liking for the same articles that the natives themselves enjoy4 ,the sense of taste is rendered very acute by education1 as is shown in an especial manner by those who become professional tasters of tea and wine4 ,sidenote3 #ch4 ,location of the sense of smell8 ,the nose8 ,roof of the mouth8 #ch4 ,,the ,,sense ,,of ,,smell--,,the ,,nasal ,,cavities4--,the sense of smell is located in the delicate mucous membrane which lines the interior of the nose4 ,that prominent feature of the face1 the nose1 which is merely the front boundary of the true nasal organ1 is composed partly of bone and partly of cartilage4 ,the upper part of it is united with the skull by means of a few small bones2 to which circumstance is due its permanence of shape4 ,the lower portion1 or tip of the nose1 contains several thin pieces of cartilage1 which render it flexible and better able to resist the effects of blows and pressure4 ,behind the nose we find quite a spacious chamber1 separated from the mouth by the hard palate1 forming the roof of the mouth1 and by the soft palate 7see ,fig4 #df72 and divided into two cavities by a central partition running from before backward4 ,sidenote3 #ci4 ,cavities of the nose8 ,obstruction of the passage of air through them8 #ci4 ,these nasal cavities1 constituting the true beginning of the air-passages1 extend from the nose backward to the #aic upper opening of the throat1 and rise as high as the junction of the nose with the forehead4 ,the inner wall of each cavity is straight and smooth2 but from the outer wall there jut into each cavity three small scroll-like bones4 ,the structure of these bones is very light1 and hence they have been called the spongy bones of the nose4 ,in this manner1 while the extent of surface is greatly increased by the formation of these winding passages1 the cavities are rendered extremely narrow2 so much so1 in fact1 that a moderate swelling of the mucous membrane which lines them1 as from a cold1 is sufficient to obstruct the passage of air through them4 ,illustration3 ,,fig4 #df4--,,section ,,of ,,the ,,right ,,nasal ,,cavity4 ,sidenote3 #dj4 ,the special nerve of smell8 ,its location8 #dj4 ,,the ,,nerve ,,of ,,smell4--,the internal surface of the nasal passages is covered by a delicate and sensitive mucous membrane4 ,its surface is quite extensive1 following as it does1 all the inequalities produced by the curved spongy bones of the nose4 ,the upper portion of it alone is the seat of smell1 since that part alone receives branches from the first pair of cranial nerves1 or the olfactory nerve1 which is the special nerve of smell 7see ,fig4 #dc74 ,in ,fig4 #df is shown the distribution of this nerve1 in the form of an intricate network upon the two upper spongy bones4 ,the nerve itself 7#a7 does not issue from the skull1 but rests upon a thin bone which separates it from the cavity of the nose2 and the branches which proceed from it pass through this bone by means of numerous small openings4 ,the #aid engraving represents the outer surface of the right nasal cavity2 the three wave-like inequalities1 upon which the nervous network is spread out1 are due to the spongy bones4 ,the left cavity is supplied in the same manner4 ,sidenote3 #da4 ,branches of the fifth pair of nerves8 ,nasal mucus8 ,birds8 #da4 ,the nerves which ramify over the lower part of the membrane1 and which endow it with sensibility to touch and pain1 are branches of the fifth pair of nerves4 ,an irritation applied to the parts where this nerve is distributed occasions sneezing1 that is1 a spasmodic contraction of the diaphragm2 the object of which is the expulsion of the irritating cause4 ,the manner in which the olfactory nerve-fibres terminate is peculiar4 ,unlike the extremities of other nerves1 which are covered in by a greater or less thickness of tissue1 these come directly to the surface of the mucous membrane1 and thus come into very close contact with the odorous particles that are carried along by the respired air4 ,the surface is at all times kept in a moist condition by an abundant flow of nasal mucus2 otherwise it would become dry1 hard1 and insensitive from the continual passage of air to and fro in breathing4 ,birds1 which respire more actively than men1 have a special gland1 for secreting a lubricating fluid1 located in the air-passages of the head4 ,sidenote3 #db4 ,smell8 ,touch8 ,taste8 ,design of smell8 ,invisible and gaseous particles8 ,the extreme fineness of the particles8 ,musk8 ,in other cases8 #db4 ,,the ,,uses ,,of ,,the ,,sense ,,of ,,smell4--,smell is the special sense which enables us to appreciate odors4 ,touch1 as we have seen1 is largely concerned with solid bodies2 and taste1 with fluids1 or with solids in solution4 ,smell1 on the other hand1 is designed to afford us information in reference to substances in a volatile or gaseous form4 ,invisible and subtile particles emanate from odorous bodies1 and are brought by the respired air in contact with the terminal filaments of the olfactory nerve1 upon which an agreeable or disagreeable impression is produced4 #aie ,the fineness of the particles that constitute odors is often so extreme1 that they elude all attempts to measure or weigh them4 ,a piece of musk1 for instance1 may be kept for several years1 constantly emitting perfume1 without any appreciable loss of weight4 ,in other cases1 a loss of substance is perceptible1 such as the essential oils1 which enter into the composition of the ordinary perfumes4 ,sidenote3 #dc4 ,aid given by smell8 ,the highest use of the sense8 ,explain the manner4 #dc4 ,smell1 like taste1 aids us in the choice of proper food1 leading us to reject such articles as have a rank or putrid odor1 and which are1 as a rule1 unfit to be eaten4 ,the highest usefulness of this sense1 however1 consists in the protection it affords to the organs of respiration4 ,stationed at the gateways of the air-passages1 it examines the current of air as it enters1 and warns us of the presence of noxious gases1 and of other and generally invisible enemies to health4 ,not all dangerous vapors are offensive1 but almost all offensive vapors are unfit to be breathed4 ,a number of small stiff hairs grow from the margin of the nostrils to prevent the entrance of dust and other atmospheric impurities1 which would be alike injurious to the olfactory mucous membrane and to the lungs4 ,the benevolent design of the ,maker of our bodies may be observed in all parts of their mechanism2 but1 probably1 in none is it more clearly displayed than in connection with the sense of smell4 ,sidenote3 #dd4 ,sense of smell in the inferior animals8 ,how1 and in what cases1 illustrated8 #dd4 ,the sense of smell is developed in a remarkable degree in certain of the inferior animals1 and is especially acute in reference to the peculiar emanations that appear to characterize the different animals4 ,the lion and other carnivorous beasts scent their prey from a great distance2 and the fox-hound is able to track the fox through thickets and over open country for many miles2 while the timid1 helpless herbivora1 such as the deer and sheep1 find in the #aif sense of smell a means of protection against their natural enemies1 of whose approach they are in this manner warned4 ,by training this sense in the dog1 and making it subservient to his use1 man is able to hunt with success certain shy and very fleet animals1 which otherwise he could but seldom approach4 ,among men1 individuals differ greatly in respect to the development of this sense2 and especially in certain savage tribes it is found to be extremely delicate4 ,humboldt states that the natives of ,peru can1 by this sense1 distinguish in the dark between persons of different races4 ,sidenote3 #de4 ,what is sight8 ,what information does it furnish8 ,composite visual sensations8 #de4 ,,the ,,sense ,,of ,,sight4--,sight1 or ,vision1 is the special sense by means of which we appreciate the color1 form1 size1 distance1 and other physical properties of the objects of external nature4 ,primarily1 this sense furnishes us with information concerning the different shades of color and the different degrees of brightness3 these are the simple sensations of sight1 such as the yellowness and glitter of a gold coin4 ,in addition to these1 there are composite visual sensations1 produced by the joint action of the other senses and by the use of the memory and judgment2 such as1 in the case of the coin1 its roundness1 solidity1 size1 its distance and direction from us4 ,so that many of our sensations1 commonly considered as due to sight1 are in reality the results of intellectual processes which take place instantaneously and unconsciously4 ,sidenote3 #df4 ,comparison between sight and hearing8 ,relative capacity of deaf and blind8 #df4 ,this faculty not only has value in the practical every-day affairs of life1 but it contributes so largely to the culture of the intellect and to our higher forms of pleasure1 that some writers are disposed to rate it as the first and most valuable of the senses4 ,others1 however1 maintain that the sense of hearing does not yield in importance to that of sight2 and they cite in support of their position #aig the fact that the blind are commonly cheerful and gay1 while the deaf are inclined to be morose and melancholy4 ,in respect to the relative capacity for receiving education in the deaf and blind1 it is found that the former learn more quickly1 but their attainments are not profound2 while the blind acquire more slowly1 but are able to study more thoroughly4 ,sidenote3 #dg4 ,sight1 unlike the other senses8 ,in the case of the stars8 #dg4 ,,light4--,,the ,,optic ,,nerve4--,unlike the senses previously considered--touch1 taste1 and smell--sight does not bring us into immediate contact with the bodies that are examined2 but1 by it1 we perceive the existence and qualities of objects that are at a greater or less distance from us4 ,in the case of the stars1 the distance is incalculable1 while the book we read is removed but a few inches4 ,light is the agent which gives to this sense its wide range4 ,the nature of this mysterious force is not known1 and it is not here to be discussed2 since its study belongs more properly to the province of natural philosophy4 ,sidenote3 #dh4 ,the undulatory theory of light8 ,what does the theory suppose8 #dh4 ,it is sufficient1 in this connection1 to state that the theory of light now generally accepted1 and which best explains the facts of optics1 is that known as the undulatory theory4 ,this theory supposes that there exists an intangible1 elastic medium1 which fills all space1 and penetrates all transparent substances1 and which is thrown into exceedingly rapid undulations or waves1 by the sun and every other luminous body2 the undulations being propagated with extreme rapidity1 and moving not less than #ahf1jjj miles in a second4 ,sidenote3 #di4 ,the sensation of light8 ,optic nerve8 #di4 ,these waves are thought to produce in the eye the sensation of light1 in the same manner as the sonorous vibrations of the air produce in the ear the sensation of sound4 ,that part of the eye which is sensitive to these waves is the expansion of the optic nerve4 ,it is sensitive #aih to no other impression than that of light1 and it is the only nerve which is acted upon by this agent4 ,the optic nerve1 also called the second pair of cranial nerves1 is the means of communication between the eye and the brain4 ,sidenote3 #ej4 ,the two nerves constituting the pair of nerves8 #ej4 ,the two nerves constituting the pair1 arise from ganglia lying at the base of the cerebrum1 one of them on each side2 from which points they advance to the eyes1 being united together in the middle of their course in the form of the letter ,x 7,fig4 #dc--b74 ,by this union the two eyes are enabled to act harmoniously1 and in some respects to serve as a double organ4 ,and by reason of this same intimate nervous communication1 when serious disease affects one eye1 the fellow-eye is extremely liable to become the seat of sympathetic inflammation2 and this1 if neglected1 almost certainly results in hopeless blindness4 ,sidenote3 #ea4 ,why is the eye called the window of the soul8 ,why1 the subject of enthusiastic study8 #ea4 ,,the ,,organ ,,of ,,sight4--,,the ,,eye4--,the proximity of the eye to the brain1 and the important part it performs in giving expression to the emotions1 have given it the name of the window of the soul4 ,the exceeding beauty of its external parts1 and the high value of its function1 have long made this organ the subject of enthusiastic study4 ,it is chiefly within the last twenty years1 however1 that this study has been successful and fruitful of practical results4 ,several ingenious instruments have been invented for the examination of the eye in health and disease1 and new operations have been devised for the relief of blindness and of impaired vision4 ,as a result1 it is now a well-marked fact that1 in civilized lands1 the number of those who suffer from loss of sight is proportionally much less than in countries where science is less known and cultivated4 ,sidenote3 #eb4 ,the most obvious fact8 ,the consequence8 ,the next thing noticed8 ,its range of view8 ,of what does the organ of vision consist8 #eb4 ,the most obvious fact in respect to the apparatus of #aii sight is that there are two eyes1 which may either act together as one1 and be fixed upon one object1 or one eye may be used independently of the other4 ,in consequence of this arrangement the loss of one eye does not necessitate blindness1 and1 in fact1 it not infrequently happens that the sight of one eye may be long impaired or lost before the fact is discovered4 ,we next notice that it is placed at the most elevated part of the body1 in front1 and near the brain4 ,it also commands a wide range of view1 being itself moved with great rapidity1 and being further aided by the free motion of the head and neck4 ,the organ of vision consists essentially of two parts3 the optical instrument itself--the eyeball--and its enveloping parts1 or the case in which the instrument is kept free from harm4 ,the latter1 which are external1 and which we shall first consider1 are chiefly the ,orbits1 the ,eyelids1 and the apparatus for the ,tears4 ,sidenote3 #ec4 ,the protection of the eyeball against injury8 ,the overhanging brow8 ,the opening for the optic nerve8 #ec4 ,,the ,,orbits4--,the eyeball1 which is a delicate organ1 is well defended against external injury within the orbits or bony sockets of the head4 ,these are deep conical hollows1 bounded in part by the bones of the skull1 and in part by those of the nose and cheek4 ,the orbit juts out beyond the most exposed portion of the eyeball1 as may be seen by laying a book over the eye1 when it will be found that no part of the eyeball1 unless it be very prominent1 will be touched by the book2 so that the only direction in which an injury is liable to be received is immediately in front of the eye4 ,the overhanging brow is itself covered by a layer of thick skin1 studded with short1 stout hairs1 which are so bent as to prevent the perspiration from running into the eye and obscuring vision4 ,through a hole in the bottom of the orbit1 the nerve of sight passes outward from the brain4 ,the orbit also contains a considerable amount of a fatty tissue1 upon which1 as upon an elastic cushion1 the eye rests4 #bjj ,illustration3 ,,fig4 #dg4--;,,front ,,view ,,of ,,right ,,eye4 7,natural ,size47 #a4 ,the ,lachrymal1 or tear gland1 lying beneath the upper eyelid4 #b4 ,the ,nasal ,duct is shown by the dotted line4 ,the 99 marks the orifice in the lower lid4 ,the central black spot is the pupil2 surrounding it is the iris2 and the triangular white spaces are the visible portion of the sclerotic4 ,sidenote3 #ed4 ,what are the eyelids8 ,the upper lid8 ,the lower one8 ,the mucous membrane of the eye8 #ed4 ,,the ,,eyelids4--,the eyelids are two movable curtains1 or folds1 which1 when shut1 cover the front part of the orbit1 and hide the eye from view4 ,the upper lid is the larger1 has a curved margin1 and moves freely1 while the lower lid is comparatively short and straight1 and has but a slight degree of motion 7,fig4 #dg74 ,skin covers the exterior of the lids1 while a fine mucous membrane lines their inner surface1 and is likewise spread out over the entire front of the eyeball4 ,this membrane1 which is called the ,conjunctiva1 is highly sensitive1 and thus plays an important part in protecting the eye against the lodgment of sand1 ashes1 chaff1 and other foreign particles that are blown about in the air4 ,this sensitive membrane will not endure the presence of these particles4 ,if any find access1 it causes a constant winking1 a flow of tears1 and other signs of irritation1 until it is removed4 ,sidenote3 #ee4 ,the eyelashes8 ,the little points within the line of the lashes8 ,of what use are these glands8 #ee4 ,the long1 silky eyelashes1 which garnish the edges of the lids1 act like a sieve to prevent the entry of dust and the like2 and together with the lids1 they regulate the amount of light which is permitted to enter the eye1 so that it is shielded from a sudden flood or glare of light4 ,the little points seen in the figure just within the line of the lashes1 especially on the lower lid1 represent the mouths of numerous little sebaceous glands 7,fig4 #dh1 ,d1,d71 such as are always #bja found in the neighborhood of hairs4 ,these glands supply a thick1 oily material which greases the edges of the lids and prevents their adhering together1 and likewise prevents the overflow of the tears upon the cheek4 ,sidenote3 #ef4 ,the location of the lachrymal gland8 ,the use of the gland8 #ef4 ,,the ,,lachrymal ,,fluid1 ,,or ,,the ,,tears4--,just within the outer part of the bony arch of the brow1 where the bone may be felt to be sharper than in other positions1 is lodged a little organ called the lachrymal gland1 the situation of which is indicated in ,fig4 #dg1 #a4 ,this is the gland whence flows the watery secretion1 commonly called the tears1 which is designed to perform an exceedingly important duty in lubricating the lids1 and in keeping the exposed surface of the eyeball moist and transparent4 ,for1 without this or some similar liquid1 the front of the eye would speedily become dry and lustreless1 like that of a fish which has been removed from the water3 the simple exposure of the eye to the air would then suffice to destroy vision4 ,sidenote3 #eg4 ,when does the secretion of the tears occur8 ,the secretion not used for the eye8 ,location of the nasal duct8 ,its use8 ,the overflow of tears in old people8 #eg4 ,this secretion of the tears takes place at all times1 during the night as well as the day2 but it is seldom noticed1 except when under the influence of some strong mental emotion1 whether of sorrow or happiness1 it is poured forth in excess1 so as to overflow the lids4 ,strong light or a rapid breeze will1 among many other causes1 excite the flow of the tears4 ,that portion of this secretion which is not used in moistening the eye is carried off into the nose by a canal situated near the inner angle of the eye1 called the nasal duct4 ,this duct is shown in ,fig4 #dg1 #b1 and is connected with each lid by delicate tubes1 which are indicated by dotted lines in the figure2 the asterisk marks the little opening in the lower lid1 by which the tears enter the nasal duct4 ,by gently turning the inner part of that lid downward1 and looking in a mirror1 #bjb this small lachrymal point may be seen in your own eye4 ,in old people1 these points become everted1 and do not conduct the tears to the nasal cavity1 so that they are inconvenienced by an overflow of tears upon the face4 ,illustration3 ,,fig4 #dh4--,,vertical ,,section ,,of ,,the ,,eye4 7,enlarged47 ,c1 ,the ,cornea4 ,a1 ,the ,aqueous ,humor4 ,i1 ,the ,iris4 ,p1 ,the ,pupil4 ,l1 ,the ,crystalline ,lens4 ,h1 ,the ,ligament of the ,lens4 ,b1 ,the ,ciliary ,process4 ,v1 ,the ,cavity containing the ,vitreous ,humor4 ,s1 ,the ,sclerotic4 ,ch1 ,the ,choroid4 ,r1 ,the ,retina4 ,n1 ,the ,optic ,nerve4 ,,dd1 ,the ,eyelids4 ,x1 ,the ,levator ,muscle of the ,upper ,lid4 ,y1 ,the ,upper ,straight ,muscle of the ,eye4 ,z1 ,the ,lower ,straight ,muscle4 ,sidenote3 #eh4 ,the watery fluid passing over the eyeball8 ,design of the arrangement8 ,winking8 #eh4 ,thus we observe that the gland which forms the tears is placed at the outer part of the eye1 while their means of exit is at the inner angle of the eye2 which fact renders it necessary that this watery fluid shall pass over the surface of the eyeball before it can escape4 ,this arrangement cannot be accidental1 but evinces design1 for it thus secures the perfect lubrication of the surface of the eye1 and cleanses it from the smaller particles of dust #bjc which may enter it1 in spite of the vigilance of the lids and lashes4 ,the act of winking1 which is generally unconsciously performed1 and which takes place six or more times in a minute1 assists this passage of the tears across the eye1 and is especially frequent when the secretion is most abundant4 ,sidenote3 #ei4 ,describe the shape of the eyeball4 ,its structure4 #ei4 ,,the ,,eyeball4--,the remarkable optical instrument called the eyeball1 or the globe of the eye1 upon which sight depends1 is1 as the name indicates1 spherical in shape4 ,it is not a perfect sphere1 since the front part projects somewhat beyond the rest1 and at the posterior part the optic nerve 7,fig4 #dh1 ,n7 is united to it1 resembling the junction of the stem with a fruit4 ,in its long diameter1 that is1 the horizontal or from side to side1 it measures a little more than an inch2 in other directions it is rather less than an inch4 ,in structure1 the ball of the eye is firm1 and its tense round contour may in part be felt by pressing the fingers over the closed lids4 ,sidenote3 #fj4 ,of what is the eyeball composed8 ,state how4 #fj4 ,the eyeball is composed chiefly of three internal1 transparent media1 called humors2 and three investing coats1 or tunics4 ,the former are the aqueous humor1 ,fig4 #dh1 ,a1 the crystalline lens ,l1 and the vitreous humor ,v4 ,of these the lens alone is solid4 ,the three coats of the eyeball are called the sclerotic ,s1 the choroid ,,ch1 and the retina ,r4 ,this arrangement exists in respect to five-sixths of the globe of the eye1 but in the anterior one-sixth1 these coats are replaced by the cornea ,c1 which is thin and transparent1 so that the rays of light pass freely through it1 as through a clear window-pane4 ,sidenote3 #fa4 ,the shape of the cornea8 ,its structure8 ,the white of the eye8 #fa4 ,in shape1 the cornea is circular and prominent1 resembling a miniature watch-glass1 about #a_/be of an inch thick4 ,in structure1 it resembles horn 7as the name signifies71 or the nail of the finger1 and is destitute of #bjd blood-vessels4 ,the ,sclerotic 7from scleros1 hard7 is composed of dense1 white fibrous tissue1 and gives to the eyeball its firmness of figure and its white color2 in front1 it constitutes the part commonly called the white of the eye4 ,it is one of the strongest tissues in the body2 it possesses very few vessels1 and is not very sensitive4 ,it affords protection to the extremely delicate interior parts of the eye2 and the little muscles which effect its movements are inserted into the sclerotic a short distance behind the cornea 7see ,fig4 #dh1 ,y1 ,z74 ,it is perforated posteriorly to admit the optic nerve4 ,sidenote3 #fb4 ,the second or middle coat of the eyeball8 ,its dark color8 #fb4 ,the ,choroid is the second or middle coat of the eyeball1 and lies closely attached to the inner surface of the sclerotic4 ,unlike the latter tunic1 its structure is soft and tender1 it is dark in color1 and possesses a great abundance of blood-vessels4 ,its dark color is due to a layer of dark brown or chocolate-colored cells spread out over its inner surface4 ,this dark layer serves to absorb the rays of light after they have traversed the transparent structures in front of it2 if the rays were reflected from side to side within the eye1 instead of being thus absorbed1 confused vision would result from the multitude of images which would be impressed upon the optic nerve4 ,sidenote3 #fc4 ,similar mechanism in microscopes8 ,the albinos8 ,white rabbits8 #fc4 ,this mechanism has been unconsciously imitated by the opticians1 who1 when they make a microscope or telescope1 take care that the interior of its tube shall be coated with a thick layer of black paint or lamp-black2 for without it1 a clear delineation of the object to be viewed is impossible4 ,the albinos1 in whom these dark cells of the choroid are wanting1 have imperfect vision1 especially in the daytime and in strong lights4 ,the dark cells are also wanting in white rabbits1 and other animals that have red or pink eyes2 their vision appears to be imperfect in the presence of a bright light4 #bje ,sidenote3 #fd4 ,what is the iris8 ,its construction8 ,how is the size of the pupil regulated8 #fd4 ,,the ,,iris4--,continuous with the choroid1 in the front part of the globe of the eye1 is a thin1 circular curtain1 which occasions the brown1 blue1 or gray color of the eye in different individuals4 ,on account of the varieties of its color1 this membrane has received the name ,iris1 which is the ,greek word for rainbow 7see ,fig4 #dh1 ,i74 ,a front view of it is shown in ,fig4 #dg4 ,the iris is pierced in its centre by a round opening1 called the pupil 7,p71 which is constantly varying in size4 ,in olden times it was spoken of as the apple of the eye4 ,the hinder surface of the iris1 except in albinos1 has a layer of dark coloring matter resembling that of the choroid4 ,the iris is a muscular organ1 and contains two distinct sets of fibres2 one of which is circular1 while the other radiates outward from the pupil4 ,the action of these sets of fibres regulates the size of the pupil2 for when the circular set acts1 the pupil contracts1 and when the other set acts1 the opening expands4 ,their action is involuntary1 and depends on the reflex system of nerves1 which causes the contraction of the pupil when a strong light falls upon the eye1 and its expansion when the illumination is feeble4 ,sidenote3 #fe4 ,the admission of light to the eye8 ,the action of the iris under different circumstances8 ,the lustre of the eye1 how affected in youth and old age8 #fe4 ,the iris1 accordingly1 serves a very useful purpose in regulating the admission of light to the eye4 ,it1 however1 does not act instantaneously2 and hence1 when we pass quickly from a dark room into the bright sunlight1 the vision is at first confused by the glare of light1 but as soon as the pupil contracts1 the ability to see becomes perfect4 ,on the other hand1 when we enter a dark apartment1 such as a cellar1 for a short time we can see nothing clearly2 but as soon as the pupil expands and admits more light1 we are enabled to distinguish the surrounding objects4 ,animals of the cat species1 and others which prowl around after nightfall1 are enabled to see in the dark by #bjf having the iris very dilatable4 ,the size of the pupil affects the lustre of the eye4 ,when it is large1 as it usually is during youth1 the eye appears clear and brilliant2 while in old age the pupil is small and the eye is dull4 ,the brilliancy of the eye is in part1 at least1 dependent upon the reflection of light from the front surface of the crystalline lens4 ,sidenote3 #ff4 ,means used to increase the beauty of the eye8 ,the injurious consequences8 #ff4 ,certain poisonous vegetables have the property of causing the pupil to dilate1 and have been used in small doses to increase the beauty of the eye4 ,one of these drugs has been so largely used by the ladies for this purpose1 that it has received the name belladonna1 from the ,italian words meaning beautiful lady4 ,this hazardous practice has resulted more than once in the death of the person desiring thus to increase her personal attraction4 ,the common ,english name for belladonna is deadly nightshade4 7,in the diagram on page #bad the shape and relations of the iris are more accurately shown than in the figure referred to above47 ,sidenote3 #fg4 ,what part does the retina constitute8 ,how formed8 ,its texture8 ,color8 ,sensitiveness8 #fg4 ,,the ,,retina constitutes the third and inner coat of the globe of the eye4 ,this1 the important part of the eye that is sensitive to light1 is a kind of nervous membrane1 formed by the expansion of the ultimate filaments of the optic nerve4 ,its texture is soft1 smooth1 and very thin2 it is translucent and of an opaline1 or grayish-white color4 ,it is sensitive to light alone2 and if any form of mechanical irritation be applied to it1 the sensations of touch and pain are not experienced1 but flashes of fire1 sparks1 and other luminous appearances are perceived4 ,thus an electric shock given to the eye-ball occasions a flash of light2 and a sudden fall1 or a blow upon the eye1 is often apparently accompanied by the vision of stars4 ,sidenote3 #fh4 ,specific energy of the optic nerve8 ,trial in ,germany8 #fh4 ,these phenomena are due to what is termed the #bjg specific energy of the optic nerve1 which nerve1 in common with the other nerves of special sense1 obeys a general law of nature1 which requires that1 whenever one of these nerves is stimulated1 it shall respond with the sensation peculiar to itself4 ,these flashes of retinal light have no power to illuminate external objects1 although the opposite of this statement has been maintained4 ,on the occasion of a remarkable trial in ,germany1 it was claimed by a person who had been severely assaulted on a very dark night1 that the flashes of light caused by repeated blows upon the head enabled him to see with sufficient distinctness to recognize his assailant4 ,but the evidence of scientific men entirely refuted this claim1 by pronouncing that the eye1 under the circumstances named1 was incapacitated for vision4 ,too intense light occasions a feeling of pain1 but it is of a peculiar kind1 and is termed dazzling4 ,illustration3 ,,fig4 #di4 ,sidenote3 #fi4 ,sensitiveness of all parts of the retina8 ,experiment to prove the existence of the blind spot4 #fi4 ,all parts of the retina are not equally sensitive1 and singularly enough1 the point of entry of the nerve of sight1 in the back part of the eyeball1 is entirely insensible to light1 and is called the blind spot4 ,the existence of this point may be proven by a simple experiment4 ,hold the accompanying figure1 on page #bjg1 directly in front of and parallel with the eyes4 ,close the left eye1 and fix the sight steadily on the left-hand circle2 then1 by gradually varying the distance of the figure from the eye1 at a certain distance 7about six inches71 the right-hand circle will disappear1 #bjh but nearer or further than that1 it will be plainly seen4 ,the other eye may be also tried1 with a similar result3 if the gaze be directed to the right-hand circle1 the left one will seem to disappear4 ,the experiment may be repeated by using two black buttons on the marble top of a bureau1 or on some other white surface4 ,the blind spot does not practically interfere with vision1 since the eye is seldom fixed immovably on an object1 and the insensitive parts of the two eyes can never be directed upon the same object at the same time4 ,sidenote3 #gj4 ,duration of impressions upon the retina8 ,how illustrated8 #gj4 ,impressions made upon the retina are not at once lost1 but persist a measurable length of time1 and then gradually fade away4 ,thus1 a bright light or color1 gazed at intently1 cannot be immediately dismissed from sight by closing or turning away the eyes4 ,a stick lighted at one end1 if whirled around rapidly in the dark1 presents the appearance of an unbroken luminous ring2 and the spokes of a rapidly revolving carriage-wheel seem to be merged into a plane surface4 ,if an object move too rapidly to produce this sort of lasting impression1 it is invisible1 as in the case of a cannon-ball passing through the air in front of us4 ,sidenote3 #ga4 ,what further illustration8 ,winking1 why it is not noticed4 ,ease with which the retina is fatigued or deprived of sensibility8 ,how shown8 #ga4 ,if a card1 painted with two primary colors--as red and yellow--be made to rotate swiftly1 the eye perceives neither of them distinctly2 but the card appears painted with their secondary color--orange4 ,the average duration of retinal images is estimated at one-eighth of a second2 and it is because they thus endure1 that the act of winking1 which takes place so frequently1 but so quickly1 is not noticed and does not interrupt the vision4 ,the retina is easily fatigued or deprived of its sensibility4 ,after looking steadfastly at a bright light1 or at a white object on a black ground1 a dark spot1 corresponding in shape to the bright object1 #bji presents itself in whatever direction we look4 ,this spot passes away as the retina resumes its activity4 ,sidenote3 #gb4 ,how further shown8 ,how is the result accounted for8 ,color-blindness8 #gb4 ,if a bright color be gazed at intently1 and the eyes then be turned to a white surface1 a spot will appear2 but its color will be the complement of that of the object4 ,fix the eye upon a red wafer upon a white ground1 and on removing the wafer a greenish spot of the same shape takes its place4 ,this result happens because a certain portion of the retina has exhausted its power to perceive the red ray1 and perceives only its complementary ray1 which is green4 ,the color thus substituted by the exhausted retina is called a physiological or accidental color4 ,in some persons the retina is incapable of distinguishing different colors1 when they are said to be affected with color-blindness4 ,thus1 red and green may appear alike1 and then a cherry-tree1 full of ripe fruit1 will seem of the same color in every part4 ,railroad accidents have occurred because the engineer of the train1 who was color-blind1 has mistaken the color of a signal4 ,sidenote3 #gc4 ,the location of the crystalline lens8 ,how supported8 ,its color and texture8 ,shape8 ,size8 #gc4 ,,the ,,crystalline ,,lens4--,across the front of the eye1 just behind the iris1 is situated the ,crystalline lens1 enclosed within its own capsule4 ,it is supported in its place partly by a delicate circular ligament1 and partly by the pressure of adjacent structures4 ,it is colorless and perfectly transparent1 and has a firm but elastic texture4 ,in shape it is doubly convex1 and may be rudely compared to a small lemon-drop4 ,the front face of the lens is flatter than the other1 and is in contact with the iris near its pupillary margin1 as is represented in the diagram on page #bad4 ,it is only one-fourth of an inch thick4 ,sidenote3 #gd4 ,cataract8 ,aqueous humor8 ,vitreous humor8 #gd4 ,when this little body becomes opaque1 and no longer affords free passage to the rays of light1 as often happens #baj with the advance of age1 an affection termed cataract is produced4 ,between the crystalline lens and the cornea is a small space which contains the aqueous humor 7see ,fig4 #dh1 ,a74 ,this humor consists of five or six drops of a clear1 colorless liquid very much like water1 as its name implies4 ,that part of the globe of the eye lying behind the lens is occupied by the vitreous humor1 so called from its fancied resemblance to melted glass 7,fig4 #dh1 ,v74 ,this humor is a transparent1 jelly-like mass1 enclosed within an exceedingly thin membrane4 ,it lies very closely applied to the retina1 or nervous membrane of the eye1 and constitutes fully two-thirds of the bulk of the eyeball4 ,illustration3 ,,fig4 #ej4--,,the ,,retinal ,,image4 ,sidenote3 #ge4 ,what is a lens and its focus8 ,the miniature image1 how produced8 #ge4 ,,the ,,uses ,,of ,,the ,,crystalline ,,lens4--,a convex lens has the property of converging the rays of light which pass through it2 and the point at which it causes them to meet is termed its focus4 ,if a lens of this description1 such as a magnifying or burning-glass1 be held in front of an open window1 in such a position as to allow its focus to fall upon a piece of paper1 it will be found to depict upon the paper a miniature image of the scene outside of the window4 ,it will be further noticed that the image is inverted1 or upside down1 and that the paper #baa at the place upon which the image is thrown is much brighter than any other part4 ,sidenote3 #gf4 ,how are figures painted upon the retina8 ,how proved8 #gf4 ,now all the transparent structures of the eye1 but especially the crystalline lens1 operate upon its posterior part1 or retina1 as the convex lens acts upon the paper2 that is1 they paint upon the retina a bright inverted miniature of the objects that appear in front of the eye 7,fig4 #ej74 ,that this actually takes place may be proved by experiment4 ,if the eyeball of a white rabbit1 the walls of which are transparent1 be examined while a lighted candle is held before the cornea1 an image of the candle-flame may be seen upon the retina4 ,sidenote3 #gg4 ,what can be said in respect to the form and structure of the crystalline lens8 #gg4 ,the form and structure of the crystalline lens endow it with a remarkable degree of refractive power1 and enable it to converge all the rays of light that enter it through the pupil1 to a focus exactly at the surface of the retina4 ,when this lens is removed from the eye1 as is frequently done for the cure of cataract1 it is found that the rays of light then have their focus three-eighths of an inch behind the retina2 that the image is four times larger than in the healthy eye1 that it is less brilliant1 and that its outline is very indistinct4 ,from this we learn that one of the uses of the crystalline lens is to make the retinal image bright and sharply-defined1 at the same time that it reduces its size4 ,indeed1 the small size of the image is a great advantage1 as it enables the limited surface of the retina to receive1 at a glance1 impressions from a considerable field of vision4 ,sidenote3 #gh4 ,how is the inverted image upon the retina presented in its true position to the mind8 #gh4 ,as the image upon the retina is inverted1 how does the mind perceive the object in its true1 erect position8 ,many explanations have been advanced1 but the simplest and most satisfactory appears to be found in the fact that #bab the retina observes no difference1 so to speak1 between the right and left or the upper and lower positions of objects4 ,in fact1 the mind is never conscious of the formation of a retinal image1 and until instructed1 has no knowledge that it exists4 ,consequently1 our knowledge of the relative location of external objects must be obtained from some other source than the retina4 ,the probable source of this knowledge is the habitual comparison of those objects with the position of our own bodies3 thus1 to see an elevated object1 we know we must raise the head and eyes2 and to see one at our right hand1 we must turn the head and eyes to the right4 ,illustration3 ,,fig4 #ea4--,,the ,,different ,,shapes ,,of ,,the ,,globe ,,of ,,the ,,eye4 ,n1 ,the ,natural ,eye4 ,m1 ,the ,short-sighted ,eye4 ,h1 ,the ,long-sighted ,eye4 ,s1 ,parallel ,rays from the ,sun4 ,sidenote3 #gi4 ,the uniform perfection of the eye8 ,examples8 ,the most common imperfection8 #gi4 ,,long-,,sight ,,or ,,hyperopia1 ,,and ,,short-,,sight ,,or ,,myopia4--,the eye is not in all cases perfectly formed4 ,for example1 persons may from birth have the cornea too prominent or too flat1 or the lens may be too thick or too thin4 ,in either of these conditions sight will be more or less defective from the first1 and the defect will not tend to disappear as life advances4 ,the most common imperfection1 however1 is in the shape of the globe2 which may be short 7,fig4 #ea1 ,h71 as compared with the natural eye1 ,n1 or it may be too long1 ,m4 ,sidenote3 #hj4 ,how is long-sight explained8 ,short-sight8 #hj4 ,when the globe is short1 objects can only be clearly #bac seen that are at a distance1 and the condition of the vision is known as long-sight1 or hyperopia4 ,it will be observed1 by reference to ,fig4 #ea1 that the focus of the rays of light would fall behind the retina of this eye4 ,when the globe is too long1 objects can only be clearly seen that are very near to the eye2 and the condition resulting from this defect is termed short-sight1 or myopia4 ,the focus of the rays of light is1 in this case1 formed in the interior of the eye in front of the retina4 ,sidenote3 #ha4 ,long-sight1 how common8 ,with what must it not be confounded8 ,kind of glasses for short-sight8 ,why8 ,squint8 #ha4 ,long-sight1 or hyperopia1 is common among schoolchildren1 nearly as much so as short-sight1 and must not be confounded with the defect known as the far sight of old people2 although in both affections the sight is improved by the use of convex glasses4 ,children not infrequently discover that they see much better when they chance to put on the spectacles of old persons4 ,for the relief of short-sight1 concave glasses should be employed2 as they so scatter the rays of light as to bring the focus to the retina1 and thus cause the vision of remote objects to become at once distinct4 ,that form of squint1 in which the eyes are turned inward1 is generally dependent upon long-sight1 while that rarer form1 when they turn outward1 is due to short-sight4 ,sidenote3 #hb4 ,what is stated in connection with the opera-glass8 ,experiment with pencil and distant object8 #hb4 ,,the ,,function ,,of ,,accommodation4--,if1 after looking through an opera-glass at a very distant object1 it is desired to view another nearer at hand1 it will be found impossible to obtain a clear vision of the second object unless the adjustment of the instrument is altered2 which is effected by means of the screw4 ,if an object1 like the end of a pencil1 be held near the eye1 in a line with another object at the other side of the room1 or out of the window1 and the eye be fixed first upon one and then upon the other1 it will be found that when the pencil is clearly seen1 the #bad further object is indistinct2 and when the latter is seen clearly1 the pencil appears indistinct2 and that it is impossible to see both clearly at the same time4 ,accordingly1 the eye must have the capacity of adjusting itself to distances1 which is in some manner comparable to the action of the screw of the opera-glass4 ,illustration3 ,,fig4 #eb4--,,the ,,function ,,of ,,accommodation4 ,the right half of the diagram shows the eye at rest4 ,the left half shows the lens accommodated for near vision4 ,sidenote3 #hc4 ,function of accommodation8 ,in what does it consist8 ,how is the function explained8 #hc4 ,this1 which has been called the function of accommodation1 is one of the most admirable of all the powers of the eye1 and is exercised by the crystalline lens4 ,it consists essentially in a change in the curvature of the front surface of the lens1 partly through its own elasticity1 and partly through the action of the ciliary muscle4 ,when the eye is at rest1 that is1 when accommodated for a distant object1 the lens is flatter and its curvature diminished 7see ,fig4 #eb72 but when strongly accommodated for near vision the lens becomes thicker1 its curvature increases1 and the image on the retina is made more sharp and distinct4 ,since a strong light is not required in viewing near objects1 the pupil contracts1 as is shown in the left-hand half of the diagram4 #bae ,sidenote3 #hd4 ,change of sight with the approach of old age8 ,explain the change8 #hd4 ,,old-,,sight1 ,,or ,,presbyopia4--,but this marvellously beautiful mechanism becomes worn with use2 or1 more strictly speaking1 the lens1 like other structures of the body1 becomes harder with the approach of old age4 ,the material composing the lens becomes less elastic1 the power to increase its curvature is gradually lost1 and as a consequence1 the person is obliged to hold the book further away when reading1 and to seek a stronger light4 ,in a word1 the function of accommodation begins to fail1 and is about the first evidence that marks the decline of life4 ,by looking at the last preceding diagram1 and remembering that the increased curvature of the lens cannot take place1 it will be at once understood why old-sight is benefitted in near vision by the convex lens1 such as the spectacles of old people contain4 ,it acts as a substitute for the deficiency of the crystalline lens4 ,sidenote3 #he4 ,hearing or audition8 ,what is sound8 ,how propagated commonly8 ,stone thrown in water8 #he4 ,,the ,,sense ,,of ,,hearing4--,,sound4--,hearing1 or audition1 is the special sense by means of which we are made acquainted with sound4 ,what is sound8 ,it is an impression made upon the organs of hearing1 by the vibrations of elastic bodies4 ,this impression is commonly propagated by means of the air1 which is thrown into delicate undulations1 in all directions from the vibrating substance4 ,when a stone is thrown into smooth water1 a wave of circular form is set in motion1 from the point where the stone struck1 which constantly increases in size and diminishes in force1 as it advances4 ,sidenote3 #hf4 ,sound-wave in the atmosphere8 ,its shape8 ,rate of motion8 ,sound1 in water1 air1 and solid bodies8 #hf4 ,somewhat resembling this1 is the undulation1 or sound-wave1 which is imparted by a sonorous vibration to the surrounding atmosphere4 ,its shape1 however1 is spherical1 rather than circular1 since it radiates upward1 downward1 and obliquely as well as horizontally1 like the wave #baf in water4 ,the rate of motion of this spherical wave of air is about #ajej feet per second1 or one mile in five seconds4 ,in water1 sound travels four times as fast as in air1 and still more rapidly through solid bodies2 along an iron rod1 its velocity is equal to two miles per second4 ,sidenote3 #hg4 ,the earth as a conductor of sound8 ,to what has the western ,indian been taught8 ,solid substances as conductors8 ,as regards sound1 in what respect is air necessary8 ,sound in a vacuum8 #hg4 ,the earth1 likewise1 is a good conductor of sound4 ,it is said that the ,indian of our western prairies can1 by listening at the surface of the ground1 hear the advance of a troop of cavalry1 while they are still out of sight1 and can even discriminate between their tread and that of a herd of buffaloes4 ,solid substances also convey sounds with greater power than air4 ,if the ear be pressed against one end of a long beam1 the scratching of a pin at the other extremity may be distinctly heard1 which will not be at all audible when the ear is removed from the beam4 ,although air is not the best medium for conveying sound1 it is necessary for its production4 ,sound cannot be produced in a vacuum1 as is shown by ringing a bell in the exhausted receiver of an air-pump1 for it is then entirely inaudible4 ,but let the air be readmitted gradually1 then the tones become more and more distinct1 and when the receiver is again full of air1 they will be as clear as usual4 #hh4 ,all sonorous bodies do not vibrate with the same degree of rapidity1 and upon this fact depends the pitch of the sounds that they respectively produce4 ,the more frequent the number of vibrations within a given time1 the higher will be the pitch2 and the fewer their number1 the lower or graver will it be4 ,now1 the rate of the successive vibrations of different notes has been measured1 and it has thus been found that if they are less than sixteen in a second1 no sound is audible2 while if they exceed #fj1jjj per second the sound is very faint1 and is painful to the #bag ear4 ,the extreme limit of the capacity of the human ear may be considered as included between these points2 but the sounds which we ordinarily hear are embraced between #ajj and #c1jjj vibrations per second4 #hi4 ,the ear1 which is the proper organ of hearing1 is the most complicated of all the structures that are employed in the reception of external impressions4 ,the parts of which it is composed are numerous1 and some of them are extremely small and delicate4 ,nearly all these parts are located in an irregularly shaped cavity hollowed out in the temporal1 or temple1 bone of each side of the head4 ,that part of the bone in which the auditory cavity is placed has the densest structure of all bones of the body1 and has therefore been called the petrous1 or rocky part of the temporal bone4 ,in studying the ear1 it is necessary to consider it as divided into three portions1 which are called1 from their relative positions1 the external ear1 the middle ear1 and the internal ear4 7,in the diagram1 ,fig4 #ec1 ,a1 the first is not shaded1 the second is lightly shaded1 and the last has a dark background47 ,sidenote3 #ij4 ,of what does the external portion of the organ of hearing consist8 ,describe the portal of that organ known as the ear4 ,its use8 #ij4 ,,the ,,external ,,ear4--,the external portion of the organ of hearing1 designated in ,fig4 #ec1 ,a1 includes1 first1 that outer part 7a71 which is commonly spoken of as the ear1 but which in fact is only the portal of that organ2 and1 secondly1 the auditory canal 7b74 ,the former consists of a flat flexible piece of cartilage1 projecting slightly from the side of the head1 attached to it by ligaments1 and supplied with a few weak muscles4 ,its surface is uneven1 and curiously curved1 and from its resemblance to a shell1 it has been called the concha4 ,it probably serves to collect sounds1 and to give them an inward direction2 although its removal is said not to impair the acuteness of hearing more than a few days4 #bah ,sidenote3 #ia4 ,the ear in the animals of delicate hearing8 ,rabbit8 ,fishes8 #ia4 ,in those animals whose hearing is more delicate than that of man1 the corresponding organ is of greater importance1 it being larger and supplied with muscles of greater power1 so that it serves as a natural kind of ear-trumpet1 which is easily movable in the direction of any sound that attracts the attention of the animal4 ,bold1 predaceous animals generally have the concavity of this organ directed forward1 while in timorous animals1 like the rabbit1 it is directed backward4 ,fishes have no outer ear1 but sounds are transmitted directly through the solid bones of the head1 to the internal organ of hearing4 ,illustration3 ,,fig4 #ec4--,,the ,,ear ,,and ,,its ,,different ,,parts4 ,a1 ,diagram of the ,ear4 a1 b1 ,external ,ear4 c1 ,membrane tympani4 d1 ,middle ,ear4 e1 ,internal ,ear4 ,b to ,b'''1 ,bones of the ,middle ,ear 7magnified74 ,c1 ,the ,labyrinths1 or ,internal ,ear 7highly magnified74 ,sidenote3 #ib4 ,what is the auditory canal8 ,describe it4 #ib4 ,the auditory canal 7,fig4 #ec1 ,a1 b71 which is continuous with the outer opening of the ear1 is a blind passage1 an inch and a quarter in length1 its inner extremity being bounded by a closely-fitting1 circular membrane4 ,this canal is of oval form1 is directed forward and inward1 #bai and is slightly curved2 so that the inner end is ordinarily concealed from view4 ,the pouch of the skin which lines this passage is smooth and thin1 especially at the lower end1 where it covers the membrane just mentioned4 ,sidenote3 #ic4 ,how is it guarded and protected8 ,ear-wax8 #ic4 ,as in the case of the nostrils1 a number of small1 stiff hairs garnish the margin of the auditory canal1 and guard it1 to some extent1 against the entrance of insects and other foreign objects4 ,the skin1 too1 covering its outer half1 is furnished with a belt of little glands which secrete a yellow1 viscid1 and bitter substance1 called ear-wax1 which is especially obnoxious to small insects4 ,as the outer layer of this wax-like material loses its useful properties1 it becomes dry1 and falls out of the ear in the form of minute1 thin scales1 a fresh supply being furnished from the little glands beneath4 ,in its form1 the auditory canal resembles the tube of an ear-trumpet1 and serves to convey the waves of sound to the middle portion of the ear4 ,sidenote3 #id4 ,what is the middle ear8 ,why called tympanum8 #id4 ,,the ,,middle ,,ear1 ,,or ,,tympanum4--,the middle ear is a small cavity1 or chamber1 of irregular shape1 about one-fourth of an inch across from side to side1 and half an inch long 7see ,fig4 #ec1 ,a1 d74 ,from the peculiar arrangement of its various parts it has very properly been called the tympanum1 or the drum of the ear4 ,the middle ear1 like the external canal1 contains air4 ,sidenote3 #ie4 ,what is the membrana tympani8 ,describe it4 #ie4 ,the circular membrane1 already mentioned as closing the auditory canal1 is the partition which separates the middle from the external ear1 and is called the membrana tympani 7c71 and may be considered as the outer head of the drum of the ear4 ,it is sometimes itself spoken of as the drum1 but this is incorrect2 since a drum is not a membrane1 but is the hollow space across which the membrane is stretched4 ,this membranous drum-head is very tense and elastic1 and so thin as to be almost transparent2 #bbj its margin is fastened into a circular groove in the adjacent bone4 ,each wave of sound that impinges against this delicate membrane causes it to vibrate1 and it1 in turn1 excites movements in the parts beyond4 ,sidenote3 #if4 ,what are the ossicles8 ,their number and names8 ,their arrangement8 #if4 ,within the tympanum is arranged a chain of remarkable little bones1 or ossicles4 ,they are chiefly three in number1 and from their peculiar shapes bear the following names3 malleus1 or the mallet2 incus1 or the anvil2 and stapes1 or the stirrup4 ,a fourth1 the smallest bone in the body1 in early life intervenes between the incus and stapes1 but at a later period it becomes a part of the incus4 ,it is called the orbicular bone4 ,small as are these ossicles--and they1 together1 weigh only a few grains--they have their little muscles1 cartilages1 and blood-vessels1 as perfectly arranged as the larger bones of the body4 ,one end of the chain of ossicles1 the mallet1 is attached to the membrane of the tympanum1 or outer drum-head1 while the other end1 the stirrup1 is firmly joined by its foot-piece to a membrane in the opposite side of the cavity4 ,the chain1 accordingly1 hangs suspended across the drum between the two membranes2 and when the outer one vibrates under the influence of the sound-wave1 the chain swings inward and transmits the vibration to the entrance of the inner ear4 ,sidenote3 #ig4 ,the ,eustachian tube8 ,describe it1 and state its use4 #ig4 ,the musical instrument1 the drum1 is not complete if the air within be perfectly confined3 we therefore find in all instruments of this kind a small opening in the side1 through which air may pass freely4 ,by this means the pressure of the air upon the vellum which forms the head of the drum is made equal upon all sides1 and the resonance of the drum remains unaffected by the varying density of the atmosphere4 ,it will1 therefore1 emit its proper sound1 whether it be struck in the rarified air of the mountain-top1 or in the condensed air of a mine4 ,the tympanum1 #bba or drum of the ear1 in like manner has an opening by means of which it communicates freely with the external air4 ,this opening is a narrow canal1 about an inch and a half long1 called the ,eustachian tube1 after the name of its discoverer1 ,eustachius4 ,illustration3 ,,fig4 #ed4--,,section ,,of ,,the ,,right ,,ear4 ,a1 ,the ,concha4 ,b1 ,auditory ,canal4 ,c1 ,membrane of the ,drum1 7the lower half47 ,d1 ,a small muscle4 ,e1 ,incus1 or ,anvil4 ,m1 ,malleus1 or ,mallet4 ,i1 ,eustachian ,tube4 ,g1 ,semicircular ,canals4 ,h1 ,cochlea1 or snail's shell4 ,sidenote3 #ih4 ,what can you state of the action of the ,eustachian tube8 #ih4 ,the course of this passage is indicated in ,fig4 #ed1 ,i1 directed downward and inward3 its other extremity opens into the upper part of the throat4 ,the passage itself is ordinarily closed1 but whenever the act of swallowing or gaping takes place1 the orifice in the throat is stretched open1 and the air of the cavity of the tympanum may then be renewed4 ,air may at will be made to enter through this tube1 by closing the mouth and nose1 and then trying #bbb to force air through the latter4 ,when this is done1 a distinct crackle or clicking sound is perceived1 due to the movement of the membranes1 and of the little bones of the ear4 ,sidenote3 #ii4 ,what other purpose does the ,eustachian tube serve8 ,how is this shown8 ,throat-deafness8 ,primary use of the ,eustachian tube8 #ii4 ,the ,eustachian tube serves1 also1 as an escape-pipe for the fluids which form within the middle ear2 and hence1 when its lining membrane becomes thickened1 in consequence of a cold1 or sore throat1 and the passage is thus more or less choked up1 the fluids are unable to escape as usual1 and therefore accumulate within the ear4 ,when this takes place1 the vibrations of the membrane are interfered with2 the sounds heard appear muffled and indistinct2 and a temporary difficulty of hearing1 which is known as throat-deafness1 is the result4 ,this result resembles the effect produced by interrupting the vibrations of a sonorous body1 such as all are familiar with2 if the finger be placed upon a piano-string or bell when it is struck1 the proper sound is no longer fully and clearly emitted4 ,but the primary use of this tube is to afford a free communication between the middle ear and the external atmosphere1 and thus secure an equal pressure upon both sides of the membrane of the drum of the ear1 however the density of the atmosphere may vary4 ,if1 from undue tension of the membranes1 pain is experienced in the ears1 when ascending into a rare atmosphere1 as in a balloon1 or descending into a dense one1 as in a diving-bell1 it may be relieved by repeating the act of swallowing1 from time to time1 in order that the inner and outer pressure may thus be promptly equalized4 ,sidenote3 #ajj4 ,the essential part of the organ of hearing8 ,its location8 ,formation8 #ajj4 ,,the ,,internal ,,ear1 ,,or ,,labyrinth4--,the most essential part of the organ of hearing is the distribution of the auditory nerve4 ,this is found within the cavity of the internal ear1 which1 from its exceedingly tortuous shape1 #bbc has been termed the labyrinth 7see ,fig4 #ec1 ,c74 ,this cavity is hollowed out in dense bone1 and consists of three parts2 the vestibule 7a71 or ante-chamber1 which is connected with the other two2 the cochlea 7b71 or snail's shell2 and the three semicircular canals 7c74 ,the manner in which the nerve of hearing is distributed is remarkable1 and is peculiar to this nerve4 ,in the vestibule and the canals its fibres are spread out over the inner surface1 not of the bony cavity but of a membranous bag1 which conforms to and partially fills that cavity2 and which floats in it1 being both filled and surrounded with a clear1 limpid fluid4 ,sidenote3 #aja4 ,where is the ear-sand found8 ,give the theory as to its use4 #aja4 ,a singular addition to the mechanism of hearing is observed within this membranous bag of the labyrinth4 ,this consists of two small oval ear-stones1 and a quantity of fine powder of a calcareous nature1 which is called ear-sand4 ,when examined under the microscope1 these sandy particles are seen to lie scattered upon and among the delicate filaments of the auditory nerve2 and it is probable1 that as the tremulous sound-wave traverses the fluid of the vestibule1 the sand rises and falls upon the nerve filaments1 and thus intensifies the sonorous impression4 ,sidenote3 #ajb4 ,in the cochlea or snail's shell8 ,key-board in the internal ear8 ,the vestibules8 ,semicircular canals8 #ajb4 ,in the cochlea1 or snail's shell1 which contains the fluid1 but no membrane1 the nerve ramifies upon a spiral shelf1 which1 like the cochlea itself1 takes two and a half turns1 growing continuously smaller as it winds upward4 ,as many as three thousand nerve fibres of different lengths have been counted therein2 which1 it has been thought1 form the grand1 yet minutely small key-board1 upon which strike all the musical tones that are destined to be conveyed to the brain4 ,the vestibule1 it is also supposed1 takes cognizance of noise as distinguished from musical sounds2 while the office of the semicircular canals is1 in part at least1 to prevent internal echoes1 or reverberations4 #bbd ,sidenote3 #ajc4 ,with what does the vestibule communicate8 ,what is the theory by which sound is conducted to the brain8 #ajc4 ,the vestibule communicates with the chain of bones of the middle ear by means of a small opening1 called the oval window1 or fenestra ovalis4 ,across this window is stretched the membrane1 which has already been alluded to as being joined to the stirrup-bone of the middle ear4 ,through this window1 then1 the sound-wave1 which traverses the external and middle ear1 arrives at last at the labyrinth4 ,the limpid fluid which the latter contains1 and which bathes the terminal fibres of the nerve of hearing1 is thus agitated1 the nerve-fibres are excited1 and a sonorous impression is conducted to the brain1 or1 as we say1 a sound is heard4 ,sidenote3 #ajd4 ,the formation of the organ of hearing with a view to its protection8 #ajd4 ,,protection ,,of ,,the ,,sense ,,of ,,hearing4--,from what has been seen of the complicated parts which compose the organ of hearing1 it is evident that while many of them possess an exquisite delicacy of structure1 ,nature has well and amply provided for their protection4 ,we have observed the concealed situation of the most important parts of the mechanism of the ear1 the length of its cavity1 its partitions1 the hardness of its walls1 and its communication with the atmosphere2 all these provisions rendering unnecessary any supervision or care on our part in reference to the interior of the ear4 ,but in respect to its external parts1 which are under our control and within the reach of harm1 it is otherwise4 ,we may both observe the dangers which threaten them1 and learn the means necessary to protect them4 ,sidenote3 #aje4 ,danger to which the hearing may be subjected8 ,advice8 #aje4 ,one source of danger to the hearing consists in lowering the temperature of the ear1 especially by the introduction of cold water into the auditory canal4 ,every one is familiar with the unpleasant sensation of distension and the confusion of sounds which accompany the filling of the ear with water when bathing3 the weight of the #bbe water within it really distends the membrane1 and the cold chills the adjacent sensitive parts4 ,it is not surprising1 therefore1 that the frequent introduction of cold water and its continued presence in the ear enfeeble the sense of hearing4 ,care should be taken to remove water from the ear after bathing1 by holding the head on one side1 and1 at the same time1 slightly expanding the outer orifice1 so that the fluid may run out4 ,for a like reason1 the hair about the ears should not be allowed to remain wet1 but should be thoroughly dried as soon as possible4 ,sidenote3 #ajf4 ,the general rule as to the use of water for the ear8 #ajf4 ,it may be stated as a general rule1 to which there are but few exceptions1 that no cold liquid should ever be allowed to enter the ear4 ,when a wash or injection is rendered necessary1 it should always be warmed before use4 ,the introduction of cold air is likewise hurtful1 especially when it pours through a crevice directly into the ear1 as it may often do through the broken or partially closed window of a car4 ,the avoidance of this evil gives rise to another almost as great2 namely1 the introduction of cotton or other soft substances into the ear to prevent it from catching cold4 ,this kind of protection tends to make the part unnaturally susceptible to changes of temperature1 and its security seems to demand the continued presence of the warm covering4 ,as a consequence of its presence1 sounds are not naturally conveyed1 and the sensitiveness of the nerve of hearing is gradually impaired4 ,sidenote3 #ajg4 ,chief source of injury to the ear8 ,directions for removing foreign objects from the ear8 ,of a live insect8 #ajg4 ,the chief source of injury1 however1 to the ear is from the introduction of solid substances into the auditory canal1 with the design of removing insects or other foreign objects that have found their way into the ear2 or with the design of scraping out the ear-wax4 ,for displacing a foreign object1 it is usually sufficient to syringe the ear gently with warm water1 the head being so held that the #bbf fluid easily escapes4 ,if a live insect has gained entrance to the ear1 it may first be suffocated by pouring a little oil upon it1 and afterward removed by syringing the ear as just mentioned4 #ajh4 ,the removal of ear-wax is generally unnecessary2 for1 as we have before seen1 ,nature provides that the excess of it shall become dry1 and then spontaneously fall out in the form of fine scales4 ,the danger from the introduction of solid implements into the outer ear is chiefly found in the fact that the membrane which lies at the bottom of it is very fragile1 and that any injury of it is liable to be permanent1 and to permanently impair the hearing of the injured ear4 ,,questions ,,for ,,topical ,,review4 ,give as full statements as you can on the following subjects3 #a4 ,production of sensation #agg1 #agh #b4 ,variety of sensations #agh1 #agi #c4 ,general sensibility #agi1 #ahj #d4 ,the sensation of pain #ahj #e4 ,the uses of pain #ahj1 #aha1 #ahb #f4 ,special sensation #ahb1 #ahc #g4 ,organs of touch #ahc1 #ahd #h4 ,the sense of touch #ahd1 #ahe1 #ahf #i4 ,the delicacy of touch #ahf1 #ahg #aj4 ,sensations of temperature and weight #ahg1 #ahh #aa4 ,the organ of taste #ahh1 #ahi #ab4 ,the sense of taste #ahi1 #aij #ac4 ,relations of taste1 etc4 #aij1 #aia #ad4 ,influence of education1 etc4 #aia1 #aib #ae4 ,the sense of smell #aib1 #aic #af4 ,the nerve of smell #aic1 #aid #ag4 ,uses of the sense of smell #aid1 #aie #ah4 ,the sense of sight #aif1 #aig #ai4 ,light1 and the optic nerve #aig1 #aih #bj4 ,the organ of sight #aih1 #aii #ba4 ,the orbits #aii #bb4 ,the eyelids #bjj1 #bja #bc4 ,the lachrymal fluid #bja1 #bjb1 #bjc #bd4 ,the eyeball #bjc1 #bjd #be4 ,the iris #bje1 #bjf #bf4 ,the retina #bjf1 #bjg1 #bjh1 #bji #bg4 ,the crystalline lens #bji1 #baj #bh4 ,uses of the lens #baj1 #baa1 #bab #bi4 ,long and short sight #bab1 #bac #cj4 ,function of accommodation #bac1 #bad #ca4 ,old sight1 or presbyopia #bae #cb4 ,hearing and sound #bae1 #baf1 #bag #cc4 ,the external ear #bag1 #bah1 #bai #cd4 ,the middle ear #bai-bbb #ce4 ,the internal ear #bbb1 #bbc1 #bbd #cf4 ,protection of the sense of hearing #bbd1 #bbe1 #bbf 99 99 99 99 99 #bbg ,,chapter ,,xi4 ,,the ,,voice4 ,voice and ,speech--,the ,larynx1 or the ,organ of the ,voice--,the ,vocal ,cords--,the ,laryngoscope--,the ,production of the ,voice--,the ,use of the ,tongue--,the different ,varieties of ,voice--,the ,change of ,voice--,its ,compass--,purity of ,tone--,ventriloquy4 ,sidenote3 #a4 ,the uttering of sounds by animals8 ,how produced8 #a4 ,,voice ,,and ,,speech4--,in common with the majority of the nobler animals1 man possesses the power of uttering sounds1 which are employed as a means of communication and expression4 ,in man1 these sounds constitute the voice2 in the animals1 they are designated as the cry4 ,the song of the bird is a modification of its cry1 which is rendered possible from the fact that its respiratory function is remarkably active4 ,the sounds of the animals are generally1 but not always1 produced by means of their breathing organs4 ,among the insects1 they are sometimes produced by the extremely rapid vibrations of the wings in the act of flight1 as in the case of the musquito2 or they are produced by the rubbing together of hard portions of the external covering of the body1 as in the cricket4 ,almost all kinds of marine animals are voiceless4 ,the tambour-fish and a few others have1 however1 the power of making a sort of noise in the water4 ,sidenote3 #b4 ,the evidence of man's superior endowment8 ,what is stated of the idiot8 ,parrot8 ,raven8 #b4 ,but man alone possesses the faculty of speech1 or the power to use articulate sounds in the expression of ideas1 and in the communication of mind with mind4 ,speech is thus an evidence of the superior endowment of man1 and involves the culture of the intellect4 ,an idiot1 while he #bbh may have complete vocal organs and full power of uttering sounds or cries1 is entirely incapable of speech2 and1 as a rule1 the excellence of the language of any people will be found to be proportional to their development of brain4 ,man1 however1 is not the only being that has the power to form articulate sounds1 for the parrot and the raven may also be taught to speak by rote2 but man alone attaches meaning to the words and phrases he employs4 ,sidenote3 #c4 ,speech and hearing8 ,a deaf child8 ,person having no ear for music8 ,impaired hearing8 ,what do the examples show8 #c4 ,speech is intimately related to the sense of hearing4 ,a child born deaf is1 of necessity1 dumb also2 not because the organs of speech are imperfect1 for he can utter cries and may be taught to speak1 and even to converse in a rude and harsh kind of language2 but because he can form no accurate notion of sound4 ,and a person1 whose hearing is not delicate1 or as it is commonly expressed1 who has no ear for music1 cannot sing correctly4 ,a person who has impaired hearing commonly talks in an unnaturally loud and monotonous voice4 ,these examples show the necessary relation of intelligence and the sense of hearing with that form of articulate voice1 which is termed speech4 ,sidenote3 #d4 ,organ of the voice8 ,where situated8 ,of what is its framework composed8 #d4 ,,the ,,organ ,,of ,,the ,,voice4--,the essential organ of the voice is the ,larynx4 ,this has been previously alluded to in its relation to the function of respiration2 and1 in the chapter on that subject1 are figured the front view of that organ 7,fig4 #ce71 and its connection with the trachea1 tongue1 and other neighboring parts 7,fig4 #ch74 ,it is situated at the upper part of the neck1 at the top of the trachea1 or tube by which air passes into and out of the lungs4 ,the framework of the larynx is composed of four cartilages1 which render it at once very strong and sufficiently flexible to enable it to move according to the requirements of the voice4 #bbi ,illustration3 ,,fig4 #ee4 ,,section ,,of ,,the ,,larynx ,,and ,,trachea4 ,a1 ,the ,epiglottis4 ,b1 ,the ,thyroid ,cartilage4 ,c1 ,arytenoid ,cartilage4 ,d1 ,ventricle of the ,larynx4 ,e1 ,cricoid ,cartilage4 ,f1 ,right ,vocal ,cord4 ,h1 ,the ,trachea4 ,sidenote3 #e4 ,names1 formation1 and situation of the cartilages8 #e4 ,the names of the cartilages are 7#a7 the thyroid1 which is a broad thin plate1 bent in the middle and placed in the central line of the front part of the neck1 where it is known as the pomum ,adami1 or ,adam's apple 7,fig4 #ee1 ,b71 and where it may be felt moving up and down with each act of swallowing2 7#b7 the cricoid1 which is shaped like a seal ring1 with the broad part placed posteriorly 7,fig4 #ee1 ,e74 ,at the top of the cricoid cartilage are situated the two small arytenoid cartilages1 the right one of which is shown in ,fig4 #ee1 ,c4 ,these latter little organs are much more movable than the other two1 and are very important in the production of the voice4 ,they have a true ball and socket joint1 and several small muscles which contract and relax with as perfect regularity and accuracy as any of the larger muscles of the body4 ,sidenote3 #f4 ,lining of the interior of the larynx8 ,the epiglottis8 #f4 ,the interior of the larynx is lined with a very sensitive mucous membrane1 which is much more closely adherent to the parts beneath than is usually the case with membranes of this description4 ,the epiglottis 7,a71 consisting of a single leaf-shaped piece of cartilage1 is attached to the front part of the larynx4 ,it is elastic1 easily moved1 and fits accurately over the entrance to the air-passages below it4 ,its office is to guard these delicate passages and the lungs against the intrusion of food and other foreign #bcj articles1 when the act of swallowing takes place4 ,it also assists in modifying the voice4 ,sidenote3 #g4 ,where are the vocal cords8 ,the false cords8 ,the true cords8 #g4 ,,the ,,vocal ,,cords4--,within the larynx1 and stretched across it from the thyroid cartilage in front to the arytenoid cartilages behind1 are placed the two sets of folds1 called the vocal cords4 ,the upper of these1 one on each side1 are the false cords1 which are comparatively fixed and inflexible4 ,these are not at all essential to the formation of vocal sounds1 for they have been injured1 in those lower animals whose larynx resembles that of man1 without materially affecting their characteristic cries4 ,below these1 one on each side1 are the true vocal cords 7,fig4 #ee1 ,f71 which pursue a similar direction to the false cords1 namely1 from before backward4 ,but they are composed of a highly elastic1 though strong tissue1 and are covered with a thin1 tightly-fitting layer of mucous membrane4 ,their edges are smooth and sharply defined1 and when they meet1 as they do in the formation of sounds1 they exactly match each other4 ,sidenote3 #h4 ,where is the ventricle of the larynx8 ,the essentials to the formation of the tones and modulation of the voice8 #h4 ,between the true and false vocal cords is a depression on each side1 which is termed the ventricle of the larynx 7,fig4 #ee1 ,d74 ,the integrity of these true cords1 and their free vibration1 are essential to the formation of the tones and the modulation of the natural voice4 ,this is shown by the fact that1 if one or both of these cords are injured or become diseased1 voice and speech are compromised2 or when the mucous membrane covering them becomes thickened1 in consequence of a cold1 the vocal sounds are rendered husky and indistinct4 ,when an opening is made in the throat below the cords1 as not infrequently happens in consequence of an attempt to commit suicide1 voice is impossible except when the opening is closed by external pressure4 #bca ,illustration3 ,,fig4 #ef4 ,a ,,view ,,of ,,the ,,vocal ,,cords ,,by ,,means ,,of ,,the ,,laryngoscope4 ,sidenote3 #i4 ,variation in the interval between the true cords of the voice8 ,experiment with the mirror8 #i4 ,the interval or space between the true cords of the voice is constantly varying1 not only when their vocal function is in exercise1 but also during the act of respiration4 ,every time the lungs are inflated1 the space increases to make wide the entrance for the air2 and diminishes slightly during expiration4 ,so that these little cords move gently to and fro in rhythm with the expansion and contraction of the chest in breathing4 ,these movements and others may be seen to take place1 if a small mirror attached to a long handle be placed back into the upper part of the throat2 the handle near the mirror must be bent at an angle of #de1 so that we may look around the corner1 so to speak1 behind the tongue4 ,the position which the mirror must assume will be understood by reference to ,fig4 #ch4 ,a view of what may be seen under favorable circumstances1 during tranquil inspiration is represented in ,fig4 #ef4 ,the vocal cords are there shown as narrow1 white bands1 on each side of the central opening1 and since the image is inverted1 the epiglottis appears uppermost4 ,the rings partly seen through the opening belong to the trachea4 ,this little mirror is the essential part #bcb of an instrument1 which is called the laryngoscope1 and1 simple as it may seem1 it is accounted one of the most valuable of the recently invented appliances of the medical art4 ,sidenote3 #aj4 ,the formation of true vocal tones8 #aj4 ,,the ,,production ,,of ,,the ,,voice4--,during ordinary tranquil breathing no sound is produced in the larynx1 true vocal tones being formed only during forcible expiration1 when1 by an effort of the will1 the cords are brought close together1 and are stretched so as to be very tense4 ,the space between them is then reduced to a narrow slit1 at times not more than #a_/ajj of an inch in width2 and the column of expired air being forced through it causes the cords to vibrate rapidly1 like the strings of a musical instrument4 ,thus the voice is produced in its many varieties of tone and pitch2 its intensity1 or loudness1 depending chiefly upon the power exerted in expelling the air from the lungs4 ,when the note is high1 the space is diminished both in length and width2 but when it is low1 the space is wider and longer 7,fig4 #eg1 ,b1 ,c71 and the number of vibrations is fewer within the same period of time4 ,illustration3 ,,fig4 #eg4 ,,the ,,different ,,positions ,,of ,,the ,,vocal ,,cords4 ,a1 ,the position during inspiration4 ,b1 ,in the formation of low notes4 ,c1 ,in the formation of high notes4 ,sidenote3 #aa4 ,to what is the personal quality of the voice mainly due8 ,what aids are there8 #aa4 ,the personal quality of the voice1 or that which enables us to recognize a person by his speech1 is mainly due to the peculiar shape of the throat1 nose1 and mouth1 and #bcc the resonance of the air contained within those cavities4 ,the walls of the chest and the trachea take part in the resonance of the voice1 the air within them vibrating at the same time with the parts above them4 ,this may be tested by touching the throat or breast-bone1 when a strong vocal effort is made4 ,the teeth and the lips also are important1 as is shown by the unnatural tones emitted by a person who has lost the former1 or by one who is affected with the deformity known as hare-lip4 ,the tongue is useful1 but not indispensable to speech2 the case of a woman is reported1 from whom nearly the whole tongue had been torn out1 but who could1 nevertheless1 speak distinctly and even sing4 ,sidenote3 #ab4 ,varieties of voice8 ,the baritone8 ,the voice in early youth8 #ab4 ,,the ,,varieties of voice are said to be four in number2 two1 the bass and tenor1 belonging to the male sex2 and two1 the contralto or alto1 and soprano1 peculiar to the female4 ,the baritone voice is the name given to a variety intervening between the bass and tenor4 ,in man1 the voice is strong and grave2 in woman1 soft and high4 ,in infancy and early youth1 the voice is the same in both sexes1 being of the soprano variety3 that of boys is both clear and loud1 and being susceptible of considerable training1 is highly prized in the choral services of the church and cathedral4 ,at about fourteen years of age the voice is said to change2 that is1 it becomes hoarse and unsteady by reason of the rapid growth of the larynx4 ,in the case of the girl1 the change is not very marked1 except that the voice becomes stronger and has a wider compass2 but in the boy1 the larynx nearly doubles its size in a single year1 the vocal cords grow thicker1 longer1 and coarser1 and the voice becomes masculine in character4 ,during the progress of this change1 the use of the voice in singing is injudicious4 ,sidenote3 #ac4 ,the range of the voice8 ,result of careful training of the vocal organs8 #ac4 ,the ordinary range of each of the four varieties of #bcd the voice is about two octaves2 but this is exceeded in the case of several celebrated vocalists4 ,madame ,parepa-,rosa has a compass of three full octaves4 ,when the vocal organs have been subjected to careful training1 and are brought under complete control of the will1 the tension of the cords become exact1 and their vibrations become exceedingly precise and true4 ,under these circumstances the voice is said to possess purity of tone1 and can be heard at a great distance1 and above a multitude of other sounds4 ,the power of a pure voice to make itself heard was recently exemplified in a striking manner3 at a musical festival held in an audience-room of extraordinary size1 and amid an orchestra of a thousand instruments and a chorus of twelve thousand voices1 the artist named above also sang2 yet such was the purity and strength of her voice that its notes could be clearly heard rising above the vast waves of sound produced by the full accompaniment of chorus and orchestra4 ,sidenote3 #ad4 ,the production of the articulate sounds8 ,what experiment is mentioned8 #ad4 ,in the production of the articulate sounds of speech1 the larynx is not directly concerned1 but those sounds really depend upon alterations in the shape of the air-passages above that organ4 ,that speech is not necessarily due to the action of the larynx is proven by the following simple experiment4 ,let an elastic tube be passed through the nostril to the back of the mouth4 ,then1 while the breath is held1 cause the tongue1 teeth1 and lips to go through the form of pronouncing words1 and at the same time1 let a second person blow through the tube into the mouth4 ,speech1 pure and simple1 or1 in other words1 a whisper is produced4 ,still further continue the experiment1 while permitting vocal sounds to be made1 and there will be produced a loud and whispering speech at the same moment2 thus showing that voice and speech are the result of two distinct acts4 ,sighing1 in like manner1 is #bce produced in the mouth and throat2 if1 however1 a vocal sound be added1 the sigh is changed into a groan4 ,sidenote3 #ae4 ,what is ventriloquism8 ,indication of the original meaning of the word8 ,how are the ventriloquous sounds produced8 #ae4 ,,ventriloquism is a peculiar modification of natural speech1 which consists in so managing the voice that words and sounds appear to issue1 not from the person1 but from some distant place1 as from the chimney1 cellar1 or the interior of a chest4 ,the original meaning of the word ventriloquism 7that is1 speaking from the belly71 indicates the early belief that this mode of speech was dependent upon the possession and use of some special organ besides the larynx and mouth2 but at the present time1 it is known that it is produced by these organs alone1 and that the sources of deception consist on the part of the performer1 in the dexterous management of the voice1 together with a talent for mimicry2 and1 on the part of the auditory1 in the liability of the sense of hearing to error in respect to the direction of sounds4 ,the ventriloquist not only seems to throw his voice1 as it is said1 or simulates the sound as it usually appears at a distance with but little motion of the lips and face1 but he imitates the voices of an infant and of a feeble old man1 of a drunken man disputing with an exasperated wife1 the broken language of a foreigner1 the cry of an animal in distress1 demonstrating that the performer must be proficient in the art of mimicry4 ,ventriloquism was known to the ancient ,romans and ,greeks2 and it is thought that the mysterious responses that were said to issue from the sacred trees and shrines of the oracles at ,dodona and ,delphi1 were really uttered by priests who had the power of producing this form of speech4 99 99 99 99 99 #bcf ,,chapter ,,xii4 ,,the ,,use ,,of ,,the ,,microscope ,,in ,,the ,,study ,,of ,,physiology4 ,sidenote3 #a4 ,the will of the ,creator1 by what obeyed8 ,the power of a muscle8 ,amount of duty performed by the liver8 #a4 ,,the ,,law ,,of ,,the ,,tissues4--,the will of an infinite ,creator is obeyed by atoms as well as by worlds4 ,he has seen fit to commit all the functions of life to structures or tissues so small as to be invisible to the naked eye4 ,a muscle1 for example1 as we have already learned1 is composed of innumerable filaments1 visible only by the aid of the microscope2 and the power of the muscular mass is but the sum of the contractile power of the filaments which enter into its composition4 ,again1 each cell of the liver1 invisible to unassisted sight1 is a secreting organ1 and the liver performs as much duty as the sum of these minute organs renders possible and no more4 ,sidenote3 #b4 ,necessity for using the microscope8 ,the advantages gained by its use8 #b4 ,,the ,,necessity ,,of ,,the ,,microscope4--,if1 therefore1 we would know the real structure of the human body1 we must make use of the microscope4 ,we are not at liberty either to use it or not2 we must have recourse to it in order to obtain a real knowledge of the human body4 ,our eyes are constructed for the common offices of life1 to provide for our wants and guard us from the ordinary sources of danger2 but by arming them with lenses1 the real structure of plants and animals is revealed to our intelligence2 and enemies1 otherwise invisible1 that lie in wait in the air we breathe1 and in our daily food and drink1 to destroy life1 are guarded against4 ,sidenote3 #c4 ,what are convex lenses8 ,kind of lenses used in microscopes8 ,experiment8 ,picture thrown upon the eye8 ,derivation of the word microscope8 #c4 ,,convex ,,lenses1 or magnifying glasses1 are disks of glass or other transparent substance1 which have the #bcg property of picturing upon the retina of the eye an image of an object larger than the image produced there without their aid4 ,the glasses used in microscopes are either double convex lenses 7a7 or plano-convex lenses 7b74 ,if a double convex lens or a plano-convex one be placed over a hole in the shutter of a darkened room1 or over the key-hole of a door1 and a piece of paper be held at a proper distance1 a picture of all objects in front of the lens will be thrown on the paper1 as in the camera-obscura or the magic-lantern4 ,now1 in the same manner1 a lens throws a picture of objects to which it is directed on the retina of the eye1 and when that picture is larger than the image made in the eye by the object1 without the aid of the lens1 it is magnified1 or the lens has served as a microscope1 so called1 from its use in seeing small objects1 from mikros1 small1 and skopeo1 to see4 ,illustration ,sidenote3 #d4 ,kinds of microscope8 ,what are simple microscopes8 #d4 ,,different ,,kinds ,,of ,,microscopes4--,microscopes are either simple or compound4 ,the glasses of magnifying spectacles1 like those commonly used by aged persons1 are simple microscopes4 ,magnifying glasses1 mounted in frames such as are for sale by opticians and others1 for the detection of counterfeit money1 are simple microscopes1 and are useful in studying the coarser structure of plants and animals4 ,sidenote3 #e4 ,construction of the most powerful simple microscopes8 ,in practice8 ,a doublet8 ,triplet8 ,why are compound microscopes superior to simple ones8 #e4 ,the most powerful simple microscopes are made by melting in a flame a thread of spun glass1 so as to form a #bch minute globule or bead1 which1 when set in a piece of metal and used to examine objects on a plate of glass held up to the light1 gives a high magnifying power4 ,in practice1 however1 it is found better to use several magnifying glasses of moderate power1 than a simple lens alone of high power4 ,a combination of two lenses is called a doublet--of three1 a triplet4 ,all simple microscopes throw an enlarged image of the object upon the retina4 ,compound microscopes are so constructed that the enlarged image of an object is again magnified by a second lens1 and hence their magnifying power is vastly superior to that of simple microscopes4 ,sidenote3 #f4 ,explain1 by means of the diagram1 the action of the compound microscope4 #f4 ,the accompanying diagrams will explain the action of the compound microscope compared with that of the simple microscope4 ,in ,fig4 #eh1 which represents the working of the simple microscope1 the rays from the object 7a b71 passing through the lens 7,l71 form an image 7a' b'7 in the retina of the eye 7,e71 and as all images are inverted in the eye1 the object is seen as all other objects are1 and appears erect4 ,in ,fig4 #ei is seen the action of the compound microscope4 ,an inverted image 7a' b'7 of the object 7a b7 is magnified by the second lens 7,l'71 and an erect image is thrown upon the retina1 which1 as all other objects seen erect with the naked eye are inverted1 gives to the image a contrary direction1 or inverts it to the mind4 ,illustration3 ,,fig4 #eh4--,,simple ,,microscope4 #bci ,sidenote3 #g4 ,portions1 in a compound microscope8 ,the glasses8 #g4 ,a ,,compound ,,microscope consists of two portions3 the optical portion1 or the lenses1 and the mechanical portion1 or the instrument which bears the lenses4 ,the glasses of a compound microscope are two3 the object-glass 7,d71 ,fig4 #fj1 and the lower lens of ,fig4 #ei1 and the ocular or eye-piece 7,a71 ,fig4 #fj1 and the upper piece of ,fig4 #ei4 ,both the object-glass and the eye-piece may1 and usually do1 consist of more than one lens1 for1 as previously mentioned1 better results are obtained by a combination of lenses of moderate power than by single lenses of high power and great curvature4 ,sidenote3 #h4 ,how to choose a microscope8 ,how to use it8 #h4 ,,how ,,to ,,choose ,,and ,,use ,a ,,microscope4--,no attractiveness in the mechanical part of a microscope can compensate for inferior lenses2 and the very first consideration in the choice of an instrument should be the excellence of the optical part of the instrument4 ,in the use of the instrument1 care should be exercised to keep the lenses clean1 free from dust1 not to press the object-glass upon the object under observation1 and not to wet it in the water in which most objects are examined4 ,a good microscope requires its own table2 and when not in use should be covered by a bell glass or a clean linen cloth4 ,illustration3 ,,fig4 #ei4 ,,compound ,,microscope4 #bdj ,illustration3 ,,fig4 #fj4 ,a1 ,eye-piece4 ,b1 ,body4 ,c1 ,collar4 ,d1 ,object-glass4 ,e1 ,stage4 ,f1 ,hinge4 ,g1 ,mirror4 ,h1 ,stand4 ,sidenote3 #i4 ,the characteristics of the best instrument8 ,what special requisites should be insisted upon8 ,why1 as to a horizontal stage8 #i4 ,the mechanical portion of the instrument varies greatly in different instruments4 ,that one is the best which is simplest1 the most solid and easily managed4 ,the stage 7,e71 upon which the object is placed1 should not be movable3 it should be solid and firm4 ,the screw by which the focal distance is adjusted1 and which #bda is in constant use1 should be so placed that it can be worked by the hand resting on the table3 otherwise fatigue is soon induced4 ,the direction of the tube carrying the glasses should be perpendicular1 and the stage therefore horizontal4 ,most objects in human anatomy are examined in water or in other liquids1 or they are themselves liquids2 hence an oblique stage is often inconvenient4 ,illustration3 ,,fig4 #fa4 #bdb ,sidenote3 #aj4 ,slides8 ,covers1 square and circular8 ,how kept8 #aj4 ,,additional ,,apparatus4--,as almost all objects in human anatomy are examined by transmitted light thrown up from the mirror 7,g1 ,fig4 #fj7 beneath the stage through the object to the eye1 they must be placed upon strips of clear glass about three inches long and one inch wide1 commonly called slides4 ,these should be procured with the microscope4 ,again1 most objects seen with high powers require to be covered with a thin plate of glass1 very properly called a cover1 that the moisture of the specimen may not tarnish the object-glass4 ,square or circular covers of very thin glass are therefore provided2 and a good supply of these should be always on hand4 ,these glasses should be kept in a covered dish filled with a mixture of alcohol and water4 ,simple water will not remove the fatty matter which exists in all animal tissues1 and1 therefore1 the glasses cannot be thoroughly cleaned with it alone4 ,sidenote3 #aa4 ,cleaning the glasses8 ,knives1 scissors1 etc48 ,various liquids8 #aa4 ,when glasses are required for use1 they should be removed from the liquid and wiped clean and dry with a soft linen handkerchief4 ,delicate knives1 scissors1 needles mounted in handles1 forceps1 pipettes or little tubes for taking up water1 should be obtained2 these are essential to all microscopical study4 ,the table should be supplied with glass-stoppered bottles containing the various liquids ordinarily used in the study of physiology4 ,thus1 tincture of iodine is indispensable in studying vegetable structure1 acetic acid in the study of animal tissues2 and other articles will have to be added from time to time1 as your progress in study demands them4 #bdc ,sidenote3 #ab4 ,bodies1 in air and water8 ,the examination of starch8 #ab4 ,,preliminary ,,studies4--,in order to prepare the way for the study of any department of science with the aid of the microscope--for the microscope is but an eye1 and can be turned in almost any direction for purposes of investigation--it is necessary to become acquainted with the many objects which are liable to complicate the examination of particular structures4 ,both air and water are full of floating bodies1 and the most common of these should first occupy the attention4 ,in the city1 particles of starch are always floating in the air4 ,take a very minute portion of wheat flour1 place it in the middle of a clean glass slide1 drop upon it a drop of pure water1 cover it with a plate of thin glass1 and examine it with a power of from one hundred to six hundred diameters4 ,it will be found to be composed of minute grains or granules1 the largest of which are made up of coats or layers1 like an onion1 arranged around a central spot called the hilum4 ,sidenote3 #ac4 ,the examination with solution of iodine8 ,advice respecting other articles8 #ac4 ,make another preparation in the same manner1 and1 after adding the water and before covering with the thin glass cover1 add a small drop of a solution of iodine4 ,now1 upon examining the specimen1 every grain will be seen to be of a beautiful deep blue color4 ,after thus studying wheat starch1 the starch of ,indian corn1 of arrowroot1 and of various grains should be examined in like manner1 and their resemblances and differences noted4 ,the granules of potato-starch are as distinctly marked as any4 7,see ,fig4 #ae1 page #fa47 ,sidenote3 #ad4 ,directions for examining cotton and other fibres8 ,vegetable hairs8 #ad4 ,fibres of cotton1 lint1 and wool are liable to be found in every specimen prepared for microscopical examination4 ,in order to study these1 any cotton1 woollen1 or linen fabric1 or garment1 may be scraped1 and the scrapings placed on a piece of glass moistened with water1 covered with the thin glass plate or cover as before1 and #bdd examined with the same magnifying power1 namely1 from one hundred to six hundred diameters4 ,vegetable hairs or down are constantly floating in air and water4 ,these are of very various forms1 are simple or grouped1 and form very interesting objects of study4 ,they are readily procured from the epidermis or outer membrane of the leaves or stems of plants1 by section with a delicate knife4 ,sidenote3 #ae4 ,directions for examining various tissues8 ,down of moths1 and other structures8 #ae4 ,the tissues of plants1 epidermis1 ducts1 and woody fibres are constantly found in microscopic preparations4 ,they may be studied in delicate sections made with a sharp knife1 or by tearing vegetable tissues apart with needles4 ,the down of moths1 the hairs of different animals1 the fibres of paper1 the most common animalcules in water1 the dust of shelves1 and generally the structures found in all vegetable and animal substances by which we are surrounded1 should be studied as a preliminary to any special line of microscopical investigation4 ,sidenote3 #af4 ,directions for examining a drop of blood8 #af4 ,,the ,,study ,,of ,,human ,,tissues4--,when this has been done and familiarity with the use of the instrument has been obtained1 proceed to the study of the human body1 for human physiology is our subject4 ,if the end of the finger be pricked with a pin1 a drop of blood may be procured for examination4 ,place this on one of the glass slides1 cover it with a thin piece of glass1 press down the cover so as to make a thin layer1 and then examine with the magnifying power just mentioned4 ,do not add water1 for that will cause the blood corpuscles to disappear4 ,if the drop of blood is placed under the microscope at once after being drawn from the finger1 most interesting phenomena will be observed4 ,the red corpuscles will be seen to arrange themselves in rows1 like piles of coin1 while the blood is coagulating4 ,the spherical1 white corpuscles will #bde be left out of the rows of red disks1 and1 if the highest power be used1 will be seen to change their shape constantly4 ,sidenote3 #ag4 ,examination of the scales of the mouth8 ,dandruff8 #ag4 ,if you scrape with a dull knife the inside of the cheek1 the flattened scales of pavement epithelium1 or of the insensible covering which1 analogous to the scarf-skin on the outer surface of the body1 lines the cavities of its interior1 may be readily studied4 ,they have the appearance of transparent tiles1 each enclosing a round or oval body1 called its nucleus4 ,dandruff and the scrapings from the skin of the body are composed of scales like those of the mouth1 but they differ somewhat in being hardened by horny matter1 and in having a very faint central body or nucleus4 ,sidenote3 #ah4 ,in what1 as respects the tissues1 do the warm blooded animals differ8 ,statement of ,milne ,edwards8 #ah4 ,,the ,,tissues ,,of ,,the ,,inferior ,,animals4--,the warm-blooded animals do not differ in the tissues1 or microscopic structures1 that compose them1 but only in the amount and arrangement of these tissues4 ,milne ,edwards says these tissues do not differ much in different animals1 but their mode of association varies2 and it is chiefly by reason of the differences in the combination of these associations in various degrees1 that each species possesses the anatomical properties and characters which are peculiar to it4 ,sidenote3 #ai4 ,how to procure materials for the study of the tissues of man8 #ai4 ,hence the butcher's stall will furnish all the materials for the study of the microscopic tissues4 ,the structure of the heart1 lungs1 liver1 brain1 and muscle may all be studied1 and well studied1 by using minute pieces of the flesh of the lower animals1 especially of the quadrupeds4 ,such portions of these animals as are not exposed for sale can be readily obtained by order from the slaughter-house4 ,to examine with the powers of which we have been speaking1 it is only necessary to cut off #bdf exceedingly small pieces1 tear them apart with needles1 or make very delicate sections with a sharp knife4 #bj4 ,,incentives ,,to ,,study4--,a complete knowledge of all minute structures is not to be expected at once1 for you are here introduced into a new realm of ,nature1 a world of little things as vast1 as wonderful1 and as carefully constructed as the starry firmament1--that other realm of grand objects which the astronomer nightly scans with the telescope4 ,it will not appear singular1 therefore1 if1 at first1 you feel strange and awkward in this new creation4 ,with a little perseverance1 however1 and with the attention directed toward simple objects at the outset1 it will not be long before an increasing experience will engender confidence4 #ba4 ,if to all this there be added an enthusiastic study of the standard authorities on the subject1 the rate of progress will be by so much the more rapid4 ,as compared with similar studies1 few possess more interest than microscopy1 and to the one who pursues it with fondness1 it constantly affords sources of pleasure and agreeable surprises2 and in the end1 often leads to new and valuable additions to the sum of human knowledge4 ,the depths which the microscope is employed to fathom are no more completely known1 than are the heights above us explored and comprehended by the astronomer4 ,,questions ,,for ,,topical ,,review4 ,state what you can on the following subjects3 #a4 ,voice and speech #bbg1 #bbh #b4 ,the organ of the voice #bbh1 #bbi #c4 ,the vocal cords #bcj1 #bca #d4 ,the production of the voice #bcb1 #bcc #e4 ,the varieties of voice #bcc1 #bcd #f4 ,ventriloquism #bce #g4 ,the law of the tissues #bcf #h4 ,necessity of the microscope #bcf #i4 ,convex lenses #bcf1 #bcg #aj4 ,kinds of microscope #bcg1 #bch #aa4 ,choosing a microscope #bci1 #bdb #ab4 ,preliminary studies #bdc1 #bdd #ac4 ,the study of human tissues #bdd #ad4 ,the study of the inferior animals #bde 99 99 99 99 99 #bdg ,,appendix4 ------o------ ,,poisons ,,and ,,their ,,antidotes4 ,accidents from poisoning are of such frequent occurrence1 that every one should be able to administer the more common antidotes1 until the services of a physician can be obtained4 ,as many poisons bear a close resemblance to articles in common use1 no dangerous substance should be brought into the household without having the word poison plainly written or printed on the label2 and any package1 box1 or vial1 without a label1 should be at once destroyed1 if the contents are not positively known4 ,when a healthy person is taken severely and suddenly ill soon after some substance has been swallowed1 we may suspect that he has been poisoned4 ,in all cases where poison has been taken into the stomach1 it should be quickly and thoroughly evacuated by some active emetic1 which can be speedily obtained4 ,this may be accomplished by drinking a tumblerful of warm water1 containing either a tablespoonful of powdered mustard or of common salt1 or two teaspoonfuls of powdered alum in two tablespoonfuls of syrup4 ,when vomiting has already taken place1 it should be maintained by copious draughts of warm water or mucilaginous drinks1 such as gum-water or flaxseed tea1 and tickling the throat with the finger until there is reason to believe that all the poisonous substance has been expelled from the stomach4 ,the following list embraces only the more common poisons1 together with such antidotes as are usually at hand1 to be used until the physician arrives4 ,,poisons4 ,,acids4--,hydrochloric acid2 muriatic acid 7spirits of salt72 nitric acid 7aqua fortis72 sulphuric acid 7oil of vitriol74 ,,antidote4--,an antidote should be given at once to neutralize the acid4 ,strong soapsuds is an efficient remedy1 and can always be obtained4 ,it should be followed by copious draughts of warm water or flaxseed tea4 ,chalk1 magnesia1 soda or saleratus 7with water7 or #bdh lime-water1 are the best remedies4 ,when sulphuric acid has been taken1 water should be given sparingly1 because1 when water unites with this acid1 intense heat is produced4 ,oxalic acid4 ,,antidote4--,oxalic acid resembles ,epsom salts in appearance1 and may easily be mistaken for it4 ,the antidotes are magnesia1 or chalk mixed with water4 ,,prussic ,,acid2 oil of bitter almonds2 laurel water2 cyanide of potassium 7used in electrotyping74 ,,antidote4--,cold douche to the spine4 ,chlorine water1 or water of ammonia largely diluted1 should be given1 and the vapor arising from them may be inhaled4 ,,alkalies ,,and ,,their ,,salts4--,,ammonia 7hartshorn71 liquor or water of ammonia4 ,,potassa3--caustic potash1 strong ley1 carbonate of potassa 7pearlash71 nitrate of potassa 7saltpetre74 ,,antidote4--,give the vegetable acids diluted1 as weak vinegar1 acetic1 citric1 or tartaric acids dissolved in water4 ,castor oil1 linseed oil1 and sweet oil may also be used2 they form soaps when mixed with the free alkalies1 which they thus render harmless4 ,the poisonous effects of saltpetre must be counteracted by taking mucilaginous drinks freely1 so as to produce vomiting4 ,,alcohol4--,brandy1 wine2 all spirituous liquors4 ,,antidote4--,give as an emetic ground mustard or tartar emetic4 ,if the patient cannot swallow1 introduce a stomach pump2 pour cold water on the head4 ,,gases4--,chlorine1 carbonic acid gas1 carbonic oxide1 fumes of burning charcoal1 sulphuretted hydrogen1 illuminating or coal-gas4 ,,antidote4--,for poisoning by chlorine1 inhale1 cautiously1 ammonia 7hartshorn74 ,for the other gases1 cold water should be poured upon the head1 and stimulants cautiously administered2 artificial respiration4 7,see ,marshall ,hall's ,ready ,method1 page #bej47 ,,metals4--,antimony1 tartar emetic1 wine of antimony1 etc4 ,,antidote4--,if vomiting has not occurred1 it should be produced by tickling the throat with the finger or a feather1 and the abundant use of warm water4 ,astringent infusions1 such as common tea1 oak bark1 and solution of tannin1 act as antidotes4 ,,arsenic4--,white arsenic1 ,fowler's solution1 fly-powder1 cobalt1 ,paris green1 etc4 ,,antidote4--,produce vomiting at once with a tablespoonful or two of powdered mustard in a glass of warm water1 or with ipecac4 ,the antidote is hydrated peroxide of iron4 ,if ,fowler's solution has been taken1 lime-water must be given4 #bdi ,,copper4--,acetate of copper 7verdigris71 sulphate of copper 7blue vitriol71 food cooked in dirty copper vessels1 or pickles made green by copper4 ,,antidote4--,milk or white of eggs1 with mucilaginous drinks 7flaxseed tea1 etc471 should be freely given4 ,,iron4--,sulphate of iron 7copperas71 etc4 ,,antidote4--,carbonate of soda in some mucilaginous drink1 or in water1 is an excellent antidote4 ,,lead4--,acetate of lead 7sugar of lead71 carbonate of lead 7white lead71 water kept in leaden pipes or vessels1 food cooked in vessels glazed with lead4 ,,antidote4--,induce vomiting with ground mustard or common salt in warm water4 ,the antidote for soluble preparations of lead is ,epsom salts2 for the insoluble forms1 sulphuric acid largely diluted4 ,,mercury4--,bichloride of mercury 7corrosive sublimate71 ammoniated mercury 7white precipitate71 red oxide of mercury 7red precipitate71 red sulphuret of mercury 7vermilion74 ,,antidote4--,the white of eggs1 or wheat flour beaten up with water and milk1 are the best antidotes4 ,,silver4--,nitrate of silver 7lunar caustic74 ,,antidote4--,give a teaspoonful of common salt in a tumbler of water4 ,it decomposes the salts of silver and destroys their activity4 ,,zinc4--,sulphate of zinc1 etc4 7white vitriol74 ,,antidote4--,the vomiting may be relieved by copious draughts of warm water4 ,the antidote is carbonate of soda administered in water4 ,,narcotic ,,poisons4--,opium 7laudanum1 paregoric1 salts of morphia1 ,godfrey's cordial1 ,dalby's carminative1 soothing syrup1 cholera mixtures71 aconite1 belladonna1 hemlock1 stramonium1 digitalis1 tobacco1 hyosciamus1 nux vomica1 strychnine4 ,,antidote4--,evacuate the stomach by the most active emetics1 as mustard1 alum1 or sulphate of zinc4 ,the patient should be kept in motion1 and cold water dashed on the head and shoulders4 ,strong coffee must be given4 ,the physician will use the stomach pump and electricity4 ,in poisoning by nux vomica or strychnine1 etc41 chloroform or ether should be inhaled to quiet the spasms4 ,,irritant ,,vegetable ,,poisons4--,croton oil1 oil of savine1 poke1 oil of tansy1 etc4 ,,antidote4--,if vomiting has taken place1 it may be rendered easier by copious draughts of warm water4 ,but if symptoms of insensibility have come on without vomiting1 it ought to be immediately excited by ground mustard mixed with warm water1 or some other active emetic #bej and after its operation an active purgative should be given4 ,after evacuating as much of the poison as possible1 strong coffee or vinegar and water may be given with advantage4 ,,poisonous ,,fish4--,conger eel1 mussels1 crabs1 etc4 ,,antidote4--,evacuate1 as soon as possible1 the contents of the stomach and bowels by emetics 7ground mustard mixed with warm water or powdered alum71 and castor oil1 drinking freely at the same time of vinegar and water4 ,ether1 with a few drops of laudanum mixed with sugar and water1 may afterward be taken freely4 ,,poisonous ,,serpents4--,,antidote4--,a ligature or handkerchief should be applied moderately tight above the bite1 and a cupping-glass over the wound4 ,the patient should drink freely of alcoholic stimulants containing a small quantity of ammonia4 ,the physician may inject ammonia into the veins4 ,,poisonous ,,insects4--,stings of scorpion1 hornet1 wasp1 bee1 etc4 ,,antidote4--,a piece of rag moistened with a solution of carbolic acid may be kept on the affected part until the pain is relieved2 and a few drops of carbolic acid may be given frequently in a little water4 ,the sting may be removed by making strong pressure around it with the barrel of a small watch-key4 ,,drowning4 ,,marshall ,,hall',s ,,ready ,,method of treatment in asphyxia from drowning1 chloroform1 coal gas1 etc4 #ast4 ,treat the patient instantly on the spot1 in the open air1 freely exposing the face1 neck1 and chest to the breeze1 except in severe weather4 #b;d4 ,in order to clear the throat1 place the patient gently on the face1 with one wrist under the forehead1 that all fluid1 and the tongue itself1 may fall forward1 and leave the entrance into the windpipe free4 #c;d4 ,to excite respiration1 turn the patient slightly on his side1 and apply some irritating or stimulating agent to the nostrils1 as veratrine1 dilute ammonia1 etc4 #dth4 ,make the face warm by brisk friction2 then dash cold water upon it4 #eth4 ,if not successful1 lose no time2 but1 to imitate respiration1 place the patient on his face1 and turn the body gently1 but completely on the side1 and a little beyond2 then again on the face1 and so on1 alternately4 ,repeat these movements1 deliberately and perseveringly1 #bea fifteen times only in a minute4 7,when the patient lies on the thorax1 this cavity is compressed by the weight of the body1 and expiration takes place4 ,when he is turned on the side1 this pressure is removed1 and inspiration occurs47 #fth4 ,when the prone position is resumed1 make a uniform and efficient pressure along the spine1 removing the pressure immediately1 before rotation on the side4 7,the pressure augments the expiration3 the rotation commences inspiration47 ,continue these measures4 #gth4 ,rub the limbs upward1 with firm pressure and with energy4 7,the object being to aid the return of venous blood to the heart47 #hth4 ,substitute for the patient's wet clothing1 if possible1 such other covering as can be instantly procured1 each bystander supplying a coat or cloak1 etc4 ,meantime1 and from time to time1 to excite inspiration1 let the surface of the body be slapped briskly with the hand4 #ith4 ,rub the body briskly till it is dry and warm1 then dash cold water upon it1 and repeat the rubbing4 ,avoid the immediate removal of the patient1 as it involves a dangerous loss of time--also1 the use of bellows1 or any forcing instrument2 also1 the warm bath1 and all rough treatment4 99 99 99 99 99 #beb ,,glossary4 ------o------ ,,ab-,,do,,men 7,latin abdo1 to conceal74 ,the largest cavity of the body containing the liver1 stomach1 intestines1 etc42 the belly4 ,,ab-,,sor,,bents 7,l4 ab and sorbeo1 to suck up74 ,the vessels which take part in the process of absorption4 ,,ab-,,sorp,,tion4 ,the process of sucking up fluids by means of an animal membrane4 ,,ac-,,com-,,mo-,,da,,tion of the ,eye4 ,the alteration in the shape of the crystalline lens1 which accommodates or adjusts the eye for near and remote vision4 ,,ac,,id1 ,,lactic 7,l4 lac1 milk74 ,the acid ingredient of sour milk2 the gastric juice also contains it4 ,,al-,,bu,,men1 or ,albumin 7,l4 albus1 white74 ,an animal substance resembling white of egg4 ,,al-,,bu,,mi-,,nose 7from albumen74 ,a soluble animal substance produced in the stomach by the digestion of the albuminoid substances4 ,,al-,,bu,,min-,,oid substances4 ,a class of proximate principles resembling albumen2 they may be derived from either the animal or vegetable kingdoms4 ,,al,i-,,ment 7,l4 alo1 to nourish74 ,that which affords nourishment2 food4 ,,al-,i-,,ment,a-,,ry ,,ca-,,nal 7from aliment74 ,a long tube in which the food is digested1 or prepared for reception into the system4 ,,an-,s-,,thet,,ics 7,greek1 ,greek3 an1 an1 without1 ,greek3 aisthesia1 aisthesia1 feeling74--,those medicinal agents which prevent the feeling of pain1 such as chloroform1 laughing-gas1 etc4 ,,an-,i-,,mal,,cule 7,l4 animalculum1 a small animal74 ,applied to animals which can only be seen with the aid of the microscope4 ,animalculum 7plural1 animalcula7 is used with the same meaning4 ,a-,,or,,ta 7,gr4 ,greek3 aorteomai1 aorteomai1 to be lifted up74 ,the largest artery of the body1 and main trunk of all the arteries4 ,it arises from the left ventricle of the heart4 ,the name was first applied to the two large branches of the trachea1 which appear to be lifted up by the heart4 #bec ,a,,que-,,ous ,,humor 7,l4 aqua1 water74 ,a few drops of watery colorless fluid occupying the space between the cornea and crystalline lens4 ,a-,,rach,,noid ,,mem,,brane 7,gr4 ,greek3 arachne1 arachne1 a cobweb1 and ,greek3 eidos1 eidos1 like74 ,an extremely thin covering of the brain and spinal cord4 ,it lies between the dura mater and the pia mater4 ,,ar,,bor ,,vi,t 7,l474 ,literally1 the tree of life2 a name given to the peculiar appearance presented by a section of the cerebellum4 ,,ar,,ter-,y 7,gr4 ,greek3 aer1 aer1 air1 and ,greek3 terein1 terein1 to contain74 ,a vessel by which blood is conveyed away from the heart4 ,it was supposed by the ancients to contain air2 hence the name4 ,,ar-,,tic-,u-,,la,,tion 7,l4 articulo1 to form a joint74 ,the more or less movable union of bones1 etc42 a joint4 ,a-,,ryt,e-,,noid ,,car,,ti-,,la-,,ges 7,gr4 ,greek3 arutaina1 arutaina1 a pitcher74 ,two small cartilages of the larynx1 resembling the mouth of a pitcher4 ,,as-,,sim-,i-,,la,,tion 7,l4 ad1 to1 and similis1 like74 ,the conversion of food into living tissue4 ,,au-,,di,,tion 7,l4 audio1 to hear74 ,the act of hearing sounds4 ,,au,,di-,,to-,,ry ,,nerve4 ,one of the cranial nerves2 it is the special nerve of hearing4 ,,au,,ri-,,cle 7,l4 auris1 the ear74 ,a cavity of the heart4 ,,bar,i-,,tone 7,gr4 ,greek3 barus1 barus1 heavy1 and ,greek3 tonos1 tonos1 tone74 ,a variety of male voice between the bass and tenor4 ,,bel-,,la-,,don,,na 7,it4 beautiful lady74 ,a vegetable narcotic poison4 ,it has the property of enlarging the pupil1 and thus increasing the brilliancy of the eye2 so called from its use by ,italian ladies4 ,,bi-,,cus,,pid 7,l4 bi1 two1 and cuspis1 prominence74 ,the name of the fourth and fifth teeth on each side of the jaw2 possessing two prominences4 ,,bile4 ,the gall1 or peculiar secretion of the liver2 a viscid1 yellowish fluid1 and very bitter to the taste4 ,,bronch,i 7,gr4 ,greek3 bronkos1 bronkos1 the windpipe74 ,the two first divisions or branches of the trachea2 one enters each lung4 ,,bronch,i-,,al ,,tubes4 ,the smaller branches of the trachea within the substance of the lungs1 terminating in the air-cells4 ,,bronch-,i,,tis 7from bronchia1 and itis1 a suffix signifying inflammation74 ,an inflammation of the larger bronchial tubes2 a cold affecting the lungs4 ,,cal-,,ca,,re-,,ous 7,l4 calx1 lime74 ,containing lime4 ,,ca-,,nal 7,l474 ,in the body1 any tube or passage4 ,,ca-,,nine 7,l4 canis1 a dog74 ,name given to the third tooth on each #bed side of the jaw2 in the upper jaw it is also known as the eye-tooth3 pointed like the tusks of a dog4 ,,cap,,il-,,la-,,ry 7,l4 capillus1 a hair1 capillaris hair-like74 ,the name of the extremely minute blood-vessels which connect the arteries with the veins4 ,,car,,bon ,,diox-,,ide 7,,co#b74 ,chemical name for carbonic acid gas4 ,,car-,,bon,,ic ,a-,,cid4 ,the gas which is present in the air expired from the lungs2 a waste product of the animal kingdom1 and a food of the vegetable kingdom4 ,,car,,di-,,ac 7,gr4 ,greek3 kardia1 cardia1 the heart74 ,the cardiac orifice of the stomach is the upper one1 and is near the heart2 hence its name4 ,,car-,,niv,o-,,rous 7,l4 caro1 flesh1 and voro1 to devour74 ,subsisting upon flesh4 ,,ca-,,rot,,id ,,ar-,,te-,,ry4 ,the large artery of the neck1 supplying the head and brain4 ,,car,,ti-,,lage4 ,a solid but flexible material1 forming a part of the joints1 air-passages1 nostrils1 etc42 gristle4 ,,ca,,se-,,ine 7,l4 caseus1 cheese74 ,the albuminoid substance of milk2 it forms the basis of cheese4 ,,cer-,e-,,bel,,lum 7diminutive for cerebrum1 the brain74 ,the little brain1 situated beneath the posterior third of the cerebrum4 ,,cer,e-,,brum 7,l474 ,the brain proper1 occupying the entire upper portion of the skull4 ,it is nearly divided into two equal parts1 called hemispheres1 by a cleft extending from before backward4 ,,cho,,roid 7,gr4 ,greek3 chorion1 chorion1 a membrane or covering74 ,the middle tunic or coat of the eyeball4 ,,chyle 7,gr4 ,greek3 chulos1 chulos1 juice74 ,the milk-like fluid formed by the digestion of fatty articles of food in the intestines4 ,,chyme 7,gr4 ,greek3 chumos1 chumos1 juice74 ,the pulpy liquid formed by digestion within the stomach4 ,,cil,i-,a 7pl4 of cili-um1 an eyelash74 ,minute1 vibratile1 hair-like processes found upon the cells of the air-passages1 and other parts that are habitually moist4 ,,cir-,,cu-,,la,,tion 7,l4 circulus1 a ring74 ,the circuit1 or course of the blood through the blood-vessels of the body1 from the heart to the arteries1 through the capillaries into the veins1 and from the veins back to the heart4 ,,co-,,ag-,u-,,la,,tion 7,l4 coagulo1 to curdle74 ,applied to the process by which the blood clots or solidifies4 ,,coch,,le-,a 7,l4 cochlea1 a snail-shell74 ,the spiral cavity of the internal ear4 #bee ,,conch,a 7,gr4 ,greek3 konch1 konche1 a mussel-shell74 ,the external shell-shaped portion of the external ear4 ,,con-,,junc-,,ti,,va 7,l4 con and jungo1 to join together74 ,a thin layer of mucous membrane which lines the eyelids and covers the front of the eyeball2 thus joining the latter to the lids4 ,,con-,,trac-,,til,i-,,ty 7,l4 con and traho1 to draw together74 ,the property of a muscle which enables it to contract1 or draw its extremities closer together4 ,,con-,,vo-,,lu,,tions 7,l4 con and volvo1 to roll together74 ,the tortuous foldings of the external surface of the brain4 ,,con-,,vul,,sion 7,l4 convello1 to pull together74 ,a more or less violent agitation of the limbs or body4 ,,cor,,ne-,a 7,l4 cornu1 a horn74 ,the transparent1 horn-like substance which covers the anterior fifth of the eyeball4 ,,cor,,pus-,,cles1 ,,blood 7,l4 dim4 of corpus1 a body74 ,the small biconcave disks which give to the blood its red color2 the white corpuscles are globular and larger4 ,,cos-,,met,,ic 7,gr4 ,greek3 kosme1 kosmeo1 to adorn74 ,beautifying2 applied to articles which are supposed to increase the beauty of the skin1 etc4 ,,cra,,ni-,,al 7,l4 cranium1 the skull74 ,pertaining to the skull4 ,the nerves which arise from the brain are called cranial nerves4 ,,cri,,coid 7,gr4 ,greek3 krikos1 krikos1 a ring74 ,a cartilage of the larynx1 resembling a seal-ring in shape4 ,,crys,,tal-,,line ,,lens 7,l4 crystallum1 a crystal74 ,one of the so-called humors of the eye2 a double convex body situated in the front part of the eyeball4 ,,cu,,ti-,,cle 7,l4 dim4 of cutis1 the skin74 ,the scarf-skin2 also called the epidermis4 ,,cu,,tis 7,gr4 ,greek3 skutos1 skutos1 a skin or hide74 ,the true skin1 lying beneath the cuticle2 also called the derma4 ,,de-,,cus-,,sa,,tion 7,l4 decussis1 the ,roman numeral ten1 ,x74 ,a reciprocal crossing of fibres from side to side4 ,,di,a-,,phragm 7,gr4 ,greek3 diaphrass1 diaphrasso1 to divide by a partition74 ,a large1 thin muscle which separates the cavity of the chest from the abdomen2 a muscle of respiration4 ,,dif-,,fus,,ion ,,of ,,gases4 ,the power of gases to become intimately mingled1 without reference to the force of gravity4 ,,duct 7,l4 duco1 to lead74 ,a narrow tube2 the thoracic duct is the main trunk of the absorbent vessels4 ,,du-,o-,,de,,num 7,l4 duodeni1 twelve74 ,the first division of the small intestines1 about twelve fingers-breadth long4 #bef ,,du,,ra ,,ma,,ter 7,l474 ,literally1 the hard mother2 the tough membrane which envelops the brain4 ,,dys-,,pep,,si-,a 7,gr4 ,greek3 dus1 dus1 difficult1 and ,greek3 pept1 pepto1 to digest74 ,difficult or painful digestion2 a disordered condition of the stomach4 ,e-,,mul,,sion 7,l4 emulgeo1 to milk74 ,oil in a finely divided state suspended in water4 ,,en-,,am,,el 7,fr4 email74 ,the dense material which covers the crown of the tooth4 ,,en,,er-,,gy1 ,specific1 of a ,nerve4 ,when a nerve of special sense is excited1 whatever be the cause1 the sensation experienced is that peculiar to the nerve2 this is said to be the law of the specific energy of the nerves4 ,,ep-,i-,,glot,,tis 7,gr4 ,greek3 epi1 epi1 upon1 and ,greek3 glttis1 glottis1 the entrance to the windpipe74 ,a leaf-shaped piece of cartilage which covers the top of the larynx during the act of swallowing4 ,,ex-,,cre,,tion 7,l4 excerno1 to separate74 ,the separation from the blood of the waste particles of the body2 also the materials excreted4 ,,ex-,,pi-,,ra,,tion 7,l4 expiro1 to breathe out74 ,the act of forcing air out of the lungs4 ,,ex-,,ten,,sion 7,l4 ex1 out1 and tendo1 to stretch74 ,the act of restoring a limb1 etc41 to its natural position after it has been flexed1 or bent2 the opposite of ,flexion4 ,,fe-,,nes,,tra 7,l474 ,literally1 a window2 the opening between the middle and internal ear4 ,,fi,,brin 7,l4 fibra1 a fibre74 ,an albuminoid substance found in the blood2 in coagulating it assumes a fibrous form4 ,,flex,,ion 7,l4 flecto1 to bend74 ,the act of bending a limb1 etc4 ,,fol,,li-,,cle 7,l4 dim4 of follis1 a bag74 ,a little pouch or depression in a membrane2 it has generally a secretory function4 ,,fun,,gous ,,growths 7,l4 fungus1 a mushroom74 ,a low grade of vegetable life4 ,,gan,,gli-,,on 7,gr4 ,greek3 ganglion1 ganglion1 a knot74 ,a knot-like swelling in the course of a nerve2 a smaller nerve-centre4 ,,gas,,tric 7,gr4 ,greek3 gastr1 gaster1 stomach74 ,pertaining to the stomach4 ,,gland 7,l4 glans1 an acorn74 ,an organ consisting of follicles and ducts1 with numerous blood-vessels interwoven2 it separates some particular fluid from the blood4 ,,glos,,so-,,phar-,,yn-,,ge,,al ,,nerve 7,gr4 ,greek3 glssa1 glossa1 the tongue1 and ,greek3 pharunx1 pharunx1 the throat74 ,the nerve of taste supplying the posterior third of the tongue2 it also supplies the throat4 ,,glu,,ten 7,l474 ,literally1 glue3 the glutinous albuminoid ingredient of wheat4 #beg ,,gran,,ule 7,l4 dim4 of granum1 a grain74 ,a little grain2 a microscopic object4 ,,gus-,,ta,,tion 7,l4 gusto1 to taste7 ,the sense of taste4 ,,gus,,ta-,,to-,,ry ,,nerve4 ,the nerve of taste supplying the front part of the tongue2 a branch of the fifth pair4 ,h,m,,or-,,rhage 7,gr4 ,greek3 haima1 haima1 blood1 and ,greek3 rhgnumi1 regnumi1 to burst74 ,bleeding1 or the loss of blood4 ,,hem-,i-,,ple,,gia 7,gr4 ,greek3 hmisus1 hemisus1 half1 and ,greek3 plss1 plesso1 to strike74 ,paralysis1 or loss of power1 affecting one side of the body4 ,,hem,i-,,spheres 7,gr4 ,greek3 sphaira1 sphaira1 a sphere74 ,half a sphere1 the lateral halves of the cerebrum1 or brain proper4 ,,he-,,pat,,ic 7,gr4 ,greek3 hpar1 hepar1 the liver74 ,pertaining to the liver4 ,,her-,,biv,o-,,rous 7,l4 herba1 an herb1 and voro to devour74 ,applied to animals that subsist upon vegetable food4 ,,hu,,mor 7,l474 ,moisture3 the humors are transparent contents of the eyeball4 ,,hy-,,dro-,,pho,,bi-,a 7,gr4 ,greek3 hudor1 hudor1 water1 and ,greek3 phobe1 phobeo1 to fear74 ,a disease caused by the bite of a rabid dog or other animal4 ,in a person affected with it1 convulsions are occasioned by the sight of a glittering object1 like water1 by the sound of running water1 and by almost any external impression4 ,,hy,,gi-,,ene 7,gr4 ,greek3 hugieia1 huygieia1 health74 ,the art of preserving health and preventing disease4 ,,hy,,per-,o-,,pi-,a4 ,abbreviated from ,,hy,,per-,,met-,,ro,,pi-,a 7,gr4 ,greek3 huper1 huper1 beyond1 ,greek3 metron1 metron1 the measure1 and ,greek3 ps1 ops1 the eye74 ,a defect of vision dependent upon a too short eyeball2 so called because the rays of light are brought to a focus at a point behind the retina2 the true far sight4 ,,in-,,ci,,sor 7,l4 incido1 to cut74 ,applied to the four front teeth of both jaws1 which have sharp cutting edges4 ,,in,,cus 7,l74 ,an anvil2 the name of one of the bones of the middle ear4 ,,in-,,sal-,i-,,va,,tion 7,l4 in1 and saliva1 the fluid of the mouth74 ,the mingling of the saliva with the food during the act of chewing4 ,,in-,,spi-,,ra,,tion 7,l4 in1 and spiro1 spiratum1 to breathe74 ,the act of drawing in the breath4 ,,in-,,teg,u-,,ment 7,l4 in1 and tego1 to cover74 ,the skin1 or outer covering of the body4 ,,in-,,tes,,tine 7,l4 intus1 within74 ,the part of the alimentary canal which is continuous with the lower end of the stomach2 also called the intestines1 or the bowels4 ,i,,ris 7,l4 iris1 the rainbow74 ,the thin muscular ring which lies #beh between the cornea and crystalline lens1 and which gives the eye its brown1 blue1 or other color4 ,,ju,,gu-,,lar 7,l4 jugulum1 the throat74 ,the name of the large veins which run along the front of the neck4 ,,lab,y-,,rinth 7,gr4 ,greek3 laburinthos1 laburinthos1 a building with many winding passages74 ,the very tortuous cavity of the inner ear1 comprising the vestibule1 semicircular canals1 and the cochlea4 ,,lach,,ry-,,mal ,,apparatus 7,l4 lachryma1 a tear74 ,the organs for forming and conveying away the tears4 ,,lac,,te-,,als 7,l4 lac1 lactis1 milk74 ,the absorbent vessels of the small intestines2 during digestion they are filled with chyle1 which has a milky appearance4 ,,la-,,ryn,,go-,,scope 7,gr4 ,greek3 larunx1 larunx1 the larynx1 and ,greek3 skope1 skopeo1 to look at74 ,the instrument by which the larynx may be examined in the living subject4 ,,lar,,ynx 7,gr474 ,the cartilaginous tube situated at the top of the windpipe1 or trachea2 the organ of the voice4 ,,lens 7,l474 ,literally1 a lentil2 a piece of transparent glass or other substance so shaped as either to converge or disperse the rays of light4 ,,lig,a-,,ment 7,l4 ligo1 to bind74 ,a strong1 fibrous material binding bones or other solid parts together2 it is especially necessary to give strength to joints4 ,,lig,a-,,ture4 ,a thread of silk or other material used in tying around an artery4 ,,lymph 7,l4 lympha1 spring-water74 ,the colorless1 watery fluid conveyed by the lymphatic vessels4 ,,lym-,,phat,,ic ,,vessels4 ,a system of absorbent vessels4 ,,mal,,le-,,us 7,l474 ,literally1 the mallet2 one of the small bones of the middle ear4 ,,mar,,row4 ,the soft1 fatty substance contained in the central cavities of the bones3 the spinal marrow1 however1 is composed of nervous tissue4 ,,mas-,,ti-,,ca,,tion 7,l4 mastico1 to chew74 ,the act of cutting and grinding the food to pieces by means of the teeth4 ,,me-,,dul,,la ,,ob-,,lon-,,ga,,ta4 ,the oblong marrow1 or nervous cord1 which is continuous with the spinal cord within the skull4 ,,mem-,,bra,,na ,,tym,,pan-,i 7,l474 ,literally1 the membrane of the drum2 a delicate partition separating the outer from the middle ear2 it is sometimes incorrectly called the drum of the ear4 ,,mem,,brane4 ,a thin layer of tissue serving to cover some part of the body4 ,,mi,,cro-,,scope 7,gr4 ,greek3 mikros1 mikros1 small1 and ,greek3 skope1 skopeo1 to #bei look at74 ,an optical instrument which assists in the examination of minute objects4 ,,mo,,lar 7,l4 mola1 a mill74 ,the name applied to the three back teeth of each side of the jaw2 the grinders1 or mill-like teeth4 ,,mo,,tor 7,l4 moveo1 motum1 to move74 ,causing motion2 the name of those nerves which conduct to the muscles the stimulus which causes them to contract4 ,,mu,,cous ,,membrane4 ,the thin layer of tissue which covers those internal cavities or passages which communicate with the external air4 ,,mu,,cus4 ,the glairy fluid which is secreted by mucous membranes1 and which serves to keep them in a moist condition4 ,,my-,o,,pi-,a 7,gr4 ,greek3 mu1 muo1 to contract1 and ,greek3 ps1 ops1 the eye74 ,a defect of vision dependent upon an eyeball that is too long1 rendering distant objects indistinct2 near-sight4 ,,na,,sal 7,l4 nasus1 the nose74 ,pertaining to the nose2 the nasal cavities contain the distribution of the special nerve of smell4 ,,nerve 7,gr4 ,greek3 neuron1 neuron1 a cord or string74 ,a glistening1 white cord of cylindrical shape1 connecting the brain or spinal cord with some other organ of the body4 ,,nerve ,,cell4 ,a minute1 round and ashen-gray cell found in the brain and other nervous centres4 ,,nerve ,,fi,,bre4 ,an exceedingly slender thread of nervous tissue found in the various nervous organs1 but especially in the nerves2 it is of a white color4 ,,nu-,,tri,,tion 7,l4 nutrio1 to nourish74 ,the processes by which the nourishment of the body is accomplished4 ,,oe-,,soph,a-,,gus 7,gr474 ,literally1 that which carries food4 ,the tube leading from the throat to the stomach2 the gullet4 ,o-,,le-,,ag,i-,,nous 7,l4 oleum1 oil74 ,of the nature of oil3 applied to an important group of food-principles--the fats4 ,,ol-,,fac,,to-,,ry 7,l4 olfacio1 to smell74 ,pertaining to the sense of smell4 ,,oph-,,thal,,mo-,,scope 7,gr4 ,greek3 ophthalmos1 ophthalmos1 the eye1 and ,greek3 skope1 skopeo1 to look at74 ,an instrument devised for examining the interior of the globe of the eye4 ,,op,,tic 7,gr4 ,greek3 opt1 opto1 to see74 ,pertaining to the sense of sight4 ,,or,,bit 7,l4 orbis1 the socket74 ,the bony socket or cavity in which the eyeball is situated4 ,,os,,mose 7,gr4 ,greek3 smos1 osmos1 a thrusting or impulsion74 ,the process by which liquids are impelled through a moist membrane4 ,,os,,se-,,ous 7,l4 os1 a bone74 ,consisting of1 or resembling bone4 ,,pal,,ate 7,l4 palatum1 the palate74 ,the roof of the mouth1 consisting of the hard and soft palate4 #bfj ,,pal,,mar4 ,relating to the palm of the hand4 ,,pan,,cre-,,as 7,gr4 ,greek3 pas1 ,greek3 pantos1 pas1 pantos1 all1 and ,greek3 kreas1 kreas1 flesh74 ,a long1 flat gland situated near the stomach2 in the lower animals the analogous organ is called the sweet-bread4 ,,pa-,,pil,l 7,l4 papilla74 ,the minute prominences in which terminate the ultimate fibres of the nerves of touch and taste4 ,,pa-,,ral,y-,,sis4 ,a disease of the nervous system marked by the loss of sensation1 or voluntary motion1 or both2 palsy4 ,,par-,a-,,ple,,gi-,a 7,gr4 ,greek3 paraplss1 paraplesso1 to strike amiss74 ,a form of paralysis affecting the lower half of the body4 ,,pa-,,tel,,la 7,l4 dim4 of patina1 a pan74 ,the knee-pan2 a small bone4 ,,pel,,vis 7,l474 ,literally a basin2 the bony cavity at the lower part of the trunk4 ,,pep,,sin 7,gr4 ,greek3 pept1 pepto1 to digest74 ,the organic principle of the gastric juice4 ,,per-,i-,,stal,,tic ,,move,,ments 7,gr4 ,greek3 peristell1 peristello1 to contract74 ,the slow1 wave-like movements of the stomach and intestines4 ,,per-,i-,,to-,,ne,,um 7,gr4 ,greek3 peritein1 periteino1 to stretch around74 ,the investing membrane of the stomach1 intestines1 and other abdominal organs4 ,,per-,,spi-,,ra,,tion 7,l4 perspiro1 to breathe through74 ,the sweat1 or watery exhalation of the skin2 when visible1 it is called sensible perspiration1 when invisible1 it is called insensible perspiration4 ,,pe,,trous 7,gr4 ,greek3 petra1 petra1 a rock74 ,the name of the hard portion of the temporal bone1 in which is situated the drum of the ear and labyrinth4 ,,phar,,ynx 7,gr4 ,greek3 pharunx1 pharunx1 the throat74 ,the cavity between the back of the mouth and gullet4 ,,phys-,i-,,ol,o-,,gy 7,gr4 ,greek3 phusis1 phusis1 nature1 and ,greek3 logos1 logos1 a discourse74 ,the science of the functions of living1 organized beings4 ,,pi,a ,,ma,,ter 7,l474 ,literally1 the tender mother2 the innermost of the three coverings of the brain4 ,it is thin and delicate2 hence the name4 ,,pleu,,ra 7,gr4 ,greek3 pleura1 a rib74 ,a membrane covering the lung and lining the chest4 ,there is one for each lung4 ,,pleu,,ri-,,sy4 ,an inflammation affecting the pleura4 ,,pneu-,,mo-,,gas,,tric 7,gr4 ,greek3 pneumn1 pneumon1 the lungs1 and ,greek3 gastr1 gaster1 the stomach74 ,the name of a nerve distributed to the lungs and stomach2 it is the principal nerve of respiration4 ,,pneu-,,mo,,nia 7,gr474 ,an inflammation affecting the air-cells of the lungs4 #bfa ,,pres-,,by-,o,,pi-,a 7,gr4 ,greek3 presbus1 presbus1 old1 and ,greek3 ps1 ops1 the eye74 ,a defect of the accommodation of the eye1 caused by the hardening of the crystalline lens2 the far-sight of adults and aged persons4 ,,proc,,ess 7,l4 procedo1 processus1 to proceed1 to go forth74 ,any projection from a surface4 ,also1 a method of performance2 a procedure4 ,,pty,a-,,lin 7,gr4 ,greek3 ptualon1 ptualon1 saliva74 ,the peculiar organic ingredient of the saliva4 ,,pul,,mo-,,na-,,ry 7,l4 pulmo1 pulmonis1 the lungs74 ,pertaining to the lungs4 ,,pulse 7,l4 pello1 pulsum1 to beat74 ,the striking of an artery against the finger1 occasioned by the contraction of the heart1 commonly felt at the wrist4 ,,pu,,pil 7,l4 pupilla74 ,the central1 round opening in the iris1 through which light passes into the depths of the eye4 ,,py-,,lo,,rus 7,gr4 ,greek3 pulros1 puloros1 a gate-keeper74 ,the lower opening of the stomach1 at the beginning of the small intestine4 ,,re,,flex ,,action4 ,an involuntary action of the nervous system1 by which an external impression conducted by a sensory nerve is reflected1 or converted into a motor impulse4 ,,res-,,pi-,,ra,,tion 7,l4 respiro1 to breathe frequently74 ,the function of breathing1 comprising two acts3 inspiration1 or breathing in1 and expiration1 or breathing out4 ,,ret,i-,,na 7,l4 rete1 a net74 ,the innermost of the three tunics or coats of the eyeball1 being an expansion of the optic nerve4 ,,sac,,cha-,,rine 7,l4 saccharum1 sugar74 ,of the nature of sugar2 applied to the important group of food substances which embraces the different varieties of sugar1 starch1 and gum4 ,,sa-,,li,,va 7,l474 ,the moisture or fluids of the mouth1 secreted by the salivary glands1 etc4 ,,scle-,,rot,,ic 7,gr4 ,greek3 sklros1 skleros1 hard74 ,the tough1 fibrous outer tunic of the eyeball4 ,,se-,,ba,,ceous 7,l4 sebum1 fat74 ,resembling fat1 the name of the oily secretion by which the skin is kept flexible and soft4 ,,se-,,cre,,tion 7,l4 secerno1 secretum1 to separate74 ,the process of separating from the blood some essential important fluid2 which fluid is also called a secretion4 ,,sem-,i-,,cir,,cu-,,lar ,,canals4 ,a portion of the internal ear4 ,,sen-,,sa,,tion4 ,the perception of an external impression by the nervous system2 a function of the brain4 ,,sen-,,si-,,bil,i-,,ty1 ,,general4 ,the power possessed by nearly all parts #bfb of the human body of recognizing the presence of foreign objects that come in contact with them4 ,,se,,rum 7,l474 ,the watery constituent of the blood1 which separates from the clot during the process of coagulation4 ,,skel,e-,,ton 7,gr474 ,the bony framework of an animal1 the different parts of which are maintained in their proper relative positions4 ,,spec,,tro-,,scope 7from spectrum and ,greek3 skope1 scopeo1 to examine the spectrum74 ,an instrument employed in the examination of the spectrum of the sun or any other luminous body4 ,,sphyg,,mo-,,graph 7,gr4 ,greek3 sphugmos1 sphugmos1 the pulse1 and ,greek3 graph1 grapho1 to write74 ,an ingenious instrument by means of which the pulse is delineated upon paper4 ,,sta,,pes 7,l474 ,literally1 a stirrup2 one of the small bones of the tympanum1 or middle ear1 resembling somewhat a stirrup in shape4 ,,sym-,,pa-,,thet,,ic ,,system ,,of ,,nerves4 ,a double chain of nervous ganglia1 connected together by numerous small nerves1 situated chiefly in front of and on each side of the spinal column4 ,,syn-,o,,vi-,a 7,gr4 ,greek3 sun1 sun1 and ,greek3 on1 oon1 resembling an egg74 ,the lubricating fluid of joints1 so called because it resembles the white of egg4 ,,sys,,to-,,le 7,gr4 ,greek3 sustell1 sustello1 to contract74 ,the contraction of the heart1 by which the blood is expelled from that organ4 ,,tac,,tile 7,l4 tactus1 touch74 ,relating to the sense of touch4 ,,tem,,po-,,ral 7,l4 tempus1 time1 and tempora1 the temples74 ,pertaining to the temples2 the name of an artery3 so called1 because the hair begins to turn white with age in that portion of the scalp4 ,,ten,,don 7,l4 tendo1 to stretch74 ,the white1 fibrous cord or band by which a muscle is attached to a bone2 a sinew4 ,,tet,a-,,nus 7,gr4 ,greek3 tein1 teino1 to stretch74 ,a disease marked by persistent contractions of all or some of the voluntary muscles2 those of the jaw are sometimes solely affected3 the disorder is then termed locked-jaw4 ,,tho,,rax 7,gr4 ,greek3 thrax1 thorax1 a breastplate74 ,the upper cavity of the trunk of the body1 containing the lungs1 heart1 etc42 the chest4 ,,thy,,roid 7,gr4 ,greek3 thureos1 thureos1 a shield74 ,the largest of the cartilages of the larynx2 its angular projection in the front of the neck is called ,adam's apple4 ,,tra,,che-,a 7,gr4 ,greek3 trachus1 trachus1 rough74 ,the windpipe1 or the largest of the air-passages2 composed in part of cartilaginous rings1 which render its surface rough and uneven4 ,,trans-,,fu,,sion 7,l4 transfundo1 to pour from one vessel to another74 #bfc ,the operation of injecting blood taken from one person into the veins of another2 other fluids than blood are sometimes used4 ,,trich-,i,,na ,,spi-,,ra,,lis4 7,l47 ,a minute species of parasite or worm1 which infests the flesh of the hog1 and which may be introduced into the human system by eating pork not thoroughly cooked4 ,,tym,,pa-,,num 7,gr4 ,greek3 tumpanon1 tumpanon1 a drum74 ,the cavity of the middle ear1 resembling a drum in being closed by two membranes1 and in having communication with the atmosphere4 ,u,,vu-,,la 7,l4 uva1 a grape74 ,the small pendulous body attached to the back part of the palate4 ,,vas,,cu-,,lar 7,l4 vasculum1 a little vessel74 ,pertaining to1 or containing blood-vessels4 ,,ve,,nous 7,l4 vena1 a vein74 ,pertaining to1 or contained within a vein4 ,,ven-,,ti-,,la,,tion4 ,the introduction of fresh air into a room or building1 in such a manner as to keep the air within it in a pure condition4 ,,ven-,,tril,o-,,quism 7,l4 venter1 the belly1 and loquor1 to speak74 ,a modification of natural speech by which the voice is made to appear to come from a distance4 ,the ancients supposed that the voice was formed in the belly2 hence the name4 ,,ven,,tri-,,cles of the heart4 ,the two largest cavities of the heart1 situated at its apex or point4 ,,ver,,te-,,bral ,,column 7,l4 vertebra1 a joint74 ,the back-bone1 consisting of twenty-four separate bones1 called vertebr1 firmly jointed together2 also called the spinal column and spine4 ,,ves,,ti-,,bule4 ,a portion of the internal ear1 communicating with the semicircular canals and the cochlea2 so called from its fancied resemblance to the vestibule or porch of a house4 ,,vil,,li 7,l4 villus1 the nap of cloth74 ,minute thread-like projections found upon the internal surface of the small intestine1 giving it a velvety appearance4 ,,vit,,re-,,ous 7,l4 vitrum1 glass74 ,having the appearance of glass2 applied to the humor occupying the largest part of the cavity of the eyeball4 ,,viv-,i-,,sec,,tion 7,l4 vivus1 alive1 and seco1 to cut74 ,the practice of operating upon living animals1 for the purpose of studying some physiological process4 ,,vocal ,,cords4 ,two elastic bands or ridges situated in the larynx2 they are the essential parts of the organs of the voice4 99 99 99 99 99 #bfe ,,index4 ------o------ ,a4 ,,page ,absorbent vessels1 #ig ,absorption1 #if by blood-vessels1 #if by the lacteals1 #if of the food1 #if ,accommodation1 function of1 #bac ,achilles1 tendon of1 #bg ,adam's apple1 #bbi ,air1 atmospheric1 #aca ,changes in1 in respiration1 #acb ,carbonic acid in1 #ach ,composition of1 #aca ,dust in the1 #acg ,effects of impure1 #aci ,impurities in1 #acf ,matters in the expired1 #acb ,provision for purifying1 #ada ,renovation by ventilation1 #adb ,air-cells of the lungs1 #abe ,air-passages1 #abe ,albinos1 #dd ,albumen1 #eh of the blood1 #ajb ,albuminoid substance1 #eg ,varieties of1 #eg ,properties of1 #eg-eh ,albuminose1 #id ,alcoholic liquors1 #gg ,physiological action of1 #gh ,alimentary canal1 #ha ,animal functions1 #adc ,animal heat1 #adc how produced1 #adc regulated by perspiration1 #ade ,animals1 relative strength of1 #bh ,apoplexy1 #aga ,aqueous humor1 #baj ,arachnoid membrane1 #aeb ,arbor vit1 #aed ,arterial blood1 #ajg-ace differs from venous1 #ace ,arteries1 #aad ,arrangement of1 #aae ,carotid1 #aaf ,distribution of1 #aae ,pulsation of1 #aae ,radial1 #aaf ,temporal1 #aaf ,arytenoid cartilage1 #bbi ,asphyxia1 #bej ,assimilation1 #hj1 #aba ,audition1 #bae ,auditory canal1 #bah nerve1 #bbb ,auricles of the heart1 #aji ,b4 ,back-bone1 #ba ,bathing1 #dg ,importance of1 #dg ,time and manner of1 #di ,baths1 #dh ,different kinds of1 #dh ,belladonna1 #bjf dilates the pupil1 #bjf ,use as a cosmetic1 #bjf ,bile1 #ie ,secretion of1 in the liver1 #ie ,accumulation of1 in the gall-bladder1 #ie ,uses of1 #ie ,biliary duct1 #ie ,bladder1 ,gall-1 #ie ,bleeding1 how stopped1 #aba ,blind-spot1 #bjg ,blood1 #aja ,arterial1 #ajg-ace ,change of color1 #ajg ,circulation of1 #ajg1 #acc ,coagulation of1 #aje ,composition of1 #ajb corpuscles1 #ajb1 #ajc fluid1 #aje ,microscopic appearance of1 #ajb ,respiratory changes in1 #acc ,uses of the1 #aje ,venous1 #ajg1 #ace ,blood-vessels1 #aad1 #aah ,absorption by1 #if ,injuries to the1 #aba ,body1 renovation of the1 #ff ,bones1 #ae ,form and composition of1 #af ,growth of1 #bb ,microscopic structure of1 #ag ,repair of1 #bc ,structure of1 #ag ,uses of1 #ae ,bowels1 #id ,brain1 #aej ,anatomical structure of1 #aeb ,function of the1 #agb ,injuries of the1 #agc ,membranes of the1 #aeb ,reflex action of the1 #agd #bff ,bread1 #gb ,bronchial tubes1 #abe ,bronchitis1 #abh ,c4 ,canals1 ,semicircular1 #bbc ,capillary blood-vessels1 #aah ,circulation in the1 #aah ,carbonic acid1 #acb exhaled from the lungs1 #acb in the air1 #ach retention in the blood1 #acd ,cartilage1 #bj ,arytenoid1 #bbi ,cricoid1 #bbi ,thyroid1 #bbi ,casein1 #eh ,cataract1 #baj ,cells1 ,nerve1 #aej1 #aei ,ciliated1 #abh ,cerebellum1 #aec ,function of the1 #agb ,cerebro-spinal nervous system1 #aej ,cerebrum1 #aeb ,function of the1 #agb ,cheese1 #eh ,chest1 ,framework of1 #ai ,contents of the1 #ai ,chocolate1 #gg ,chorea1 #afi ,choroid coat of the eye1 #bjd ,chyle1 #ie ,chyme1 #id ,cilia1 #abh ,circulation1 #ajg in the frog's foot1 #aai of the blood1 #ajg ,rapidity of1 #abj through the heart1 #aab through the lungs1 #abc ,clothing1 #ea ,coagulation of milk1 #eh of the blood1 #ajd ,cochlea1 #bbc ,coffee1 #ge ,effects of1 #ge1 #gf ,collar-bone1 #ai ,color-blindness1 #bji ,column1 ,spinal1 #ba ,combustion1 ,spontaneous1 #ade ,complexion1 #dd ,concha of the ear1 #bag ,conjunctiva1 #bjj ,contraction of heart1 #aaa of muscles1 #bg ,convulsions1 #afi ,cooking1 #gj ,cords1 ,vocal1 #abf1 #bcj ,cornea1 #bjc ,corpuscles1 ,blood1 #ajb ,cosmetics1 #ea ,cranial ganglia1 #aej ,functions of1 #aga ,cranial nerves1 #aed ,cranium1 #ai ,cricoid cartilage1 #bbi ,crystalline lens1 #bji ,uses of1 #baj ,cuticle1 #da ,function of1 #ahc ,cutis1 #db ,d4 ,decussation of motor and sensory fibres of spinal cord1 #afd ,dentition of infancy1 #hb ,diaphragm1 ,movements of the1 in respiration1 #abh1 #abi ,diastole of the heart1 #aaa ,diet1 ,mixed1 #ff1 #he ,necessity for changing1 #fg ,necessity of a regulated1 #fb ,the best1 #fc ,digestion1 #hj ,circumstances affecting1 #ig ,gastric1 #ic ,intestinal1 #id ,nature of1 #ha ,organs of1 #ha-ia ,drowning1 #bej ,duct1 ,biliary1 #ie ,nasal1 #bja ,pancreatic1 #ie ,thoracic1 #ig ,dura ,mater1 #aeb ,e4 ,ear1 #bag ,external1 #bag ,internal1 #bbb ,middle1 #bai ,foreign bodies in1 #bbe ,drum of the1 #bai ,bones of the1 #bbj ,ear-sand1 #bbc ,ear-stones1 #bbc ,ear-wax1 #bai ,eggs1 #fh ,composition of1 #fh ,emulsion of fats1 in digestion1 #ie ,enamel of the teeth1 #hb ,epiglottis1 #abf1 #bbi ,uses of1 #abf1 #bbj ,eustachian tube1 #bba ,exercise1 #cj ,different modes of1 #ca ,effects of1 #cj ,importance of1 #cj ,open-air1 #cc ,expiration1 #abh ,movements of1 #abi ,extensor muscles1 #bf ,eye1 #aih ,eyeball1 #bjc ,eyelashes1 #bjj ,eyelids1 #bjj ,f4 ,fats1 #ei ,emulsion of1 #ei ,source of1 in food1 #ei ,fenestra ovalis1 #bbd ,fibres1 ,muscular1 #be #bfg ,fibres1 ,nervous1 #adi ,fibrine in food1 #eh of the blood1 #ajb ,fish1 as food1 #ga ,flexor muscles1 #bf ,food1 #ec ,animal1 #fg ,daily quantity of1 #fe ,ingredients of1 #ed-fb ,necessity for1 #fd ,source of1 #ec ,vegetable1 #ga ,g4 ,gall-bladder1 #ie ,ganglia1 cranial1 ,functions of the1 #aga ,gases1 ,interchange of1 in the lungs1 #acd ,gastric digestion1 #ic ,gastric juice1 #ia ,action of1 #ic ,daily quantity of1 #ib ,general sensibility1 #agi ,glands1 ,perspiratory1 #de ,salivary1 #hf ,sebaceous1 #dd ,glossary1 #beb ,glosso-pharyngeal nerve1 #ahi ,gullet1 #ij ,gum1 #fa as food1 #fb ,gustatory nerve1 #ahi ,gymnastics1 #cc-ch for schools and colleges1 #cc ,h4 ,hair1 #db ,uses of1 #dd ,hearing1 ,sense of1 #bae ,protection of1 #bbd ,heart1 #ajg ,cavities of the1 #aji1 #aaj ,circulation through the1 #aab ,frequency of action1 #aab ,movements of the1 #aaa ,valves of the1 #aab ,heat1 ,animal1 #adc ,production of1 #adc ,regulation of1 #ade ,hemiplegia1 #afe ,humor1 ,aqueous1 #baj ,crystalline1 #bji ,vitreous1 #baj ,hunger1 #fe ,seat of the sensation of1 #fe ,hydra1 #adi ,hydrophobia1 #afi ,hygiene1 #ac ,hyperopia1 #bab ,i4 ,incus1 #bbj ,inorganic substances in food1 #ed ,insalivation1 #hf1 #hh ,insensible perspiration1 #df ,inspiration1 #abh ,intestinal juice1 #ie ,action of1 #if ,intestines1 #id ,complete digestion in the small1 #id ,villi of the1 #if ,iris1 #bje ,function of1 #bje ,iron1 #ef ,proportion in the blood1 #eg ,proportion in the food1 #eg ,j4 ,joints1 #ai ,varieties of1 #bj ,juice1 gastric1 #ia ,intestinal1 #ie ,pancreatic1 #ie ,l4 ,labyrinth1 #bbb ,lachrymal canals1 #bja gland1 #bja ,lacteals1 #if ,absorption by1 #if ,lactic acid in gastric juice1 #ib ,lactometer1 #fh ,large intestines1 #id ,laryngoscope1 #bca ,larynx1 #abe1 #bbh ,production of the voice in the1 #abf1 #bbh ,lens1 crystalline1 #bji ,ligaments1 #ai ,light1 theory of1 #aig ,lime in the bones1 #af in the food1 #ef ,importance of1 #ef ,liver1 #ie ,secretion of the1 #ie ,locked jaw1 #afi ,long-sight1 #bab ,lungs1 #abc ,capacity of1 #acj ,structure of1 #abe ,lymph1 #ig ,lymphatic vessels1 #ig ,m4 ,magendie1 on pain1 #aha ,magnesia1 ,compounds of1 in food1 #eg ,malleus1 #bbj ,marrow of the bones1 #ag ,mastication1 #hb ,importance of1 #hh1 #hi ,meats1 #fh ,the cooking of1 #fi ,the preservation of1 #fi ,membrane of the tympanum1 #bai ,medulla oblongata1 #aed ,function of the1 #aga ,microscope1 #bcf ,the value of the1 #bcf ,simple1 #bcg ,compound1 #bci ,the use of the1 #bci #bfh ,milk1 #fh ,composition of1 #fh ,specific gravity of1 #fh ,milk-teeth1 #hb ,mucous membrane of air passages1 #abg ,muscles1 #be ,function of the1 #be ,flexion and extension of1 #bf ,voluntary and involuntary1 #bf ,muscular contraction1 #bg fibres1 #be sense1 #ahh ,myopia #bab ,n4 ,nails1 #db ,uses of the1 #dd ,nasal cavities1 #aib duct1 #bja ,nerve1 ,auditory1 #bbb ,glossopharyngeal1 #ahi ,gustatory1 #ahi ,olfactory1 #aic ,optic1 #aig ,sympathetic1 #aeh ,nerve cells1 #aej1 #aei ,nerve fibres1 #adi ,nerves1 ,cranial1 #aed ,spinal1 #aef ,functions of the1 #afj ,sensory1 functions of the1 #afj ,motor1 functions of the1 #afj ,sympathetic system of1 #aeh ,nervous system1 #adh1 #adi ,cerebro-spinal1 #aej ,nervous tissue1 ,properties of1 #aei ,nose1 #aib ,nutrition1 ,processes of1 #hj ,o4 ,oesophagus1 #ij ,oil1 ,sources of1 in food1 #ei ,old-sight1 #bae ,olfactory nerve1 #aic ,optic nerve1 #aig ,orbicular bone1 #bbj ,orbit of the eye1 #aii ,organic substances as food1 #eg-fb ,organs of circulation1 #ajg ,digestion1 #ha-ia ,respiration1 #abc ,sight1 #aih ,voice1 #bbh ,oxygen1 #aca ,amount of1 consumed in respiration1 #acb ,continually supplied to the atmosphere1 #ada ,p4 ,pain1 ,relations of1 to pleasure1 #aha ,sensation of1 #ahj ,uses of1 #ahj ,pancreatic juice1 #ie ,uses of1 #ie ,pancreatin1 #ie ,paraplegia1 #afc ,parlor gymnasium1 #cf ,passages1 ,air1 #abe ,pelvis1 #ai ,pepsin1 #ib ,peristaltic action of the stomach1 #ib ,peritoneum1 #id ,perspiration1 ,daily amount of1 #df ,sensible and insensible1 #df ,uses of1 #df1 #ade ,perspiratory glands1 #de ,physical strength1 #bi ,culture1 #cc ,physiology1 #aa ,animal1 #aa ,comparative1 #aa ,human1 #aa ,vegetable1 #aa ,pia mater1 #aeb ,plasma of the blood1 #ajb ,pleura1 #abd ,pleurisy1 #abh ,pneumo gastric nerve1 #aga ,pneumonia1 #abh ,poisons and their antidotes1 #bdg ,potash in the blood1 #eg ,potato1 #gc ,presbyopia1 #bae ,preservation of the teeth1 #he ,ptyalin1 #hh ,pulsation of the heart1 #aac of the arteries1 #aaf ,pulse1 #aae ,form of the1 #aaf ,writer1 #aaf ,pylorus1 #ij ,r4 ,radial artery1 #aaf ,red corpuscles of the blood1 #ajb ,reflex action of the spinal cord1 #afe ,requisites for1 #afg ,uses of1 #afg1 #agj ,causing convulsions1 #afi ,objects of1 #agj of the brain1 #agd1 #age ,rennet1 #eh ,respiration1 #abc ,change of blood in1 #abc-acc ,frequency of1 #abi ,movements of1 #abh ,object of1 #abc ,organs of1 #abc ,respiratory labor1 #ace ,rest1 necessity for1 #ch ,retina1 #bjf ,retinal light1 #bjg ,ribs1 ,movements of1 in respiration1 #abh ,s4 ,saccharine substances1 #fj ,saliva1 #hf ,importance of1 #hh ,secretion of1 #hf ,salivary glands1 #hf1 #hg #bfi ,salt1 ,common1 #ee ,importance of1 #ef ,sclerotic coat of the eyeball1 #bjd ,sebaceous glands1 #dd ,secretion of1 #de ,semicircular canals1 #bbc ,sensation of pain1 #ahj ,relations of1 to pleasure1 #aha of temperature1 #ahg of weight1 #ahh ,modification of1 #agh ,production of1 #agg ,variety of1 #agh ,sense of hearing1 #bae sight1 #aif smell1 #aib taste1 #ahi touch1 #ahd ,sense1 muscular1 #ahh thermal1 #ahg ,senses1 ,special1 #agg ,sensibility1 ,general1 #agi ,short-sight1 #bab ,sinews1 #bg ,sight1 ,sense of1 #aif ,organs of1 #aih ,skeleton1 #ai ,skin1 #da ,structure of1 #da ,skull1 #ai ,uses of the1 #ai ,sleep1 ,necessity for1 #ch ,amount required1 #ci ,small intestines1 #id ,smell1 ,sense of1 #aib ,nerve of1 #aic ,uses of1 #aid ,soda in the food1 #eg ,sound1 ,production of1 #bae ,special senses1 #agg ,spectroscope1 #ajd ,speech1 #bbg ,relation of1 to the sense of hearing1 #bbh ,sphygmograph1 #aaf ,spinal column1 #ba ,spinal cord1 #aee ,decussation of the1 #afd ,direction of fibres in1 #afd ,functions of the1 #afb ,nerves of1 #aef ,reflex action of1 #afe ,spontaneous combustion1 #ade ,stapes1 #bbj ,starch1 #fa ,its change into sugar1 #fa ,different kinds1 #fa ,effect of boiling1 #fa ,microscopic appearance1 #fa ,stimulating substances1 #fb ,stomach1 #ij1 #ib ,digestion1 #ic ,movements of1 #ib ,secretion of1 #ib ,st4 ,vitus' dance1 #afi ,sugar1 #fj ,varieties1 #fj ,sources of1 #fa ,sun-bath1 #ej ,sympathetic system of nerves1 #aeh ,synovia1 #bj ,systole of the heart1 #aaa ,t4 ,taste1 ,association of1 #aij ,education of1 #aia ,organ of1 #ahh ,sense of1 #ahi ,tea1 ,effect of1 #gf ,kinds of1 #gf ,tears1 #bja ,escape of the1 #bja ,teeth1 #hb ,temporary set of1 #hb ,permanent set of1 #hc ,bicuspid1 #hc ,canine1 #hc ,incisor1 #hc ,molar1 #hd ,arrangement of1 #he of different animals1 #he ,preservation of1 #he ,temperature of the body1 #adf ,extremes of1 #adf ,sensations of1 #ahg ,tendon of ,achilles1 #bg ,tendons1 #bg ,tetanus1 #afi ,thermal1 #ej ,therm sense1 #ahg ,thirst1 #fe ,thoracic duct1 #ig ,thorax1 #ai ,thyroid cartilage1 #bbi ,tissues1 intimate structure of the1 #bcf ,human1 #bdd of the lower animals1 #bde ,tongue1 #ahh ,nerves of1 #ahi ,sensibility1 #ahi ,touch1 ,delicacy of1 #ahf ,organs of1 #ahc ,sense of1 #ahd ,trachea1 #abe ,transfusion1 #ajf ,trichina spiralis1 #ga ,trunk1 #ai ,tympanum of the ear1 #bai ,membrane of1 #bai ,v4 ,valves of the heart1 #aab of the veins1 #aag ,vapor1 ,animal1 in breath1 #acb ,vegetable food1 #ga ,vegetative functions1 #adh ,veins1 #aag ,valves of1 #aag ,venous blood1 #ace ,changes of1 in respiration1 #acc ,ventilation1 #adb ,ventricles of the larynx1 #bbi of the heart1 #aaj ,ventriloquism1 #bce #bgj ,vertebrae1 #ba ,vestibule of the internal ear1 #bbc ,villi of the intestines1 #if ,absorption by1 #if ,vital knot1 #aga ,vitreous humor1 #baj ,vocal cords1 #abf1 #bcj ,observation of1 with laryngoscope1 #bca ,voice1 #bbg ,organ of1 #bbh ,production of1 #bcb ,varieties of1 #bcc ,w4 ,water1 #gd ,action of1 on lead1 #ge ,chemically pure1 #gd ,croton1 #gd exhaled with the breath1 #acb from springs and wells1 #gd ,proportion of1 in the blood #ee of1 in the tissues and fluids of the body1 #ed ,ridgewood1 #gd ,walking1 as a means of exercise1 #ca ,white corpuscles of the blood1 #ajd ,wisdom teeth1 #hd 99 99 99 99 99 ,changes made to printed original ,page #de1 ,sect4 #ab4 7#d1 ,fig4 #ad73 '7#d1 ,fig4 #ac7' in original4 ,page #bj1 ,sect4 #bj1 note4 philosophy3 'philosphy' in original4 ,page #aja1 heading4 ,sphygmograph3 ',spygmograph' in original4 ,so also in ,table of ,contents1 but cf4 p4 #aaf and ,index4 ,page #add1 ,sect4 #df1 note4 zoologists3 'zooligsts' in original4 ,page #aii1 ,sect4 #ec4 considerable3 'considera-ale' 7on line break7 in original4 ,page #bee1 s4v4 ,convolutions4 external3 'extenal' in original4