,transcriber's ,note3 ,italic text is denoted by underscores and bold text by tildes4 ,,fur ,,dyeing ,,and ,,fur ,,dressing ,,principles ,,and ,,practice ,,of ,,fur ,,dressing ,,and ,,fur ,,dyeing ,,by ,,william ,e4 ,,austin1 ,b4,s4 ,,consulting ,,chemist ,,to ,,the ,,fur ,,industry ,,illustrated ,illustration ,,new ,,york ,d4 ,,van ,,nostrand ,,company ,,eight ,,warren ,,street #aibb ,copyright1 #aibb1 by ,d4 ,,van ,,nostrand ,,company ,all rights reserved1 including that of translation into foreign languages1 including the ,scandinavian ,,printed ,,in ,,the ,,united ,,states ,,of ,,america ,,preface ,the great increase in the use of furs during the past few decades has caused the fur dressing and dyeing industry to rise from relative insignificance to considerable importance as a branch of applied chemistry4 ,the past eight years1 moreover1 have witnessed the virtual transference of the leadership in the dressing and dyeing of furs from ,europe to ,america1 and in the quality and variety of products1 the domestic industry is now in every way the equal of1 and in many respects superior to the foreign4 ,the great bulk of ,american furs which formerly were sent to ,leipzig1 ,paris or ,london to be dressed and dyed1 are now being dressed and dyed in this country4 ,in spite of these facts1 very little is generally known about the nature and manner of the work constituting the dressing and dyeing of furs4 ,even among members of other branches of the fur trade1 there is very little accurate information on the subject4 ,real knowledge concerning fur dressing and dyeing is possessed only by those actually engaged in the industry4 ,the interest and efforts of scientists and technologists have been enlisted to only a small extent in the technical development of the industry4 ,the reason for this may be attributed to two related causes3 first1 the almost monastic seclusion in which fur dressers and dyers1 particularly the latter1 conducted their operations1 and even to-day the heavy cloud of mystery is being dispelled but very slowly2 and second1 as a consequence of the first1 the lack of any reliable literature on the subject4 ,of the few books which have been written on the industry of fur dressing and fur dyeing 7all of them either ,german or ,french71 most are hopelessly out of date1 or contain no trustworthy data2 or1 if they do have real merit1 they cannot be obtained4 ,numerous articles in the technical journals are of interest1 but they contain very little information of value4 ,this work is intended for a two-fold purpose3 first1 that it may serve as a text-book for those who expect to make fur dressing and dyeing their vocation4 ,the fundamental principles upon which the industry is based are discussed in the light of the most recent chemical and technical developments1 and the most important operations are treated fully and systematically1 and are illustrated with practical examples4 ,secondly1 as a practical handbook for the worker in the fur dressing and dyeing plant4 ,the latest factory processes and methods are described1 and numerous working formulas given4 ,the formulas are all such as have been successfully used on a large scale1 and give satisfactory results when applied under the proper conditions4 ,in addition1 it is believed that the book will prove of interest to chemists and other students of industrial chemistry1 since it will be an introduction into a field of applied chemistry1 about which very little is known to those outside of the industry4 ,thanks are due to ,dr4 ,l4 ,a4 ,hausman1 of ,cornell ,university1 for material used in ,chapter ,,ii2 to ,dr4 ,e4 ,lesser of the ,american ,dyewood ,company1 for information and assistance on the subject of ,vegetable ,dyes2 to the ,gaskill ,chemical ,corp41 ,american ,aniline ,products1 ,inc41 the ,cassella ,company1 and the ,franklin ,import ,export ,co41 for information about their products in connection with the chapter on ,oxidation ,colors2 to ,f4 ,blattner1 ,fletcher ,works1 ,inc41 ,s4 ,m4 ,jacoby ,co41 ,proctor ,schwartz1 ,inc41 ,reliable ,machine ,works1 ,seneca ,machine ,tool ,co41 ,inc41 and the ,turner ,tanning ,machinery ,co41 for the use of the cuts of the various machines4 ,,william ,e4 ,,austin4 ,,new ,,york1 ,may1 #aibb4 ,,table ,,of ,,contents ,,chapter ,,page ,,preface ,i4 ,,furs ,,and ,,their ,,characteristics #a ,introductory4 ,knowledge of furs essential4 ,definitions4 ,differences in furs of various animals4 ,effect of climate on furs4 ,effect of age and season on furs4 ,durability and relative weights of furs4 ,description of important furs4 ,,ii4 ,,structure ,,of ,,fur #ba ,the skin4 ,the hair4 ,under-hair and top-hair4 ,chemical composition of furs4 ,action of chemicals on the skin4 ,action of chemicals on the hair4 ,,iii4 ,,fur ,,dressing3 ,,introductory ,,and ,,historical #bi ,objects of fur dressing4 ,origin of fur dressing4 ,use of fats4 ,use of salt and alum4 ,use of the tannins4 ,early organizations of the fur workers4 ,modern organizations of the fur dressing industry4 ,,iv4 ,,fur ,,dressing3 ,,preliminary ,,operations #cf ,flat skins and cased skins4 ,herbivorous and carnivorous fur animals4 ,beaming or scraping4 ,softening the skins4 ,cleaning2 hydro-extracting4 ,fleshing4 ,v4 ,,fur ,,dressing3 ,,tanning ,,methods #de ,nature of the tanning process4 ,chief tanning methods4 ,comparison of the tanning methods4 ,effect of dyeing operations on the dressing4 ,,vi4 ,,fur ,,dressing3 ,,drying ,,and ,,finishing #ga ,importance of the drying process4 ,methods of drying4 ,a modern type of drying device4 ,oiling4 ,staking or stretching4 ,beating and combing4 ,drum-cleaning4 ,unhairing and shearing4 ,,vii4 ,,water ,,in ,,fur ,,dressing ,,and ,,dyeing #he ,importance of water in dressing and dyeing4 ,water suitable for dressing and dyeing4 ,soft water and hard water4 ,effects of hardness in water4 ,,viii4 ,,fur ,,dyeing3 ,,introductory ,,and ,,historical #ij ,purposes of fur dyeing4 ,improvement of furs faulty in color4 ,production of a uniform shade on furs4 ,dyeing furs to obtain novel effects4 ,imitation of valuable furs on cheaper skins4 ,difficulties due to the hair4 ,difficulties due to the leather4 ,,ix4 ,,fur ,,dyeing3 ,,general ,,methods #ih ,two methods of dyeing furs4 ,development of the dyeing methods4 ,the brush process4 ,the dip process4 ,blending4 ,drying and finishing the dyed furs4 ,x4 ,,fur ,,dyeing3 ,,killing ,,the ,,furs #ajf ,nature of the killing process4 ,old killing formulas4 ,modern killing agents4 ,procedure of killing4 ,killing with soda4 ,killing with lime4 ,killing with caustic soda4 ,,xi4 ,,fur ,,dyeing3 ,,mordants #aad ,nature of mordanting4 ,purposes of mordanting4 ,theory of mordants4 ,procedure of mordanting4 ,aluminum mordants4 ,iron mordants4 ,copper mordants4 ,chromium mordants4 ,tin mordants4 ,alkaline mordants4 ,,xii4 ,,fur ,,dyeing3 ,,mineral ,,colors ,,used ,,on ,,furs #abe ,mineral chemicals as fur dyes4 ,lead dyes4 ,potassium permanganate as a dye4 ,other mineral dyes4 ,,xiii4 ,,fur ,,dyeing3 ,,vegetable ,,dyes #abh ,wood dyes4 ,old dye formulas4 ,the vegetable dye materials4 ,the tannin substances4 ,logwood4 ,fustic4 ,brazilwood4 ,other vegetable dyes4 ,characteristics of the wood dyes4 ,application of the vegetable dyes4 ,application by the brush process4 ,application by the dip process4 ,production of shades other than black4 ,,xiv4 ,,fur ,,dyeing3 ,,aniline ,,black #add ,dyeing of seal4 ,nature and history of ,aniline ,black4 ,chemistry of the ,aniline ,black process4 ,three stages in the formation of ,aniline ,black4 ,methods of applying ,aniline ,black4 ,one-bath ,aniline ,black4 ,oxidation ,aniline ,black4 ,diphenyl ,black4 ,aniline ,black by ,green's process4 ,aniline ,black by the dip method4 ,,xv4 ,,fur ,,dyeing3 ,,oxidation ,,colors #aee ,the original patents4 ,the first ,oxidation fur dyes4 ,early difficulties4 ,solution of the difficulties4 ,progress with the ,oxidation dyes4 ,para-phenylene-diamine3 a typical ,oxidation color4 ,range of shades obtainable4 ,mordants4 ,procedure in dyeing4 ,typical formulas4 ,combination of ,oxidation colors with other dyes4 ,,xvi4 ,,fur ,,dyeing3 ,,coal ,,tar ,,dyes #aga ,use of coal tar dyes4 ,basic colors4 ,acid colors2 dyeing at higher temperatures4 ,chrome colors4 ,vat dyes4 ,,xvii4 ,,bleaching ,,of ,,furs #agi ,purpose of bleaching4 ,steps in the bleaching process4 ,methods of bleaching4 ,bleaching materials with reducing action4 ,bleaching materials with oxidizing action4 ,blueing4 ,,bibliography #ahe ,,fur ,,dressing ,,and ,,fur ,,dyeing ,,chapter ,i ,,furs ,,and ,,their ,,characteristics ,furs have in general two uses3 as the goods which constitute the basis of the furrier's art1 and as the source of material for the hat manufacturer4 ,in the latter case1 only the hair part of the fur is utilized in the hat trade for the production of felt1 the skin being either made into leather1 or used as the raw material for making high-grade glue and gelatine4 ,it is the furrier1 therefore1 who uses the great bulk of furs1 and requires them to be dressed and dyed4 ,in discussing the dressing and the dyeing of furs1 there are1 broadly speaking1 two fundamental subjects to be considered3 first1 the raw materials employed1 which are1 of course1 the skins or pelts as they come from the trapper4 7,other substances used in fur dressing and dyeing are accessories1 and will be studied in connection with the processes47 ,second1 all those operations1 physical and chemical1 manual and mechanical1 to which the raw skins have to be subjected in order to obtain the finished fur1 ready for use by the furrier4 ,next to the inherent qualities of the fur skin1 the future value of a fur in a manufactured garment depends largely on the dressing and dyeing it receives4 ,it is in these operations that the beauty of the fur can be brought out to its fullest degree1 and if possible1 enhanced1 or the attractive features can be marred or destroyed1 and the fur rendered quite worthless4 ,therefore1 it is quite essential for the fur dresser and the fur dyer in addition to the technical knowledge and experience which are the fundamental requisites of the industry1 also to have more than a superficial familiarity with the various kinds of furs4 ,in fact1 an accurate knowledge of the nature and chief characteristics of furs in general1 and of the individual classes1 in particular1 is almost indispensable to obtain the best results4 ,the habits and habitats of the various fur-bearing animals are factors which largely determine the constitution of the fur1 and the nature of the skin4 ,there are as many different kinds of fur hair1 with as many different kinds of skin bearing the hair1 as there are classes of furs4 ,the methods of dressing1 and often1 if the furs are to be dyed1 the manner of dyeing1 are determined by the nature of these component parts of furs4 ,various chemicals affect furs in widely different ways4 ,the divergence with regard to the physical and chemical properties of the classes of furs is such as to make almost imperative a detailed knowledge of the typical members of the many groups of commercial furs4 ,to be sure1 there are many engaged in the dressing and dyeing of furs1 who never made a formal study of this phase of the industry1 but acquired their knowledge empirically1 and are apparently quite successful4 ,it must not be denied1 that practise and experience1 as in every field of enterprise1 are essential to obtaining the best results4 ,but the time and cost of acquiring this precious experience can be considerably reduced by systematically studying the important characteristics and properties of furs4 ,these will be treated briefly1 but in sufficient detail to form a basis for discussing the operations of dressing and dyeing4 ,fur-bearing animals are mammals whose skins are used in the manufacture of fur garments and other fur wearing apparel4 ,the skin1 when it is removed from the animal is called a pelt1 or sometimes1 in the case of large animals1 a hide4 ,the pelt1 after having been dressed and dyed1 is called a fur1 the skin part being referred to as the leather1 and the hair as the pelage4 ,however1 this terminology is not strictly adhered to in practise1 and the various terms are often employed interchangeably4 ,the various fur-bearing animals differ considerably in the characteristics of the furs they yield4 ,with few exceptions1 notably beaver and ,alaska red fox1 the depth of shade increases as the habitat of the animal species is nearer the equatorial regions4 ,there seems to be a direct relationship between the intensity of color of the pelt1 and the distance from1 or proximity to the polar1 or the torrid regions4 ,thus1 white mammals1 such as polar bear1 ermine1 white or ,siberian hare1 are found only in the northern lands4 ,an exception is the sheep1 which1 due to its domestic nature1 can be found in almost all parts of the civilized world4 ,tropical animals on transportation to colder climates1 have been known to become lighter-haired when adapted to their new environment4 ,the skins of animals living in dense woods or forests1 are generally of a deeper color than in animals living in more open territory4 ,as a general rule1 fur-bearing animals have darker hair on the back than on the sides and belly4 ,the badger1 hamster1 ratel and panda are exceptions having the darker hair on the belly and sides1 and the lighter hair on the back4 ,with regard to the intensity of color1 the skunk has the blackest fur1 although some domestic cats are also quite black4 ,other animals whose fur is nearly black1 are the black bear1 and the black fox1 which is a variety of the silver fox1 but the color is often of a brownish shade4 ,the colors which predominate among animals of the fur-bearing variety1 are white1 black1 brown1 and grey4 ,less common are yellow shades1 and those known as blue4 ,the quality of the fur on all mammals improves with cold1 and animals living at greater altitudes1 with correspondingly lower temperatures1 have thicker and finer hair than those living nearer sea-level4 ,a cold winter generally produces fur of high quality and fine color1 a mild winter may cause the hair to be inferior4 ,in all climates1 animals found in dense woods1 have fur which is deeper1 silkier1 thicker1 and glossier than that of animals living in the open4 ,animals inhabiting inland lakes and rivers1 have finer and softer hair than those living near the coast or land exposed to sea winds4 ,in general1 the hair of animals of the cold regions is short1 fine1 soft1 and downy1 while the hair of animals of warmer lands1 is longer1 stiffer1 and harder4 ,both the quality and color of the fur vary with the age of the animal4 ,the young usually have a thicker coat of fur than adults1 but the hair is too soft1 and the skin generally too tender to be fit for use4 ,in certain cases1 particularly the baby lambs1 very young skins are especially prized1 and eagerly sought1 but extraordinary care has to be exercised in working with them4 ,fur is at its best when the animal is between one and two years old4 ,after this age1 the fur becomes coarse and scraggy4 ,the animal attains its fullest growth of hair usually in the height of winter1 and the fur is best between then and very early spring4 ,before mid-winter the hair is short and thin1 and in the spring it begins to shed1 and will continue to fall out even in the dressed fur4 ,the color of the hair also becomes lighter with age1 and the new growth which generally comes in the fall is darker than the old coat4 ,different members of the same species1 will1 other factors such as age and season being equal1 vary as to color and quality4 ,there may even be several different color phases of the same species of animal1 such as the cross fox and the silver fox1 both of which are of the same genus as the red fox2 black muskrats are of the same class as the brown variety1 etc4 ,the individual pelt likewise presents many variations in color and nature of the hair4 ,in some parts1 the hair is thicker and softer than others1 and the color varies in intensity and shade throughout the different sections of the skin4 ,furs do not have differences confined to the hair part only2 the leather also presents considerable variation among the different fur-bearing animals1 especially in regard to the weight and thickness4 ,the durability of furs1 relatively considered under similar conditions of wear1 also varies widely4 ,in the following table the relative durability of dressed furs1 and in certain instances also dyed furs1 otter being taken as standard1 is given1 as well as the weight in ounces per square foot of skin of these furs4 ,name of ,fur ,durability ,wt4 in oz4 ,otter #ajj per sq4 ft4 ,astrachan #aj #c ,bear1 brown or black #id #g ,beaver1 natural #ij #d ,beaver1 plucked #he #c-g_/h ,chinchilla #ae #a-a_/b ,civet cat #dj #b-c_/d ,coney #bj #c ,ermine #be #a-a_/d ,fox1 natural #dj #c ,fox1 dyed black #be #c ,genet #ce #b-c_/d ,goat #ae #d-a_/h ,hare #je #b-a_/d ,krimmer #fj #c ,kolinsky #be #c ,leopard #ge #d ,lynx #be #b-c_/d ,marten1 ,baum natural #fe #b-c_/d ,marten1 ,baum blended #de #b-c_/d ,marten1 ,stone natural #de #b-g_/h ,marten1 ,stone dyed #ce #b-g_/h ,mink1 natural #gj #c-a_/d ,mink1 dyed #ce #c-a_/d ,mink1 ,jap #bj #c ,mole #jg #a-c_/d ,muskrat #de #c-a_/d ,nutria1 plucked #be #c-a_/d ,opossum1 natural #cg #c ,opossum1 dyed #bj #c ,opossum1 ,australian #dj #c-a_/b ,otter1 land #ajj #d-a_/b ,otter1 sea #ajj #d-a_/b ,persian lamb #fe #c-a_/d ,pony1 ,russian #ce #c-a_/b ,rabbit #je #b-a_/d ,raccoon1 natural #fe #b-a_/d ,raccoon1 dyed #ej #b-a_/b ,sable #fj #b-a_/b ,sable1 blended #de #b-a_/b ,seal1 fur #hj #c-a_/b ,seal1 fur dyed #gj #c-a_/h ,skunk1 tipped #ej #b-g_/h ,squirrel1 grey #bj-be #a-c_/d ,wolf1 natural #ej #f-a_/b ,wolverine #ajj #g ,in estimating the value of a fur1 many factors have to be considered4 ,there is no one standard by which the skins are judged1 each kind of fur having its own criterion4 ,however1 the general points by which raw furs are graded are1 color1 size1 origin1 quality and quantity of hair1 condition of leather1 date or season of trapping1 methods of handling1 etc4 ,beaver1 for example1 is graded as large1 medium1 small and cubs4 ,red foxes1 first1 into ,alaska1 ,labrador1 and ,nova ,scotia1 and then these divisions are classed as large1 medium and small4 ,skunks are graded according to the amount of white on the skin1 the less white1 the more valuable the fur4 ,the qualities which make a fur desired depend first of all on the nature of the fur itself4 ,pretty color1 luster1 thickness1 softness1 length1 uniformity and regular fall of the hair are the chief points to be considered4 ,while the leather part of the fur is of secondary importance in the evaluation of a fur1 it must possess strength1 lightness of weight1 and when properly dressed1 should be supple and have a certain firmness or #8feel4' ,the abundance or scarcity of a fur-bearing animal also determines the value of the fur4 ,furs which are always comparatively rare1 such as silver fox1 ,russian sable1 chinchilla1 etc41 are always highly prized4 ,in this connection1 circumstances which tend to decrease the number of available pelts of any particular animal1 such as pestilences1 gradual extermination due to excessive trapping1 prevention of trapping1 by protective laws1 also affect the value of a fur4 ,a third factor which has an influence on the value of furs1 is the prevailing style or fashion4 ,many kinds of furs which are both beautiful and rare1 such as ,russian sable or chinchilla1 are practically unaffected by the whims of fashion4 ,but a fur of ordinary value may at times become so popular1 that the demand for it will cause its price to be greatly increased4 ,similarly1 a fur which has enjoyed a considerable vogue1 may pass out of demand for a time and consequently depreciate in value4 ,a detailed description of the various furs used in commerce is not within the scope of this work1 because such an account rightly belongs in a book on zology4 ,however1 it is desirable that the reader who is interested in the dressing and dyeing of furs should have at least a passing acquaintance with the chief furs used in commerce1 together with such of their individual characteristics as are of importance4 ,the figures given are for the average dressed skin4#a #a ,descriptions after ,w4 ,s4 ,parker1 ,deputy ,chairman1 ,fur ,section of ,london ,chamber of ,commerce1 in ,encyclopedia ,britannica1 #aath ,ed4 ,astrachan1 see ,lambs4 ,badger4--#b #a ft4 ,this is one of the few animals whose fur is darker on the belly than on the back4 ,the ,american sorts have coarse1 thick under-hair of a pale fawn or stone color1 with a growth of longer black and white hairs #c-d inches long4 ,the ,japanese varieties are usually dyed for imitation skunk4 ,the ,american kind is also dyed occasionally but is mostly used natural4 ,badger hair is very extensively used for #8pointing4' ,bear1 ,black4--#f #c ft4 ,has fine1 dark brown under-hair1 with bright1 flowing black top-hair #d inches long4 ,the fur of cubs is nearly as long1 although the skins are much smaller1 and the hair is finer1 softer1 and lighter-pelted4 ,the best skins are from ,canada4 ,bear1 ,brown4--#f #c ft4 ,similar to the ,black ,bear1 but more limited in number4 ,the color ranges from a light yellow to a rich dark brown4 ,the best and most valuable sorts come from the ,hudson ,bay territory1 inferior skins coming from ,europe and ,asia4 ,bear1 ,white4--#aj #e ft4 ,this is the largest of the bears4 ,the hair is short and close except on the flanks1 while the color ranges from white to yellow4 ,the best skins come from ,greenland1 the whitest being the most valuable4 ,beaver4--#c #b ft4 ,this is the largest of the rodents1 and is very widely used2 formerly to a great extent in the hat trade4 ,the under-hair is close and of a bluish-brown hue1 and nearly an inch deep4 ,the over-hair is coarse1 bright black or reddish-brown in color1 and is usually plucked out1 as the under-hair is the attractive part of the fur4 ,the darkest skins are the most valuable4 ,formerly beaver was used to dye in imitation of seal1 but more suitable furs are now used4 ,broadtail1 see ,lambs4 ,caracul1 see ,lambs4 ,cat1 ,civet4--#i #d-a_/b inches1 with short1 thick and dark under-hair1 and silky1 black top-hair with irregular white markings4 ,it is similar to the skunk1 but is lighter1 softer1 less full1 and has no disagreeable odor4 ,cat1 ,house4--#ah #i inches4 ,is mostly black and dark brown1 the best skins coming from ,holland4 ,the hair is weak1 coming out with the friction of wear4 ,in the trade1 the black variety is known as genet4 ,chinchilla4--#ab #g inches4 ,this is one of the rarest and most beautiful furs4 ,it comes from ,bolivia and ,peru1 where1 due to the uncontrolled trapping of the animal1 it is becoming scarce1 and this compelled the governments to enact laws prohibiting the taking of chinchilla for a certain period4 ,the fur is of a delicate blue-grey1 with black shadings1 the fur being #a-a-a_/d inches deep4 ,unfortunately1 the skin is quite perishable4 ,chinchilla1 ,la ,plata4--#i #d inches4 ,incorrectly called 8bastard chinchilla0 in the trade4 ,it is a similar species to the ,bolivian chinchilla1 but due to the lower altitude and warmer climate of its habitat1 is smaller1 with shorter and less pretty hair1 the color of the under-hair being darker1 and of the top-hair less pure4 ,it is quite as undurable as true chinchilla4 ,chinchillone4--#ac #h inches4 ,is also from ,south ,america4 ,the fur is longer1 weaker1 poorer and yellower than real chinchilla1 but the skins are often dyed in shades closely resembling the natural chinchilla4 ,ermine4--#ab #b-a_/b inches4 ,the under-hair is short and even1 with the top-hair slightly longer4 ,the leather is light1 close in texture1 and quite durable4 ,in mid-winter the color is pure white1 except the tip of the tail1 which is usually quite black4 ,the best skins are from ,siberia4 ,fisher4--#cj #ab inches1 with tail #ab-ah inches long4 ,it is the largest of the marten family4 ,the under-hair is deep1 and of a dark shade1 with a fine dark1 glossy and strong top-hair1 #b or more inches long4 ,the best skins are from ,canada4 ,the fur is something like a dark silky raccoon1 while the tail1 which is very highly prized1 is almost black4 ,fitch4--#ab #c inches4 ,it is of the marten species1 and its common name is polecat4 ,the under-hair is yellow and #a_/c of an inch deep4 ,the top-hair is black1 #a-a_/b-a-c_/d inches long1 very fine and open in growth1 and not so close as the martens4 ,the largest and best skins are from ,denmark1 ,holland and ,germany4 ,the ,russian skins are smaller1 silkier1 and are usually dyed as a substitute for sable4 ,fox1 ,blue4--#bd #h inches4 ,the under-hair is thick and long1 while the top-hair is fine and not so plentiful as in other foxes4 ,it is found in ,alaska1 ,hudson ,bay ,territory1 ,greenland and ,archangel4 ,although called blue1 the color is really of a slaty or drab shade4 ,the skins from ,archangel are more silky and of a smoky bluish color1 and being scarce are most valuable4 ,the white foxes which are dyed a smoky blue are brilliant and quite unlike the browner shades of the blue-fox4 ,fox1 ,cross4--#bj #g inches4 ,the skins generally have a pale yellow or orange tone1 with some silver points1 and a darkish cross marking on the shoulders1 on account of which the animal got its name4 ,some are very similar to the pale red foxes of ,northwest ,america4 ,the darkest and best skins are from ,labrador and ,hudson ,bay1 those from lower latitudes being inferior4 ,fox1 ,grey4--#bg #aj inches4 ,has a close dark drab under-hair1 with coarse regular1 yellowish1 grizzly-grey top-hair4 ,the majority of the skins come from ,virginia and southwestern ,u4 ,s4 ,a4 ,those from the west are larger and brighter-toned4 ,fox1 ,kit4--#bj #f inches4 ,the under-hair is short and soft1 as is also the top-hair1 which is a very pale grey mixed with some yellowish-white hairs4 ,it is the smallest of the foxes1 and is found in ,canada and northern ,united ,states4 ,fox1 ,red4--#bd #h inches1 although some kinds are larger4 ,the under-hair is long and soft1 and the top-hair is plentiful and strong4 ,the colors range from pale yellow to a dark red1 some being very brilliant4 ,it is widely found in northern ,america1 ,china1 ,japan1 and ,australia4 ,the ,kamchatka foxes are exceptionally fine and rich in quality4 ,farther north1 near the open sea1 the fur is coarse4 ,the skins have an extensive use1 both natural and dyed4 ,they are dyed black in imitation of the black fox1 or these when pointed with badger or other white hair to imitate the silver fox4 ,fox1 ,silver4--#cj #aj inches4 ,the under-hair is close and fine1 and the top-hair1 which is black to silvery1 is #c inches long4 ,the fur on the neck usually runs almost black1 and in some cases the black extends over half the length of the skin4 ,when all black1 it is a natural black fox1 and is exceedingly rare and high-priced4 ,the silver fox is very valuable1 the finest wild skins coming from ,labrador4 ,the tail is always tipped white4 ,the majority of the silver fox pelts that reach the market today are bred on ranches in ,canada and the ,united ,states4 ,fox1 ,white4--#bj #g inches4 ,it is usually small and inhabits the extreme northern sections of ,hudson ,bay1 ,labrador1 ,greenland1 and ,siberia4 ,the ,canadian are silky-haired and inclined to a creamy color1 while the ,siberian are whiter and more woolly4 ,the under-hair is generally of a bluish-grey tone1 but the top-hair in winter is usually full enough to hide such a variation4 ,those skins which have under-hair that is quite white are rare and much more expensive than the others4 ,in summer specimens of these species have slightly discolored coats1 the shades resembling those of the blue fox4 ,the skins which are not perfectly white are bleached1 or if they cannot be bleached sufficiently white they are dyed various shades of smoke color1 blue-greys and also imitation blue fox4 ,goat4--,the size varies greatly4 ,the ,european1 ,arabian and ,east ,indian varieties are used mainly for leather and wool4 ,many from ,russia are dyed black for rugs4 ,the hair is brittle1 with poor under-hair1 and is not durable4 ,the ,chinese export many skins in grey1 black and white1 made into rugs of two skins each4 ,frequently the skins are dyed black or brown in imitation of bear4 ,hamster4--#h #c-a_/b inches4 ,a destructive rodent found largely in ,russia and ,germany4 ,the fur is very flat and poor1 of a yellowish-brown color1 with a little marking of black4 ,on account of its lightness it is used for linings2 occasionally it is dyed4 ,hare4--#bd #i inches4 ,the common hare of ,europe is used mostly for the hatters' trade4 ,the white hares of ,russia1 ,siberia1 and other northern regions are the ones mainly used for furs4 ,it is whitest in mid-winter1 and the fur on the flanks is longer than that on the back4 ,the hair is brittle and not durable1 and the leather is quite as bad4 ,yet the skins are used to dye imitations of more than a dozen different furs4 ,the ,north ,american hares are also dyed black and brown4 ,kangaroo4--,the sizes vary greatly1 the larger kinds being generally used for making leather4 ,the sorts used for fur are1 blue kangaroo1 bush kangaroo1 wallaroo1 rock wallaby1 swamp wallaby1 and short-tailed wallaby4 ,many of the swamp wallabies are dyed imitation skunk1 and look quite attractive4 ,the colors are generally yellowish or brown1 some in the swamp variety being dark brown4 ,the skins are quite strong4 ,the rock wallabies are soft and woolly1 and often have a bluish tone4 ,they are used for rugs4 ,kolinsky4--#ab #b-a_/b inches4 ,it is of the marten family4 ,the under-hair is short and rather weak1 but regular1 as is also the top-hair4 ,the color is usually a uniform yellow4 ,they are generally dyed in imitation of other members of the marten family4 ,it is very light in weight1 and the best skins are obtained from ,siberia4 ,the tails are used for artists' 8sable0 brushes4 ,lambs4--,those of commercial interest are from ,south ,russia1 ,persia1 and ,afghanistan1 and include ,persian ,lamb1 ,broadtail1 ,astrachan1 ,shiraz1 ,bokhara1 ,caracul1 and ,krimmers4 ,the ,persians are #ah #i inches1 and are the finest and best4 ,when properly dressed and dyed they should have regular1 close1 bright curls1 varying from small to very large and if of equal size1 regularity1 tightness and brightness1 their value is inestimable4 ,all the above lambs1 except krimmer1 are naturally a rusty black or brown1 and are in most cases dyed a jet black4 ,luster cannot be imparted where naturally lacking4 ,broadtails1 #aj #e inches1 are the young of the ,persians1 killed before the wool has had time to develop beyond the flat wavy state4 ,they are naturally of exceedingly light weight1 and when of an even pattern possessing a lustrous sheen are costly4 ,the pelt1 however1 is too delicate to resist hard wear4 ,astrachan1 ,shiraz1 and ,bokhara lambs1 #bb #i inches1 are of a coarser and looser curl4 ,caracul lambs are the very young of the astrachan1 and the finest skins are almost as effective as the broadtails1 although not so fine in texture4 ,krimmers1 #bd #aj inches are grey lambs obtained from ,crimea4 ,they are of a similar nature to the caraculs1 but looser in curl1 and ranging in color from a very light to a dark grey1 the best being pale bluish-greys4 ,slink lambs come from ,south ,america and ,china4 ,the ,south ,american are very small1 and generally those are still-born4 ,they have a particularly thin pelt1 with very close wool of minute curls4 ,the ,chinese sorts are much larger4 ,leopard4--#c #f feet long4 ,there are several kinds1 the chief being the snow leopard or ounce1 ,chinese1 ,bengal1 ,persian1 ,east ,indian1 and ,african4 ,the first variety inhabits the ,himalayas1 and has a deep1 soft fur1 quite long as compared with the ,bengal sort4 ,the colors are pale orange and white with dark markings4 ,the ,chinese are of a medium orange-brown color and full in fur4 ,the ,east ,indian are less full and not so dark2 the ,bengal are dark and medium in color with short1 hard hair4 ,the ,african are small1 with pale lemon-colored ground1 and very closely marked with black spots4 ,lynx4--#de #bj inches4 ,the under-hair is thinner than in the fox1 but the top-hair is fine1 silky and flowing1 #d inches long1 of a pale grey1 slightly mottled with fine streaks and dark spots4 ,the fur on the flank is longer1 and white1 with very pronounced markings of dark spots1 and this part of the skin is generally worked separately4 ,skins with a bluish tone are more valuable than those with a sandy or reddish hue4 ,the lynx inhabits ,north ,america as far south as ,california4 ,the best skins come from ,hudson ,bay1 and also ,sweden4 ,they are generally dyed black or brown1 similar to dyed fox4 ,marmot4--#ah #ab inches4 ,a rodent found largely in the south of ,germany4 ,the fur is yellowish-brown1 rather harsh and brittle1 and without under-hair4 ,also found in ,north ,america1 ,china1 and the best skins come from ,russia4 ,it is dyed brown in imitation of mink or sable1 the stripes usually being put on in the completed garment4 ,marten1 ,baum4--#af #e inches4 ,also called ,pine ,marten1 and is found in the woods and mountains of ,russia1 ,norway1 ,germany and ,switzerland4 ,it has a thick under-hair with strong top-hair1 and ranges from a pale to a dark bluish-brown4 ,the best are from ,norway1 are very durable and of good appearance1 and a good substitute for the ,american sable4 ,marten1 ,japanese4--#af #e inches4 ,it is of a woolly nature with rather coarse top-hair1 and quite yellow in color4 ,it is dyed1 but it is not an attractive fur1 lacking a silky1 bright and fresh appearance4 ,marten1 ,stone4--,size and quality similar to the baum marten4 ,the color of the under-hair is stony white1 and the top-hair is a very dark brown1 almost black4 ,skins of a pale bluish tone are used natural1 while less clear colored ones are dyed1 usually in ,russian sable shades4 ,they are found in ,russia1 ,bosnia1 ,turkey1 ,greece1 ,germany1 and ,france1 the best coming from ,bosnia and ,france4 ,mink4--#af #e inches4 ,is of the amphibious class1 and is found throughout ,north ,america1 as well as in ,russia1 ,china and ,japan4 ,the under-hair is short1 close and even1 as is also the top-hair1 which is very strong4 ,the best skins are very dark1 and come from ,nova ,scotia4 ,in the central states the color is a good brown1 but in the northwest and southwest1 the fur is coarse and pale4 ,it is very durable and an economic substitute for sable4 ,the ,russian species is dark1 but poor and flat in quality1 and the ,chinese and ,japanese sorts are so pale that they are always dyed4 ,mole4--#c-a_/b #b-a_/b inches4 ,is plentiful in the ,british ,isles and ,europe1 and is much in demand on account of its velvety fur of a pretty bluish shade4 ,although the skins are comparatively cheap1 the cost of dressing is high on account of the considerable amount of labor involved4 ,the pelt is very light in weight1 but does not resist well the friction of wear4 ,monkey1 ,black4--#ah #aj inches4 ,the species usually found on the west coast of ,africa1 is the one of interest to the fur trade4 ,the hair is very long1 very black and bright1 with no under-hair1 and the white pelt is very noticeable by contrast4 ,muskrat1 ,brown1 ,black1 ,russian4--#ab #h inches4 ,a very prolific rodent of the amphibious class1 obtained in ,canada and the ,united ,states4 ,it has a fairly thick and even brownish under-hair1 and a rather strong1 dark top-hair of medium density4 ,it is a durable and not too heavy fur4 ,it is used natural1 but recently the plucked1 sheared and dyed skins have found a very extensive use as ,hudson seal1 an imitation of real seal4 ,the so-called black variety of muskrat is found in ,new ,jersey and ,delaware1 but only in comparatively small numbers4 ,the ,russian is also very small and limited in numbers4 ,it is of a pretty silvery-blue shade with even under-hair1 with very little silky top-hair1 and silvery-white sides1 presenting altogether a marked effect4 ,nutria4--#bj #ab inches4 ,is a rodent about half the size of the beaver1 and when plucked1 has only about half the depth of fur1 which is not so close4 ,it is often dyed a seal color1 but its woolly nature renders it less effective than the dyed muskrat4 ,the skins are obtained from northern ,south ,america4 ,opossum1 ,american4--#ah #aj inches4 ,is a marsupial1 the only one of its class found outside of ,australia4 ,the under-hair is of a very close frizzy nature1 and nearly white1 with long bluish-grey top-hair mixed with some black4 ,it is found in central sections of the ,united ,states1 and is frequently dyed imitation skunk4 ,opossum1 ,australian4--#af #h inches4 ,is of a totally different nature from the ,american4 ,although it has fur-hair and top-hair1 the latter is sparse and fine1 so that the fur coat may be considered one of close even under-hair4 ,the color varies according to the district of origin1 from blue-grey to yellow with reddish tones4 ,those from near ,sidney are a light clear blue1 while those from ,victoria are a dark iron-grey1 and stronger in the fur-hair4 ,the most pleasing shade of grey comes from ,adelaide4 ,the reddest are the cheapest4 ,the ring-tailed opossum1 #g #d inches1 has a very short1 close and dark grey under-fur1 some almost black1 but the skins are not used extensively4 ,the ,tasmanian opossum1 grey and black1 #bj #aj inches1 is of a similar description1 but larger1 darker1 and stronger in the under-hair4 ,otter1 ,river4--,the size varies considerably1 as does also the length of the fur1 according to the origin4 ,it is found in greatest numbers in the coldest northern regions1 and with the best under-hair1 the top-hair being unimportant1 as it is plucked out4 ,most of the best river otters come from ,canada and the ,united ,states1 and average #cf #ah inches4 ,the skins from ,germany and ,china are smaller and shorter furred4 ,the colors of the under-hair vary from very dark brown to almost yellow4 ,both the fur and the leather are extremely strong1 and many skins are dyed imitation seal after plucking4 ,otter1 ,sea4--#ej #be inches4 ,is one of the most beautiful of furs4 ,the under-hair is of a rich1 dense1 silky nature1 with short and soft top-hair1 which is not plucked4 ,the colors range from a pale grey-brown to a rich black1 and many skins have a sprinkling of white or silver-white hairs4 ,the blacker the under-hair1 and the more regular the silver points1 the more valuable is the skin4 ,pony1 ,russian4--,this is a comparatively cheap1 but very serviceable fur1 and possesses some very desirable qualities4 ,it has a thin leather1 but is also scantily haired4 ,young pelts have a design on them somewhat similar to broadtail lambs1 or moire astrachans1 but this design is lost to a considerable degree by dyeing the furs4 ,the hair1 which is very glossy1 is generally dyed black1 although the natural pelts are also worn extensively4 ,rabbit4--#aj #af inches4 ,the fur is thick and fine1 but the pelt is very weak4 ,it is a native of central ,europe1 ,asia1 ,north and ,south ,america1 ,new ,zealand and ,australia4 ,the color ranges from white to black4 ,france1 ,belgium and ,australia are the greatest producers of rabbits suitable for dyeing black1 the so-called ,french seal1 for which they are mostly used4 ,at the present time the dyeing of rabbits constitutes a considerable percentage of the total fur-dyeing operations in this country4 ,the most varied shades are produced on rabbit1 and it probably is the basis of the greatest number of dyed imitations of better furs4 ,in addition to the ,french seal1 or sealine1 rabbit is dyed in imitation of beaver1 mole1 etc4 ,raccoon4--#bj #ab inches4 ,varies considerably in size1 quality and color of the fur1 according to the part of ,north ,america in which it is found4 ,the under-hair is #a-a-a_/b inches deep1 pale brown1 with long top-hair of a dark and silvery-grey mixture of a grizzly type1 the best having a bluish tone1 and the cheapest a yellowish or reddish-brown4 ,the best skins come from the northern part of the ,united ,states4 ,the skins have a wide use natural1 but are also dyed dark blue1 or imitation skunk1 the latter being a very effective and attractive substitute1 and extensively used4 ,sometimes the skins are plucked1 and if the under-hair is good1 the effect is similar to a beaver4 ,sable1 ,american and ,canadian4--#ag #e inches4 ,the skins are sold in the trade as martens1 but since many of the skins are of a very dark color1 and almost as silky as ,russian sable1 they have come to be known as sable4 ,the prevailing color is a medium brown1 while many are quite yellow4 ,these pale skins have been dyed so well that they can cheaply substitute ,russian sable4 ,the finest skins are from the ,eskimo ,bay and ,hudson ,bay districts1 the poorest from ,alaska4 ,sable1 ,russian4--#ae #e inches4 ,belongs to a species of marten similar to the ,european and ,american1 but much more silky in the texture of the fur4 ,the under-hair is close1 fine and very soft1 the top-hair is regular1 fine and flowing1 and silky1 ranging from #a-a_/b to #b-a_/b inches in depth4 ,in color they vary from a pale stony or yellowish shade to a rich1 almost black1 dark brown1 with a bluish tone4 ,the leather is exceedingly close and fine in texture1 very light in weight1 and very durable4 ,the ,yakutsk1 ,okhotsk1 and ,kamchatka sorts are good1 the last being the largest and fullest-furred1 but of less color density than the others4 ,the most valuable1 are the darkest from ,yakutsk in ,siberia1 particularly those having silvery hairs evenly distributed over the skin1 but these furs are very rare4 ,the ,amur skins are paler1 but often of a pretty1 bluish tone1 with many interspersed silvery hairs4 ,the fur is not so close or deep1 but is very effective nevertheless4 ,the paler skins from all districts are now tipped1 the tips of the hair being stained dark1 the fastest dyes being used1 and only an expert can detect them as differing from the natural shades4 ,seal1 ,fur4--,the sizes range from #bd #ae inches to #ae #be inches1 the width being the widest part of the skin after dressing4 ,the most useful skins are the pups #db inches long1 the quality being very good and uniform4 ,the largest skins1 known as wigs1 and ranging up to #h feet in length1 are uneven and weak in the fur4 ,the supply of the best sort is chiefly from the northern ,pacific1 ,pribilof ,islands1 ,alaska1 northwest coast of ,america1 ,aleutian ,islands1 and ,japan4 ,other kinds are taken from the south ,pacific regions4 ,the dressing and dyeing of seal takes longer than for any other fur1 but when finished1 it has a fine1 rich effect1 and is very durable4 ,seal1 ,hair4--,this is chiefly used for its oil and leather1 and not for its fur4 ,it has coarse1 rigid hair1 and no under-hair4 ,skunk1 or 8,black ,marten40--#ae #h inches4 ,the under-hair is full1 and fairly close1 with glossy1 flowing top-hair about #b-a_/b inches long4 ,the majority of the skins have two stripes of white hair extending the whole length of the skin4 ,these were formerly cut out1 but more recently are dyed the same color as the rest of the skin4 ,they are widely found in ,north and ,south ,america4 ,the best are from ,ohio and ,new ,york4 ,the skunk is naturally the blackest fur1 is silky and very durable4 ,squirrel4--#aj #e inches4 ,this size refers to the ,russian and ,siberian types1 which are practically the only kind imported for fur1 other species having too poor a fur to be of great commercial interest4 ,the back of the ,russian squirrel has an even1 close fur1 varying from a clear bluish-grey to a reddish-brown1 the bellies in the former being of a flat quality and white1 in the latter1 yellowish4 ,the backs are worked up separately from the bellies4 ,the pelts1 though light in weight1 are tough and durable4 ,the tails are dark and very small1 and considerably used4 ,tiger4--,the size varies1 the largest measuring about #aj feet from the nose to the root of the tail4 ,it is found throughout ,india1 ,turkestan1 ,china1 ,mongolia1 and the ,east ,indies4 ,coats of the ,bengal variety are short and of a dark orange-brown with black stripes4 ,those from other parts of ,india are similar-colored1 but longer in hair1 while those from the north and ,china are not only large in size1 but have very long soft hair of a delicate orange-brown1 with very white flanks1 and marked generally1 with the blackest of stripes4 ,wolf4--#ej #be inches4 ,is closely allied to the dog family1 and very widely distributed over the world4 ,the best are the full-furred skins of a very pale bluish-grey with fine1 flowing black top-hair1 from the ,hudson ,bay district4 ,those from the ,united ,states and ,asia are harsher and browner4 ,the ,siberian is smaller than the ,north ,american1 and the ,russian still smaller4 ,a large number of prairie-dogs1 or dog-wolves1 is also used for cheaper furs4 ,wolverine4--#af #ah inches4 ,is a native of ,america1 ,siberia1 ,russia1 and ,scandinavia1 and is of the general nature of the bear4 ,the under-hair is full and thick1 with strong1 bright top-hair about #b-a_/b inches long4 ,the color is of two or three different shades of brown on one skin1 the center being dark1 and presenting the general appearance of an oval saddle1 bordered with a rather pale shade of brown1 and merging to a darker shade towards the flanks4 ,this peculiar character stamps it as a distinguished fur4 ,it is expensive1 and quite valuable on account of its excellent qualities4 ,wombat1 ,koala or ,australian ,bear4--#bj #ab inches4 ,it has a light grey or brown1 close1 thick under-hair #a_/b inch deep1 and no top-hair1 with a rather thick1 spongy pelt4 ,it is cheap1 and well suited for rough wear4 ,,chapter ,,ii ,,structure ,,of ,,fur ,fur is made up of two main components1 the hair and the skin1 and each of these has a very complex structure4 ,in the living animal the skin serves as a protective covering1 and also constitutes an organ of secretion and of feeling2 consequently it is of a highly complicated nature4 ,the skin of all fur-bearing animals is essentially the same in structure1 although varying considerably as to thickness and texture4 ,it consists of two principal layers1 which are entirely different in structure and purpose1 and correspondingly different in both physical and chemical respects3 the epidermis1 epithelium or cuticle1 which is the outer layer1 and the dermis or corium1 which is the true skin4 7,fig4 #a;,a74 ,the epidermis is very thin as compared with the corium4 ,its outer layer consists of a tissue of cells1 somewhat analogous to the horny matter of nails and hair4 ,the inner surface1 called the #8rete malpighi1' rests on the true skin1 and is a soft1 mucous layer of cells4 ,these cells are spherical when first formed1 but as they approach the surface become flattened1 and dry up1 forming the horny outer layer of the epidermis1 which is constantly throwing off the dead scales1 and which is constantly being renewed from below4 ,it is from this inner layer of the epidermis that the hair1 the sweat-glands1 and the fat-glands are developed4 ,the corium1 or true skin1 consists essentially of white1 interlacing fibres of the kind known as connective tissue4 ,these fibres are themselves made up of extremely fine smaller fibres1 or fibrils1 cemented together by a substance of a somewhat different nature from the fibres1 the coriin4 ,towards the center of the skin1 the texture of the interweaving fibres is looser1 becoming much more compact at the surface just beneath the inner layer of the epidermis4 ,this part of the corium is so exceedingly close that the fibrils are scarcely recognizable4 ,it is in this part that the fat-glands are situated1 while the hair-roots and sweat-glands pass through it into the looser texture of the corium4 ,the surface next to the flesh is also closer in structure than the middle portions of the skin1 and has somewhat of a membranous character due to the fibres running almost parallel to the surface of the skin4 ,the skin is joined to the body proper by a network of connective tissue1 frequently full of fat-cells4 ,this layer1 together with portions of the flesh which may adhere to it1 is removed by the process called #8fleshing1' and this side of the skin is known as the flesh side4 ,the corium also contains a small proportion of yellow fibres1 known as #8elastic fibres1' which differ physically and chemically from the rest of the skin substance4 ,during the course of the development of the embryo animal1 a small group of cells forms like a bulb on the inner side of the epidermis1 above a knot of very fine blood-vessels in the corium4 ,this group of cells grows downward into the true skin1 and the hair-root which is formed within it1 surrounds the capillary blood-vessels1 drawing nourishment from them1 and thus forming the papilla4 7,fig4 #a;,a74 ,smaller projections also form on the bulb1 and the fat-glands are gradually developed4 ,the sweat-glands are formed in a manner similar to the development of hair4 ,the individual hair fibre is quite as complicated in structure as the skin1 and is made up of four distinct parts4 7,fig4 #a;,b74#b #b ,descriptions and figures taken from 8,mammal ,fur ,under the ,microscope10 by ,dr4 ,l4 ,a4 ,hausman1 in ,natural ,history1 ,sept4-,oct41 #aibj4 ,the medulla1 or pith1 is the innermost portion of the hair1 and is composed of many shrunken cells1 often connected by a network which may fill the medullary column partially or wholly4 ,surrounding the medulla is the cortex1 which is made up of spindle-shaped cells fused into a horny1 almost homogeneous1 transparent mass1 and forming a large proportion of the hair shaft4 ,in the majority of the fur-bearing animals1 there is distributed within and among the cells of the cortex a pigment in the form of granules or minute particles1 arranged in the different hairs in fairly definite and characteristic patterns4 ,it is to these pigment granules that the color of the hair is due primarily4 ,in some cases the coloring matter of the shaft is uniformly diffused and not granular4 ,illustration3 ,,fig4 #a ,a4 ,,structure ,,of ,,skin4 ,b4 ,,structure ,,of ,,hair4 ,the outermost coat of the hair1 or cuticle1 is composed of thin1 colorless1 transparent scales of varying forms and sizes1 and arranged in series like the shingles of a roof4 ,it is on these scales that the lustre or gloss of the hair depends4 ,since lustre is due to the unbroken reflection of light from the surface of the hair1 the smoother the surface1 the glossier it will appear4 ,when the scales of the cuticle are irregular and uneven1 the surface of the hair will not be uniform and smooth1 and the light reflected from it will be broken and scattered1 and consequently the hair will not possess a high degree of lustre4 ,as a rule1 the stiff1 straight hairs have the most regular and uniform arrangement of the scales of the cuticle1 and hence are the smoothest and glossiest4 ,fur hairs are in general either circular or elliptical in cross-section1 those which are circular being straight or only slightly curved1 while those which are elliptical in cross-section are curly like the hair of the various kinds of lambs4 ,most fur-bearing animals have two different kinds of hair on their bodies4 ,nearest to the skin is a coat of short1 thick1 soft and fine hair1 usually of a woolly nature1 and called the under-hair1 under-wool1 or fur-hair4 ,overlying the fur-hair is a protective layer of hair1 longer and coarser than the under-hair1 and usually straight1 hard1 smooth and glossy4 ,this is called the top-hair1 over-hair1 guard-hair or protective hair4 ,in some furs1 the top-hair constitutes one of the chief elements of their beauty1 while in others1 the top-hairs are removed1 so as better to display the attractive features of the under-hair4 ,the roots of the top-hair are generally deeper in the skin than those of the fur-hair1 and in some instances where the top-hair is removed1 as in the seal1 the roots are destroyed by the action of chemicals applied to the skin side1 the roots of the fur-hair being wholly unaffected by this treatment4 ,the fur-hair and the top-hair in the same animal have different medullary and cuticular structures1 and these characteristics may be used to distinguish the two kinds of hair4 ,figs4 #b;,a and ,b illustrate these differences4 ,in each case1 the two large hairs on the left of the illustration are the guard-hairs1 showing respectively the cuticular scales and the medulla4 ,on the right are the two fur-hairs showing the scales and the medulla4 ,although composed of many different kinds of tissues1 and varying so greatly in physical structure1 both the skin and the hair belong to the same class of chemical compounds1 namely the proteins4 ,these are highly complex substances1 forming the basis of all animal and vegetable tissues4 ,there are many different kinds of proteins1 varying somewhat in their constitutions1 but all show1 on analysis the following approximate composition of chemical elements3 ,carbon #ej-ee ,hydrogen #f4e-g4c ,nitrogen #ae-ag4f ,oxygen #ai-bd ,sulphur #j4c-e ,the principal kinds of proteins found in the various fur structures are albumins1 keratin1 collagen1 and mucines4 ,albumins1 of which the white of egg is the most familiar variety1 occurs to some extent in the corium as serum in the blood-vessels1 and also as the liquid filling the connective tissues1 known as the lymph4 ,they are soluble in cold water1 but when heated to about #gj ,c41 they coagulate and are then insoluble4 ,concentrated mineral acids and strong alcohol will also effect coagulation4 ,illustration3 ,,fig4 #b ,a4 ,,hair ,,of ,,european ,,beaver4 a4 ,,top-,,hair4 b4 ,,under-,,hair4 ,b4 ,,hair ,,of ,,skunk4 a4 ,,top-,,hair4 b4 ,,under-,,hair4 ,keratin is the chief substance of which all horny parts of the animal body are composed1 such as the hair1 nails or hoofs4 ,it is the principal constituent of the hair1 the epidermis1 and the walls of the cells of the inner layer of the epidermis1 or the #8rete malpighi4' ,keratin is particularly rich in sulphur1 and is quite insoluble in cold water4 ,caustic alkalies attack keratin-containing parts4 ,the collagens are the principal proteins of the skin1 forming largely the substance of the connective tissue fibres1 and consequently the framework of the skin4 ,they are insoluble in cold water1 dilute acids and salt solutions1 and are only very slowly attacked by dilute alkalies4 ,dilute acids and alkalies cause collagen to swell2 concentrated acids1 vegetable tanning materials1 basic chrome or iron salts cause it to shrink4 ,by boiling with water1 dilute acids or dilute alkalies1 collagen is split up into gelatin or glutin4 ,the mucines of the skin1 intercellular material or coriin1 are soluble in dilute acids1 in dilute solutions of alkalies and of alkaline earths such as lime1 and in #aj salt solution1 but insoluble in water1 and in salt solutions of greater or less concentration than #aj4 ,on drying the skin1 the mucines cement the connective tissue fibres1 causing the skin to become stiff1 horny and translucent4 ,the mucines are also constituents of the cells of the #8rete malpighi4' ,the solubility of the mucines in dilute solutions of alkalies and of alkaline earths causes the epidermis to be loosened from the corium1 when the skins are treated with such solutions for some time4 ,when raw skins are boiled with water1 the greater part goes into solution1 the residue consisting chiefly of the keratins of the hair and epidermis cells4 ,on cooling1 the solution solidifies to a jelly of gelatine4 ,it combines with both acids and alkalies4 ,a property of the skin which is of importance in the tanning operation of fur-dressing1 and a quality which also characterizes gelatine1 is the capacity to absorb liquids and swell up1 without changing chemically4 ,raw pelts swell up easily in pure cold water1 but much more easily in solutions of dilute acids or dilute alkalies1 only a little of the skin material being dissolved4 ,in stronger solutions1 the skins swell up less1 while more of the skin substance dissolves1 and by prolonged action of strong acids or alkalies1 an almost complete solution of the skin is obtained1 without1 however1 any of the material decomposing4 ,with very strong alkalies or acids1 the skin substance is broken up into simpler compounds1 such as various amines and ammonia4 ,the swelling action of acids or of alkalies increases with the increase in concentration of the acid or alkali1 but only up to a certain point1 after which further increase in the strength of the acid or alkaline solution causes a reduction in the swelling1 and even produces shrinkage4 ,in the presence of neutral salts1 like common table salt1 sodium chloride1 the swelling action of acids1 is reduced1 but the action of alkalies remains practically unaffected4 ,when treated with the various chemicals1 fur hair acts in a manner quite similar to wool4 ,if it be remembered that certain classes of furs are derived from animals of the sheep family1 such furs as ,persian lamb1 krimmer1 etc41 it becomes apparent why chemicals should affect furs in nearly the same way as wool4 ,the great majority of furs differ from those of the sheep family1 in possessing much greater resistance to the action of chemicals4 ,the range is a wide one however1 and no exact criterion can be adopted4 ,as a general rule1 the reactions are most marked with fur-hair of a woolly nature1 so this may be taken as a standard of reference4 ,acids have relatively little action on the hair1 when applied in dilute solutions4 ,the scales of the cuticle or epithelium are somewhat opened1 the fibre becoming slightly roughened thereby4 ,even at high temperatures1 the hair is quite resistant to the action of dilute acids4 ,concentrated acids destroy the hair with the liberation or formation of ammonia1 hydrogen sulphide1 and various amino acids4 ,when treated with dilute acids1 the hair1 especially if it is of a very woolly nature1 retains considerable quantities of acid1 this phenomenon being probably due to the fixation of the acid by the basic groups in the hair4 ,nitric acid produces a yellow coloration when applied in dilute solution for a short time4 ,sulphurous acid1 the acid formed by the burning of sulphur1 has a bleaching action on the hair4 ,alkalies attack the hair1 even in dilute solutions1 and by longer action complete decomposition sets in1 with formation of ammonia and amino-acids4 ,ammonium carbonate1 soap1 and borax are practically harmless in their effect on the hair4 ,sodium and potassium carbonates roughen the hair on prolonged action1 even in dilute solutions4 ,calcium hydroxide on continued action removes sulphur from the hair1 causing it to become brittle4 ,salts of alkalies and alkaline earths do not affect the hair at all4 ,salts of the heavy metals on the other hand1 are absorbed in appreciable quantities4 ,from a dilute solution of alum1 aluminum hydroxide is absorbed by the hair1 the potassium sulphate remaining in solution4 ,similarly with copper1 iron1 and chromium salts1 the metal oxides are fixed by the fibre4 ,,chapter ,,iii ,,fur ,,dressing ,,introductory ,,and ,,historical ,fur dressing has a twofold purpose4 ,first of all1 the putrefactive processes must be permanently stopped1 so that the skin may be preserved as such1 or worked up as some fur garment1 without danger of decomposition4 ,having taken measures to assure the endurance or relative permanency of the pelt1 the prime consideration is1 of course1 the appearance of the hair4 ,the hair must be so treated that all its inherent beauty is brought out to the fullest extent4 ,it must be made clean and soft1 and all the natural gloss must be preserved1 and if possible1 enhanced4 ,the appearance of the leather is relatively unimportant1 since it is not seen after the furs are made into garments4 ,there are1 however1 certain qualities which it is essential for the leather to possess after being dressed1 and these are1 softness1 lightness of weight1 elasticity or stretch1 and a certain firmness or #8feel4' ,in other words the important considerations in fur dressing are the employment of means1 and the exercise of care to preserve or even improve those characteristics of the pelt which make it valuable4 ,the dressing of furs has many features in common with the manufacture of leather1 which is a kindred art4 ,but whereas in fur dressing the prime consideration is the appearance of the hair1 and the leather is of secondary importance1 in the production of leather1 the hair plays no part at all1 since it is entirely removed from the pelt4 ,the fundamental points of resemblance between leather manufacture and fur dressing are in those processes and operations which are concerned with the preservation of the leather1 and rendering it in the proper condition for use4 ,both leather dressing and fur dressing have an origin which may be regarded as identical1 and which dates back to the haziest periods of antiquity4 ,in the course of satisfying his needs1 primitive man killed the animals about him1 and thus obtained his food4 ,the killed animal also furnished a skin1 which after undergoing certain manipulations and other treatments1 could serve as a protective covering1 ornament1 or defensive weapon4 ,since the skin in its natural state was hardly fit for use because of its easy tendency to putrefaction1 it is evident that man had to find some means of preventing this decay in a more or less permanent fashion1 and moreover had to treat the skin so that it would be suitable for use1 by rendering it soft and flexible4 ,the discovery of means to accomplish these purposes was probably one of the first great steps forward on the path of progress and civilization4 ,there are evidences of the use of animal skins in the earliest periods of antiquity1 in fact it is a usage which may be literally regarded as 8old as the hills40 ,one of the earliest written records of the employment of the skins of animals as garments1 is in the ,old ,testament1 where it states1 8,unto ,adam and to his wife did the ,lord ,god make coats of skins1 and clothed them40 ,numerous other biblical references indicate the use of animal skins for various purposes1 sometimes prepared as leather1 with the hair removed4 ,among the ,egyptians tanning seems to have been a common occupation4 ,the particularly attractive skins1 like those of the leopard or panther1 were especially prized1 and were made up as furs for ornamental wear1 rugs and decorations4 ,the less valuable skins were unhaired and made into leather4 ,although the tanning or leather-producing processes of the ,egyptians are quite unknown1 numerous figures engraved in stone afford an indication to some of the manipulatory operations1 such as soaking the skins1 fleshing1 softening with stones1 stretching over a three-legged wooden 8horse10 etc4 ,many articles1 made of leather1 have been found in the various ,egyptian sarcophagi1 and all are in a splendid state of preservation1 after forty centuries1 thereby indicating a very efficient method of dressing animal skins4 ,likewise1 the presence in the museums of various articles1 leather and fur1 of ,assyrian1 ,phoenician and ,persian origin1 tends to show that these peoples also possessed a considerable degree of proficiency in tanning4 ,frequent references in the ,greek literature show that leopard and lion skins were worn as war cloaks1 and they undoubtedly were properly made4 ,in the ,iliad is described an operation for the preparation of skins for use as garments1 and the method seems to be a sort of chamois dressing4 ,the first method of tanning skins was1 in all probability1 that of rubbing into the skins various fatty materials found close at hand1 such as parts of the animal1 fat1 brains1 milk1 excrement1 etc41 such an operation constituting the basis of what is now known as the chamois dressing4 ,one of the reasons for believing that it was the first process to be used by primitive man1 is the fact that certain undeveloped tribes and races of the present day still dress skins by it4 ,the ,american ,indians1 even to this day prepare skins by rubbing in1 on the flesh side1 the brains of the animals which furnished the skins4 ,the ,eskimos dress skins by rubbing in animal fats or fish-oil1 and subsequently softening and stretching the skins with their teeth in place of1 or for want of other implements4 ,usually1 however1 variously shaped stones or bones of animals are used to obtain the proper degree of softness and flexibility4 ,it is true1 too1 that some of the skins dressed in this primitive fashion can scarcely be excelled by any dressed with more modern processes and tanning methods4 ,the next step forward in the preparation of animal skins for use was undoubtedly the utilization of substances found in the earth4 ,common salt1 sodium chloride1 was the most universally used substance of mineral origin1 just as it is today4 ,our prehistoric ancestors eventually discovered the preservative action of salt1 and applied it to skins4 ,while it was effective1 it was not sufficiently permanent1 so another mineral1 also of very common and wide occurrence was used in combination with the salt1 and the result proved quite satisfactory4 ,this second common mineral was alum4 ,the use of alum1 which is the basis of numerous tanning processes to this day1 seems to have been quite a popular method of ancient times4 ,artemidorus1 a ,greco-,roman writer1 mentions the use of alum by the ,greeks1 and the ,romans are known to have prepared a soft1 flexible leather called aluta 7alum leather71 by using it4 ,in view of the fact that ,egypt had extensive deposits of alum1 it is believed that the alum-salt process was employed also by the ,egyptians in the preparation of leather4 ,however1 the evidence on this point is not conclusive4 ,one of the most important methods of producing leather1 either as such or on furs1 was with the aid of certain vegetable extracts1 known as the tannins1 from which the process of tanning gets its name4 ,the discovery of the value of these materials for converting the decaying raw skin into a leather which could be preserved for an almost indefinite length of time1 and which was flexible and soft as desired1 was of far-reaching importance4 ,for it is only in very recent times that these tannins have been superseded in part by new tanning substances whose use is simpler and more time-saving4 ,yet there are unmistakable indications that the tannins were employed for tanning at a period which reaches back to the dawn of history4 ,although it is scarcely probable that the people who used these materials could have known of the existence or the nature of the particular substances in the vegetable extracts which actually effect the tanning action1 experience taught them to employ these plants which possessed the highest content of active ingredients1 and which1 consequently1 were most effective in use4 ,tychios1 of ,boetius1 a ,greek supposed to have lived about #ijj ,b4,c4 and mentioned in the ,iliad1 is considered the oldest known tanner1 and was regarded by ,pliny1 a ,roman writer1 as the discoverer of tanning1 and of the use of the various vegetable tanning materials4 ,at any rate1 the ,greeks used the leaves of a so-called tanning-tree1 which was probably the sumach4 ,the ,egyptians worked with the acacia1 while the ,romans used as tanning materials the barks of the pine1 alder and pomegranate trees1 also nut-galls1 sumach and acorns4 ,the ,romans were quick to employ methods used by the peoples whom they conquered1 and it is in this way that they learned the use of many of the plants mentioned1 for tanning purposes4 ,many other ancient peoples had various processes of tanning1 the methods probably differing in each country4 ,thus the ,chinese1 ,syrians1 and much later1 the ,moors1 were each known for proficiency in a certain class of leather tanning4 ,it has been said that in general1 even up to modern times1 tanning with nut-galls was the characteristic method of the ,orient2 with oak-tan1 that of the ,occident1 while the use of alum is regarded as the method peculiar to the ,saracens4 ,in prehistoric times and the early centuries of civilization1 skins or pelts were prepared for use by the individual1 the work usually being done by the housewife and daughters1 while the masculine members of the family were engaged in hunting the animals and obtaining the skins4 ,at a later period1 when people had advanced to the point where they lived in cities1 the preparing or dressing of skins became centered in the hands of a comparatively small number of people1 and thus the work took on the aspects of a trade4 ,the workers in fur were at first the same people who made leather out of the skin1 for the two kinds of work were very closely associated4 ,during the period of the ,roman supremacy1 historical records show that the furriers1 who did all the work connected with furs1 from purchasing the raw skins1 dressing them1 making them into garments1 to selling the latter1 were organized into associations together with the leather workers4 ,after the fall of the ,roman empire1 and throughout the centuries known as the ,dark ,ages1 all traces of the furriers seem to have been lost1 but in the beginning of the ,renaissance period in the fourteenth and fifteenth centuries1 we again find records of the furriers1 who were now all members of the furriers' guilds1 also in association with the leather workers4 ,as formerly1 all the work connected with the production of fur apparel from the raw furs1 was done by the master furrier and his apprentices4 ,the methods and the implements used1 were essentially the same as in ,roman times1 and in fact1 up to a very recent period there was very little change in either4 ,with the advent of the great industrial era at the beginning of the nineteenth century1 the guild system became ineffective1 but the furriers continued their work as heretofore4 ,up to about the middle of the nineteenth century1 the furrier continued to be the only factor of any importance in the fur trade4 ,there was no need for speed in his work1 for the demands of the trade were not so urgent4 ,the fact that the dressing of furs often occupied two to four weeks was no deterring factor in his business4 ,however1 with the great expansion of the fur trade about this time1 it became impossible for the individual furrier to do everything himself1 and keep up with the requirements of his customers4 ,specialization commenced1 and establishments were set up solely for fur dressing4 ,the traditional time- and labor-consuming processes were still used1 but the efficiency of work on a large scale enabled the fur dressers successfully to fill their orders4 ,but the fur trade continued to grow by leaps and bounds1 and very soon the fur dressers were no longer able to meet the demands of the trade4 ,it was then that the science of chemistry came to the aid of the fur dresser1 and helped him meet the exigency4 ,by devising dressing processes which were cheap and efficient1 and which only required several hours1 or at the most one or two days1 as compared with as many weeks1 the chemist brought the fur dresser out of his dilemma4 ,and with the adoption of mechanical time- and labor-saving devices1 the fur dressing industry has made wonderful progress4 ,,chapter ,,iv ,,fur ,,dressing ,,preliminary ,,operations ,the fur dresser receives the skins in one of two shapes1 flat or cased1 depending on the manner in which they were removed from the animal4 ,flat skins1 as for example1 beaver1 are obtained by cutting on the under side of the animal from the root of the tail to the chin1 and along the inner side of the legs from the foot to the first cut4 ,the skins are either fastened to boards or attached to wooden hoops slightly larger than the skins1 so as to stretch them1 and are then carefully dried1 avoiding direct sunshine or artificial heat1 as it is very easy to overheat the skins and thereby ruin them4 ,the great majority of skins1 however1 are cased4 ,the pelts are cut on the under side of the tail1 and along the hind legs across the body1 the skin being then removed by pulling it over the head off the body like a glove1 trimming carefully about the ears and nose4 ,the skin is thus obtained inside out1 and is drawn over a stretching board or wire stretcher of suitable shape and dimensions1 so as to allow the skin to dry without wrinkling4 ,the pelts1 after drying in a dry1 airy place1 are removed from the stretchers and are ready for the market4 ,with some furs1 as foxes1 the skins are turned hair-side out while still somewhat moist1 and then put on the stretcher again till fully dried4 ,in most cases1 however1 skins are sold flesh-side out4 ,throughout the various dressing operations cased skins are kept intact1 being turned flesh-side out or hair-side out according as the processes are directed to the respective sides4 ,the pelts are only cut open if they have to be dyed1 or after the manufacturer receives them1 when they have to be worked into manufactured garments4 ,a distinction which is made by fur dressers and dyers1 and also by the fur trade in general1 divides furs into those derived from domestic animals1 particularly the various kinds of sheep1 including also the goat species1 and those obtained from other animals by trapping4 ,in fact1 at one time1 and to a certain extent even to-day1 dressers were divided into two groups based on this distinction1 one class dealing only with furs obtained from the sheep family1 and the other working with other kinds of furs4 ,this differentiation is not a simple arbitrary one1 but has a rational justification4 ,as mentioned before1 the manner and habit of living of the animal are important factors in determining the nature and constitution of its skin1 both leather and hair4 ,the structure of the body being dependent primarily upon the nature of the food absorbed by the animal1 it is only natural that herbivorous or vegetable-eating animals such as sheep and goats1 should possess fur of a different sort from that of the carnivorous or meat-eating animals1 such as the majority of fur-bearers are4 ,it also seems clear that furs differing in their character and constitution should require somewhat different treatments1 and accordingly the methods are modified when furs like lambs or goats are dressed4 ,to a great extent1 however1 the fundamental operations are similar for all furs1 regardless of nature or origin1 and these will be discussed briefly4 ,inasmuch as the first great purpose of fur dressing is to render the skins more or less permanently immune from the processes of decay1 it is necessary to prepare the pelts so as to be most fit to receive the preserving treatment4 ,the skins as they are delivered to the fur dresser have1 in the majority of cases1 been stretched and dried to preserve them temporarily1 while in some instances1 especially with the larger furs like bears and seals1 they are salted and kept moist4 ,the flesh-side of the pelt still has considerable fleshy and fatty tissues adhering to it1 and the hair is generally soiled and occasionally blood-stained4 ,in order to get the pelts into such a condition that they can be worked and manipulated1 they first have to be made soft and flexible4 ,very greasy skins are scraped raw in order to remove as much as possible of the attached fat1 the operation being known as beaming or scraping4 ,the typical beam1 shown in ,fig4 #c1 consists of a sloping table usually made of some hard wood1 and placed at an angle of about #de4 ,it is generally flat1 although in some instances convex beams are also used1 about a yard long1 #h to #aj inches wide1 and firmly supported at the upper end4 ,the skin is placed on the beam1 flesh-side up1 and is scraped with a two-handled knife 7,fig4 #d71 always in a downward direction4 ,illustration3 ,,fig4 #c4 ,,beam4 ,illustration3 ,,fig4 #d4 ,,knives ,,used ,,in ,,fur ,,dressing4 ,the first step in softening the skins is to get them thoroughly moistened1 and this is variously done1 depending on the nature of the skin4 ,lambs1 for example1 require the gentlest means of wetting them1 while rabbits can stand soaking in water for several days4 ,the manner and duration of moistening must be adjusted to the character of the pelt4 ,for the putrefactive processes which were stopped by stretching and drying the skins1 continue as soon as the pelt is again moistened4 ,the progress of decay causes the evolution of certain gases1 the simplest of which is ammonia1 and eventually1 if permitted to proceed1 brings about the complete disintegration of the skin tissue4 ,it has been found that a certain amount of gas formation is necessary to loosen up the fibres in order to get the best quality of leather after tanning4 ,this process must be interrupted at the proper time and not allowed to proceed too far4 ,skins which have been preserved fresh by salting1 require only a comparatively short time 7about #b hours7 to become softened by soaking in clean1 soft water4 ,most dried skins need a longer treatment before they are sufficiently flexible4 ,the addition of certain substances to the water facilitates and accelerates the softening4 ,in some instances salt water is used for soaking the pelts1 the preservative action of the salt tending to prevent any loosening of the hair4 ,a solution of #a_/d borax is very effective in rendering the skins soft1 and clean as well4 ,borax has an exceedingly mild alkaline action1 and causes a slight swelling of the skin tissue1 which then absorbs the water more readily4 ,being also preservative and antiseptic1 borax tends to prevent decomposition of the skin tissue4 ,another chemical of a different nature1 but equally effective is formic acid1 used in the proportion of #a4e-b4e parts per #ajjj parts of water4 ,formic acid also induces a swelling of the skin1 the pelts being soaked in a short time1 and the antiseptic action of the acid obviates the possibility of the hair becoming loose4 ,the water used should be fresh and clean1 and the soaking must be stopped as soon as the skins have become soft and flexible4 ,sometimes the skins are allowed to soak overnight in water1 while in other cases1 the pelts are just moistened by dipping in water until thoroughly wet1 and then laying them in a pile for several hours1 or overnight4 ,another method which is practised with certain types of skins is the use of wet sawdust or of sawdust moistened with salt water4 ,the fur skins are either embedded in the sawdust or drummed with it for several hours1 or until sufficient moisture has been absorbed to render them flexible4 ,by this means there is no danger of the skins being over-soaked1 or of the hair being loosened4 ,when the skins have been properly wetted1 they are drawn with the flesh-side across the edge of a dull knife-blade1 in order to help loosen the texture of the skin4 ,they are then put into a tramping machine and worked until completely softened4 ,in the case of large or heavy skins1 the moistened pelts are worked on the beam with a dull beaming knife to impart thorough softness and flexibility4 ,the pelts are then cleaned with particular reference to the hair4 ,with some furs this is accomplished simply by drumming for several hours with dry sawdust1 whereby the oil and dirt are removed from the hair1 and the hair is then freed from the sawdust by caging4 ,other skins are washed1 being passed through a weak soap solution for a short time1 the dirty spots being brushed4 ,occasionally an extract of soap-bark is used in place of the soap1 being even more effective4 ,the cleansed skins are then thoroughly rinsed to remove any of the cleaning material1 which would affect the gloss of the hair if allowed to remain on the skins4 ,then in order to eliminate as much as possible of the water in the skins1 they are hydro-extracted1 a centrifugal machine of the type shown in ,fig4 #e being used4 ,the basis of its action depends on the utilization of the principle of centrifugal force4 ,the machine consists essentially of a perforated metal basket generally made of copper1 capable of being rotated at a high speed4 ,surrounding the basket is an iron framework1 polished or enamelled on the inside4 ,the wet skins are placed in the rotating basket1 fur side toward the perforations1 and the water which is thrown off from the skins passes through the little holes1 and is caught up on the walls of the outside frame1 from where it is led off through suitable ducts4 ,the centrifugal device is properly equipped with balancing and regulating attachments1 as well as with a brake4 ,the power may be applied by the over-drive or the under-drive as is most desirable in the particular case4 ,the inner surface of the basket can also be enamelled or otherwise made resistant to the action of acids or other chemicals4 ,illustration3 ,,fig4 #e4 ,,centrifugal ,,machine4 7,fletcher ,works1 ,inc41 ,philadelphia7 ,when the skin is removed from the animal1 as much as possible of the adhering fat and flesh is scraped off1 but in spite of this1 and in spite of subsequent beaming by the fur dresser1 there is always a thin layer of flesh and fatty material remaining and this must be removed so as to expose the corium1 enabling the efficient action of the chemicals used in the tanning processes4 ,the process of removing this undesirable layer from the flesh-side is known as fleshing4 ,it is a rather delicate operation1 requiring considerable experience and dexterity on the part of the worker1 for it is exceedingly easy to cut into the skin and damage the fur4 ,a fleshing knife of the type commonly used is shown in ,fig4 #f4 ,it consists of a sharp blade fastened at a slight angle from the vertical1 with the cutting edge away from the workman1 who straddles the bench1 and by drawing the skins back and forth across the edge of the blade1 removes all flesh and fat1 leaving the corium free and clean4 ,large skins cannot conveniently be fleshed in this fashion4 ,they are placed on the beam1 and fleshed with a fleshing or skiving knife similar to the beaming knife1 but consisting of a slightly curved1 sharp two-edged blade having handles at both ends4 ,frequent attempts have been made to use suitable machines to do this work4 ,a type of machine which has met with considerable success is depicted in ,fig4 #g4 ,it is fashioned after the models used for the fleshing of hides for leather manufacture1 and has special adjustments and regulating devices which afford protection for the hair part of the fur4 ,from time to time other fleshing machines are put on the market1 yet none of them seems to enjoy any great popularity1 for fleshing is still largely a manual operation4 ,with some classes of pelts1 fleshing presents some difficulties1 and chemical means have to be resorted to in order to loosen the flesh sufficiently to enable proper fleshing4 ,in the case of large furs like bears1 leopards1 and the like1 which while of no great importance in the fur trade1 are occasionally met by the fur dresser1 the skins after being soaked1 and washed with soap-water1 are partially dried2 then the flesh-side is treated with technical butter or oil1 which is tramped in4 ,a mixture of salt water and bran is then applied to the skins1 thereby causing a swelling action to set in1 and the flesh becomes loosened1 and is easily removed by fleshing on the beam4 ,seals receive a special treatment which makes them soft1 and gives them greater stretch after they are tanned4 ,a paste made by mixing a very dilute solution of caustic soda with an inert substance like ,french chalk1 china clay1 etc41 is applied to the corium after the skins have been fleshed1 then the pelts are folded up1 and allowed to lie for several hours4 ,they are then entered into a dilute solution of calcium chloride and left overnight4 ,after being washed in a paddle or drum1 first with fresh water1 and then in water containing lactic or formic acid to remove the lime1 the skins are ready for tanning4 ,illustration3 ,,fig4 #f4 ,,fleshing ,,knife ,,on ,,bench4 ,illustration3 ,,fig4 #g4 ,,fleshing ,,machine4 7,turner ,tanning ,machinery ,co41 ,peabody1 ,mass47 ,,chapter ,v ,,fur ,,dressing ,,tanning ,,methods ,after the pelts have gone through the preliminary operations of softening1 washing and fleshing1 they are ready to receive the treatment which will convert the easily decomposing skin into leather of more or less permanency1 depending on the method used4 ,during the past century1 considerable study has been made both by scientific and technical people1 of the problem of leather formation4 ,numerous theories as to the nature of the process have been evolved1 but even to this day1 no satisfactory explanation has been given which would account for all the facts as they are now known1 so the matter is still a subject of considerable controversy4 ,procter1 who is one of the leading authorities on leather today discusses the development of the tanning theories as follows3 8,the cause of the horny nature of dried skin is that the gelatinous and swollen fibres of which it is composed not merely stiffen on drying but adhere to a homogeneous mass1 as is evidenced by its translucence4 ,if in some way we can prevent the adhesion of the fibres while drying we shall have made a step in the desired direction1 and this will be the more effective the more perfectly we have split the fibre-bundles into their constituent fine fibrils1 and removed the substance which cements them4 ,the separation of the fibres can be partially attained by purely mechanical means4444 ,knapp1 to whom we owe our first intelligible theories of the tanning process1 showed that by physical means the separation and drying of the fibres could be so far effected as to produce without any tanning agent a substance with all the outward characteristics of leather1 although on soaking it returned completely to the raw hide state4 ,he soaked the prepared pelt in absolute alcohol1 which penetrated between1 and separated the fibres and at the same time dried them by its strong affinity for water4 ,more recently1 ,meunier has obtained a similar result by the use of a concentrated solution of potassium carbonate which is even more strongly dehydrating4 8,knapp made a further step by adding to his alcohol a small quantity of stearic acid which1 as the alcohol evaporated1 left a thin fatty covering on the fibres which completely prevented their adhesion1 and reduced their tendency to absorb water2 and he so produced a very soft and white leather4 ,somewhat similar are the principles of the many primitive methods which apply fatty and albuminous matters1 grease1 butter1 milk1 or brains to the wet skin1 and by mechanical kneading and stretching1 aided by capillarity1 work these matters in between the fibres as the water evaporates4 ,such methods are still used1 and enter into many processes in which other tanning agents are also employed4 8,building upon these facts1 ,prof4 ,knapp advanced the theory that the effect of all tanning processes was not to cause a change in the fibres themselves1 chemical or otherwise1 but merely to isolate and coat them with water-resisting materials which prevented their subsequent swelling and adhesion4 ,true as this theory undoubtedly is in many cases1 it can hardly be accepted as the whole truth1 and it seems incontestable that frequently the fibres themselves undergo actual chemical changes which render them insoluble and nonadhesive4 8,before ,knapp's work1 the prevalent theory1 at least as regards vegetable tannage1 had been a chemical one1 started by ,sir ,humphrey ,davy4 ,if a solution of gelatine be mixed in proper proportion with one of tannin1 both unite to form a voluminous curdy precipitate2 and1 according to ,davy's ideas1 this was amorphous leather4 ,against this1 it was urged that even the supposed #8tannate of gelatine' itself could not be a true chemical compound1 since the proportions of its constituents were considerably varied by changes in the strength of the solutions1 or by washing the precipitate with hot water2 and further1 that in chemical compounds1 the form was changed1 and no trace of the original constituents appeared in the compound2 while in leather apart from some change of color and properties1 the original fibrous structure remained unaltered4 8,this reasoning appears much less conclusive now than it did in ,knapp's day4 ,against the last objection guncotton may be quoted as an instance of profound chemical change with no alteration in outside appearance2 and it is recognized that1 especially among complex organic substances1 chemical reactions are rarely complete1 but that stable positions are reached1 so-called #8equilibria1' in which the proportion of changed and unchanged substance is dependent on concentration or other conditions2 and that therefore such a precipitate might well be a mixture of gelatine with a true gelatine tannate from which further portions of tannin might be dissociated by water4 8,with the clearing up of old difficulties1 however1 the conflict between chemical and physical theories has1 as is usually the case1 merely passed into a new phase4 ,years ago1 it was shown by ,linder and ,picton and others1 that liquids could be obtained which were not really solutions of ions or molecules1 but merely suspensions like that of clay in water1 or butter-fat in milk2 but so finely divided as to appear clear and transparent1 and pass through filters like true solutions4 ,later1 by means of the ultra-microscope their discrete particles have actually been made visible1 each of them consisting of many molecules of the suspended substance4 ,nevertheless1 these particles have many molecular properties1 possessing plus or minus electrical charges2 behaving like large ions under the influence of an electrical current2 and mutually precipitating and neutralizing each other when positive and negative are brought together4 ,such solutions are called #8colloid1' and those of gelatine and tannin are of the class1 so that it is now often said that the precipitation of gelatine by tannin1 and the fixation of tannin by gelatinous fibre are merely #8colloidal' and #8physical1' and not #8chemical' phenomena4 ,admitting the facts1 the question still arises whether the distinction between chemical and physical is not here one without a difference2 and whether between the purely ionized dilute solution of a salt and the coarsely granular clay suspension there is any point where a definite line of demarcation can be drawn4 ,the writer inclines to the view that there is not2 and that ionic and colloidal combinations are extreme cases of the same laws1 both physical1 and both chemical40 ,there are several methods which are used in tanning furs1 each having its peculiar characteristics and qualities1 and possessing individual advantages and disadvantages4 ,in order to be able to judge the merits of the various processes1 it is necessary to have a criterion which can serve as a basis of reference4 ,fahrion1 a recognized authority and investigator in this field1 gives a definition of leather which is usually accepted as a standard for comparison4 ,he says3 8,leather is animal skin1 which on soaking in water and subsequent drying does not become hard and tinny1 but remains soft and flexible2 which does not decay in the presence of cold water2 and which does not yield any gelatine on boiling with water40 ,while the requirements set forth in this statement are essential for leather1 and a compliance with them would also be desirable for tanned furs1 a somewhat less rigorous standard of conditions to fulfil is satisfactory for the general needs and purposes of furs4 ,the chief qualities which tanned furs must possess1 with particular reference to the leather side of the pelt1 are retention of softness and flexibility after being moistened by the furrier for manufacturing purposes1 and subsequent drying2 and freedom from a tendency to decay during this operation and thereafter4 ,if the furs are to be dyed1 the effect of the dyeing must also be considered1 and the tanning must be such as to enable the dyed furs to possess the above qualities4 ,the most important tanning processes employed for furs are the following3 #a4 ,salt-acid tan1 or pickle4 #b4 ,mineral tans4 #c4 ,chamois tan4 #d4 ,formaldehyde and similar tans4 #e4 ,combination tans4 #f4 ,vegetable tan4 #a4 ,,salt-,,acid ,,tan1 ,,or ,,pickle ,this is one of the most extensively used methods for tanning furs1 and is also very cheap and easily applied4 ,a typical formula for this tan is the following3 ,a solution of salt is prepared containing about #aj of common salt1 sodium chloride1 and to this is added #a_/b-c_/d ounce of sulphuric acid for each gallon of tanning liquor4 ,the proportions may be varied within certain limits1 but the figures here given are those which have proven successful in practise4 ,the solution should be made in a wooden or earthenware container1 free from any metal1 as it would be attacked by the acid4 ,the liquor is then applied to the flesh-side of the fleshed skins by means of a brush1 making sure to touch all parts of the pelt4 ,they are then placed in a pile and allowed to remain thus until tanned1 an operation which occupies a time ranging from a few hours to two or three days depending on the thickness of the skins4 ,when the corium has lost its translucence and has become of a milky-white color throughout the entire thickness of the skin1 as can be seen by viewing a cross-section1 the skin may be considered tanned4 ,in some instances1 where the hair of the fur can stand immersion without injury1 the skins are entered into the pickling solution and allowed to remain for #ab to #bd hours1 which is generally a sufficient time to tan them in this manner4 ,the acid of the pickle causes the skin to swell1 the salt then penetrating between the fibres of the corium1 and at the same time reducing the swelling of the skin4 ,the acid also neutralizes the alkaline products of decomposition which may form1 while the salt acts as a deterrent to the progress of the putrefactive processes4 ,when the skin is dried after tanning1 and stretched and finished1 a soft white leather is obtained which is permanent as long as it is kept dry4 ,it is the salt which causes the fibres of the skin to be completely differentiated and thus prevents their adhesion4 ,it is interesting to note that other acids besides sulphuric can be used for the pickle1 organic as well as mineral1 formic acid in #a_/d solution being especially effective and giving excellent results1 but is more expensive than the mineral acid4 ,a method1 which in principle is identical with the pickle1 but carried out in an entirely different manner1 is the lactic acid fermentation process1 or 8,schrot-beize0 as it is called in ,german4 ,the procedure is in general as follows3 8,the fleshed skins are placed on tables1 flesh-side up1 and covered with a layer of bruised barley grains1 or a mixture of #c parts of wheat bran and #b parts of rye flour4 ,then the head1 tail and legs are turned inward1 and the skins rolled up in little cushions1 hair-side out1 and placed in a vat4 ,when this is filled with the skins a solution of common salt is poured over them1 and they are allowed to remain thus in a moderately cool place for #bd hours4 ,after this time1 the skins are carefully unrolled1 so as not to remove any of the adhering solid materials1 and turning the skins hair-side inward1 they are laid flat together in pairs and placed in an empty vat4 ,after another #bd hours they are again unpacked and replaced in another vat1 care being taken each time to keep all the solid particles adhering to the flesh-side4 ,this operation is continued and repeated until the skins are properly tanned1 which takes from #aj to #ad days1 depending on the weather and the temperature4 ,the skins are then removed1 rinsed free of the tanning substances1 pressed1 dried and finished40 ,a somewhat modified form of this process is the so-called ,russian tan1 which is usually done in the following manner3 #e parts of bruised barley grains are mixed with ten parts of luke-warm water in a vat1 which is then covered up4 ,a small quantity of brewers' yeast is also added to aid in the fermentation4 ,as soon as the mixture develops a slight heat1 one part of fresh whey is added1 and the fleshed skins entered into the tanning liquor in which they remain for about #ab hours4 ,they are then tramped in the mixture so as to effect greater penetration1 and left until the tanning process is complete4 ,whey is the milk fluid left after the casein and most of the fat have been removed from the milk by coagulation1 and consists practically of a solution of all the milk-sugar or lactose1 and the lactic acid of the milk1 together with a small percentage of mineral salts1 and a slight amount of fat4 ,by fermentation1 the milk-sugar is converted into lactic acid1 which helps to effect the tan by swelling the skin4 ,the effectiveness of the fermentation processes depends to a considerable degree on the action of certain bacteria and yeasts4 ,bacteria are one-celled organisms belonging to the vegetable kingdom1 and some are so small as to be scarcely visible under a microscope1 while some indeed cannot be seen by any means1 their existence being inferred from their effects4 ,as they vary in size1 bacteria also vary in shape1 some being spherical1 others in the form of long1 thin rods1 while still others are of a spiral shape2 another common form is the dumb-bell shaped bacterium4 ,some types are provided with what are known as flagella1 which resemble fine hairs attached to the body of the organism1 and which enable it to move about actively in liquids4 ,the food of bacteria is always in liquid form1 as only in this condition can it be absorbed4 ,however1 some kinds of bacteria attack solid substances from which they obtain their nourishment1 but this is done in an indirect way1 by secreting certain fluids known as enzymes1 which dissolve or digest the material and convert it into a form that can easily be absorbed by the bacteria4 ,the enzymes are non-living chemical substances1 which possess the peculiar property of bringing about the chemical change of an almost indefinite amount of material upon which they act1 without themselves being in any way changed4 ,yeasts also act in a manner similar to the bacteria in causing various chemical changes1 particularly inducing fementations4 ,in the simple 8,schrot-beize10 the starch contained in the bran or barley grains is first converted to a soluble sugar by means of enzymes secreted by the bacteria which are always present4 ,this sugar then undergoes an acid fermentation1 with the formation of lactic and acetic acids1 due in this case to organisms known as the bacterium furfuris ,a and ,b4 ,the action of the ,russian tan is similar1 but quicker4 ,in this case1 the sugar is already present in soluble form1 and the yeast cells cause its fermentation with the production of lactic acid4 ,in both cases1 the acids as they form swell and loosen up the skin fibres slowly1 the salt penetrating between them1 and keeping them separated on drying4 ,both methods give results which are equally good1 but by the ,russian tan the skins acquire a disagreeable odor1 which makes this method of dressing objectionable4 ,the lactic acid fermentation processes have an advantage over the pickle1 in that the slow formation of weak organic acids with their gradual action produce a softer leather1 with a gentler #8feel1' the presence of the flour and the grains of the tan1 aside from their tanning action1 contributing to the fullness and softness of the leather4 ,there is also less likelihood of the leather being subsequently affected by the presence of the acid in it1 as lactic and acetic acids are much less injurious than sulphuric acid to leather4 ,these disadvantages of the pickle can to a large degree1 be overcome without any great difficulty4 ,on the other hand1 the matter of the length of time of the tanning process1 shows the acid pickle at a great advantage1 and so1 especially for furs other than those obtained from sheep and goats1 the pickle is in most cases used as the principle method of tanning4 ,in ,austria1 ,russia1 and to a certain extent in ,germany also1 the 8,schrot-beize0 is still considerably employed1 chiefly for dressing sheep and lamb skins4 ,the dressing of the various kinds of ,persian lambs1 caraculs1 astrachans1 etc41 in the native center of the industry in ,buchara and surrounding districts1 is also a 8,schrot-beize10 barley1 rice flour or rye flour1 and salt water being used to prepare the skins1 the manipulations being essentially the same as those described above1 although carried out in cruder and more primitive fashion4 #b4 ,,mineral ,,tans ,the basis of the tanning of furs by means of solutions of mineral compounds is the fact that the basic salts of certain metals are capable of producing leather4 ,it has been found that compounds of aluminum such as alum or aluminum sulphate1 or any other soluble neutral salt of aluminum1 possess tanning powers4 ,other metals which are capable of forming salts of the same type are also endowed with the quality of converting skin to leather under suitable conditions1 chromium and iron being the most important metals in this connection4 ,chemically these metals all belong to the same group1 and have properties which are very similar in many respects1 the characteristic of most importance for tanning purposes being the quality of forming soluble basic salts by the addition of alkalies or alkaline carbonates to solutions of their neutral salts1 or in certain instances simply by the action of water upon these neutral salts4 ,by neutral salts are meant those in which the metallic content is combined with the normal proportion of acid2 while basic salts are those in which the acidic portion is present in less than the normal ratio1 being partially replaced by a hydroxide group4 ,when the acid part of the salt has been entirely replaced in this way1 the compound is called a hydroxide or hydrate of the metal4 ,between the neutral salt and the hydroxide several different basic salts are possible1 some being soluble1 while others are insoluble4 ,if into a solution containing a basic salt of either aluminum1 iron or chromium a skin be entered1 a part of the basic salt will be precipitated on it in insoluble form4 ,inasmuch as neutral salts of these metals when dissolved in water split up to a small degree1 into free acid and soluble basic salt1 a skin immersed in such a solution will also absorb the basic salt in an insoluble form4 ,upon these facts in general1 depends the action of the mineral tans used in tanning furs4 ,a4 ,alum ,tan ,the alum tan is one of the oldest methods of producing leather1 being employed by the ,romans about two thousand years ago1 and it is believed1 by the ,egyptians at a much earlier period4 ,its extensive use in ,europe1 however1 dates from the time of the conquest of ,spain by the ,moors1 who introduced the process4 ,at the present time1 rabbits and moles are tanned by this process1 as are also at times other furs such as muskrats1 squirrels1 sables1 martens1 etc41 when a better tan is desired than that produced by the pickle4 ,ordinary alum1 which is a double sulphate of aluminum and potassium1 and aluminum sulphate are the chief compounds used for this tan4 ,in recent years1 the aluminum sulphate has to a considerable degree replaced the alum for tanning1 inasmuch as it can be cheaply obtained in a sufficiently pure form1 and contains about one and one-half times as much active aluminum compound as does alum4 ,while the aluminum salt can be used alone for tanning1 it produces a stiff1 imperfect leather1 so salt is always added4 ,the ratio of the salt to the aluminum sulphate or alum can vary within rather wide limits1 the mixtures used in practise ranging from one part of salt to four parts of the aluminum compound1 up to equal parts of both1 or even in some formulas1 a greater proportion of salt than of the other constituent4 ,ratios which are most common are four of alum to three of salt1 or two of alum to one of salt4 ,when aluminum sulphate is dissolved in water1 a small part of it splits up into a soluble basic salt and an equivalent amount of free acid4 ,the reaction may be shown as follows3 ,al7,,so7 #b;,h,o ,al7,,so77,,oh7 ,h,,so aluminum water basic aluminum sulphuric sulphate sulphate acid ,when a skin is entered into such a solution1 the free acid is absorbed1 causing a swelling of the pelt4 ,while this is taking place1 a further quantity of the neutral aluminum salt splits up into more basic salt and free acid4 ,at the same time the basic aluminum sulphate is also taken up by the skin1 probably attaching itself to some of the acidic groups contained in the skin substance1 in a manner analogous to the combination of the acid with the basic groups of the skin substance4 ,a point is reached1 however1 when the skin is no longer able to take up more of the basic salt1 for the presence of the acid undoubtedly acts as a deterrent4 ,the skin1 if dried after such a treatment contains a small amount of aluminum1 which is insufficient to tan the pelt properly1 and as a result this comes out in an undesirable and quite useless condition4 ,if to the solution of the aluminum sulphate salt is added1 a different result is obtained4 ,to a certain extent the salt acts here as in the pickle4 ,the skin on absorbing the free acid of the solution naturally swells1 but the salt reduces this swelling1 and at the same time1 by penetrating between the fibres and dehydrating them1 produces a leather as in the pickle4 ,in addition1 the presence of the salt enables a greater amount of basic aluminum sulphate to be formed1 and thus a greater quantity is taken up by the skin4 ,on drying and stretching after such a treatment1 a soft1 flexible and stretchable leather is obtained4 ,the number of formulas for tanning furs by this process is legion1 the principle being the same in every instance1 and mixtures of salt and alum or aluminum sulphate form the basis of the various tans4 ,following are a few typical formulas1 which have been found to be of practical value3 ,a solution is prepared by dissolving #g4e lbs4 of alum and #c lbs4 of common salt in #bj gallons of water4 ,when cool1 the clean1 fleshed skins are entered1 being paddled or drummed for a short time and then allowed to remain until tanned4 ,by this method the hair also takes up some of the alum1 and if the skins are to be dyed1 unevenness may result4 ,in order to avoid this1 the tanning may be effected by brushing a stronger solution on the pelt4 ,a mixture of #d lbs4 of alum and #c lbs4 of salt1 dissolved in #h gallons of water1 and made into a paste by the addition of #d lbs4 of flour1 is applied to the flesh-side of the skins4 ,these are then placed in pairs1 flesh-side together1 and allowed to remain in a pile until tanned4 ,sometimes a second application is given4 ,the flour may be omitted1 but it serves to cause the tanning mixture to adhere better to the skins4 ,still another method is the following3 ,into the flesh of the moist1 fleshed skins is rubbed a mixture of two parts of dry powdered alum with one part of salt4 ,after allowing time for it to be absorbed1 another application is given1 rubbing in well1 and especially treating the thick parts4 ,the pelts are then folded up1 or rolled together1 flesh-side in1 and placed in a vat or tub1 which is covered up to prevent drying4 ,they are left so until tanned1 as shown by examination and test4 ,they are then rinsed1 hydro-extracted and dried1 and after stretching and finishing1 a soft1 white1 pliable leather is obtained4 ,b4 ,chrome ,tan ,by using chrome alum instead of ordinary alum1 together with salt1 skins can be tanned1 but the leather formed is not altogether satisfactory4 ,the basic principle here is the same as in the alum tan1 depending on the formation of soluble basic chrome sulphates in the solution of a neutral sulphate4 ,the method employed at the present time1 the so-called one-bath process as distinct from the two-bath process1 which cannot be applied for tanning furs1 involves the production of the basic chrome sulphate by the addition of an alkali or an alkaline carbonate to the solution of the neutral salt4 ,it was ,prof4 ,knapp who first published this process as early as #aheh2 but it was not until #ahic that it was shown to be of practical value1 and was then patented in this country by ,martin ,dennis4 ,since that time it has been in general use with but slight modifications4 ,the chrome tan is used only to a limited extent in the tanning of furs1 the method requiring very careful treatment and accurate supervision during the various stages of the process1 and the leather coming out colored a pale-blue-green tint1 which for some purposes is objectionable4 ,in some plants ponies and rabbits are tanned with chrome2 and when the skins are to be dyed by means of certain coal tar dyes1 they have to receive a chrome tannage4 ,the leather produced by a chrome tan is very durable1 and possesses great resistance to the action of water4 ,any salt of chromium1 with either mineral or organic acids1 can be used1 but chrome alum is the one most commonly employed4 ,if a skin is entered directly into a solution of a chrome salt made basic with an alkali1 the precipitation of the insoluble basic salt will take place very rapidly1 and the tanning will be only superficial4 ,the procedure is therefore first to treat the skins with a chrome solution which forms only small quantities of the basic salt4 ,after the skins are impregnated with the solution1 this is made basic1 so that the real tan will take place within the skin tissues among the fibres of the corium4 ,a common formula is the following3 #e lbs4 of chrome alum are dissolved in #aj gallons of water4 ,the skins are entered into the solution at about #gj ,f4 and paddled for about #b hours1 or drummed for one hour4 ,then a solution of three pounds of washing soda is added slowly to the liquor which is then stirred up well1 and the skins drummed or paddled again for an hour or two1 and then left in the liquor for #ab to #bd hours till completely tanned4 ,the skins are rinsed1 and washed in #a_/b solution containing #b_/c of the weight of the skins of borax4 ,the pelts are then well washed in clean water1 hydro-extracted and dried4 ,c4 ,iron ,tan ,tanning by means of iron salts has thus far been merely a matter of scientific interest and has not found any practical use4 ,the principle involved is identical with that of the preceding mineral processes4 #c4 ,,chamois ,,tan ,the chamois dressing1 as previously noted1 is undoubtedly the oldest method of preparing leather from skin1 the various fat-containing substances derived from animals1 fish1 birds1 etc41 being used for the purpose4 ,the chief object of the fat was to coat the fibres of the skin1 thus preventing their adhesion1 and at the same time rendering them resistant to water4 ,in the true chamois tan1 the fat seems to have also a chemical function in contradistinction to the other which is merely physical or mechanical4 ,for1 if skins tanned by the chamois process be treated with a weak solution of an alkali1 all the fatty materials should be removed thereby1 but this happens only to a small extent1 the pelt retaining its softness and pliability1 and the other characteristic qualities of leather1 indicating that the fat is combined intimately with the skin substance in a permanent fashion4 ,in tanning furs1 various oils and fats are used1 but not all are capable of producing a chamois tan4 ,among the fatty materials are mineral oils1 and vegetable and animal oils and fats4 ,mineral oils are the distillation products of petroleum1 partially liquid1 and partially solid4 ,being inert substances1 they have no tanning effect1 but serve merely as water-proofing or fattening materials4 ,except for their oily nature they have nothing in common with fats1 being quite unaffected by solutions of alkalies or of acids4 ,vegetable and animal fats and oils are1 when pure1 neutral substances formed by the combination of fatty acids with glycerine4 ,they possess the property of saponification1 that is1 of forming a soap when treated with an alkali1 the soap being the alkaline salt of the fatty acid4 ,under certain conditions1 the fat can be split up into free fatty acid and glycerine by the action of acids1 or even water alone4 ,some fats on long standing1 split up in this way spontaneously in the presence of moist air4 ,as a general rule1 those fats which exhibit this property to a marked degree are affected by contact with the air1 due to the absorption of oxygen which reacts chemically with the fats1 forming what are known as oxy-fatty acids1 usually less soluble1 and having a higher melting point than the original fats4 ,vegetable and animal fatty materials are classified on the basis of this phenomenon of absorbing oxygen from the air1 those possessing this quality to a great degree being called 8drying oils10 others being 8partially drying10 or 8non-drying40 ,olive oil1 castor oil1 cocoanut oil and cottonseed oil are examples of non-drying or partially-drying vegetable oils1 linseed oil being the most important drying-oil in this class4 ,tallow1 lard1 butter-fat1 neats-foot oil are non-drying animal fats1 the drying oils being seal oil1 whale oil1 and cod-liver oil4 ,illustration3 ,,fig4 #h4 ,,tramping ,,machine ,,or 8,,kicker40 7,f4 ,blattner1 ,brooklyn1 ,new ,york47 ,for tanning purposes1 this property of absorbing oxygen is important1 because only with drying oils can a true chamois tan be obtained1 non-drying oils acting like mineral oils only as water-proofing materials4 ,the details of the chamois process are not quite clear1 there being considerable difference of opinion on the matter4 ,but all the studies on the subject tend to prove that there are at least two phases to the process3 first1 the mechanical covering of the fibres with the fat1 this property being common to all fats or oils which may be used2 and second1 the combination of the fat with the skin in some chemical way1 as a result of the oxidation of the fat1 a characteristic found only in the drying oils4 ,during the oxidation of the fats1 the glycerine in them is converted to acrolein or acryl-aldehyde1 which also aids the tanning4 ,it was at one time supposed that the tanning action was due to this aldehyde alone1 but a chamois tan can be made with fatty substances from which all the glycerine has been removed4 ,the evidence on this question1 however1 is not quite conclusive4 ,in general1 the procedure of the chamois tan is as follows3 ,the hydro-extracted1 fleshed skins are rubbed on the flesh-side with a good quality of seal-oil4 ,they are then folded up1 and put into a #8kicker1' where they are tramped for two or three hours to work in the oil4 ,the kicker is a machine such as shown in ,fig4 #h consisting of a receptacle for the skins1 and two wooden hammers which work up and down mechanically1 turning and pounding the skins4 7,as many as #ajjj-aejj skins of the size of musk-rats can be worked at one time in such a machine47 ,the pelts are then taken out and hung up in a warm room for several hours1 considerable oxidation taking place4 ,another coat of oil is then applied1 which is again tramped in1 and the skins are hung up once more and exposed to the air to cause the oil to oxidize4 ,after the skins are sufficiently tanned they are rinsed in a weak soda solution to remove the excess oil1 washed and dried4 ,when skins with fine hair such as marten1 sable1 mink1 etc41 receive a chamois tan1 they are not tramped in kickers as the delicate top-hair will be broken1 and the value of the skin thereby reduced4 ,instead they are placed in small drums1 together with metal balls of varying sizes and weights depending on the particular fur treated1 and the oil is worked in by rotating the drum4 ,such a ball-drum1 as it is called1 is shown in ,fig4 #i4 ,illustration3 ,,fig4 #i4 ,,ball ,,drum4 7,f4 ,blattner1 ,brooklyn1 ,new ,york47 ,in conjunction with the chamois tan may be discussed the process of oiling1 inasmuch as the method of application and the effect are both similar to the chamois tan up to a certain point4 ,it is customary to treat skins tanned by any other method but the chamois process1 with some oil in order to render them more impervious to water4 ,the greatest variety of oils and fats can be used1 the action in most cases being simply the mechanical isolation of the skin fibres by such a substance1 thus corresponding to the first or physical phase of the chamois tan4 ,the chemical phase1 if it takes place at all1 is usually slight1 and is merely incidental4 ,oiling is generally applied either before drying after tanning1 or after drying1 the oiled skins being placed in a kicker and tramped to cause the oil to penetrate4 ,in some instances the oiling material is put in the same mixture as the tanning chemicals1 and the tanning and oiling are effected simultaneously4 ,among fatty substances used for oiling are mineral oils1 such as paraffine oil1 and vaseline2 animal fats1 like train oils1 butter1 egg-yolk1 glycerine1 neats-foot oil2 vegetable oils1 like olive oil1 castor oil1 cottonseed oil2 also sulphonated castor oil and sulphonated neats-foot oil4 ,these may be used singly or in various mixtures1 an emulsion of an oil and a soft soap also being frequently employed4 #d4 ,,formaldehyde ,,tans ,formaldehyde has proven to be of great value in the tanning of furs1 usually in conjunction with other processes4 ,formaldehyde is a gas with a strong1 irritating odor1 and its #dj solution1 which is the customary commercial form1 also possesses this quality4 ,when skins are treated for several hours with a very dilute solution of the commercial product1 a leather is obtained which combines the properties of the alum tan and the chamois tan4 ,moreover1 in the majority of observed cases1 where furs have been tanned with formaldehyde1 the skins seem to acquire a certain immunity to the attacks of vermin and moths4 ,although the skins do not in any way retain the odor of the formaldehyde1 nevertheless these destructive agents seem to be repelled4 ,numerous processes have been devised which use formaldehyde in connection with other substances for tanning4 ,thus in a ,german patent is described a method involving the alternate or simultaneous treatment of pelts with solutions of formaldehyde and alpha or beta naphthol4 ,both the formaldehyde and the naphthol exercise tanning actions1 but the process is not used in practise4 ,in #aiaa1 ,stiasny1 a well-known leather chemist produced a synthetic substance by the condensation of formaldehyde with a sulphonated phenol1 forming an artificial tannin4 ,this chemical1 called 8,neradol ,d10 exhibits many of the properties characteristic of true tannins1 although in no way related by structure and composition4 ,by the use of 8,neradol ,d0 a soft1 white and flexible leather is obtained1 and it is therefore a suitable tanning material for furs4 #e4 ,,combination ,,tans ,in many instances more than one method is employed in tanning the furs1 and in this way what is known as a combination tan is produced4 ,while the various individual processes described give more or less satisfactory results by themselves1 they generally possess some features1 which for certain purposes may be undesirable1 and which can be eliminated or considerably reduced by using other processes at the same time or subsequently4 ,some of the combination methods are1 pickle with chrome tan1 alum tan with chrome tan1 and formaldehyde tan with pickle1 mineral tan or chamois tan4 ,by means of such combinations various qualities of tanned furs can be obtained1 and if it is desired to produce a pelt having certain special characteristics1 this can be brought about by combining two or more standard methods4 ,some illustrations of combined tannages are the following3 ,alum-chrome tan4 ,the skins are tanned by the regular alum process1 then the constituents of the chrome tan are dissolved directly in the same bath1 and the chrome tan is effected as usual4 ,chrome-formaldehyde tan4 ,to the regular chrome tan solution is added #a_/b lb4 of formaldehyde for every #aj gallons of chrome liquor4 ,the rest of the process is as ordinarily4 #f4 ,,vegetable ,,tans ,in practise1 the vegetable tanning matters are not used for furs1 although in some special instances gambier cutch may be employed occasionally with some other tan4 ,however1 many of these tannins also have dyeing properties1 and are used in dyeing the furs4 ,in this connection it must be mentioned that furs dyed with these materials also receive a vegetable tan1 which improves the quality of the leather to a considerable extent4 ,comparison of ,the ,various ,tanning ,methods ,in choosing a method for tanning any particular kind of fur1 several factors must be considered4 ,the nature of the pelt1 insofar as it is weak or strong2 the time1 labor and cost of materials required by the tanning process2 the effect on the leather of the different dyes and chemicals used in dyeing1 if the skin is to be dyed1 are a few of the points requiring attention and consideration4 ,for furs which are only to be dressed1 a simple tan like the pickle will suffice in most cases4 ,special instances1 such as the rabbit and mole already mentioned1 and a few other furs are tanned by the alum method4 ,the pickle is undoubtedly the cheapest and simplest method of tanning skins1 and yields a soft1 white leather which is permanent as long as it is kept dry4 ,if it is put into water1 about #be of the salt contained within the pelt dissolves out1 and the acid present swells up the tissues4 ,if the skin is dried in this condition1 it will come out hard and brittle1 tending to crack very easily4 ,by treating the leather before drying with a strong salt solution1 a good deal of the extracted salt will be replaced1 and on drying and stretching1 it will work out soft4 ,skins tanned by the 8,schrot-beize0 are affected by water in quite the same manner as the pickled skins4 ,the alum tan gives a leather similar to that produced by the pickle1 but with the advantage that the skins possess greater stretch and flexibility4 ,in its resistance to water1 the alum-tanned pelt is quite as susceptible as the other4 ,as a general rule1 the skin absorbs about #f of its weight of alum from the tanning solution1 but gives up three-quarters of this when it is soaked in water1 producing on drying1 a hard1 stiff leather4 ,the chrome tan is especially impervious to water1 easily resisting temperatures of #hj ,c41 and even boiling water4 ,it is employed to only a limited extent on account of the special effort and care required to obtain satisfactory results1 also because the pelt acquires a pale blue-green color which is not desired on dressed skins4 ,the chamois tan1 and some of the combinations of the formaldehyde tan with the other methods1 give very soft1 flexible leathers which possess a sufficiently great resistance to the effects of water and heat4 ,in tests made to determine the best working temperatures for dyeing skins dressed by the salt-acid tan1 and for skins dressed by the chamois process1 some very interesting facts were brought out4 ,these two tans were chosen because they represent opposite extremes1 the salt-acid tan usually giving the poorest results1 and the chamois tan giving the best results in practise in dyeing4 ,other methods1 except the chrome1 range between these two4 ,the procedure in these experiments was to treat the skins at ordinary temperatures in water1 or dilute solutions of the various chemicals and dyes usually employed in dyeing1 and then heat these solutions until the leather just began to shrink and shrivel up4 ,this point1 called the shrinking point 7,s4,p471 gave the temperature to which the skins could be subjected in the given solution without danger to the pelt4 7,the experiments and observations were made by ,erich ,schlottauer1 while director of a large ,german fur dressing and dyeing plant74 ,the first observation made was that different furs tanned by the same process were affected differently in the same solutions4 ,thus in plain water1 three furs1 all tanned by the acid-salt tan1 had shrinking points varying by several degrees2 similarly with two different furs tanned by the chamois process1 there was a variation in the shrinking point of two degrees4 ,the explanation of this discrepancy among the different skins may be that there was a slight difference in the conditions under which they were tanned1 experiments showing that a maximum difference of #d ,c4 may exist among skins tanned by the same process1 but not under the same or identical circumstances4 ,another reason for the variation may be the fact1 that some skins are more greasy than others1 and are thus more resistant to the effects of water or of some chemicals4 ,the furs with the higher shrinking points in water were those which naturally are more greasy than the others4 ,weak solutions of acids tend slightly to lower the shrinking point1 while weak solutions of alkalies appreciably raise it1 in both chamois-tanned and salt-acid-tanned skins4 ,solutions of dyes and mordants as a general rule increase the resistance of the skin to heat1 varying quantities of these substances having no1 or little different effects on the shrinking points4 ,previous treatment of the leather with some oil considerably raises the shrinking point of the pelt4 ,formaldehyde effects a great increase of the resistance of the skins to heat1 especially with chamois-tanned furs4 ,the experiments in this case were made by first treating the skins in the weak formaldehyde solution1 and then determining the shrinking point in plain water4 ,two skins1 both dressed by the 8,schrot-beize10 a ,persian lamb and an astrachan1 after dyeing had shrinking points almost #aj degrees higher than when undyed4 ,the extra tannage which the skins received from the tannins used in the dye mixtures for these furs1 accounts for this increased resistance to heat4 ,the following tables give the observed figures in the different experiments3 ,,table ,i ------------------------------------- ,a ,b ,c ,s4,p4 ,s4,p4 ,s4,p4 ------------------------------------- ,salt-acid ,tan ,c4 ,c4 ,c4 ,australian ,opossum #df #eh #de ,marmot #de #ej #db ,skunk #dg #ef #dc ,chamois ,tan ,mink #eb #fa #de ,muskrat #ej #eh #db ------------------------------------- ,a--,water ,b--,water plus #a ,ammonia 7s4g4 #j4iaj7 ,c--,water plus #a ,sulphuric acid 7#ff ,beaum7 ,,table ,,ii ------------------------------------- ,a ,b ,c ,s4,p4 ,s4,p4 ,s4,p4 ------------------------------------- ,salt-acid ,tan ,c4 ,c4 ,c4 ,australian ,opossum #ec #eb #ed ,chamois ,tan ,mink #ei #ei #ei ------------------------------------- ,a--#ajjj c4c4 water plus #dj c4c4 ,peroxide plus #e c4c4 ammonia ,b--#ejj c4c4 water plus #b grams ,ursol ,d 7,para-phenylene-diamine7 ,c--#ejj c4c4 water plus #e grams ,ursol ,d ,,table ,,iii ---------------------------------------- --- ,a ,b ,c ,d ,s4,p4 ,s4,p4 ,s4,p4 ,s4,p4 ---------------------------------------- --- ,salt-acid ,tan ,c4 ,c4 ,c4 ,c4 ,australian ,opossum #ea #ea #ec #ef ,chamois ,mink #ei #ei #fa #fb ---------------------------------------- --- ,a--#ejj c4c4 water plus #e grams ground nut-galls ,b--#cjj c4c4 water plus #b grams pyrogallic acid ,c--#ejj c4c4 water plus #b grams potassium bichromate ,d--,water1 after treating leather with rapeseed oil ,,table ,,iv ---------------------------------------- --- ,a ,b ,c ,d ,s4,p4 ,s4,p4 ,s4,p4 ,s4,p4 ---------------------------------------- --- ,salt-acid ,tan ,c4 ,c4 ,c4 ,c4 ,australian ,opossum #di #di #ee #ej ,chamois ,tan ,mink #ei #fg #fi #gj ---------------------------------------- --- ,a--#ejj c4c4 water plus #e c4c4 formaldehyde for #a hour ,b--#ejj c4c4 water plus #e c4c4 formaldehyde for #ab hours ,c--#ejj c4c4 water plus #aj c4c4 formaldehyde for #c hours ,d--,as in ,c1 but treated with #ejj c4c4 water plus #e c4c4 ammonia1 instead of water alone4 ,,table ,v ------------------------- ,a ,b ,s4,p4 ,s4,p4 ------------------------- ,c4 ,c4 ,persian ,lamb #dd #ed ,astrachan #dg #ee ------------------------- ,a--,before dyeing ,b--,after dyeing ,as a result of these experiments it may be concluded that the maximum temperature for drying salt-acid tanned skins should be #dj ,c41 while for chamois tanned skins the temperature may be permitted to reach #de ,c4 without any danger of the leather being affected4 ,moreover1 in the case of pickled skins1 the matter of extraction of the tanning agent1 as well as that of the leather becoming 8burned0 may be effectively counteracted by brushing some oil or fat on to the leather side before dyeing the pelt4 ,the shrinking points of skins dressed by the various tanning methods are constant within certain limits1 depending on the nature of the skin and on the conditions of tanning1 and it is possible by observing the shrinking point1 in conjunction with other characteristics of a given pelt1 to determine what method of tanning was used4 ,,chapter ,,vi ,,fur ,,dressing ,,drying ,,and ,,finishing ,one of the most important operations of all the fur dressing processes is the drying of the skins4 ,for even when all the previous steps have been successfully completed1 there is still a great possibility of the skin being injured if the drying is not properly and carefully carried out4 ,the essential requirements for good drying are proper temperature1 uniformity and rapidity4 ,the leather part of the fur cannot1 in the moist state1 resist temperatures exceeding about #de centigrade1 for when dried1 the skin turns out hard and stiff1 and cracks easily4 ,the furs must therefore be dried at an initial temperature of #be to #cj centigrade1 and as the moisture is gradually removed1 the temperature may be raised1 for the less water that remains in the pelt1 the less is the leather affected by the heat1 and the more difficult is the removal of its aqueous content4 ,if the drying process is not a uniform one1 that is1 if all the skins in a lot are not subjected to the same drying conditions1 then after the drying has proceeded for a certain time1 some skins may be quite dry while others are not1 or there may be as many different degrees of dryness as there are skins drying4 ,there is also the possibility of great variation in the amount of moisture removed from different parts of the same skin4 ,such a state of affairs requires an extra expenditure of time1 labor and heat power in order to get the whole lot of furs into a more or less uniform condition4 ,moreover in some kinds of furs1 especially those with thick skins1 when the drying is not even1 there is danger of the epidermal layer drying away from the corium1 and subsequently peeling and cracking4 ,uniformity of drying requires the maintenance of a reasonably constant temperature equally distributed throughout all parts of the space where the drying is done1 so that all the furs may be dried under the same conditions4 ,rapidity of drying is desirable not only because it is beneficial to the condition of the pelt1 but also from the point of view of practical business economy4 ,the space occupied by the drying should be as small as possible compatible with the volume of work1 and with the efficiency of operation4 ,slow drying involves the use of much space to take care of all the skins to be dried1 or an accumulation of pelts ready to be dried1 neither of which conditions is efficient or desirable4 ,it was formerly the general custom1 still practised in some establishments1 to dry the skins by hanging them up1 leather-side out on lines in a large room or loft1 the heat being usually supplied by steam pipes4 ,such a procedure occupied often as long as two or three days to get complete drying1 involved a great deal of labor1 and the results were far from uniform4 ,in fact1 in order to get the skins more nearly equable1 it was necessary to subject them to an additional operation4 ,this usually consisted of rotating the skins in a closed drum for several hours1 the constant intermingling of the pelts in contact with each other causing any moisture left in them to be evenly distributed throughout the whole lot4 ,the skins1 by this process also are rendered somewhat softer and more flexible1 but by drying under proper conditions the entire extra operation can be dispensed with1 the furs coming out quite as soft and flexible without the drumming4 ,a great improvement was the adoption of large fans to circulate the heated air in the loft1 thereby approaching more nearly an even temperature4 ,more modern devices have1 however1 been developed1 whereby drying can be effected in the most uniform manner1 with perfect control of temperature1 and requiring the least possible consumption of space1 time1 labor and power4 ,a typical arrangement consists of a large closed chamber1 generally constructed of steel1 and divided into several compartments each of which may be operated independently of the others4 ,air1 heated over suitably located steam pipes to the required temperature1 is forced through the various compartments by means of fans operated by power4 ,the conditions may be varied in each compartment1 as to temperature or humidity1 both of which can easily be regulated1 or all the compartments may be used together as one unit4 ,the skins are hung up on rods or lines in the compartments1 or on special frames for the purpose1 which are then entered into the compartments and the doors shut4 ,the dry1 heated air is forced to pass over the skins1 and takes up their moisture4 ,at the further end of the drying chamber is another fan which removes the moisture-laden air after it has done its work4 ,the drying is effected in from #f to #bd hours1 and all skins are obtained in the same condition1 for the process is quite uniform and regular4 ,within recent years there has been evolved a highly efficient and economical drying equipment1 based on a somewhat different principle than underlies any of the foregoing methods4 ,the conveyor type of dryer1 as it is called1 is admirably suited to the needs of the fur dressing and dyeing industry1 and is undoubtedly superior to any of the previous systems of drying furs1 in that it affords an enormous saving of space1 time1 labor and power1 and gives greater uniformity and presents better working conditions4 ,illustration3 ,,fig4 #aj4 ,,diagrammatic ,,views ,,of ,,conveyor ,,dryer4 a4 ,,side ,,view2 b4 ,,end ,,view4 7,proctor ,schwartz1 ,inc41 ,philadelphia47 ,the conveyor dryer consists essentially of a steel enclosure1 through which the skins pass on horizontal conveyors4 ,where special insulation is necessary1 asbestos panels are used to line the enclosure1 making the dryer absolutely fireproof1 and enabling the maximum utilization of heat4 ,in the middle of the dryer are located the steam coils which furnish the heat1 and in many instances exhaust steam can be used as the source of heat4 ,figure #aj shows diagrammatically the arrangement and operation of the conveyor type of dryer4 ,the enclosure is divided into several compartments1 in each of which a different condition of temperature and humidity is maintained1 the temperature being closely and accurately regulated by an automatic control1 and once the dryer has been set for any condition1 all skins will be dried exactly the same1 regardless of weather or season4 ,illustration3 ,,fig4 #aa4 ,,conveyor ,,dryer4 7,proctor ,schwartz1 ,inc41 ,philadelphia47 ,the skins to be dried are placed on poles which in turn are set on the horizontal conveyors as in ,fig4 #aa4 ,as the skins pass through the compartments1 large volumes of air1 heated to the required temperature over the steam coils1 are circulated among the skins by means of the fans4 ,exhaust fans1 properly placed1 remove a certain quantity of moisture-laden air when it has accomplished its full measure of work4 ,when the skins on the conveyors have passed the full length of the dryer1 they are entirely dry1 and are then removed from the poles4 7,fig4 #ab74 ,the time required for drying varies according to the nature of the fur from #a-b hours to #f-h hours4 ,in tests made to determine the relative efficiency of the conveyor type of dryer as against the old 8loft0 method1 it was found that there was a saving of over #ej in power1 and of #he in floor space1 as well as a great saving of labor1 when the conveyor system was used1 the number of skins dried in a given period of time being the same in both cases4 ,the advantages of the new method are easily apparent1 and the saving is sufficiently great with large lots of furs1 to make an appreciable difference in the final cost of dressing4 ,if the skins have been dried by a modern drying system they all come out in a uniform condition1 and are ready to go on immediately to the next operation4 ,if1 however1 a form of the 8loft0 method of drying has been used1 it is customary to subject the skins to an additional process4 ,the dried pelts are put in drums with damp sawdust1 and drummed for a short time in order to get them into the proper condition4 ,the drumming is essential for the purpose of equalizing the condition of the pelts1 some being drier than others1 and as a consequence of the contact with the moist sawdust1 they are all brought to the same degree of dryness4 ,as a result of this operation also1 the skins become considerably softened4 ,illustration3 ,,fig4 #ab4 ,,delivery ,,end ,,of ,,conveyor ,,dryer4 7,proctor ,schwartz1 ,inc41 ,philadelphia47 ,then if the pelts have not been previously oiled during the tanning process1 or prior to the drying1 they receive this treatment now4 ,the oil or fat is applied to the leather side of the furs1 which are then placed in the tramping machine for a short time in order to cause the oil to be forced into the skin4 ,the fibres of the corium thus become coated with a thin layer of fatty material1 which contributes greatly to the softness and flexibility of the pelt1 and increases its resistance to the action of water1 and also1 in certain instances a partial chamois tan is produced1 thereby improving the quality of the leather4 ,illustration3 ,,fig4 #ac4 ,,stretching ,,machine ,,for ,,cased ,,skins4 7,reliable ,machine ,works1 ,evergreen1 ,l4 ,i47 ,the skins are now returned to the work bench1 and subjected to the stretching or 8staking0 process4 ,this consists in drawing the skin in all directions over the edge of a dull blade1 which is usually fixed upright in a post with the edge up4 ,or1 the stretching may be done on the fleshing bench1 substituting a dull blade for the fleshing knife4 ,recently staking machines are being used in the larger establishments1 the work being done much more quickly and efficiently4 ,as a result of this operation1 the leather becomes very soft and flexible1 every bit of hardness and stiffness being eliminated1 and the skins receive their maximum stretch1 thereby giving the greatest possible surface to the pelage4 ,this not only helps to bring out the beauty of the hair1 but is also a decided advantage from the economic point of view1 as a considerable saving of material is effected in this way1 sometimes even to the extent of twenty-five per cent4 ,cased skins are stretched in a somewhat different manner1 by means of stretching irons4 ,these consist of two long iron rods joined by a pivot at one end4 ,the skins are slipped on to the irons1 which are then spread apart1 and in this way the skins are stretched and softened4 ,a machine which does this work very efficiently is shown in ,fig4 #ac4 ,the skin is drawn onto the stretching arms1 in this case made of bronze1 which are then forced apart by pressing on a pedal4 ,when properly stretched to the maximum width in all directions possible1 and thus thoroughly softened1 the skin can easily be reversed1 that is1 turned hair-side out4 ,as many as #fjjj skins can be stretched1 or #djjj to #ejjj skins stretched and reversed by one man in one day on such a machine4 ,illustration3 ,,fig4 #ad4 ,,fur ,,beating ,,machine4 7,s4 ,m4 ,jacoby ,co41 ,new ,york47 ,the pelts are then combed and beaten4 ,in smaller plants these operations are done by hand1 but suitable machines are being employed4 ,in order to straighten out the hair1 it is combed or brushed4 ,then in order to loosen up the hair1 and to cause it to display its fullness1 the furs are beaten4 ,this process is also done by hand in some establishments1 but up-to-date places use mechanical devices for this purpose4 ,a type of machine which has proven very successful1 and is enjoying considerable popularity is shown in ,fig4 #ad4 ,these machines are also made with special suction attachments which remove all dust as it comes out of the beaten skin1 thereby making this formerly unhealthful operation thoroughly sanitary and hygienic4 ,the final process is drum-cleaning4 ,this operation is intended specifically for the benefit of the hair part of the fur1 and is very important inasmuch as the attractive appearance of the fur depends largely upon it4 ,the drum1 such as is shown in ,fig4 #ae is generally made of wood1 or sometimes of wood covered with galvanized iron4 ,the skins together with fine hardwood sawdust are tumbled for #b to #d hours1 or sometimes longer4 ,occasionally a little asbestos or soapstone is added to the sawdust2 for white1 or very light-colored skins1 gypsum or white sand is used1 either alone1 or in admixture with the sawdust2 and for darker skins1 graphite or fine charcoal is sometimes added in small quantities4 ,the drum-cleaning process polishes the hair1 giving it its full gloss and lustre1 and at the same time absorbing any oil or other undesirable matter which may be adhering to the hair as a result of the washing and tanning processes4 ,any soap1 or traces of mordant are wiped off and so removed1 and by using heated sawdust1 or heating the drum while rotating1 the fur acquires a fullness and play of the hair which are great desiderata in furs4 ,the sawdust must then be shaken out of the furs4 ,this is done by cageing4 ,in some instances1 the drum itself can be converted into a cage1 by replacing the solid door with one made of a wire screen4 7,fig4 #af47 ,usually1 however1 the skins are removed from the drum and put in a separate cage1 which is built like the drum1 but has a wire net all around it1 through which the sawdust falls1 while the skins are held back4 ,the cages are generally enclosed in compartments in order to prevent the sawdust from flying about and forming a dust which would be injurious to the health of the workers4 ,in large establishments1 the drum-cleaning machinery occupies a large section of the plant1 many drums and cages being used1 and special arrangements being made to take care of the sawdust which can be used over again several times1 until it becomes quite dirty4 ,illustration3 ,,fig4 #ae4 ,,drum4 7,,combination ,,drum ,,and ,,cage ,,as ,a ,,drum47 7,f4 ,blattner1 ,brooklyn1 ,new ,york47 ,illustration3 ,,fig4 #af4 ,,cage4 7,,combination ,,drum ,,and ,,cage ,,as ,a ,,cage47 7,f4 ,blattner1 ,brooklyn1 ,new ,york47 ,with this operation ends the ordinary procedure of fur dressing4 ,but there are several additional processes required in the treatment of certain furs1 which are generally undertaken by the dresser1 and chief among these are shearing and unhairing4 ,sometimes this work is done in separate establishments organized solely for this business4 ,certain kinds of furs1 among them being seal1 beaver and nutria1 possess top-hair which may detract from the beauty of the fur1 the true attractiveness being in the fur-hair4 ,the top-hairs are therefore removed1 and for this purpose machines are now being used4 ,formerly this work was all done by hand1 and on the more expensive furs like seal and beaver1 unhairing is now done on a machine operated by hand4 ,the principle of the process is as follows3 ,the skins are placed on a platform and the hair blown apart by means of a bellows4 ,the stiff top-hairs remain standing up1 and sharp knives are brought down mechanically to the desired depth1 and the hair is cut off at that point4 ,the skin is then moved forward a short distance1 and the process repeated until all the top-hairs have thus been cut out4 ,with muskrats1 or other pelts which do not require such very careful attention1 the whole process is done automatically on a machine4 ,the fur-hair is brushed apart by means of brushes and a comb1 and at regular intervals1 sharp knives cut off the top-hairs4 ,several hundred skins can be unhaired in a day on such a machine requiring the attention of only one man4 ,a machine for unhairing skins is shown in ,fig4 #ag4 ,illustration3 ,,fig4 #ag4 ,,unhairing ,,machine4 7,seneca ,machine ,tool ,co41 ,inc41 ,brooklyn1 ,n4 ,y47 ,with other furs1 such as rabbits1 hares1 etc41 where the trouble of unhairing would be too great commensurate with its advantages1 the hair is sheared instead4 ,the top hair is cut down to the same length as the under-hair by means of shearing machines which can be regulated to cut to any desired length of hair4 ,a typical device for shearing furs is shown in ,fig4 #ah4 ,illustration3 ,,fig4 #ah4 ,,fur-,,shearing ,,machine4 7,seneca ,machine ,tool ,co41 ,inc41 ,brooklyn1 ,n4 ,y47 ,,chapter ,,vii ,,water ,,in ,,fur ,,dressing ,,and ,,dyeing ,the assertion has often been made1 although its absurdity is now quite generally realized1 that the success of the ,european fur dressers and dyers1 particularly in ,leipzig1 is due to the peculiar nature of the water used1 which is supposed to be especially suited for their needs4 ,the achievements in this country in the fur dressing and dyeing industry during the past few years are ample and sufficient answers to the claim of foreign superiority in this field no matter what reason may be given1 and particularly when the quality of the water used is advanced as a leading argument4 ,for the water employed by the establishments in and about ,new ,york1 as well as in other sections of the country is surely not the same as the water of ,leipzig1 yet the work done here is in every respect the equal of1 if not better than the foreign products4 ,it is interesting to note that similar rumors were current here in the early period of the development of the ,american coal-tar industry since #aiad4 ,our efforts to establish an independent dyestuff industry were doomed to failure1 according to those who circulated the stories1 because we did not have the water1 which they claimed was responsible for the ,german success4 ,the present status of the ,american dye business1 in its capacity satisfactorily to supply most of the needs of this country and of others as well1 speaks for itself4 ,however1 as is often the case with such erroneous assertions1 there is just enough of an element of truth in the statement regarding the peculiar qualities of certain kinds of water1 to make the matter worthy of consideration4 ,water is certainly a factor of great importance in fur dressing and dyeing1 and it is not every sort of water that is suitable for use4 ,this fact was recognized by the early masters of the art1 for they invariably used rain-water as the medium for their tanning and dyeing materials1 and their choice must be regarded as an exceedingly wise one4 ,while the necessity for giving consideration to the quality of the water for fur dressing purposes is great1 it is in fur dyeing that the effects of using the wrong water are largely evident1 and so extra care must be exercised in the selection of water for this purpose4 ,the essential requirements for a water suitable for the needs of the fur dressing and dyeing industry1 are3 first1 a sufficient1 constant and uniform supply2 and second1 the absence of certain deleterious ingredients4 ,chemically pure water is simply the product of the combination of two parts by volume of hydrogen with one part by volume of oxygen4 ,such water can only be made in the laboratory1 and is of no importance in industry4 ,for practical purposes1 distilled water may be regarded as the standard of pure water4 ,here1 too1 the cost and trouble involved in the production of distilled water on a large scale is warranted only in a certain few industrial operations4 ,a natural source of water which in its character most nearly approaches distilled water is rain4 ,in fact1 rain-water is a distilled water1 for the sun's heat vaporizes the water from the surface of the earth forming clouds1 which on cooling1 are condensed and come down as rain4 ,rain-water is usually regarded as the purest form of natural water4 ,exclusive of the first rain after a dry period1 rain-water is quite free of impurities1 except possibly for a small percentage of dissolved atmospheric gases1 which are practically harmless1 and which can usually be readily eliminated by heating the water4 ,moreover1 rain-water is quite uniform in its composition throughout the year in the same locality1 and it possesses all the desirable qualities of a water suited for fur dressing and dyeing purposes4 ,formerly when the quantity of water used in the industry was comparatively small1 the supply from rain was sufficient to meet all the requirements4 ,but now1 when tremendous quantities of water are used constantly1 rain-water is no longer a feasible source1 and other supplies must be utilized1 although in a sense1 all water may be traced to rain-water as its origin4 ,when rain-water falls on the earth it either sinks into the ground until it reaches an impervious layer1 where it collects as a subterranean pool1 forming a well1 or continues to flow underground until it finally emerges at the surface as a spring2 or on the other hand the rain-water may sink but a short distance below the surface1 draining off as ponds1 lakes or rivers4 ,in the first case the water is called ground water1 in the latter it is known as surface water4 ,ground water usually contains metallic salts in solution1 and relatively little suspended matter4 ,if the water has percolated through igneous rocks1 like granite1 it may be quite free even of dissolved salts1 and such water is considered 8soft40 ,if1 however1 the rocky formations over which1 or through which1 the water has passed contain limestone or sandstone1 or the like1 salts of calcium and magnesium will be dissolved by the water4 ,the presence of the lime and magnesia salts1 as well as salts of aluminum and iron1 in the water1 causes it to be what is termed 8hard40 ,surface water is more likely to contain suspended matter1 with very little of dissolved substances4 ,suspended matter1 like mud1 contains much objectionable matter such as putrefactive organisms and iron1 but most of these materials can be removed by filtration or sedimentation1 and seldom cause any difficulties4 ,hardness in water is generally the chief source of trouble when the water is at fault4 ,hardness may be of two kinds1 either permanent1 or temporary1 or sometimes both are found together4 ,water which is permanently hard usually contains the lime and magnesia combined as sulphates4 ,temporary hardness1 on the other hand1 is due to the presence of lime and magnesia in the form of bicarbonates1 the carbon dioxide contained in the water having dissolved the practically insoluble carbonates3 ,ca,c,o ,,co ,h,o ,ca7,,hco7 calcium carbon water calcium carbonate dioxide bicarbonate ,temporary hardness can be eliminated by heating the water1 the carbon dioxide being expelled and the carbonates of lime and magnesia being precipitated and then filtered off4 ,both permanently and temporarily hard waters can be softened by the addition of the proper chemical1 such as an alkaline carbonate like sodium carbonate4 ,this precipitates insoluble carbonates of the lime1 magnesia1 iron and aluminum1 leaving a harmless salt of sodium in solution in the water4 ,the sludge is allowed to settle in tanks before the water is used4 ,in fur dressing and dyeing1 water is employed for soaking and washing the skins1 dissolving chemicals1 extracts and dye materials1 and also for steam boilers4 ,a small amount of hardness in the water is not harmful1 and up to #aj parts of solid matter per #ajj1jjj1 may be disregarded4 ,permanent hardness is particularly objectionable in water for boiler purposes1 as it forms scale4 ,the effect of the impurities of the water depends on the nature of the chemicals and dyes used4 ,where acids are used in solution compounds of magnesium1 lime and aluminum will generally not interfere4 ,hard water must not be used for soap solutions1 as sticky insoluble precipitates are formed with the soap by the metals1 this compound adhering to the hair1 and being difficult to remove1 will cause considerable trouble in subsequent dyeing4 ,an appreciable loss of soap also results1 as one part of lime1 calculated as carbonate will render useless twelve parts of soap4 ,in tanning or mordanting1 where salts of tin1 aluminum or iron are employed1 hard water should not be used1 as lime and magnesia will form precipitates with them4 ,bichromates will be reduced to neutral salts1 and cream of tartar will also be neutralized4 ,with dyes also1 hard water has a deleterious effect4 ,basic dyes are precipitated by this kind of water1 rendering part of the dye useless1 and also causing uneven and streaky dyeings4 ,sometimes the shades of the dyeings are modified or unfavorably affected4 ,considerable quantities of lime and magnesia in the water will cause duller shades with logwood and fustic dyeings4 ,the presence of iron1 even in very slight quantities generally alters the shade1 darkening and dulling the color4 ,these facts were apparently all recognized and understood by the fur dressers and dyers of an earlier period1 for instead of utilizing the water of lakes and streams near at hand1 which afforded a more constant supply1 but which contained harmful impurities1 they collected the rain-water1 which was always soft4 ,whether they realized the nature and character of the substances that make water hard is uncertain1 but they were always careful to avoid such water4 ,at the present time establishments located in and about large cities like ,new ,york1 where the majority of ,american fur dressing and dyeing plants are situated1 have no trouble about the water4 ,the cities supply water which is soft1 suitable alike for drinking and industrial purposes4 ,other plants1 not so fortunately situated1 often have to employ chemical means to treat the water so as to make it suitable for use4 ,,chapter ,,viii ,,fur ,,dyeing ,,introductory ,,and ,,historical ,in discussing fur dyeing1 the question naturally arises1 8,why dye furs at all8 ,are not furs most attractive in their natural colors1 and therefore more desirable than those which acquire their color through the artifices of man80 ,the answer cannot be given simply4 ,natural furs of the more valuable kinds are indeed above comparison with the majority of dyed furs4 ,yet there are several reasons which fully justify and explain the need for fur dyeing1 for at the present time1 this branch of the fur industry is almost as important and indispensable as the dressing of furs4 ,the first application of dyeing to furs1 had for its purpose the improvement of skins which were poor or faulty in color2 or rather1 the object was to hide such defects4 ,as nearly as can be ascertained1 this practise was instituted at some time during or before the fourteenth century1 for fur dyeing seems to have been common during that period1 as is apparent from the verses of a well-known ,german satirist1 ,sebastian ,brant1 who lived in the latter part of the fourteenth century3 8,man kann jetzt alles ,pelzwerk frben1 ,und tut es auf das schlechste gerben40 ,however1 at a later period1 there was a general condemnation of the dyeing of furs1 and among the list of members of the furrier's guilds1 none can be found who are described as dyers4 ,there is a record of a decree issued by a prince in a ,german city in the sixteenth century1 prohibiting the practise of fur dyeing4 ,inasmuch as furs were worn only by the nobility and certain other privileged classes1 and also were very costly1 there was great profit to be had by dyeing inferior skins so as to disguise the poor color1 and then selling such furs at the price of superior quality skins4 ,this was undoubtedly the reason for the prohibitory decree1 but there were some who continued to practise the forbidden art in secret1 using secluded and out-of-the-way places for their workshops1 and mixing their carefully-guarded recipes with as much mystery as the witches did their magic potions4 ,these circumstances probably account for the great amount of mystery which has been1 and still is to a considerable degree1 attached to fur dyeing1 and also explains the opprobrium and distrust with which fur dyers were formerly regarded4 ,even at the present time1 dyeing is often employed to improve furs which are faulty in color4 ,it frequently happens1 that in a lot of skins there are some which are considerably off shade1 or in which the color is such as to appreciably reduce their value below the average1 the hair being usually too light a shade1 or of uneven coloring4 ,by carefully dyeing these skins of inferior color1 they can be made to match very closely the best colored skins of the particular lot of furs1 and consequently increase their value4 ,with most of the cheaper kinds of furs1 the trouble and cost of improvement by dyeing would not be worth while today2 but with some of the more valuable furs1 and especially such as are very highly prized1 like the ,russian sable1 or marten1 or chinchilla1 the darkening of light skins by the skillful application of fast dyes to the extreme tips of the hair1 will increase their value sufficiently to warrant the expense4 ,this dyeing or 8blending0 as it is called in such cases1 is done in such a clever and artistic manner that only experts can distinguish them from the natural4 ,dyeing used for such purposes is not objectionable1 provided the skins are sold as dyed or 8blended40 ,there are certain kinds of furs1 such as the various lambs1 ,persian1 ,astrachan1 ,caracul1 etc41 which are never used in their natural color1 because it is usually of a rusty brownish-black4 ,these are furs possessing valuable qualities otherwise1 so they are dyed a pretty shade of black1 which brings out the beauty of the fur to the fullest extent4 ,sealskins are also dyed always4 ,formerly they were dyed a deep1 rich dark brown1 resembling the finest shades of the natural color1 but now the seals are dyed black with a brownish undertone1 a color quite different from the natural4 ,while these two instances cannot be said to be cases of dyeing to disguise faulty color1 they are examples of improvement of color by dyeing4 ,closely associated with the use of dyes to increase the value of a fur by improving its color1 is the dyeing of skins of a certain lot of furs to produce a uniform shade1 thereby facilitating or to a considerable degree eliminating the task of matching the skins by the furrier4 ,this is usually done only on skins which are quite small1 of which a great many are needed in the manufacture of fur garments1 because the matching of several hundred skins would entail too much time and labor commensurate with the value of the fur4 ,the most notable instance of the use of dyes to produce a uniform shade on furs is the case of the moleskin4 ,occasionally1 furs are dyed after being made into garments1 by careful application of dyes1 in order to obtain certain harmonious effects1 such as uniformity of stripe1 or to produce a desired gradation of shade among the different skins comprising the garment4 ,not infrequently1 the great variety of shades and color schemes which ,nature provides in the different furs1 becomes insufficient to satisfy the desire of the fur-wearing public for something new4 ,the whims of fashion always require some novel effect1 even though it be for only one season4 ,to meet this demand for novelty1 fantasy or mode shades are produced on suitable furs1--colors which do not imitate those of any animal at all1 but which1 nevertheless1 strike the popular fancy4 ,it often happens that such a color becomes quite popular1 and enjoys a considerable vogue1 to the great profit of those who introduced the particular color effect4 ,the best ones1 however1 meet with only a comparatively short-lived demand1 being soon superseded by different color novelties4 ,the basis1 though1 of the greatest proportion of fur dyeing at the present time1 is the imitation of the more valuable furs on cheaper or inferior skins4 ,with the gradual popularization of furs as wearing apparel since the beginning of the last century1 the demand for furs of all kinds has increased enormously4 ,the supply of furs1 on the other hand1 and especially of the rarer kinds1 has had difficulty in keeping pace with the requirements1 and as a result there is a shortage4 ,a very effective means of relieving this shortage1 to a great degree1 at any rate1 is the dyeing of imitations of the scarcer furs on cheaper skins4 ,there are many animals among the more common1 and more easily obtainable ones1 whose skins are admirably suited as the basis of imitations of the more costly furs4 ,some of the furs which are adapted for purposes of dyeing imitations are marmot1 red fox1 rabbit1 hare1 muskrat1 squirrel1 opossum1 raccoon1 and many others1 and the imitations made are those of mink1 sable1 marten1 skunk1 seal1 chinchilla1 etc41 and indeed1 there are very few valuable furs1 which have not been dyed in imitation on cheaper pelts4 ,on account of the general mystery which formerly surrounded fur dyeing establishments1 and which has persisted to this day1 although to a lesser degree1 many peculiar notions were held1 even by those in the fur trade1 concerning the production of imitations4 ,the idea that in order to 8make0 a certain fur out of a cheaper skin1 it was necessary to use the blood of the animal imitated1 is typical of the conceptions of fur dyeing held not so long ago4 ,to-day1 while the knowledge generally possessed about this branch of the fur industry is meagre and vague1 the air of mystery and secrecy has become somewhat clarified1 and such ideas as are current about fur dyeing are more rational than formerly4 ,the dyeing of imitations is quite an artistic kind of work1 and indeed fur dyeing ought to be classed among the finest of industrial arts4 ,some of the reproductions achieved by dyers on a commercial scale are truly admirable4 ,the possibility of imitating the finer furs on cheaper skins naturally led to abuse1 the dyed furs being passed off frequently on the unsuspecting and uninformed buyer as the genuine original4 ,in fact1 this practise became so flagrant that in ,england laws were enacted to remedy the evil4 ,at the present time1 dyed furs are all sold as such1 although there always may be some unscrupulous merchants who seek to profit by deception4 ,some of the imitations and the names of the furs for which they were sold1 are as follows3 ,muskrat1 dyed and plucked sold as seal ,nutria1 plucked and dyed sold as seal ,nutria1 plucked and natural sold as beaver ,rabbit1 sheared and dyed sold as seal or electric seal ,otter1 plucked and dyed sold as seal ,marmot1 dyed sold as mink or sable ,fitch1 dyed sold as sable ,rabbit1 dyed sold as sable ,rabbit1 dyed and sheared sold as beaver ,muskrat1 dyed sold as mink or sable ,hare1 dyed sold as sable1 fox1 or lynx ,wallaby1 dyed sold as skunk ,white rabbit1 natural sold as ermine ,white rabbit1 dyed sold as chinchilla ,white hare1 dyed or natural sold as foxes1 etc4 ,goat1 dyed sold as bear1 leopard1 etc4 ,this list serves to indicate but a few of the great number of possibilities which are available for the fur dyer to produce imitations of the better classes of furs4 ,needless to say1 these imitations cannot1 as a general rule1 equal the originals1 because while the color is one of the most important features in judging the fur1 the nature of the hair1 gloss1 waviness1 thickness1 and also the durability are essential considerations1 and it is only in certain instances that skins used for imitations approach the originals in these respects4 ,however1 for the purposes and desires of the majority of people who wear furs1 the imitations are deemed quite satisfactory1 and they also have the advantage of being cheaper than the natural originals4 ,for whichever reason furs are dyed1 there is no doubt that the art of fur dyeing is one of the most difficult kinds of application of dye materials4 ,in the dyeing of the various textiles1 either as skein or woven fabric1 the material is of a uniform nature1 and therefore the dye is absorbed evenly by the fibres4 ,moreover1 textiles are dyed at1 or near the boil1 the dyestuff being more uniformly and permanently taken up from solution by the fibre at elevated temperatures4 ,how different is the case with furs6 ,far from being homogeneous1 furs present the greatest possible diversity of fibres to be dyed4 ,as already noted elsewhere1 fur consists of two principal parts1 the hair and the leather1 differing widely in their actions toward dyes4 ,as a general rule1 the leather absorbs dyestuffs much more readily than the pelage1 and inasmuch as fur dyeing is intended mainly and primarily to apply to the hair1 there is usually an appreciable loss of dye material due to its being absorbed by the leather1 and thereby rendered unavailable for dyeing the hair4 ,this fact must be taken into account in the dyeing of furs1 and the methods must be adapted accordingly4 ,with reference to the hair itself1 not only has each class of furs hair of a different kind1 but even in the same group there is always a considerable divergence in the properties of the hair4 ,the fur-hair1 being more or less of a woolly nature1 takes up the dye with comparative ease1 while the top-hair is quite resistant to the action of all dye materials4 ,as pointed out in the discussion of the nature of fur1 on different parts of the same pelt the hair varies in its capacity for absorbing coloring matters4 ,the color of the hair1 also frequently presents a great variety throughout the skin1 both in fur-hair and top-hair4 ,yet with all this lack of uniformity and homogeneity1 the dyed fur must be of an even color1 closely approaching the natural1 gently graded and without any harsh or unduly contrasted effects4 ,the natural gloss of the hair1 one of the most valuable qualities of the fur1 must be preserved4 ,this is by no means a simple matter1 for the luster is affected by dyes and chemicals with comparative ease1 and especially careful treatment is necessary to prevent any diminution of the gloss4 ,when the leather part of the fur is exposed to solutions of a temperature exceeding #dj-ej centigrade1 it soon shrivels up or shrinks1 and on drying the pelt1 becomes hard and brittle1 and therefore quite useless4 ,methods of fur dyeing have to take into consideration this fact1 and the temperature of the dyebath must not be greater than #ce-dj centigrade4 ,to be sure1 certain dressings make furs capable of withstanding much higher temperatures1 but their applicability is not universal1 being suited only for a very limited special class of dyestuffs4 7,v4 ,fur ,dressing74 ,the necessity for employing comparatively low temperatures1 coupled with the great resistance of the hair to the absorption of dye1 even at much higher temperatures1 makes fur-dyeing a very difficult operation indeed4 ,another obstacle which must be surmounted1 is the possibility of extraction by the dye solution1 of those materials1 chemical or otherwise1 which are contained in the leather1 and which are the basis of its permanence1 softness and flexibility4 ,for in the majority of dressing processes1 the action of the ingredients is a preservative one1 and when these are wholly or partially removed from the leather during the dyeing1 it becomes1 on drying1 hard and horny1 like the original undressed pelt4 ,in cases where furs are to be dyed1 special dye-resisting dressings must be used1 or the dyed skins must receive an additional dressing before drying4 ,dyeings on furs1 to have any value1 must possess great fastness to light1 rubbing and wear1 and must not change color in time1 either when the furs are stored1 or when made up into garments4 ,the necessity for fur dyeings to have these properties1 together with the difficulties outlined above1 has greatly limited the field of available dyeing materials1 as well as the methods of application4 ,these will now be taken up in detail4 ,,chapter ,,ix ,,fur ,,dyeing ,,general ,,methods ,before the furs can be dyed1 they have to undergo certain preparatory processes3 first1 killing1 which renders the hair more susceptible to the absorption of the dye2 and second1 mordanting1 which consists in treating the killed fur with chemicals which help the dye to be fixed on the hair4 ,then the skins are ready to be dyed4 ,there are two principal methods by which dyes are applied to furs in practise3 the brush process1 whereby only the tips or the upper part of the hair are colored2 and the dip process1 whereby the entire fur1 including the leather is dyed4 ,all other procedures in fur dyeing are modifications or combinations of these two4 ,killing solutions and mordanting solutions are also applied by one of these methods1 usually the dip process1 although very frequently combinations of the brush and dip methods are used4 ,chronologically the brush method of dyeing came first4 ,the early masters of the art were extremely fearful about employing any means by which there was a possibility of the leather being in any way affected4 ,they naturally had to devise such methods as would give the desired effect in a satisfactory manner1 and as would be confined solely to the hair part of the fur1 leaving the leather untouched4 ,by applying the dye or other material to be used1 in the form of a paste with a brush1 the upper portion of the hair only was treated4 ,for different kinds of furs different sorts of brushes were used1 and the depth to which the hair was colored could be controlled by skillful manipulation of the brushes4 ,it was frequently necessary to give a ground color to the hair1 the lower part being dyed a different shade from the tips4 ,this was accomplished by spreading the dye paste over the hair with a broad brush1 and then beating the color in with a specially adapted beating brush4 ,with larger furs1 two skins were placed hair to hair after the dye had been brushed on1 and the color forced to the bottom of the hair by a workman tramping on the skins4 ,the dyeing of seal was a typical illustration of these procedures4 ,first the tips of the hair were dyed4 ,the color was brushed on1 allowed to dry1 then the excess beaten out with rods4 ,these operations were repeated until the proper depth of shade was obtained1 often as many as a dozen or more applications of the dye being necessary4 ,then the base color was spread over the hair1 and beaten or tramped in until the lower parts of the hair were penetrated4 ,this process also required drying and beating out of the excess dye1 as well as numerous applications of the dye to impart the desired color to the hair4 ,prior to the dyeing1 the furs were killed1 by brushing on a paste containing the essential ingredients1 drying and beating and brushing the fur1 just the same as in dyeing4 ,it will be readily seen that such methods were exceedingly laborious1 and in some cases the dyeing took many weeks1 and even months4 ,it was quite a step forward when a certain fur dyer1 possessing a little more courage1 or perhaps1 experimenting spirit than the others1 attempted to dye furs by dipping them entirely into a bath containing a solution of the dye instead of applying a paste as formerly4 ,the advantages to be gained by such a method of dyeing were many4 ,a large number of skins could be treated thus at one time1 and this was a very important consideration in view of the great increase in the demand for dyed furs4 ,by allowing the furs to remain in the dye solution until the proper shade was obtained1 the time and labor of applying many coats of dye by brush was considerably reduced1 and in addition1 there was a greater probability of the products coming out all alike1 uniformly dyed4 ,the results as far as the hair was concerned1 were indeed highly gratifying1 but the condition of the leather after dyeing was not so encouraging4 ,this difficulty has to a considerable degree been overcome1 although there are frequent instances of the leather being affected by the dyeing process even with modern methods4 ,however1 the remedy in such cases1 or rather the preventative is the proper dressing of the skins prior to the dyeing4 ,the dip method of dyeing has acquired great importance1 and is being employed in dyeing operations involving the handling of millions of skins annually4 ,in certain instances1 nevertheless1 the brush method is of prime significance as in the dyeing of seal1 and seal imitations on muskrat and coney1 enormous quantities of furs being dyed in this fashion4 ,in the majority of imitations dyed1 both the brush and the dip methods must be used4 ,figure #ai illustrates the various types of brushes which are used at the present time for the application of the dye by the brush method4 ,each brush has a specific purpose and use4 ,the procedure in brush dyeing is somewhat as follows4 ,the skins1 after being properly treated1 that is1 killed1 and mordanted1 are placed on a table1 or work-bench1 hair-side up4 ,then by means of a brush which is adapted to the nature and requirements of the particular fur1 the solution is brushed on in the direction of the fall of the hair1 occasionally beating gently with the brush so as to cause the dye to penetrate to the desired depth4 ,considerable skill and care must be exercised in this operation as it is rather easy to force the dye down further than is wanted1 and in some cases the leather or the roots of the hair may be affected4 ,the skin having received its coat of dye1 is then dried and finished1 if no other dyeing processes are to be applied4 ,frequently1 with certain types of dyes1 several applications of color are necessary1 and these are brushed on as the first one1 drying each time4 ,then1 on the other hand1 the skin may receive a dyeing in the bath by dipping1 and for this also1 the fur is first dried after the brush dyeing4 ,illustration3 ,,fig4 #ai4 ,,brushes ,,used ,,in ,,fur ,,dyeing ,,by ,,the ,,brush ,,method4 ,quite recently1 owing to the great quantities of furs which are being dyed as seal imitations1 chiefly by the brush method1 although the dip method is used in conjunction with it1 machines have been invented to replace the hand brush1 and the dye is now applied mechanically4 ,machines for this purpose are by no means new1 there being records of inventions almost a score of years past1 but they did not achieve much success4 ,brush-dyeing machines1 to be efficient1 must be designed to suit the needs of the particular type of fur to be dyed1 otherwise there will be a great lack of uniformity in the dyed skins1 a condition which cannot occur when the dye is brushed on by hand brushes4 ,figure #bj;,a and ,b shows diagrammatically1 machines invented within the past few years1 which are used to dye mechanically furs by the brush process4 ,illustration3 ,,fig4 #bj4 ,,types ,,of ,,machines ,,for ,,dyeing ,,furs ,,by ,,the ,,brush ,,method4 ,a4 7,u4 ,s4 ,patent #a1bbe1ddg47 ,b4 7,u4 ,s4 ,patent #a1cdc1cee47 ,illustration3 ,,fig4 #ba4 ,,drum ,,for ,,working ,,with ,,liquids4 7,turner ,tanning ,machinery ,co41 ,peabody1 ,mass47 ,for the dipping process1 the dye solution is prepared in vats1 or liquid-tight drums1 or in some instances in paddle arrangements4 ,the skins are placed in the dye-bath1 and the dyeing operation proceeds without any difficulty4 ,after the proper shade is obtained1 the furs are removed1 washed free of excess dye1 dried and finished4 ,the dipping method is employed where a single shade is to be dyed on the fur1 as the production of blacks on lambs4 ,but in most cases1 the dyeing in the bath is supplemented by the application of a coat of dye by the brush to the upper part of the hair1 the color being usually a darker shade than the ground dyeing4 ,thus1 for example1 in the dyeing of imitation sable on kolinsky or a similar fur1 the skins are first dyed the relatively light color of the under-hair by the dip process1 then the dark stripe effect is brushed on4 ,the blending of sables1 martens1 chinchillas or other rare furs1 is not done in the same manner as with other furs1 because each skin requires individual attention and a long and careful treatment4 ,the dye solution is applied by means of very fine brushes or sometimes feathers1 to the extreme tips of the hair1 until the proper degree of color intensity is obtained4 ,the time1 labor1 and skill necessary for this sort of work are warranted only in the case of the highest-priced furs1 and the blendings are so excellent as to defy detection1 except by experts4 ,illustration3 ,,fig4 #bb4 ,,device ,,for ,,conveying ,,skins4 7,turner ,tanning ,machinery ,co41 ,peabody1 ,mass47 ,after the furs have gone through all the operations required by the processes of killing1 mordanting1 dyeing and washing1 they are ready to be dried and finished4 ,the procedure is quite similar to that employed in fur dressing4 ,sometimes the leather side of the skins is brushed with a strong salt solution before drying1 in order to replace some of the salt which was extracted during the dyeing processes4 ,in other instances1 a light coat of some oily substance is brushed on1 to render the leather soft and flexible after drying1 where there is a possibility of the skins turning out otherwise4 ,great care must be exercised in the handling of the dyed skins to avoid the formation of stains or spots on the hair1 which might ruin the dyeing4 ,as little handling of the furs as is feasible will reduce any trouble from this source4 ,in conveying the wet skins from one part of the plant to another it is desirable to use a device such as is shown in ,fig4 #bb4 ,for drying1 the same machines as described under ,fur ,dressing can be used1 and similar care must be taken to avoid overheating or irregularity of drying4 ,drum-cleaning constitutes a very important operation in the finishing of the skins1 the hair receiving a polish1 and the full lustre and brilliancy of the dye being thereby brought out4 ,then after caging to remove the sawdust or sand1 the skins are passed over the staking knife1 or are treated in a machine suited for the purpose1 to stretch them and to render them thoroughly soft and flexible4 ,and therewith is concluded the work of the fur dyer proper1 and the skins are ready to return to the furrier1 in whose hands they undergo the metamorphosis into the fur garments to be worn chiefly by the feminine portion of humanity4 ,,chapter ,x ,,fur ,,dyeing 8,,killing0 ,,the ,,furs ,if dressed furs are treated with a paste or solution of a dye properly prepared1 and at the right temperature1 the hair will show very little tendency to absorb the coloring matter4 ,even after prolonged treatment with the dye1 only a small amount will be taken up by the hair1 and in a very irregular fashion4 ,soft1 woolly hair1 like that of lambs and goats will be colored more easily than that of furs with harder hair1 and the under-hair of a fur will generally have a greater affinity for the dye than the harder and stiffer top-hair4 ,moreover1 in some parts of the same fur1 the hair will absorb more color than in other parts4 ,in other words1 the hair of furs resists the action of dye materials to a greater or less degree1 depending upon the character of the fur1 and also upon the part of the pelt4 ,in order to overcome this resistance of the hair1 and to render it uniformly receptive to the coloring substances1 the furs are treated with certain chemical agents1 the process being known technically as 8killing40 ,the origin of the term is obscure1 but it is interesting to note that in the fur dyeing countries other than the ,united ,states and ,england1 the corresponding expression is used3 in ,germany1 8tten10 and in ,france 8tuer40 ,the explanation of the process is as follows3 ,the surface of the hair is covered with a fine coat of fatty material which renders the hair more or less impervious to dye solutions and solutions of other substances which may be used for dyeing purposes4 ,this fatty coating of the hair cannot be removed by mechanical means1 otherwise the hair would have been freed of it during the dressing operations4 ,chemical solvents must therefore be resorted to1 and naturally alkaline materials are used1 these being usually cheapest and also most effective in their dissolving action on fatty substances4 ,alcohol1 ether1 benzine1 and other similar liquids also serve as killing agents on furs1 since they too1 are fat solvents4 ,in all these cases1 the fatty substance on the hair is dissolved away1 and the protective coat which previously rendered the hair impervious to the dye1 is now removed4 ,there are certain chemicals however1 which normally do not dissolve substances of a fatty nature1 but are strongly oxidizing1 such as peroxide of hydrogen1 hypochlorites1 permanganates1 perborates1 nitric acid1 etc41 and exert a killing action when they are applied to the hair1 in that the hair is made capable of taking up the dye from its solutions4 ,in this case the killing can hardly be said to be due to a degreasing process4 ,the fact that killing can be brought about with other substances than alkalies or fat solvents1 has led to the belief on the part of some investigators in this field that killing is more than a degreasing operation1 although the removal of the fatty material of the hair undoubtedly takes place4 ,some authorities consider that the killing process changes the pigment of the hair1 which thereby becomes more receptive to the dye4 ,it is quite possible that some such change in the structure of the hair fibre does take place1 the surface of the hair becoming slightly roughened1 and therefore more capable of fixing the coloring matter4 ,the question is still an open one1 and since no conclusive researches have been made as yet1 it will be assumed that killing is simply a degreasing process1 inasmuch as the modern practise is based on this supposition1 and very satisfactory results are obtained4 ,an account of the historical development of the killing process brings out many interesting and enlightening facts1 so it will be given here briefly4 ,one of the first substances used for killing1 or degreasing the hair of furs1 was decomposing urine4 ,urine contains about #b of urea which gradually changes to salts of ammonia1 and in the presence of the air1 largely to ammonium carbonate4 ,this substance has a weak alkaline action1 but sufficiently effective to be used for killing the hair of certain types of furs4 ,woolly furs1 such as those derived from the various kinds of sheep and goats1 were degreased with stale urine1 the skins being washed in this1 and then rinsed in water4 ,the fat was emulsified by the ammonium carbonate present1 and could thus be easily removed4 ,for other furs1 a stronger mixture was necessary4 ,an example of a killing formula used on wolf1 skunk and raccoon1 which were to be dyed black1 is the following3 #cej grams beechwood ashes #bjj grams unslaked lime #aej grams copper vitriol #ajj grams litharge #fj grams salammoniac #dj grams crystallized verdigris #c4e liters rain water ,beechwood ashes were a very important constituent of the old killing formulas4 ,the reason for that lies in the fact that beechwood contains a comparatively high percentage of potassium1 which occurs in the ashes of the burned wood as potassium carbonate1 or potash4 ,the ashes alone were frequently used1 being applied in the form of a paste1 which in some instances had an advantage over a solution1 in that the killing could be limited to certain parts of the skin where it was more desired than in other parts4 ,by extracting the wood ashes with hot water1 and evaporating the clear solution to dryness1 potash could be obtained1 which was considerably stronger than the original ashes4 ,next in importance for the killing was unslaked lime4 ,this substance was also often used by itself1 being first slaked with water1 and using the milk of lime thus formed1 after cooling4 ,salammoniac1 although a salt1 and consequently without any killing action1 in contact with the beechwood ashes or the lime in solution or paste1 liberated ammonia slowly1 and so also acted as a degreasing agent4 ,the other chemicals in the formula took no part in the actual killing of the hair1 but acted either as mordant materials or as mineral dyes4 ,the copper salts1 in this mixture present in two forms1 as sulphate in copper vitriol1 and as acetate in the verdigris1 were important constituents of the dye formula1 being essential to the production of the proper shade4 ,these substances properly had no place in the killing formula4 ,the litharge1 also was not a killing agent1 but in the presence of the alkaline materials of the killing mixture1 it gradually combined with the sulphur contained in the hair1 forming lead sulphide1 and thereby darkening the color of the hair4 ,in this case1 the metallic compound acted1 not as a mordant1 but as a mineral dye4 ,the mixture was applied to the hair by means of a brush1 the skins let lie for some time1 then dried1 brushed and beaten4 ,many applications were usually necessary to sufficiently degrease the hair4 ,inasmuch as the killing paste was prepared by mixing the constituents together1 and then was brushed on at the comparatively low temperatures which the proper protection of the hair required1 it is questionable whether some of the metal compounds were even enabled to act as described above as mordant or dye4 ,in spite of the trouble and considerable time required in working with such a killing formula to obtain the hair in the desired condition for dyeing1 the use of such a mixture nevertheless possessed the advantage that the hair was only very slowly and gradually acted upon1 and so the gloss was preserved4 ,the action of strong alkaline substances acting quickly is more or less detrimental to keeping the gloss of the hair1 while the slow action of the weak alkaline paste of the old formulas1 and the gradual formation of a protective metal film on the surface of the hair1 rendered the hair suitably receptive to the dye which was subsequently applied1 without in any measure affecting the lustre of the hair4 ,it would be needless to describe or discuss any more of the old killing formulas1 for the principle involved was the same in all cases1 there being usually a slight variation in the content of metallic salts1 beechwood ashes and unslaked lime being constituents of the great majority of the mixtures used4 ,modern killing processes employ substances quite similar to those of the old formulas1 the operations1 however1 being much less laborious and less time-consuming1 and the cheap1 pure products which chemical science has been able to develop being used in place of the crude products crudely obtained from natural sources4 ,the chemicals used at the present time for killing furs1 are chiefly ammonia1 soda ash1 caustic soda1 and caustic lime4 ,the choice of the killing agent depends upon the nature of the fur1 the hair of some furs being sufficiently killed by treatment with weak alkalies1 while in other furs the hair may require stronger treatment4 ,the ability of the hair of a particular fur to withstand the action of the different alkaline substances must be taken into consideration1 there being a great divergence in this regard among the different classes of furs4 ,raccoon1 for example1 is not appreciably affected by a solution of caustic soda of #e degrees ,beaum1 while some wolf hair cannot withstand the action of a solution of soda ash of less than #a degree ,beaum4 ,frequently much stronger alkalies are necessary to kill the top-hair than the under-hair1 so this accomplished by treating the skins in a solution which is suited to kill the under-hair1 and subsequently the top-hair is treated with a stronger solution1 this being applied by the brush method4 ,uniformity of action of the killing material on all parts of the skin1 and on all the skins of a given lot1 is absolutely essential to obtaining satisfactory results in dyeing4 ,and it is by no means a simple matter to get such uniformity1 considering the numerous factors that must be taken into account4 ,any operation involving the immersion of the skins in solutions or even in water alone1 has an effect on the leather side of the skin1 inasmuch as some of the tanning materials may be extracted4 ,the application of some substance of a fatty nature to a great degree prevents this1 and the skin can be killed1 mordanted and dyed1 and then come out soft and flexible4 ,but the great majority of substances of a fatty nature are affected by alkalies1 and so when the skins are being killed1 the action of the alkaline materials would be upon the fat contained in the leather as well as that upon the hair4 ,as a result the hair may not be sufficiently killed1 and so give uneven dyeings subsequently4 ,either a certain excess of the killing chemical must be used1 and it would be very difficult to ascertain what quantity would suffice1 or the killing action must be prolonged2 but best of all1 in oiling the skins1 an inert mineral oil should be used1 since it is wholly unaffected by alkalies4 ,skins may be killed by the brush process or the dip process1 or by both4 ,for brush killing1 the stronger alkalies like lime and caustic soda are used1 the solution being applied to the top-hair with a suitable brush1 and the skins allowed to remain hair to hair for the necessary length of time1 after which they are treated further as skins killed by the dip process4 ,by this latter process1 the furs are immersed in a solution of the desired killing agent in a vat1 or drum1 or other appropriate device which will permit of uniform action of the alkali on the hair of all the skins4 ,after remaining in the solution the required length of time1 the skins are drained1 and rinsed in fresh water1 and then entered into a weak solution of an acid in order to neutralize any remaining alkali1 it being easier to wash out acid than alkali4 ,the furs are then washed thoroughly in clear water1 preferably running water1 to remove the last traces of acid4 ,the skins are then drained and hydro-extracted1 or pressed1 and are then ready for the subsequent operations of mordanting and dyeing4 ,,killing ,,with ,,soda ,soda is sodium carbonate1 which is produced commercially in a very pure state in several different forms1 the chief being sal soda1 which is crystallized sodium carbonate1 containing about #cg of actual soda2 and soda ash1 or calcined soda1 which is anhydrous sodium carbonate4 ,the latter is the variety most commonly used4 #aj grams soda ash are dissolved in #a liter of water at #be-cj ,c4 ,the skins are immersed for #b-c hours1 after which they are rinsed and treated with #aj grams acetic acid dissolved in #a liter of water4 ,the skins are again thoroughly washed1 and then hydro-extracted4 ,,killing ,,with ,,lime ,lime1 calcium oxide1 forms a white1 amorphous1 porous substance1 which readily takes up water1 giving calcium hydroxide1 or slaked lime4 ,only the best grades of lime should be used1 as it is very frequently contaminated with calcium carbonate and other inert materials4 #aj grams of lime are dissolved in #a liter of water4 ,the skins are entered1 and allowed to remain for a period of time which varies according to the nature of the fur4 ,during the killing1 the solution must be agitated1 in order to evenly distribute the milk of lime1 which has a tendency to settle out4 ,after rinsing1 the skins are 8soured10 by treating with weak acetic acid solution1 then thoroughly washed1 and drained4 ,,killing ,,with ,,caustic ,,soda ,caustic soda is used only on furs the hair of which is very hard and resistant to killing4 ,usually it is applied by the brush process1 but in some instances1 the dip method must be used4 ,in order to reduce as far as possible1 the action of the caustic soda on the leather1 the weakest permissible solutions are used1 increasing the time of treatment1 if necessary4 ,caustic soda is a white1 crystalline substance1 occurring in commerce in lumps1 but more conveniently in a solution of #dj degrees ,beaum1 containing #ce of caustic soda4 ,various quantities1 ranging from #d to #be grams of this solution per liter of water are taken1 according to the character of the fur1 and the skins treated for #b-c hours1 although weaker solutions may be used1 and increasing the duration of the killing4 ,by keeping the solution in motion1 by means of a stirrer or any other method of agitation1 the best results are obtained4 ,after the skins are sufficiently killed1 they are soured1 and washed as by the other killing methods4 ,where the nature of the hair of the fur is such that the top-hair and the under-hair require different killing treatments1 the skins are first killed by the dip process1 with an alkali suited to kill the under-hair1 then a brush killing with a stronger alkali is applied to the top-hair4 ,the subsequent treatments are the same as for usual dip-killing methods4 ,,chapter ,,xi ,,fur ,,dyeing ,,mordants ,the hair of furs has the peculiar quality of fixing the oxides or hydroxides of certain metals from dilute solutions of their salts4 ,advantage is taken of this property to mordant the furs1 that is1 to cause a certain amount of the metallic oxide or hydroxide to be permanently absorbed by the fibres4 ,the term mordant comes from the ,french word 8mordre10 meaning to bite1 it being formerly considered that the purpose of a mordant was to attack the surface of the hair in such a way as to permit the dye to be more easily absorbed4 ,in fact1 killing mixtures1 which were intended for this same object1 used to contain the various chemicals which have a mordanting action1 in addition to the alkaline constituents4 ,the mordants were not applied as such1 but always as killing materials4 ,it was later realized1 however1 that the mordant was instrumental in the production of the color itself4 ,mordanting may be considered as having a two-fold object3 first1 to help fix the dye on the fibre in a more permanent fashion1 thus rendering the dyeings faster2 and secondly1 to help obtain certain shades of color1 as the various mordants produce different shades with any given dye4 ,some classes of dyes can be applied to furs without the use of mordants1 but other types are taken up only in a very loose manner1 being easily washed out from the hair with water1 and it is only when such dyes are brought on to the hair in the form of a metallic compound1 producing what is known as a 8lake10 that really fast dyeings are obtained with them4 ,the substances which are used for mordanting the hair are certain metallic compounds1 but not all metallic salts which are used in dyeing are mordants4 ,sometimes such a compound is employed to develop the color of the dyeing by after-treatment1 as in the case of after-chroming1 the action of the metallic salt being directed only to the dye1 and is not fixed by the fibre as a mordant must be4 ,in order for a metallic compound to act as a true mordant1 it must be fixed by the hair1 and it must combine with the dye1 thus forming a sort of connecting link between the dye and the hair4 ,it is not absolutely essential that the mordant be applied first1 although this is the customary and commonest practise4 ,there are three ways by which the mordants can be fixed on the fur hair3 ,first1 by the absorption of the metallic oxide or hydroxide from a solution of the mordant prior to the dyeing2 second1 the mordant may be fixed on the fibre at the same time as the dye2 and third1 the mordant may be applied after the fur has been treated with the dye4 ,the last two methods will be discussed in connection with the dyes1 as they are special cases4 ,the salts of metals which are comparatively easily dissociated in water1 with the formation of insoluble oxides or hydroxides1 are most applicable as mordants for furs1 and among them are compounds of aluminum1 iron1 chromium1 copper and tin4 ,the constituents of the hair seem to bring about the dissociation of the metallic salt1 and the oxide or hydroxide as the case may be1 is absorbed and firmly fixed by the hair4 ,just what the manner and nature of this fixation are1 is still uncertain4 ,it is supposed that chemical combination takes place between the hair and the metal4 ,the course of this process may1 as far as is known1 be described as follows1 taking1 for example1 the case of chromium sulphate3 ,in dilute solution1 this compound gradually dissociates first into its basic salts1 and finally into the hydroxide1 the breaking up of the neutral salt being induced by the presence of the fur-hair4 ,cr7,,so7 #b;,h,o ,cr7,,so77,,oh7 ,h,,so chromium water first basic sulphuric sulphate chrome salt acid ,cr7,,so77,,oh7 #b;,h,o ,cr7,,so77,,oh7 ,h,,so second basic chrome salt ,cr7,,so77,,oh7 #b;,h,o ,cr7,,oh7 ,h,,so chromium hydroxide ,these reactions take place within the fibre1 after the hair has been impregnated with the solution of the neutral salt1 and when the compound has been rendered completely basic1 in other words has reached the form of the hydroxide1 it is supposed to combine with the acid groups contained in the hair substance1 forming thus some complex1 insoluble organic compound of the metal within the hair4 ,according to some authorities the mordant is supposed to be present in the hair simply as the hydroxide1 being tenaciously held by some physical means4 ,the facts seem to indicate1 however1 that the metal is actually combined in some chemical way with the hair4 ,for1 if the mordant were present as hydroxide1 then on white hair it would show the color of the hydroxide1 which it does not4 ,the same facts obtain with regard to other metals4 ,in order for the hair to be properly mordanted1 it is necessary that the metallic compound which is taken up by the hair be held in such a manner that the mordant cannot be removed by water or even dilute acids or alkalies4 ,salts which dissociate too readily produce mordants which are only superficially precipitated on the hair and subsequently come off4 ,usually some substance is added to the solution of the salt to cause slower and more even dissociation of the salt1 so that the hair substance can be quite saturated with the metallic compound before any insoluble precipitate is formed4 ,dilute sulphuric acid1 organic acids like acetic and lactic1 and cream of tartar are used to facilitate the uniform absorption of the mordant salt by the hair4 ,when the skins are mordanted before dyeing1 they are immersed for #f to #bd hours in a solution containing #a to #bj grams of the metallic salts per liter of water1 together with the corresponding quantity of the assistant chemical4 ,the skins should be so entered into the mordant solution that the hair is uniformly in contact with the solution1 and all the skins so that they are acted upon alike4 ,machinery such as is used for killing is suitable for mordanting also4 ,the duration of the mordanting1 and the concentration of the solutions are varied according to the depth of shade required1 and also according to the nature of the dye to be employed4 ,by suitably combining several mordants a considerable range of colors can be obtained with a single dye4 ,the various chemicals used as mordants are essentially the same no matter for which class of dyes they are used1 there being only slight differences in the concentrations of the solutions1 the manner of application of the mordants being practically the same4 ,it is interesting to note that with the exception of chromium compounds1 which are of comparatively recent adoption as mordants1 all the chemicals now used for mordants were employed by the earliest masters of the art of fur dyeing4 ,while some of the formulas used by those dyers display a lack of appreciation of the true action and function of the mordanting chemicals1 yet it is quite remarkable that they chose1 in spite of their limited knowledge of chemical processes and phenomena1 just those materials which do act as mordants if properly applied4 ,the most important metallic compounds for mordanting furs at the present time are salts of aluminum1 iron 7ferrous71 copper1 tin and chromium 7as well as chromates and bichromates74 ,the compounds of the metals with organic acids such as acetic acid are preferable1 being more easily dissociated1 and also leaving in solution an acid which is less injurious to the fur than a mineral acid4 ,however1 sulphates and other salts of the metals are also used extensively1 inasmuch as they are cheaper than the organic salts4 ,,aluminum ,,mordants ,chief among the aluminum mordants are the various kinds of alum1 which is a double sulphate of aluminum and an alkali such as sodium1 potassium or ammonium4 ,all these salts except that of sodium1 form large1 colorless1 octahedral crystals1 and are soluble in about #aj parts of cold water1 and #a_/d part of hot water4 ,sodium alum is even more easily soluble1 but on account of the difficulty of obtaining it in crystalline form1 it is little used4 ,the common commercial alum is the potassium aluminum sulphate4 ,recently1 aluminum sulphate has to a large extent replaced alum for mordanting purposes1 because it can be obtained very cheaply in pure form1 and it contains a greater amount of active aluminum compound than does alum4 ,only the iron-free salt1 however1 may be used for the needs of fur dyeing4 ,aluminum acetate also finds extensive application as a mordant in fur dyeing1 and while somewhat more expensive than the alum or aluminum sulphate1 it has the advantage over these compounds of being combined with an organic acid1 which is preferable when the action on the hair and leather is considered4 ,aluminum acetate can be obtained in the market in the form of a solution of #aj degrees ,beaum1 but can also be prepared very easily as follows3 #ffe grams pure aluminum sulphate1 or #idh grams potassium alum1 are dissolved in #a liter of hot water4 #aacg grams of lead acetate 7sugar of lead7 are also dissolved in #a liter of hot water4 ,the two solutions are mixed1 and thoroughly stirred4 ,a heavy white precipitate forms1 which is filtered off1 and discarded after the solution has cooled4 ,the aluminum acetate is contained in the filtrate1 and the solution is brought to a density of #aj degrees ,beaum by the addition of water1 if necessary1 and is preserved for use in this form4 ,,iron ,,mordants ,ferrous sulphate1 iron vitriol1 or copperas1 as it is commonly known1 forms pale green crystals1 which on exposure to air lose water1 and crumble down to a white powder4 ,it is very soluble in both cold and hot water1 but the solutions oxidize very rapidly1 turning yellowish1 and should therefore be used immediately4 ,care must be taken that a good quality of iron vitriol be used for the mordant1 otherwise very unsatisfactory results will be obtained4 ,ferrous acetate is prepared in a manner similar to the aluminum acetate1 and is occasionally employed instead of the ferrous sulphate4 ,inasmuch1 however1 as the solution of ferrous acetate is very easily oxidizable when exposed to the air1 a more stable form is used1 and this comes on the market as iron pyrolignite or iron liquor4 ,this can be prepared by dissolving iron in crude acetic or pyroligneous acid1 or by treating a solution of iron sulphate with calcium pyrolignite4 ,iron liquor is really a solution of ferrous acetate that contains certain organic impurities which prevent1 or rather1 considerably retard the oxidation of the iron salt1 but which in no way interfere with its mordanting properties4 ,the commercial product can be had in various concentrations1 but #aj degrees ,beaum is the most usual and most convenient4 ,,copper ,,mordants ,the most important copper salts used in fur dyeing processes are copper sulphate1 or blue vitriol1 occurring in large blue crystals1 very soluble in cold and in hot water2 and copper acetate1 which is formed by treating a solution of copper sulphate with a solution of the requisite quantity of lead acetate4 ,copper acetate can also be obtained in the form of blue-green crystals1 very soluble in water1 the solution becoming turbid on prolonged heating1 due to the formation of a greenish basic copper acetate4 ,this insoluble compound is known commonly as verdigris1 although it is not usually produced in the manner mentioned4 ,numerous fur dyeing formulas contain verdigris1 but inasmuch as the basic copper acetate is insoluble and thus incapable of reacting with any of the substances used in dyeing1 it is assumed that the soluble normal copper acetate was meant1 for this compound is also sometimes called verdigris4 ,in addition1 there must be mentioned here a compound which formerly found extensive use in fur dyeing4 ,this is a double salt of copper and iron1 analogous to alum1 ferrous copper sulphate1 known as blue salt4 ,it is very seldom used at the present time1 being more effectively replaced by other substances4 ,,chromium ,,mordants ,the typical chromium mordant is chrome alum1 which is a potassium or ammonium chromium sulphate1 constituted just like the aluminum alums1 and forming crystals like these4 ,more frequently used1 nevertheless1 than the chrome alum1 is chromium acetate1 which is prepared from it1 either by treating a solution of the chrome alum with a solution of lead acetate1 or in the following manner3 #ej grams of chrome alum are dissolved in #ejj cubic centimeters of boiling water4 ,to this is added #ae grams of #bj ammonia1 diluted with #ae grams of water4 ,the precipitate which forms is filtered off1 and preserved1 the filtrate being discarded4 ,after thoroughly washing the residue on the filter it is dissolved in dilute acetic acid1 heating if necessary1 to effect solution4 ,other chromium compounds of an entirely different type are also used in fur dyeing1 these being chromates and bichromates1 the latter finding greater application than the former4 ,sodium bichromate is the salt most usually employed4 ,this forms orange-red crystals which are very soluble in water1 and in addition to its use as a mordant it also serves as an oxidizing agent for developing or fixing certain dyes on furs4 ,,tin ,,mordants ,compounds of tin find only limited application in fur-dyeing1 the only one of importance being tin salts1 stannous chloride1 which occurs in the form of white1 hygroscopic crystals1 which must be preserved in closed vessels4 ,it is very soluble1 but in dilute solutions it readily forms a basic salt1 so stannous chloride is usually used in very concentrated solutions4 ,,alkaline ,,mordants ,after the furs have been treated with the solution of some alkali for the purpose of killing the hair1 they are always passed through a slightly acidulated bath to remove any alkali which may still be adhering4 ,this operation must always be gone through before the skins can be mordanted or dyed1 for if it were neglected1 very uneven and uncertain results would be obtained4 ,this process1 however1 entails the expenditure of no small amount of time1 labor and chemicals when large lots of skins are being handled4 ,in order to eliminate this extra step of 8souring0 between killing and mordanting or dyeing1 it has been proposed to use alkaline mordants which combine the killing and mordanting functions1 and accomplish these two processes at the same time4 ,the advantages of employing such mordants are easily apparent4 ,cumbersome manipulation and handling of the skins1 with the attendant consumption of much time and labor are reduced to a minimum1 and besides there is no needless waste of chemicals as is the case in the ordinary methods of killing the furs4 ,the principle of alkaline mordants is not a strictly new one4 ,if it be remembered that the old killing formulas used by the fur dyers of an earlier age1 contained metallic salts with mordanting properties in addition to the alkaline substances1 which alone were effective as killing agents1 it would seem that the suggested alkaline mordants were merely a revival in modified form of the old processes4 ,this is undoubtedly true in a large measure1 for the killing mixtures which the old masters used certainly embodied the fundamental principle of simultaneous killing and mordanting1 although it was not recognized at that time4 ,modern alkaline mordants have therefore been devised which can be employed for killing and mordanting furs at the same time4 ,they are prepared as follows3 ,,alkaline ,,aluminum ,,mordant #bej grams of potassium alum are dissolved in #a liter of boiling water4 ,to this solution is added #cjj grams of soda ash1 previously dissolved in #gej c4c4 of water1 and the resulting precipitate is filtered off1 washed and pressed1 and then dissolved in a solution of #fe grams of caustic soda in #a liter of water4 ,,alkaline ,,chromium ,,mordant #bej c4c4 of chrome acetate mordant of #bj degrees ,beaum #cbj c4c4 of caustic soda solution of #ch degrees ,beaum 7#cb4e7 #aj c4c4 of glycerine #cj degrees ,beaum 7#ie7 ,the solution of these substances is brought up to a volume of #a liter by the addition of #dbj c4c4 of water4 ,,alkaline ,,iron ,,mordant #ach grams ferrous sulphate are dissolved in #cfb c4c4 of warm water4 ,cool and add #be c4c4 of glycerine4 ,then slowly and carefully add #be4e c4c4 of concentrated ammonia1 taking care that no precipitate forms4 ,while these alkaline mordants seem to have much in their favor1 there are certain possible objectionable features which must be considered4 ,the solutions of the mordants are generally very alkaline1 and not every fur can withstand more than a limited quantity of alkaline substance for longer than a comparatively short time4 ,suitable mordanting usually requires a longer time than killing does1 so with the use of the alkaline mordant1 if the skins remain in the solution until sufficiently killed1 they may be insufficiently mordanted1 while if the furs are treated long enough to be properly mordanted1 the hair may have been over-killed4 ,however1 the idea of the alkaline mordant is a good one1 and it is only a matter of time and patient1 scientific experimentation when the difficulties of the method will be eliminated1 and a much-desired process will become a practical realization4 ,the general methods for applying the various mordants of all sorts follow closely the procedure adopted for the killing formulas1 and similar precautions must be observed1 in order to obtain consistently uniform results4 ,with the exercise of care1 there is little reason for the mordanting operations to go wrong4 ,after proper treatment of the skins in the mordants1 they are removed and drained off1 then rinsed lightly in running water to remove the excess of mordant liquor1 after which they can be directly entered into the dye bath4 ,if it is not feasible to dye the mordanted skins at once1 as is often the case1 the skins are kept moist1 and under no circumstances allowed to dry4 ,,chapter ,,xii ,,fur ,,dyeing ,,mineral ,,colors ,,used ,,on ,,furs ,before the introduction of the fur dyes now used1 certain inorganic chemical substances were employed in addition to the vegetable dyes1 for the production of colors on furs4 ,even to this day such materials are used to obtain certain effects in special instances4 ,the idea of employing mineral chemicals undoubtedly originated in the textile-dyeing industry1 which at one time was dependent to an appreciable extent on mineral substances for the production of certain fast shades4 ,compounds of iron1 lead1 manganese1 also of copper1 cobalt and nickel were all used for dyeing1 either singly or in various combinations4 ,in the application on furs1 the brush method was the only one practicable1 as the skins would have been ruined by dipping them into solutions of these chemicals in the concentrations necessary for dyeing4 ,the dyeing of furs with mineral colors involves the precipitation on the fibre in a more or less permanent form of the sulphide1 oxide or other insoluble compound of a metal1 and can be brought about in several ways4 ,by what is known as double decomposition1 that is1 by the use of two solutions successively applied1 the ingredient of one causing a precipitate to form when in contact with the constituent of the second1 the color is produced on the hair4 ,another method is to use solutions of chemicals which decompose on contact with the hair1 forming an insoluble compound4 ,in the first method the hair is alternately treated with the two solutions of the requisite chemicals1 drying between each brushing1 the process being repeated until the desired shade is obtained4 ,the second method merely requires the solution of the chemical to be applied to the hair1 which is then dried1 the color forming by itself4 ,one of the most important of the mineral dyes1 and which is occasionally used to this day1 is lead sulphide1 formed by the double decomposition method by precipitating a soluble lead salt with ammonium sulphide1 or any other alkaline sulphide4 ,by simply brushing an aqueous solution of lead acetate1 also known as sugar of lead1 on a white fur such as white hare or rabbit1 a light1 brownish coloration is obtained due to the combination of the lead with the sulphur of the hair4 ,if the lead solution is carefully applied several times on this type of fur1 until a sufficiently dark color is produced1 it is possible to get a fairly good imitation of the stone marten4 ,the brown color is very fast1 being actually formed within the hair4 ,in most cases1 however1 for dyeing lead sulphide shades it is necessary to use the two solutions4 ,thus the pale greyish or slightly brownish-grey shades of the lynx can be reproduced on white rabbit or hare by this process4 ,a solution containing #fj grams of lead acetate per liter of water is brushed on to the hair of the fur which has previously been killed in the usual manner1 and the hair is then dried4 ,a solution of #ej grams of ammonium sulphide per liter of water is next brushed on1 and the fur again dried4 ,care must be exercised in handling the ammonium sulphide as it is a very malodorous liquid1 the fumes of which are poisonous when inhaled4 ,the alternate brushings are repeated until the desired depth of shade is obtained4 ,a very dark brown1 approaching a black can be obtained in this way4 ,this color can be used for the production of certain attractive effects4 ,by brushing over the tips of the hair1 which has previously been dyed a dark brown by means of the lead sulphide color1 with a dilute solution of hydrochloric acid1 or with peroxide of hydrogen1 the hair will become white in the parts so treated1 due to the formation of lead chloride or lead sulphate1 respectively4 ,thus white tipped furs can be obtained1 but the process is applicable only when the furs have been dyed by the lead sulphide method4 ,potassium permanganate is occasionally used to produce dyeings of a brown shade on furs4 ,considerable care has to be taken in applying this substance1 as it is possible to affect the hair4 ,the strength of the solution must be varied according as the hair to be dyed is weak or strong4 ,a cold solution of #aj to #bj grams of potassium permanganate per liter of water is brushed on to the hair1 which is then dried4 ,a brown precipitate of manganese is formed on the hair after a short time1 and the process is repeated until the required shade is obtained4 ,for furs with harder hair1 stronger solutions can be used4 ,the dyeing is very fast1 but it is seldom used1 cheaper and better shades being obtained in other ways4 ,spotted white effects can be produced on the brown dyeing with permanganate of potash by applying a solution of sodium bisulphite1 the brown color being dissolved by this chemical4 ,the compounds of other metals1 such as iron1 copper1 cobalt and nickel are not used in practise as the dyeings are not fast1 and can be better produced in other ways4 ,,chapter ,,xiii ,,fur ,,dyeing ,,vegetable ,,dyes ,with the exception of the few shades which could be produced solely by means of coloring matters of a chemical character1 all dyeings on furs up to about thirty years ago were made with dye substances obtained from the vegetable kingdom1 either alone1 or in conjunction with the aforementioned mineral colors4 ,the colors of vegetable origin used in comparatively recent times were mainly extracts of the wood of certain trees2 so the name 8wood dyes0 has come to be applied generally to the dyes of this class4 ,the use of the vegetable or natural dyes on furs dates back to quite ancient times1 as frequent allusions and descriptions in ,biblical and other contemporaneous literature testify4 ,there are numerous pictures on monuments and tablets illustrating the dyeing of furs among the ancient ,egyptians1 the evidence indicating that the juice of certain berries1 and extracts of certain leaves were used for the purpose4 ,at a later period1 in the ,roman era1 henna1 which was used over two thousand years ago as to-day for the beautification of the hair of women1 was also used to color fur skins4 ,the instances cited here are merely of scientific and historical interest1 and are not of practical importance as far as fur dyeing methods are concerned4 ,it was not until many centuries later that the dyeing of furs took on the aspects of a commercial art1 and the substances then employed were chiefly tannin-containing materials such as gall-nuts and sumach1 which in conjunction with certain metallic salts1 particularly those of iron1 were capable of producing dark shades4 ,the use of iron compounds to form dark grey or black colors on leather tanned by means of the tannins1 had been common for a long time1 and it was natural that fur dyers should try to produce such shades on furs in a similar fashion4 ,the use of the iron-tannin compound as a dye proved to be very effective1 and to this day the production of blacks by means of the vegetable coloring matters has as a basis an iron-tannate4 ,a formula in common use in the latter seventeenth and the eighteenth centuries for producing black shades on furs1 is the following3 ,lime water #aaag parts ,gall-nuts #aejj ,litharge #ejj ,salammoniac #fe ,alum #abh ,verdigris #fd ,antimony #fd ,minium #cb ,iron filings #abh ,green copperas #chd ,all these substances except the gall-nuts1 the copperas and half the lime water were boiled up in a cauldron2 then the gall-nuts and the copperas were placed in a bucket and the contents of the cauldron poured in1 and the rest of the lime water added4 ,the mixture was stirred up1 allowed to settle for an hour1 and when cool1 was ready to be applied by the brush method4 ,for dyeing by the dip process1 a similar mixture was used1 only considerably diluted with water4 ,a study of the formula discloses the fact that in it are combined killing and mordanting substances as well as dyeing materials4 ,the lime water1 in conjunction with the salammoniac serves as a killing agent1 the verdigris1 copperas and alum are mordants1 while the litharge and the minium1 both compounds of lead1 could possibly act as mineral dyes1 and the iron filings and the antimony took virtually no part at all in the dyeing1 except1 perhaps to act in a mechanical way4 ,the formulas for other shades were made up along similar lines1 the chief constituent of vegetable nature being either gall-nuts1 sumach1 or both4 ,a mixture for a chestnut brown1 for example1 contained gall-nuts1 sumach1 and the various other mineral constituents as in the black dye1 litharge1 alum1 copperas1 verdigris1 salammoniac1 antimony1 and in addition1 red lead and white lead4 ,it is evident in both these instances that the shade obtained was as much the result of mineral dyeing as of vegetable dyeing4 ,the discovery of ,america introduced into ,europe many new dye substances1 chiefly wood extracts such as logwood and ,brazilwood1 but it was not until the nineteenth century that these materials found their way into the dye formulas of the fur dyer4 ,most of the processes used in the dyeing of furs were adaptations of methods employed in silk dyeing1 the silk fibre being considered as most nearly approaching fur-hair in nature and characteristics4 ,by devious and circuitous paths the formulas of the silk dyers reached the fur people1 and so1 in the middle of the nineteenth century1 dye mixtures containing the various dyewoods as well as the tannin-containing substances were in general use for the dyeing of furs4 ,the following is a typical recipe of that time for the production of black on furs like wolf1 skunk1 raccoon1 etc43 ,roasted gall-nuts #ajjj parts ,sumach #bjj ,iron mordant #bjj ,copper vitriol #ajj ,litharge #hj ,alum #fj ,salammoniac #ej ,crystallized verdigris #dj ,french logwood extract #cj ,rain water #gjjj ,the mixture was boiled up1 and after cooling was ready for application by the brush method1 the skins being first killed by a killing mixture also applied by the brush4 ,the dye substances in this case are the gall-nuts1 sumach and the logwood extract1 with the iron mordant1 copper vitriol1 and alum as mordants4 ,for brown shades a similar formula was used containing ,pernambuco wood extract1 logwood extract1 quercitron bark1 gall-nuts and dragonblood1 together with iron1 copper and alum mordants4 ,formulas such as the above were mainly empirical1 that is1 they were compounded as a result of trial of various combinations of the constituents1 without considering the nature and quantitative character of the reactions1 as long as the desired shades could be obtained4 ,such dye mixtures were frequently found to yield results varying from those expected or originally obtained1 because the effectiveness of the formulas depended upon the exact duplication in every detail1 of conditions which had given satisfactory results previously1 and it was not always possible to attain such an accurate reproduction of circumstances1 especially when the fur dyers were quite ignorant of the scientific relationships of the materials used4 ,so when more light had been shed on the nature and chemical characteristics of the vegetable dye substances1 formulas like those described were no longer employed1 although the essential ingredients were the same in the new processes4 ,unnecessary constituents were eliminated1 and proper ones substituted where it was required1 and the quantities of the materials used were made to conform to the chemical laws governing the reactions4 ,since these new formulas were based on a rational understanding of the constituents and their reactions1 it is desirable to study the latter briefly1 before further discussing the formulas themselves4 ,the substances of vegetable origin used in modern fur dyeing may be grouped into two classes1 one1 the tannin-containing materials1 and the other1 the dyewoods proper4 ,the most important of the tannins are gall-nuts1 sumach and chestnut extract4 ,cutch1 which also comes under this class1 is more frequently used for the production of brown shades1 so it is grouped with the dyewoods4 ,among the latter are logwood1 fustic1 ,brazilwood1 quercitron1 turmeric1 and several others of less significance4 #a4 ,tannin ,materials ,first and foremost under this heading are the nutgalls4 ,these are ball-shaped excrescences produced on certain plants by the punctures of insects in depositing their eggs4 ,there are two chief varieties1 the ,european1 and the ,chinese4 ,the ,european galls are formed by the female gall-wasp which drops an egg in the rind of young branches of certain oaks4 ,a swelling 7the nutgall7 is produced1 in which the young insect develops1 and from which it finally escapes by piercing a hole through the shell4 ,those galls which are not pierced have a fresh bluish or green color1 are heavy and contain most tannic acid4 ,after the insect has gone out1 the galls are of a lighter1 yellowish color1 and also of inferior quality4 ,the best oak-galls are the ,aleppo1 and the ,turkish or ,levant galls1 containing #ee-fj of tannic acid1 and about #d of gallic acid4 ,the ,chinese galls are produced by the puncture of a plant-louse on the leaves and leaf-stalks of a species of sumach1 and not on oaks4 ,the galls are very light1 and very rich in tannic acid1 containing often as much as #hj4 ,for dyeing purposes1 nutgalls are usually ground to a powder1 and in some instances they are even roasted first and then ground4 ,sumach consists of the leaves and sometimes of the small twigs and stems of a species of sumach plant known as the ,rhus coriaria4 ,the ,sicilian variety is the finest commercial quality1 with the ,virginian ranking next4 ,it is sold as a powder1 but also in the form of the whole or crushed leaves4 ,the best sumach contains #ae-be of tannin4 ,extracts are also manufactured1 a liquid extract of #eb degrees ,twaddell1 which forms a dark brown1 thick paste2 and a solid extract1 formed by evaporating the liquid extract to dryness4 ,chestnut extract is prepared from the wood of the chestnut oak1 which contains #h-aj of tannin4 ,the solid extract has a bright1 black color1 while the liquid extract is a dark brown paste with a smell like that of burnt sugar4 ,the tannins all give greyish to black shades with iron salts1 and it is this fact which renders them important for fur dyeing4 #b4 ,wood dyes ,one of the most important of all the natural dye substances1 especially for the production of blacks1 is logwood4 ,the color is really a red1 but with the common mordants it forms blue1 violet or black shades4 ,logwood1 or campeachy wood1 as it is sometimes called1 is the product of a large tree growing in the ,west ,indies1 and ,central and ,south ,america4 ,when freshly cut1 the wood is practically without color1 but when exposed to the air it soon becomes a dark reddish-brown on the surface4 ,the coloring principle of logwood is called hematoxylin1 which is a colorless substance when pure1 and is of itself incapable of dyeing2 but when it is exposed to the air1 especially when moist and in the presence of some alkaline substance1 it is converted into hematein1 which is the real coloring matter of logwood4 ,to prepare the wood for use1 the logs are chipped or rasped1 the chips being heaped up and moistened with water4 ,fermentation occurs1 and the heaps are frequently turned to allow free access of air to the wood1 and to prevent overheating4 ,as a result of this process1 a great part of the hematoxylin is converted to the hematein4 ,the logwood may be used for dyeing in this state as chips1 but logwood extracts can now be obtained of a high degree of purity and are easier to work with4 ,the commercial forms of the extract1 are the liquid of #ea degrees ,twaddell1 and the solid extract4 ,hematein crystals can also be obtained4 ,all these extracts contain mainly hematein1 together with a small percentage of hematoxylin which is converted to the former during the dyeing process4 ,logwood is never used as a direct dye1 but is used to form color lakes with the various mordants1 the following colors being produced3 ,iron mordants give grey to black shades ,copper mordants give green-blue to black shades ,chrome mordants give blue to black shades ,aluminum mordants give violet shades ,tin mordants give purple shades ,by combining several of the mordants1 any desired shade of black can be obtained1 and if other dyewoods are used in conjunction with the logwood1 the range can be further increased4 ,fustic1 yellow-wood1 or ,cuba wood1 as it is variously called1 is obtained from a tree also growing in the ,west ,indies1 ,central and ,south ,america4 ,it is used either as wood chips1 or as a paste extract of #ea degrees ,twaddell1 and occasionally as solid extract4 ,fustic contains two coloring matters1 morintannic acid1 possessing the characteristics of a tannin1 and which is quite soluble in water1 and morin1 which is rather insoluble1 and which settles out from the liquid extract4 ,fustic is the most important of the yellow dyes of natural origin1 and is used considerably in fur dyeing with logwood for shading the blacks1 or for producing compound shades4 ,with the usual mordants fustic gives the following colors3 ,with iron salts dark olive ,with copper salts olive ,with chrome salts olive-yellow to brownish-yellow ,with aluminum salts yellow ,with tin salts bright yellow to orange-yellow ,brazilwood1 or redwood1 is the product of a tree found in ,brazil1 and exists in several varieties1 such as peach wood1 ,sapan wood1 ,lima wood1 and ,pernambuco wood4 ,they all yield similar shades with the various mordants1 and all seem to contain the same coloring principle1 brasilin1 which1 like the hematoxylin1 has no dyeing power1 but by fermentation and oxidation it is converted to brasilein1 corresponding to the formation of hematein4 ,brazilwood and the related woods are used either as chips or extract1 but seldom alone1 usually in conjunction with other dyewoods4 ,by combining logwood1 fustic and ,brazilwood in various proportions1 and by employing suitable mordants1 all the shades required by the fur dyer can easily be produced4 ,quercitron is the inner bark of a species of oak 7,quercus tinctoria7 found in the ,united ,states4 ,it contains two coloring principles1 quercetrin and quercetin4 ,the fresh decoction of quercitron bark is a transparent dull orange-red which soon becomes turbid and deposits a yellow crystalline mass4 ,it is generally used in conjunction with other dyes4 ,cutch is the dried extract obtained from a species of acacia1 the principal varieties being ,bombay1 ,bengal1 and ,gambier cutch4 ,it contains two coloring principles1 catechin and catechu-tannic acid4 ,cutch acts as a tannin1 and like other tannins discussed above1 can be used for the production of grey or black shades with iron mordants4 ,it is employed chiefly1 however1 for dyeing browns4 ,aluminum salts give with cutch a yellowish-brown1 tin salts give a lighter yellow1 copperas gives a brownish-grey1 and chrome and copper salts give brown shades4 ,turmeric is the underground stem of the ,curcuma tinctoria1 the coloring principle being called curcumin4 ,it may be used as a direct dye1 but usually a mordant is used4 ,turmeric is sometimes used in place of fustic4 ,while the tannins can be used alone with an iron mordant for producing greyish to black shades1 the dyewoods alone yield colors which would be too bright to be suitable for dyeing furs4 ,in order to tone down this brightness1 and to give to the dyeings that greyish undertone which is characteristic of the natural furs1 and which can only be imitated by means of the iron-tannin compound1 it is customary to combine the tannins with the wood dyes4 ,the iron-tannate constitutes the foundation of the color which gets its intensity1 and necessary brilliancy and bloom from the wood dyes4 ,moreover1 the presence of the iron-tannin compound helps considerably to increase the fastness of the dyeing4 ,furs dyed with the combination of the tannins and the wood dyes obtain an additional tanning treatment which materially improves the quality of the leather1 for not only do the tannin substances exert this tanning action1 but the dyewoods as well1 for they are themselves either of the nature of tannins1 or contain a coloring principle which is a tannin4 ,it is to the combined effects of the tannin substances and the dyewoods that furs dyed with vegetable dyes owe their beauty of color1 lustre1 naturalness of shade1 permanence of the dyeing1 and durability of the leather4 ,wood dyeings on furs have for this reason acquired a just renown1 but owing to the introduction of the new kinds of fur dyes1 the use of the vegetable dye substances has been greatly reduced4 ,the dyes of vegetable origin can be applied to furs by either the brush method or the dip method1 or both1 and since mordants are required with the dyes of this class1 they are applied in one of the three ways mentioned in a previous chapter3 first1 by mordanting before dyeing2 second1 by applying mordant and dye simultaneously2 and third1 by mordanting after the skins have been treated with the dye4 ,i4 ,,dyeing ,,with ,,vegetable ,,dyes ,,by ,,the ,,brush ,,method ,the use of the brush method in applying the natural dyes to furs is limited to a comparatively few kinds of dyeing1 namely to produce special effects on furs1 or to give to the upper-hair of furs a coat of dye different from the base color4 ,in a quite recent ,german patent is described a process for blending a red fox as a silver fox and the procedure affords a good example of brush dyeing with preliminary mordanting4 ,the specification is as follows3 8,d4 ,r4 ,p4 #caj1 #dbe 7#aiah74 ,a process for dyeing red fox as silver fox4 ,the tanned and dressed skin is first superficially decolorized by applying a dilute mixture of milk of lime1 iron vitriol and alum1 with a soft brush so as only to penetrate the top-hair4 ,allow to remain for #d-f hours1 dry1 and beat out the dust4 ,a dilute solution of iron vitriol is brushed on so as only to wet the top-hair1 and the skin is thus allowed to remain moist for #ab-bd hours4 ,then without drying1 a solution of iron vitriol1 salammoniac1 litharge1 red argol and wood ashes is brushed on cold with a hard brush so as to penetrate all the hair down to very near the skin4 ,the skin has now completely lost its red color1 and has become a pale yellow4 ,it is now ready to be dyed4 ,an infusion of roasted nutgalls1 which have been boiled for #c-d hours with water1 is applied cold with a soft brush to the upper hair4 ,allow to remain so for #b-c hours1 and without drying1 apply a weaker solution of the roasted nutgalls with a hard brush so as to saturate the hair thoroughly4 ,dry and beat out4 ,according to the concentration of the solution applied1 the hair will be colored blue-grey to black1 and the shade can be varied by varying the strength of the solutions used4 ,the different parts of the skin1 or those parts of different shades can be dyed accordingly40 ,in this patent all the operations1 including killing1 mordanting and dyeing are done by the brush method1 and the process1 from this point of view is quite similar to one which might have been employed a century previous4 ,it is evident that the time and effort required to carry out the details as described in the patent would only be warranted in exceptional cases1 where the value of the dyed fur would be considerably greater than that of the natural skin4 ,an example of the application at the same time of dye and mordant by the brush method is the original ,french ,seal dye1 which is still employed to a limited extent to produce a brilliant1 deep1 lustrous black topping on furs which have already been dyed by the dip process4 ,a typical formula for the old ,french ,seal dye is the following3 ,green copperas #aj parts ,alum #aj ,verdigris #aj ,gall-nuts #hj ,logwood extract 7#ae degrees ,twaddell7 #aej ,water #ajjj ,this mixture is applied to the top of the hair of the furs1 after previous killing1 and the skins allowed to remain moist for several hours1 and also exposed to the air4 ,the skins are then dried1 and beaten out1 and if necessary a second coat of dye is brushed on4 ,in dyeing seal-imitation on muskrat1 or skunk-imitation on opossum1 for example1 the black color required on the top-hair1 or the upper part of the hair when the furs are sheared1 can be produced by applying a mixture similar to the above1 to the furs after they have received their base color by the dip process with natural dyes or with the ,oxidation ,colors4 ,occasionally1 the dyeing is given an after-treatment with a dilute solution of sodium bichromate to help develop the color1 the action in this case being that of an oxidizing agent1 and not of a mordant4 ,as far as the third method of mordanting is concerned1 that of first applying the dye1 and then the mordant1 it is rarely practised with the brush method4 ,the procedure1 however1 consists in first brushing on a solution of the desired dye1 then drying and brushing on a mordant solution4 ,these operations are repeated perhaps two or three times until the proper shade is obtained1 exposing the furs to the air for the color to be developed4 ,,ii4 ,,dyeing ,,with ,,vegetable ,,dyes ,,by ,,the ,,dip ,,method ,it was in the application to furs by the dip process that the use of the vegetable dyes attained great importance1 and although at the present time1 natural organic dyes have largely been superseded by the ,oxidation ,colors and ,aniline ,black dyes1 yet for certain purposes1 and especially for the production of blacks1 the wood dyes still are able to hold their own4 ,the dyeing of black formerly constituted probably the most important branch of the fur dyeing industry1 and was undoubtedly the most difficult one4 ,for it is possible to obtain as many different kinds of black as there are dyers of this color1 but only a few certain shades are desirable4 ,the division of the classes of furs into those derived from the various kinds of sheep1 and those obtained from other animals is particularly marked in the dyeing of black1 and both the composition of the dye formulas and the methods of dyeing are somewhat different for the two groups4 ,for the dyeing of black on ,persian lambs1 broadtails1 caraculs1 etc41 a combination of logwood and nutgalls with the requisite mordants is used1 while on hares1 ,chinese sheep1 foxes1 raccoons1 opossum1 etc41 a mixture of logwood and turmeric or fustic1 with the proper mordants is used4 ,the general procedure is as follows3 ,the dye substances to be used are ground up to a powder in a mill constructed for the purpose1 after which they are boiled with water in a copper-lined kettle or cauldron1 heated from the outside by steam4 ,the customary arrangement is to have a jacketed kettle1 supported on a stand1 and having taps and valves to enable the liquor to be drawn off1 or pivoted1 so that the kettle can be tilted1 and the contents poured out4 ,the use of the copper-lined vessel is to be preferred1 as it is unaffected by any of the dye substances1 and so cannot cause any rust stains4 ,after the dyes have gone into solution and have cooled1 the mordant chemicals1 previously dissolved in water1 are added1 and the mixture stirred up4 ,the dyeing in this instance is effected by the simultaneous application of dye and mordant4 ,the dye mixture is now run off1 or poured out in the proper quantity into a number of small vats of #be-cj gallon capacity1 or into a paddle vat1 which can be closed1 while the paddle is rotating4 ,the latter device is to be preferred because it permits the dye to retain its temperature better and for a longer period of time1 but when lambs are being dyed only the open vats are used4 ,the temperature of the dye mixture is between #dj and #de ,c41 for only at this temperature can the hair absorb the dye properly without injuring the leather4 ,the killed skins are immersed in the dyebath for a time1 usually overnight1 after which they are removed1 drained and hung up1 with the hair-side exposed to the air1 so as to permit the dye to develop1 which takes place with the aid of the atmospheric oxygen4 ,the dyebath is again brought to the proper temperature1 and the skins are again entered1 to go through the same process as often as is necessary to obtain the desired depth of shade4 ,the dyed skins are thoroughly washed to remove excess dye1 then dried and finished4 ,the following are a few dye formulas used in the production of blacks3 ,logwood extract #ajj grams ,chestnut extract #ad c4c4 ,turmeric #ch grams ,iron acetate #f ,b4 #ej c4c4 ,water #abjj c4c4 or1 ,cutch #ae grams ,soda #ad grams ,logwood extract #abj grams ,verdigris #ai grams ,iron acetate #e ,b4 #af c4c4 ,water #abjj c4c4 ,a recently published formula for dyeing ,china goat skins black1 is the following3 ,dissolve #ej lbs4 of dark turmeric and #de lbs4 of logwood extract and make up to #cjj gallons of solution1 at #ie ,f4 ,enter the killed skins and leave them in the liquor until they rise to the surface4 ,then take them out and add #be lbs4 of logwood extract1 #aj lbs4 of sumach1 #aj lbs4 of blue vitriol1 #e lbs4 of fustic extract1 and about #fj lbs4 of iron acetate liquor4 ,stir up well1 and immerse the skins for #ah hours4 ,draw them up1 and expose to the air for #ab hours4 ,heat the liquor again to #ie ,f4 and put the skins back for #ab hours4 ,draw out1 hang up in the air for a time1 then wash thoroughly1 hydro-extract1 dry and finish4 ,in a ,german patent1 ,d4 ,r4 ,p4 #ajg1gag 7#ahih71 is described a method for dyeing lambs black1 consisting in treating the skins for #bd hours in a logwood bath1 then rinsing in cold water1 and mordanting for #ae hours in a solution of bichromate of potash4 ,the skins are then washed and treated with a solution of iron salt1 then dried4 ,this process1 while of not much practical importance1 is an illustration of mordanting subsequent to the dyeing treatment4 ,as far as the production of other shades is concerned1 the procedure is quite similar to the regular black method4 ,for a dark brown1 for example1 the skins are dyed in a mixture containing ,gall-nuts #dj parts ,verdigris #aj ,alum #aj ,copperas #e ,brazilwood extract 7#ae ,twaddell7 #aej ,water #ajjj employing operations just as in the case of the black4 ,greyish-blue shades on white hares1 lambs1 kids1 etc41 can be obtained by treating the skins successively in the following baths3 #a4 ,logwood extract #ajj grams ,water #a liter #b4 ,indigotine #aj grams ,alum #aj grams ,water #a liter ,bluish-grey tones on the same furs can be produced by treating with #a4 ,logwood extract #bjj grams ,indigotine #ae grams ,water #a liter #b4 ,alum #aej grams ,salammoniac #ab grams ,water #a liter ,similar grey shades can be produced by mordanting the skins with an iron salt1 and then dyeing in a weak bath containing gall-nuts1 sumach and iron vitriol4 ,this method is very effective for making ,alaska or silver fox imitations4 ,,chapter ,,xiv ,,fur ,,dyeing ,,aniline ,,black ,fur seal for a long time has been a fur of distinction and importance in the fur industry1 and consequently the dyeing of seal has constituted an important1 though not very extensive branch of the art of fur dyeing4 ,in quite recent times the popularity of seal has become so great that imitations have had to be produced to help supply the demand1 and as a result1 ,french seal1 or seal-dyed rabbit1 and the so-called ,hudson seal1 which is seal-dyed muskrat1 have acquired a great vogue4 ,occasionally opossum1 nutria and other furs are also used for the purpose of producing seal imitations4 ,while the supply of real seals is relatively small1 and the demand large1 the production of seal imitations has assumed large proportions1 and as a result1 the dyeing of seal and its imitations or substitutes has come to be a great branch of the fur dyeing industry4 ,during the past thirty years1 the long and tedious processes of dyeing seal and seal imitations1 involving the use of dyes of vegetable origin1 have largely been superseded by what is known as the ,aniline ,black dye4 ,it was the ,french who first worked out successfully the application of ,aniline ,black to furs1 and the method has attained much importance and extensive use in the fur dyeing industry4 ,aniline ,black is the name given to an insoluble black dyestuff produced by the oxidation of aniline in an acid medium4 ,as a finished product it cannot be used in fur dyeing1 but if the hair of the furs be impregnated with a suitable preparation of aniline and then treated with certain oxidizing agents1 the color will be formed on the hair1 being firmly fixed and giving a fast black1 resistant to light1 washing and rubbing4 ,the basis of the dye1 aniline1 is an oily liquid1 possessing a peculiar fishy odor1 colorless when pure1 but rapidly turning brown when exposed to the air4 ,it is obtained from benzol1 which is distilled from coal-tar1 by treating with nitric acid1 forming nitrobenzol1 which when subjected to the action of reducing chemicals is converted into aniline4 ,the process may be shown schematically as follows3 ,coal--coal-tar--benzol--nitrobenzol--an iline oil--,aniline ,black4 ,aniline ,black was by no means a new dye when the ,french succeeded in producing it on furs4 ,it had been used for a long time previous on textiles1 chiefly cotton4 ,the history of the development of the ,aniline ,black process throws considerable light on its nature and constitution1 and so presents many features of interest4 ,as early as #ahcd1 the chemist ,runge observed the formation of a dark green color when heated aniline nitrate in the presence of cupric chloride4 ,fritsche1 in #ahdj1 noticed that when chromic acid was added to solutions of aniline salt1 a dark green1 and sometimes a blue-black precipitate was produced1 and later the same chemist obtained a deep blue by the action of potassium chlorate on aniline salt4 ,it is interesting to note that ,perkin1 in #ahef1 conducting similar experiments on the oxidation of aniline with chromic acid1 obtained a blue-black product from which he extracted the first synthetic coal-tar dye1 mauve4 ,thus far1 all the experiments on the oxidation of aniline proved to be merely of scientific interest1 but in #ahfb1 ,lightfoot patented a process for the practical application of colors formed by the oxidation of aniline on the fibre1 a greenish shade being obtained by that method1 to which the name emeraldine was given1 and by subsequent treatment with bichromate of potash1 the green was changed to a deep blue color4 ,since that time1 the methods for producing and applying ,aniline ,black have been developed and improved1 although all the processes were based on the principles incorporated in ,lightfoot's original patent4 ,however1 it was not until the last decade of the nineteenth century that the dyeing of furs by means of the ,aniline ,black method was successfully attempted4 ,a knowledge of the nature and the manner of the chemical changes which take place in the production of ,aniline ,black is a valuable aid in obtaining satisfactory results in practise2 and although ,aniline ,black was extensively used before the true character of the reaction was understood1 since the successful determination of the constitution of ,aniline ,black and the discovery of the real nature of the process by ,green and his collaborators in #aiac1 the methods have been considerably improved and simplified1 with correspondingly better results in dyeing4 ,as a consequence1 the methods of dyeing furs with ,aniline ,black have also become simpler and more efficient4 ,a discussion of the chemical changes which occur in the ,aniline ,black process1 is out of place here on account of the highly involved and complicated character of the reactions1 to understand which requires a considerable knowledge of specialized organic chemistry4 ,but the essential features of practical importance in the production of ,aniline ,black are the following3 ,as already noted1 one of the characteristic properties of aniline is its tendency to turn from a colorless to a dark-brown liquid in the presence of the air4 ,this change is due1 together with certain other causes1 to an oxidation brought about by atmospheric oxygen4 ,by employing oxidizing agents1 this oxidation can be accelerated and carried further1 and eventually the ,aniline ,black is obtained4 ,among the substances which may be used to bring about the conversion of aniline to the insoluble black dye are manganese dioxide1 lead peroxide1 hydrogen peroxide1 chromic acid1 ferric salts1 potassium permanganate1 chloric acid and chlorates in the presence of certain metallic salts1 particularly those of vanadium and copper4 ,chlorates1 especially sodium chlorate and potassium chlorate1 are the most commonly employed oxidizing agents1 bichromate of soda or of potash being used1 in addition1 to complete the oxidation4 ,when using chlorates it is necessary to have present in the dye mixture a small quantity of a metallic salt1 which1 while not entering into the reaction itself1 is nevertheless indispensable as an oxygen carrier4 ,vanadium compounds have proved to be the most effective for this purpose1 and according to an authority1 one part of vanadium salt is sufficient to cause the conversion of #bgj1jjj parts of aniline to ,aniline ,black1 the necessary amount of a chlorate being present of course4 ,salts of copper1 cerium1 and iron are also extensively used1 but they are not quite so efficient as vanadium4 ,the formation of the ,aniline ,black in practise takes place in three well-defined steps1 which it is important to be able to recognize and distinguish in order to obtain the best results4 ,the first stage of the oxidizing process produces what is called emeraldine1 which in the acid medium of the aniline bath is of a dark green1 while in the free state it is of a blue color4 ,as the oxidation proceeds1 the second stage develops1 the emeraldine being converted to a compound called nigraniline4 ,this in acid solution is blue1 and the free base is a dark-blue1 almost black4 ,it was formerly considered that the nigraniline was the ,aniline ,black proper1 and so when this stage of the oxidation was reached1 the process was often interrupted and not carried to the limit4 ,this can account for the fact that ,aniline ,black dyeings usually turned green after a short time4 ,the reason for this is that nigraniline1 when treated with weak reducing agents1 as1 for example1 sulphurous acid1 is at once changed to emeraldine1 with its dark green color4 ,since there is usually a small amount of sulphurous acid in the air1 especially in places where coal or gas is burned1 an ,aniline ,black dyeing which has not been carried beyond the nigraniline stage will be reduced in time to the emeraldine1 and cause the dyeing to become green4 ,the last step in the oxidation changes the nigraniline into what is properly called the ungreenable ,aniline ,black4 ,weak reducing substances like sulphurous acid do not change this compound to emeraldine1 and stronger reducing agents only convert it to a brownish compound1 which changes back to the black when exposed to the air4 ,it is quite evident that in order to obtain a black which will not change to green in time1 the oxidation of the aniline must be carried to the last stage4 ,by making tests during the dyeing of the furs1 it can easily be determined whether the oxidation has proceeded far enough4 ,in the dyeing of textiles with ,aniline ,black1 it is customary to carry out the operation at comparatively high temperatures1 approaching #ajj centigrade4 ,with furs such temperatures are out of the question1 so it is necessary to repeat the dyeing several times in order to obtain the proper depth of shade working in the cold4 ,only the brush method can be used in applying the ,aniline ,black dye to furs1 on account of the strong acidity of the dye mixture1 which would ruin the leather1 if the dyeing were done in a bath4 ,indeed1 great care must be exercised even by the brush method to avoid too great penetration of the dye liquid1 otherwise the roots of the hair will be attacked1 and the leather may be 8burned0 from the hair side4 ,furs dyed with ,aniline ,black are frequently after-dyed by the dip-process with logwood or some other similar dye1 in order to add to the brilliancy of the dyeing4 ,combined with intensity of color1 ,aniline ,black on furs is the only dye which will also give fast1 lustrous shades1 and leave the hair soft and smooth4 ,there are several methods of applying ,aniline ,black on furs1 the most important being #a4 ,one-bath ,aniline ,black #b4 ,oxidation ,aniline ,black #c4 ,diphenyl ,black #d4 ,aniline ,black by ,green's ,process #a4 ,one-bath ,aniline ,black ,a typical formula for this method is the following given by ,beltzer3 ,aniline salt #aj kg4 ,sodium chlorate #a4e kg4 ,copper sulphate #j4g kg4 ,vanadate of ammonia #aj gr4 ,all these substances are dissolved hot in #ej liters of water1 and allowed to cool1 forming solution ,a4 ,aniline salt is aniline oil which has been neutralized with the exact quantity of hydrochloric acid to form the hydrochloride4 ,it forms white or greyish crystalline lumps very easily soluble in water4 ,the sodium chlorate is the oxidizing agent1 and the copper sulphate and the vanadate of ammonia are the oxygen carriers4 #ae kg4 of sodium bichromate are also dissolved in #ej liters of water1 forming solution ,b4 ,the bichromate is also an oxidizing agent and serves to complete the oxidation of the aniline to the black4 ,immediately before using1 solutions ,a and ,b are mixed together1 both being cool4 ,in general practise it is customary to mix only small quantities at a time1 as a considerable precipitate forms when the whole batch is mixed at once1 the precipitate being so much waste dye substance4 ,usually a liter of ,a and a liter of ,b are mixed at a time1 and the furs brushed with the mixture4 ,the brushing must be varied according as the hair is hard and stiff1 or soft and tender4 ,the hair must be thoroughly impregnated in all directions1 and the penetration must not be too deep to affect the leather4 ,with experience and dexterity satisfactory results can easily be achieved4 ,after the skins have been properly treated1 they are dried at a temperature of about #ce degrees centigrade4 ,when dry1 they are returned to the dye bench1 where they receive another application of the dye mixture1 and are again dried4 ,this operation may be repeated as often as six or seven times before a sufficiently intense black is obtained4 ,another way of producing the desired depth of shade with fewer applications is by using more concentrated dye mixtures4 ,each method has its disadvantages1 the greater number of brushings requiring the expenditure of more time and labor1 and the greater concentration of the bath resulting in a considerable loss of dye substance due to the formation of a large precipitate when the two solutions are mixed1 and moreover1 not all furs can be treated with concentrated mixtures4 ,the best results with this method usually require the application of six coats of a mixture of moderate concentration4 #b4 ,oxidation ,aniline ,black ,in order to overcome the difficulty of employing very concentrated dye mixtures1 or of making many applications of the dye1 a method was devised whereby the two solutions of the previous process1 instead of being mixed together1 are applied successively to the hair of the furs1 the following formula1 also by ,beltzer1 being an example3 ,aniline oil #aj liters ,nitric acid #cf ,beaum1 or ,hydrochloric acid #bb ,beaum #bj liters ,cold water #bj liters ,this is solution ,a1 and is merely a solution of aniline hydrochloride1 or nitrate1 depending on which acid has been used4 ,nitric acid1 although more costly than the hydrochloric acid1 is to be preferred1 because it is an oxidizing acid1 and so assists in the oxidation of the aniline1 and besides1 has a more beneficial effect on the hair than the hydrochloric1 in the matter of softness and luster4 ,sodium chlorate #d kg4 ,copper sulphate #a kg4 ,vanadate of ammonia #aj gr4 ,water #ej liters ,this is solution ,b1 containing the oxidizing agent1 and the oxygen carriers4 ,just before using1 equal quantities of ,a and ,b are mixed1 and the skins brushed with the mixture4 ,the skins are then dried at #ce-de centigrade1 at which temperature the color begins to develop4 ,when almost1 but not entirely dried1 the skins are subjected to the action of warm vapor1 which is allowed to enter the drying chamber1 so as to keep the temperature about #dj centigrade1 the color developing better in this way4 ,this operation may be repeated1 or the skins are directly treated with a solution of #be kg4 of sodium bichromate in #ajj liters of water1 to complete the oxidation4 ,the moist skins are exposed to the air for a time1 and then dried at #ce ,c4 ,this method of dyeing has several advantages over the ,one-bath ,aniline ,black4 ,it requires fewer brushings1 and enables the complete utilization of the dye solutions without loss4 ,with three applications of the dye mixture by the ,oxidation process1 as deep and intense a black can be obtained as with six brushings by the ,one-bath method4 ,the dyeings1 too1 are nearly1 but not fully as brilliant and even as in the latter case4 ,the greater the number of coats of dye that are applied the more regular will the dyeing be4 #c4 ,diphenyl ,black ,in #aijb1 the ,farbwerke ,hoechst1 a large ,german producer of coal tar intermediates and dyes1 invented an ,aniline ,black process to which they gave the name ,diphenyl ,black4 ,the chief departure from the previous ,aniline ,black methods was the replacing of part of the aniline oil of the dye mixture by ,diphenyl ,black ,base ,i1 which is para-aminodiphenylamine4 ,this base has the property of being oxidized to ,aniline ,black1 just like aniline oil1 and the advantage claimed for the ,diphenyl ,black is that it produces an absolutely ungreenable black4 ,the method of application is practically the same as for the other ,aniline ,black processes1 chlorates being used as the oxidizing agents1 in the presence of oxygen carriers such as salts of copper and vanadium4 ,the use of bichromates is dispensed with4 ,on account of the comparatively high cost of the ,diphenyl ,black ,base ,i1 this method has not found very extensive application1 especially as highly satisfactory ungreenable blacks can now be produced by other methods4 #d4 ,aniline ,black by ,green's ,process ,in #aijg1 ,green1 who has done much work in the direction of elucidating the character of the ,aniline ,black process1 obtained a patent for a method of applying ,aniline ,black in a manner which was different from all the previously known formulas4 ,the invention created great interest1 and although in its original form it did not find a wide application1 many of the methods used at the present time are in one way or another derived from the idea of ,green4 ,a resum of the patent will therefore be given here3 8,the invention relates to the production of an ,aniline ,black1 the new process differing from all other known processes by the fact that the oxidation of aniline is effected solely or mainly by the oxygen of air4 ,the possibility of dispensing with an oxidizing agent depends on the discovery that the addition of a small quantity of a para-diamine1 or of a para-amido-phenol to a mixture containing aniline and a suitable oxygen carrier1 such as a salt of copper1 greatly accelerates the oxidation of the aniline by the atmospheric oxygen4 ,further1 whereas in the ordinary processes of ,aniline ,black1 the quantity of mineral acid employed cannot be materially reduced below the proportion of one equivalent to one equivalent of the base1 under the new conditions the mineral acid may be wholly or partially replaced by an organic acid such as formic acid1 without the quality of the black being materially affected4 ,as suitable oxygen carriers the chlorides of copper have been found to give the best results1 it being preferrable to use the copper in the form of a cuprous salt4 ,this is effected by adding to the dye mixture cupric chloride1 together with a sulphite or bisulphite in sufficient quantity to reduce the cupric salt to the cuprous state1 and a sufficient quantity of a soluble chloride to keep the cuprous chloride in solution4 ,among the compounds suitable for the production of this black in conjunction with aniline are1 para-phenylene-diamine1 dimethyl-para-phenylene-diamine1 para-amido-diphenylamine1 para-amido-phenol1 etc40 ,this method may be used alone as the other ,aniline ,blacks1 or the dyed skins may be after-dyed in a bath containing a logwood dye1 or it may be used in conjunction with mineral dyes1 or with the ,oxidation ,colors 7see next chapter74 ,a typical formula for the black by ,green's process is the following3 ,para-amido-phenol #j4e kg4 ,aniline oil #aj liters ,hydrochloric acid #bb ,b4 #aj liters ,acetic acid #dj #e liters ,cold water #be liters ,this is solution ,a4 ,solution ,b is prepared by dissolving ,copper sulphate #b kg4 ,salammoniac #aj kg4 ,cold water #ej liters ,a and ,b are mixed1 and the mixture applied to the hair of the furs several times1 drying each time at #ce-dj ,c4 ,after three coats of dye have been applied1 a pretty and fairly intense black shade is obtained1 which is developed further by treating with a solution of #be grams of sodium bichromate per liter of water4 ,the skins are then allowed to dry in air1 and then if desired1 an after-dyeing is made with some other dye4 ,on account of its extreme fastness1 ,aniline ,black1 produced by any of the methods outlined above1 has attained a justifiable popularity for the dyeing of furs1 in spite of the necessity of using the more or less cumbersome brush method of applying the dye4 ,very recently there was issued to a ,german company a patent in which is described a method whereby furs can be dyed with ,aniline ,black by the dip process4 ,an abstract of the patent 7,d4 ,r4 ,p4 #ccdjb7 is as follows3 8,as is known1 aniline salt1 and similar salts1 together with oxidizing agents like bichromates1 chlorates1 etc41 cannot be used for dyeing furs by the dip process1 because the strongly dissociated mineral acid is injurious to the leather4 ,the dissociation of the acid can be reduced by adding neutral salts1 like common salt1 or ,glauber's salt1 so that good results can be obtained by dyeing in a bath of the dye mixture1 the leather retaining its softness40 ,thus far there have been no reports of the successful practical application of this patent1 so its value cannot be discussed4 ,it is extremely doubtful1 however1 that furs will ever be dyed in the dyebath with the present type of ,aniline ,black formulas1 no matter what substances are added to prevent the leather from being affected4 ,,chapter ,,xv ,,fur ,,dyeing ,,oxidation ,,colors ,the year #ahhh may be considered the beginning of a new era in the history of fur dyeing2 the commencement of a period which was to see the time-honored1 traditional methods of the masters of the art give way to newer methods of an entirely different character2 and moreover1 the initiation of an age when science with its basis of fact and logic1 was to undertake the rationalization of an industry which had hitherto worked upon a more or less irrational1 empirical and uncertain comprehension of the fundamental principles involved4 ,it was not the work of a single day1 or even of a year which brought about the virtual revolution in the dyeing of furs1 but the result of long1 patient1 systematic effort4 ,about this time1 the ,german coal tar industry was attaining its real stride along the path of progress and achievement1 and had already succeeded in reaching1 to an appreciable degree at any rate1 most users of coloring matters1 with the consequence that the natural dyes1 with their time and labor-consuming processes of application were gradually being superseded by the new synthetic dyestuffs which could be simply and quickly applied4 ,it was now the turn of the fur dyeing industry to receive the attention of the scientists and technologists responsible for the growth of the coal tar dye industry1 and so there appeared in the above-mentioned year1 the following patents1 taken out by a ,german chemist named ,erdmann3 ,d4 ,r4 ,p4 #dgcdi ,a ,process for ,dyeing ,hair and ,feathers ,if white hair or feathers are soaked in an aqueous or alcoholic solution of para-phenylene-diamine1 and then exposed to the slow oxidation of the air1 or are treated in a second solution with some oxidizing agent1 then the hair or feathers will be dyed4 ,according to the oxidizing agent chosen1 and the concentration of the solution used1 the color obtained will be light or dark1 varying from the palest blond to the deepest blue-black4 ,particularly suitable as oxidizing substances are ferric chloride1 permanganates1 chlorates1 hypochlorites1 bichromates1 and hydrogen peroxide4 ,the dyeings are fast1 that is1 they do not come off1 and the color cannot be removed by washing4 ,following examples may serve to make the process clear3 #bj grams pure para-phenylene-diamine and #ad grams caustic soda are dissolved in a liter of water4 ,the hair1 previously degreased1 is soaked thoroughly in this solution1 and while moist is entered into a three per cent solution of peroxide of hydrogen4 ,the action is not instantaneous1 but after a day1 the hair is dyed a dark shade2 by repetition of these operations a blue-black is obtained4 ,the para-phenylene-diamine can be replaced in this process by other similar bases1 such as dimethyl-para-phenylene-diamine1 as well as the naphthylene-diamines4 ,since the substances which can be applied by this process are uninjurious1 the method described can be used to dye human hair on the head or beard1 and so seems suited to replace for the dyeing of hair1 the metallic salts and various pyrogallic solutions which are on the market1 and which are harmful to the health4 ,d4 ,r4 ,p4 #eajgc ,supplement to #dgcdi2 ,process for ,dyeing ,hair ,this patent was an extension of the original patent to include certain oxy and amido-oxy compounds1 the method being essentially the same otherwise as in the original patent4 ,an illustration of the process is as follows3 #gc grams para-amido phenol hydrochloride are dissolved with #dj grams caustic soda in a liter of water4 ,the solution dyes hair a golden-yellow1 which on subsequent treatment with a solution of ferric chloride turns to a red-brown4 ,in these two patents is to be found the basis of the modern fur dyes and fur dyeing methods4 ,it is interesting to note that furs were not mentioned at all in connection with the process1 which was intended mainly for dyeing hair1 especially on the human head4 ,it was only several years later that the value of the method for dyeing furs was realized4 ,so about #ahid1 the ,aktien ,gesellschaft fr ,anilinfabrikation put upon the market three fur dyes under the trade name ,ursol1 ,ursol ,d1 giving dark-brown to black shades2 ,ursol ,p1 giving red-brown colors2 and ,ursol ,c1 giving a yellowish-brown shade4 ,pyrogallic acid had been previously used as a hair dye1 and also to a slight extent as a fur dye1 so it was used in conjunction with the ,ursol dyes for shading purposes4 ,the new fur dyes were not dyes in the ordinarily accepted sense of the term4 ,they were really coal-tar intermediates1 substances similar in character to aniline1 and their dyeing property depended on the fact that they could be oxidized either by atmospheric oxygen1 or by means of oxidizing agents1 forming colored insoluble products4 ,when the oxidation of the intermediate was caused to take place on the hair the colored product formed on and in the hair fibre1 and remained fast4 ,the reactions bringing about the conversion of the intermediate to the colored insoluble compound are quite analogous to those of the ,aniline ,black process1 though possibly not so complicated1 with the important difference1 however1 that1 while in the production of ,aniline ,black acid is essential1 in the present instance the oxidation can be carried on in neutral or even alkaline medium4 ,on account of the character of the method used in applying the new fur dyes1 the name ,oxidation ,colors has been given to them4 ,strictly speaking1 ,aniline ,black is also an ,oxidation dye1 but it is usually considered in a class by itself4 ,the methods used at first in the application of the ,ursol dyes to furs followed closely the process as described in the patents4 ,the furs were first killed1 usually by brushing on a lime mixture1 drying1 and then beating out the dust4 ,this operation was repeated1 if necessary4 ,then a solution of the desired dye1 mixed with an equal volume of #c peroxide of hydrogen was brushed on and the fur allowed to lie exposed to the air4 ,the dyeing could also be done by the dip process1 less concentrated solutions being used4 ,by varying the concentration of the solution1 and prolonging or shortening the time of action1 the shades could be varied from very light to very dark1 and by combining two or more of the ,oxidation ,colors1 many different color effects could be produced4 ,soon other fur dyes were developed and put on the market2 for example1 ,ursol ,,db1 giving blue to blue-black shades1 and ,ursol #b;,g1 yielding yellowish tones suitable for mixing with the other colors4 ,ursol ,c was discarded shortly after its introduction4 ,the dyeings obtained with the ,oxidation ,colors seemed to be very fast1 resisting successfully the action of cold or hot water1 or even hot soap solution4 ,moreover1 a dyed hair examined under the microscope appeared to be colored through the epidermis to the medulla1 and no individual particles of dye could be discerned4 ,the new fur dyes had many evident advantages over the coloring matters in general use at the time4 ,the simplicity of the dyeing operations1 the short duration of the process1 the great tinctorial power of the new products1 were facts which strongly recommended themselves to the progressive fur dyer4 ,the cost of the dyes was higher than that of the vegetable dyes1 but this consideration was largely overbalanced by the saving in time and labor in using them4 ,and yet1 the ,ursol dyes found only a comparatively small market4 ,the majority of fur dyers1 always conservative and reluctant to turn from the traditional ways of the industry were skeptical of1 and even hostile towards the new dyes and the new methods of dyeing4 ,in a sense1 this opposition was justifiable4 ,it was not an easy task to relinquish all at once methods which had been successfully applied for generations back1 and with which they were thoroughly experienced1 in favor of processes which were radically different1 and with which they had no experience at all4 ,but some enterprising spirits among the fur dyers undertook to try out the new products and it was not long before the skeptics had good cause for condemning the work and achievements of the chemists as far as fur dyeing was concerned4 ,the new type of dyes did possess some of the advantages claimed for them1 but they also possessed many highly objectionable features1 which had never been manifest with the vegetable dyes4 ,first of all1 the dyeings were not so fast as had at first appeared1 for the color came off the hair when the furs were rubbed1 brushed or beaten4 ,then it was observed that after a short time some of the dyeings changed color1 and at the same time the hair lost its gloss and became brittle4 ,the condition of the leather after dyeing was anything but satisfactory4 ,most serious of all1 however1 was the appearance among the workers in the dyeing establishments1 and also among the furriers who worked with the dyed skins1 of certain pathological conditions which had hitherto been unknown4 ,various skin diseases1 eczemas1 inflammation of the eyes1 asthmatic affections and intestinal irritations were some of the afflictions which were directly attributable to the use of fur dyes of the ,ursol type4 ,medical science was at a loss to know how to treat these ailments1 because their nature was not understood4 ,here indeed1 were obstacles threatening to destroy all the hopes which the discovery of the new class of dyes had aroused1 and to check at the outset the possibility of rational progress in the fur dyeing industry4 ,but the men of science were not content to let the matter drop thus4 ,difficult problems had been solved before1 and surely there must be some way of overcoming the objections and deleterious features of a system of fur dyeing which had so much potential merit4 ,where hindrances sprang up in the path of progress1 it was the duty of the chemist to remove them1 and when difficulties arose1 it was up to him to resolve them1 as far as was humanly possible4 ,so the chemists who had been responsible for the introduction of the ,oxidation ,colors set themselves to the task of eliminating the undesirable or injurious qualities4 ,it was many years before the results of painstaking effort and persistent study cleared up the causes of all the objectionable aspects of the fur dyes1 and suggested means of overcoming them satisfactorily4 ,the work had been directed to the improvement of the dyes and of the methods of dyeing with them4 ,purer intermediates were produced1 and more easily soluble ones1 so that there would be no possibility of ultra-microscopic particles of the dye being deposited on the surface of the hair from the dye solution1 instead of being taken up within the hair fibre4 ,it was this superficial deposition of minute crystals of the dye or of the only partially oxidized intermediate1 on the hair1 crystals so fine as to be invisible in the ordinary high-power microscope1 which caused the color to come off when the furs were brushed or beaten1 giving rise to a dust which was frequently very injurious to the health4 ,then1 mordants were adopted to help fix the dyes1 compounds of copper1 iron1 and chromium being used as formerly with the vegetable dyes1 and the range of shades was also increased thereby4 ,certain of the ,oxidation ,colors had a tendency to sublime off the hair1 so the dyed hair was chemically after-treated in such cases to prevent this4 ,the causes of the pathological aspects of dyeing with the ,oxidation fur dyes were not so readily disposed of4 ,but the adoption of devices to prevent the formation and circulation of dust during the handling of the dye1 the employment of adequate protection against contact with the dye or its solutions1 the use of the most dilute solutions possible in dyeing1 the thorough washing of the dyed skins to remove any excess of the coloring matter1 the prevention of dust formation in the drying of the skins1 and the rigid observance of1 and adherence to hygienic laws1 were all factors in the elimination of the health-impairing phases of dyeing with the ,oxidation ,colors4 ,it was only after all these improvements had been accomplished that the fur dye intermediates began to acquire a degree of popularity among fur dyers1 and strange as it may seem1 there was a more ready market for these dyes in ,america1 than in ,germany where they were manufactured4 ,other manufacturers of coal-tar intermediates also began to produce fur dyes1 and so1 in addition to the ,ursols1 there were the ,nako brand1 the ,furrol brand1 the ,furrein brand1 and one or two others4 ,new dyes were invented1 until the whole range of colors suitable for fur dyeing had been produced4 ,the black dye1 however1 presented some difficulty4 ,a black dye which would rival logwood blacks could not be attained4 ,ursol ,,db in conjunction with ,ursol ,d was being used to produce bluish-blacks1 but the dyeings were not fast1 turning reddish after a time4 ,in #aiji1 a patent was taken out for a dye mixture1 which was made up like the ,,db brand1 but instead of using toluylene diamine with para-phenylene-diamine1 the new dye was made up of a methoxy1 or ethoxy-diamine with para-phenylene-diamine1 and it yielded brilliant bluish-blacks1 which were fast1 and which very nearly approached the logwood black in luster1 intensity1 and bloom4 ,for some purposes1 however1 the production of a black color is still dependent on the use of the logwood dye4 ,when the ,great ,war cut off to a large degree the importation of skins dyed in ,europe1 the ,american fur dyeing industry developed tremendously1 and in a comparatively short time was able satisfactorily to accomplish in the way of dyeing furs1 what had taken foreign dyers a much longer period to attain4 ,it had been previously considered that furs could be dyed properly only by ,european fur dyers1 but the achievements in this direction by ,americans fully dispelled this belief4 ,but the success of the fur dyers in ,america might not have been so marked or rapid1 had it not been for the work of the ,american chemists4 ,the war had also shut off the supply of ,german dyes1 upon which the dyeing industries of ,america had formerly been dependent1 so enterprising chemists in this country undertook to fill the need1 and in a surprisingly short time1 ,american fur dyes1 in every respect the equal of the foreign product were offered to the ,american fur dyers1 and at the present time1 the requirements of the fur dyeing industry in this country are being adequately met by domestic producers4 ,among the brands on the market are the ,rodol1 ,furamine1 ,furol1 and several others4 ,the ,oxidation ,colors are now being offered in a high state of purity1 and easily soluble1 free from any poisonous constituents1 and there is absolutely no reason for the appearance of any pathological conditions among workers on dyed furs1 or users of such furs1 provided the necessary precautions have been taken in the dyeing process4 ,the occurrence of any affection which can be traced to dyed fur1 cannot possibly be due to the dye itself1 but to gross carelessness and negligence in dyeing1 and in any such event1 the dyer responsible should be brought to account4 ,in order to get a better understanding of the nature and action of the ,oxidation ,colors1 a typical one will be studied in some detail4 ,the most important one in this class is para-phenylene-diamine1 usually designated by the letter ,d in all commercial brands of this fur dye1 while its chemical formula is represented as ,c,h7,,nh74 ,when pure it occurs in colorless1 crystalline lumps1 which rapidly turn brown when exposed to the air2 the technical product of commerce is of a dark-brown color4 ,it dissolves readily in hot water when pure1 and also in acids4 ,at one time the hydrochloride was used instead of the free base1 on account of its greater solubility1 but now a base is made which is sufficiently pure to be very soluble in water4 ,there are several methods of preparing para-phenylene-diamine3 first1 by the reduction of amido-azobenzol1 the product obtained in this way always containing a slight amount of aniline1 which reduces the solubility1 and also gives rise to poisonous oxidation products during the dyeing process2 second1 by the reduction of paranitraniline1 the quality and solubility of the product in this case depending on the purity of the starting material2 and third1 by the treatment of para-dichloro-benzol with ammonia under pressure1 the best product being obtained by this method4 ,the crude para-phenylene-diamine1 made by any of the above processes1 is generally distilled in vacuo1 the refined base being obtained as lumps with a crystalline fracture4 ,the first step in the oxidation of the para-phenylene-diamine is the formation of quinone di-imine1 ,,nh3,c,h3,,nh4 ,this is a very unstable compound in the free state1 and even in aqueous solution it decomposes within a comparatively short time1 or combines with itself to form a more stable substance4 ,quinone di-imine has a very sharp1 penetrating odor1 and produces violent local irritations wherever it comes in contact with the mucous membrane4 ,if a small quantity of para-phenylene-diamine is absorbed into the human body1 by breathing the dust1 or otherwise1 the formation of quinone di-imine takes place internally with consequent irritation of the mucous lining throughout the body4 ,the various pathological conditions mentioned before may be ascribed to irritation caused by quinone di-imine4 ,in any dyeing process where there is a possibility of the formation of quinone di-imine1 as is the case with most dyes containing para-phenylene-diamine1 special precautions must be taken by the workers in handling the dye or coming in contact with its solutions1 and no one who is particularly sensitive to irritation should be permitted to work in a place where such dyes are used4 ,the next step in the oxidation of the para-phenylene-diamine is the formation of what is called ,bandrowski's base4 ,three parts of the quinone di-imine combine with themselves1 forming a substance of a brown-black color1 which was formerly regarded as the final oxidation product4 ,the formula of ,bandrowski's base is represented by the following chemical hieroglyphics3 7,,nh74,c,h4,n3,c,h3,n4,c,h7,,nh74 ,further investigation has shown that the oxidation proceeds beyond this stage with the formation of a compound of what is known as the azine type1 which is depicted by the chemist as ,,nh ,,nh 7,,nh74,c,h ,c,h ,c,h4,,nh4 ,,nh ,,nh ,it is by no means certain that this substance is the true coloring matter obtained by the oxidation of para-phenylene-diamine1 for the reactions may continue still farther1 producing even more complicated oxidation products4 ,scientific research and study has not as yet gone beyond this stage4 ,the reactions of the other dyes of the ,oxidation type are quite similar to those of para-phenylene-diamine1 some being simpler1 and others being even more complex4 ,the presence of certain chemical groups in the intermediate1 or the relative position of such groups are factors responsible for the variations in shade4 ,with the various mordants1 the ,oxidation ,colors give different shades1 and a great range of colors can be produced either by combining mordants1 or combining dyes1 or both4 ,the following tables illustrate the shades formed with the customary mordants4 ,,chrome ,,copper ,,iron ,,direct ---------------------------------------- ----------------------------- ,ursol ,d brown black coal black coal black dark brown to brown black ,ursol ,p dull red brown dull dark brown grey brown light brown ,ursol #b;,g yellow brown dull yellow yellow brown dull yellow brown ,ursol ,a 444 444 blue black blue to blue- black ,ursol #d;,g light brown medium brown yellow pure yellow ,ursol #d,r orange brown light yellow red brown orange red brown ,ursol ,grey ,b greenish grey greenish grey mouse grey 444 ,ursol ,grey ,r brownish grey brownish grey reddish grey 444 ---------------------------------------- ----------------------------- ,fur dyes of ,american make being equal in every way to the ,german product1 show the same color reactions with the various mordants4 ,the following table shows the shades produced with the same mordants as above3 ,,chrome ,,copper ,,iron ,,direct ---------------------------------------- ----------------------------- ,rodol ,d brown black coal black coal black brownish black ,rodol ,p red brown dark brown grey brown light brown ,rodol #b;,g yellow brown yellow brown yellow brown dull yellow ,rodol #d;,g light brown light brown reddish brown pure yellow ,rodol ,a 444 blue black 444 blue black ,rodol ,grey ,b greenish grey greenish grey mouse grey 444 ,rodol ,grey ,r greenish grey brownish grey mouse grey 444 ---------------------------------------- ----------------------------- ,all these shades are produced by dyeing in a bath containing a neutral solution of the dye4 ,sometimes the dye comes in the form of a salt of a mineral acid1 like hydrochloric or sulphuric acid1 in which case a sufficient amount of an alkali1 usually ammonia1 is added to liberate the free base4 ,according to the ,cassella ,co41 ,german manufacturers of the ,furrol brand of fur dyes1 the dyeing can also be carried on in slightly alkaline or in slightly acid solution1 a different series of shades being obtained in each instance4 ,ammonia is used to render the bath alkaline1 and formic acid to make it acid4 ,the most customary practise1 however1 is to use neutral solutions of the dyes4 ,for preparing the mordant solutions much smaller quantities of the metallic compounds are used than in the case of the vegetable dyes4 ,with chrome mordants cream of tartar is always employed as an assistant1 and occasionally also with copper and with iron mordants4 ,with copper1 and also with iron mordants no addition is made at all1 or sometimes a small quantity of acetic acid is added4 ,the temperature of the mordant solution is kept about #cj ,c41 and the duration of the mordanting varies from #b-bd hours according to the depth of shade desired4 ,the concentration of the solution may also be varied1 it sometimes being just as well to use a strong mordant solution and less duration of mordanting4 ,chrome may be combined with copper1 and iron may be combined with copper1 but chrome and iron do not go together as mordants4 ,some typical average mordanting formulas are as follows3 ,chrome mordant4 ,bichromate of soda #b4e gms4 ,cream of tartar #a4e gms4 ,water #a liter ,copper mordant4 ,copper sulphate #b gms4 7,acetic acid #ej #b gms47 ,water #a liter ,iron mordant4 ,ferrous sulphate #b gms4 7,acetic acid #ej #b gms47 ,water #a liter or1 ,iron pyrolignite #cj #aj gms4 ,water #a liter ,chrome-copper mordant4 ,bichromate of soda #b gms4 ,copper sulphate #j4be gms4 ,cream of tartar #a4j gms4 ,water #a liter ,copper-iron mordant4 ,copper sulphate #b gms4 ,ferrous sulphate #b gms4 7,acetic acid #ej #b gms47 ,water #a liter ,the killed skins are immersed in the mordanting solution1 and allowed to remain the required length of time4 ,they are then thoroughly rinsed to remove any excess of the mordant1 and are hydro-extracted4 ,under no circumstances should mordanted skins be permitted to dry1 for they would be unfit for use again4 ,the dyebath is next prepared by dissolving the necessary quantity of the dye1 varying from #j4a gm4 to #aj gms4 per liter4 ,then if the solution must be neutralized1 the ammonia is added and the temperature of the bath is brought to #cj-ce ,c4 by the addition of cold water4 ,this temperature is maintained throughout the dyeing operation4 ,to the solution is added the oxidizing agent4 ,ordinary commercial peroxide of hydrogen containing #c by weight is the usual oxidizer1 although perborates have been suggested4 #ae-bj parts of peroxide of hydrogen for every part of dye are added1 and the dye solution brought to the proper dilution4 ,as soon as the dyebath is ready1 the skins are entered1 and worked for a short time to effect even penetration4 ,they are then left in the dyebath for #b-ab hours or longer according to the depth of shade4 ,after being satisfactorily dyed1 the furs are rinsed thoroughly1 hydro-extracted and dried and finished4 ,where the dye is to be applied by the brush to the tips of the hair1 stronger dye solutions are used1 the brushed skins being placed hair together and let lie for about #f hours in order to permit the color to develop1 after which the furs are dried and drum-cleaned4 ,some shades1 particularly black1 have a tendency to rub off slightly4 ,in order to overcome this1 the dyed furs1 after rinsing1 are treated with a cold solution of #a_/b part of copper sulphate per #ajjj parts of water1 for #c-d hours1 then without rinsing1 hydro-extracted and dried4 ,furs which have been tipped are brushed with a #a-b solution of copper sulphate and dried4 ,care must be taken in this after-treatment1 for the use of too strong a solution of copper sulphate1 or too prolonged action of such a solution will materially alter the shade of the dyed fur4 ,a few typical formulas will serve to illustrate the general methods of employing the ,oxidation ,colors3 ,brown ,sable ,imitation on ,unsheared ,rabbit ,the skins are killed with soda1 soured1 and washed1 then mordanted with ,bichromate of soda #b grams ,copper sulphate 4#be grams ,cream of tartar #a gram ,water #a liter for #bd hours4 ,then washed1 and dyed for #bd hours with ,fur ,brown #b;,g#c #c grams ,hydrogen peroxide #de grams ,water #a liter ,wash and dry the skins1 then brush the tips with ,fur ,brown ,d#c #bj grams ,hydrogen peroxide #djj grams ,water #a liter #c ,inasmuch as most manufacturers use the same letters to designate the various dyes1 any equivalent brand of fur dye may be used in place of those here mentioned4 ,black on ,sheared ,muskrat ,the skins are killed with soda1 soured1 and washed1 then chrome mordanted for #f hours4 ,then they are dyed for #f hours with ,rodol ,p #a4e grams ,pyrogallic acid 4#g grams ,ammonia #b4j grams ,hydrogen peroxide #de grams ,water #a liter ,the dyed skins are washed and dried1 then tipped with ,rodol ,d #bj grams ,rodol ,,db #b grams ,hydrogen peroxide #dej grams ,water #a liter ,brown on ,thibet ,sheep ,skin ,the killed skins are mordanted for #f hours with a chrome mordant1 then dyed for #f hours with ,ursol ,p #a gram ,pyrogallic acid #a gram ,ammonia #b grams ,hydrogen peroxide #dj grams ,water #a liter ,it is also possible to combine dyeings with the ,oxidation ,colors with ,vegetable dyeings1 or with ,aniline ,black4 ,for example1 if it be desired to produce an imitation skunk on a raccoon1 and an exceptionally fast and intense and lustrous black on the tips of the hair1 the skins are dyed in the bath with the ,oxidation dyes1 and the tips of the hair are brushed with a mixture such as described under ,vegetable ,colors for the production of ,french seal1 as follows3 ,imitation ,skunk on ,raccoon ,the skins are killed with caustic soda1 soured and washed1 then mordanted with an iron-copper mordant as described1 and then dyed with ,fur ,grey ,r #c grams ,ammonia #b grams ,peroxide of hydrogen #de grams ,water #a liter ,after washing and drying1 the dyed skins are brushed over with a mixture such as used for dyeing ,french seal with ,vegetable ,colors4 ,in a similar manner1 the ,oxidation ,colors may be used to give a base color to furs dyed by the ,aniline ,black process4 ,it is apparent from these few illustrations that a great variety of shades can be produced1 and the dyeing of imitations of the better class of furs on cheaper skins is a comparatively simple matter1 after an understanding of the nature of the dyes has been obtained1 and a certain amount of skill acquired in working with these dyes4 ,,chapter ,,xvi ,,fur ,,dyeing ,,coal ,,tar ,,dyes ,in addition to the ,aniline ,blacks and the ,oxidation ,colors already discussed there are certain of the synthetic coal tar dyes such as are generally used in the dyeing of textiles1 which can also be applied on furs4 ,there are several classes of these dyes1 varying somewhat in their nature1 and consequently in their manner of application2 in the main they produce bright shades1 such as are but seldom used on furs1 yet which may occasionally serve for the production of novel effects4 ,basic1 acid and chrome colors are the types which can be employed4 ,basic colors possess great fullness and tinctorial strength1 but have a tendency to rub off1 and the tips of the hair take a darker shade with these dyes than the rest of the hair4 ,the addition of acetic acid and ,glauber's salt to the dyebath will result in a more uniform dyeing4 ,on account of the comparatively poor fastness to rubbing and washing1 basic dyes are used only for dyeing furs which are intended for cheap carpet rugs1 such as sheep and goat4 ,they may also find use in the production of light fancy shades on other white furs4 ,the procedure is usually as follows3 ,the furs are killed in the customary manner with soap and soda or ammonia1 or if this is insufficient1 with milk of lime4 ,a soap-bath is then prepared containing #b4e-f grams of olive-oil soap per liter of water4 ,the temperature of the bath is brought to #dj ,c4 ,to this is added the solution of the dyestuffs1 prepared by mixing the required color or colors with a little acetic acid to a paste1 and then pouring boiling water on the mixture until dissolved4 ,undissolved particles or foreign matter are removed by passing this solution through a cotton cloth or sieve1 and the clear solution then mixed with the soap-bath4 ,the well-washed skins are then entered into the dyebath and immersed for about half an hour1 or until the desired depth of shade is obtained4 ,they are then removed1 pressed or hydro-extracted and dried4 ,for the production of light shades1 the following dyes may be used3 ,for cream1 light sulphur-yellow1 maize1 salmon1 etc4 ,combinations of ,thioflavine ,rhodamine ,b ,irisamine ,g ,for greenish-yellows ,combinations of ,thioflavine ,victoria ,blue ,b ,for light pink ,rhodamine ,b ,irisamine ,rose ,bengal ,extra ,n ,for purple ,methyl ,violet #c;,b-#f;,b ,crystal ,violet ,for sky-blue ,victoria ,blue ,b ,for white ,victoria ,blue ,b 7,milk-white7 ,methyl ,violet #c;,b-#f;,b ,crystal ,violet 7,ivory-white7 ,to produce very delicate shades1 the moist dyed skins are subjected to a sulphur bleach overnight1 to lighten the color1 then rinsed1 and dried4 ,full1 brilliant shades may be obtained by dyeing in a bath of #dj ,c41 acidulated with #b-c grams of acetic acid per liter of solution1 the following dyestuffs being suitable3 ,for yellow to orange ,thioflavine ,paraphosphine ,rhodamine ,safranine ,new ,magenta ,o ,for pink ,rhodamine ,b ,rose ,bengal ,extra ,n ,for light red ,safranines ,for bordeaux and red ,magenta ,new ,magenta ,russian ,red ,cerise ,for violet ,methyl ,violet #f;,b-#d,r ,crystal ,violet #e;,b ,for blue ,victoria ,blue ,b ,methylene ,blue ,,bb ,new ,methylene ,blue ,n ,for green ,malachite ,green ,crystals ,brilliant ,green ,crystals1 or combinations of ,thioflavine ,diamond ,phosphine ,victoria ,blue ,b ,for brown ,chrysoidines ,bismarck ,browns ,in dyeing skins with harder hair than that of sheep or goat1 mere killing is insufficient to render the hair capable of taking up the dye4 ,the skins are therefore immersed before dyeing1 in a cold1 weak solution of chloride of lime1 the affinity of the hair for the dye being thereby greatly increased4 ,acid dyes are employed when a greater fastness is required than can be obtained with the basic colors4 ,sulphuric acid in a quantity equal to half the weight of the dyestuffs used1 together with four times that quantity of ,glauber's salt is added to the dyebath4 ,formic acid may be used in place of the sulphuric acid1 very good results being obtained4 ,the skins are immersed in the dyebath1 and worked until thoroughly soaked with the dye liquor1 and then allowed to remain until the proper depth of shade is attained1 or overnight4 ,the temperature of the solution is about #dj ,c41 and only very light shades can be produced in this manner4 ,in #aijj and again in #aiad1 the ,cassella ,co41 a large ,german manufacturer of dyestuffs1 obtained patents for processes enabling the dyeing of furs in hot solution with the acid dyes4 ,the method required that the skins be chrome-tanned in order to render them resistant to the action of hot solutions1 the addition of a small amount of formaldehyde to the chrome solution increasing this effect4 ,the skins are then treated with a solution of chloride of lime in order to increase the affinity of the hair for the dyestuffs4 ,the method as it is now practised is as follows3 ,the skins which have been cleaned and washed are chrome tanned by the method as described in the chapter on ,tanning ,methods1 #fj grams of formaldehyde being added to every #aj liters of the chrome solution4 ,after proper tanning the skins are rinsed1 and while still moist they are subjected to a treatment with chloride of lime4 ,they are first immersed for #ae minutes in a cold bath containing #abj grams of hydrochloric acid #cb-cf ,twaddell per #aj liters of water1 then without rinsing1 they are entered into a bath made up by adding gradually in four portions the clear solution of #b-d grams of the chloride of lime per #aj liters of water4 ,after working for an hour1 the skins are removed and entered again into the acid solution1 in which they are worked for another #ae minutes4 ,in order to neutralize and remove the last traces of the chloride of lime from the furs1 they are rinsed in a luke-warm bath containing #a-b grams of sodium thiosulphate1 or hyposulphite of soda1 in #aj liters of water4 ,the skins are then rinsed again1 and hydro-extracted1 or pressed1 and are ready for dyeing4 ,the dyebath is prepared with the required quantity of dye1 to which is added #aj-bj ,glauber's salt and #b-e acetic acid 7both calculated on the weight of the skins74 ,the skins are entered at #bj ,c41 then after three-quarters of an hour to #dj ,c41 and then after another hour slowly to #ej-ee ,c4 ,for blacks1 the temperature is raised as high as #fe ,c4 ,after dyeing the skins are treated with a solution containing per #aj liters #ij-abj grams of olive-oil soap #ab-be grams olive oil #ab grams ammonia for #ae minutes1 then hydro-extracted and dried1 without further rinsing4 ,for this method of dyeing1 the following dyes may be used3 ,for yellow and orange ,fast ,yellow ,s ,acid ,yellows ,naphthol ,yellow ,s ,tropaeoline ,orange ,,gg1 ,r1 ,,ii1 ,,iv ,for reds ,acid ,reds ,lanafuchsine ,azo ,orseille ,for violet ,azo ,wool ,violet ,acid ,violets ,for blue ,cyanole ,,ff ,azo ,wool ,blue ,naphthol ,blue ,r ,formyl ,blue ,b ,for green ,naphthol ,green ,b ,fast ,acid ,green ,cyanole ,green ,for brown1 combinations of ,fast ,yellow ,s ,acid ,yellows ,tropaeoline ,,dd ,orange ,,gg ,lanafuchsine ,indigo ,blue ,n ,cyanole ,b ,fast ,acid ,green ,,bn ,for black ,naphthylamine ,blacks ,naphthol ,blacks ,naphthol ,blue-black ,for grey ,silver ,grey ,n ,dyed with the addition of #a_/b-a of alum ,the chrome colors are dyed on furs when very fast shades are desired1 all the fancy colors being produced in this manner1 but for black1 only the acid dyes are suitable4 ,the preparation of the skin is exactly the same as for the acid colors1 except that the treatment with chloride of lime may be omitted1 although for very full shades it is desirable4 ,the dyeing is carried out as follows3 ,the dyebath is prepared with the requisite amount of the desired dyestuff1 which is previously dissolved1 and to this is added a solution of sodium bichromate1 the amount of this substance being half the weight of the dye4 ,the solution is heated and the skins entered and dyed for #a-b hours at #gj-hj ,c4 ,then the dyebath is exhausted by the addition of #a_/c acetic acid1 the skins being worked for another half hour1 then rinsed1 hydro-extracted and dried4 ,any of the one-bath chrome1 or after-chrome colors may be used for this method4 ,recently methods have been patented for the dyeing of furs by means of the vat colors4 ,vat dyes are among the fastest coloring matters ever produced1 and their application on furs would be a great advantage1 if suitable shades could be obtained4 ,the general process for dyeing with vat colors1 consists in reducing the dye1 which is usually very insoluble1 into a soluble 8leuco0 compound1 by means of hydrosulphites in the presence of alkalies4 ,the leuco compound is not a dye itself1 but when the fibre absorbs it1 and is then exposed to the air1 the leuco compound is reoxidized to its original insoluble form1 which remains fast and permanent4 ,the use of strong alkalies in vat dyeing has hitherto been a great obstacle in the use of these dyestuffs1 but in #aiag1 the ,farbwerke ,hoechst1 a large ,german dye works1 patented a process as follows3 8,a process for dyeing furs with vat colors4 ,the dyeing is done in solutions of the vat dyes 7after the addition of gelatine or some other protective colloid71 which are rendered neutral or only slightly alkaline with ammonia1 by neutralizing the caustic soda of the solution of the leuco compound of the vat dyes by the addition of ammonium salts1 or suitable acids4 ,the dyeings thus obtained are uniform and fast1 the leather is dyed to only a slight degree1 and shows no deleterious effects of the dyebath on the tannage40 ,as a practical application of this process1 another patent was taken out by the same company1 also in #aiag1 as follows3 8,a process for producing fast blacks on furs1 consisting of dyeing a ground color with appropriate vat dyes in a hydrosulphite vat1 and after oxidation in air1 topping with an ,aniline or ,diphenyl black4 ,the dyeings obtained by the combination of vat dyes which are fast to oxidizing agents1 with an oxidation black1 have an appearance matching that of logwood black in beauty2 and with a dark-blue to blue-black under-color1 and a full1 deep black top color1 cannot be distinguished from logwood4 ,these dyeings also have the advantage of being faster to light than logwood or other blacks40 ,while these processes undoubtedly have many meritorious qualities which make them interesting1 they do not seem as yet1 to have attained any great practical application4 ,however1 it is a field of fur dyeing which is worth while developing1 and with certain necessary improvements in these processes1 the vat dyes may yet supersede partially some of the other methods of dyeing furs4 ,,chapter ,,xvii ,,bleaching ,,of ,,furs ,bleaching is for the purpose of lightening the color of furs1 and is most generally applied to white-haired skins such as white fox1 ermine1 and occasionally white lambs of all kinds1 and white bears4 ,among such furs1 pelts of a naturally pure white tone are relatively scarce1 while in the majority of cases the color ranges from a pale creamy white to a decidedly yellowish shade4 ,colors which vary from the pure white detract considerably from the attractiveness and consequent value of the fur1 and indeed1 some pelts are so far off shade that they can only be used when dyed a darker color4 ,most white skins which are but slightly inferior in color can be brought to a pure white by bleaching1 and they can then be used natural4 ,some pelts1 on the other hand1 are particularly resistant to the action of bleaching agents and cannot be sufficiently decolorized to render them suitable for use natural1 so these are also dyed4 ,for the production of certain delicate or fancy dyed shades on white furs1 it is often necessary to bleach the skins in order to be able to obtain pure tones4 ,such instances are not very common1 however4 ,occasionally dark furs1 such as beaver1 are bleached on the tips of the hair1 a golden shade being obtained thereby1 which at one time was quite popular1 but recently such effects have not been in vogue4 ,in the bleaching of furs1 two steps may be distinguished1 first degreasing1 and second1 bleaching proper4 ,in the preliminary operations of fur dressing1 the furs are treated with soap or weak alkalies to cleanse them and to remove excess oil from the hair4 ,during the various processes and manipulations1 the hair1 especially on white skins1 may become soiled or somewhat greasy again1 so it is advisable to repeat the cleaning process4 ,this should in every case be as light as possible1 using a weak solution of soap for the softer and cleaner pelts1 or dilute solutions of ammonium carbonate or soda ash for the more greasy-haired skins4 ,the skins are then thoroughly rinsed to remove all traces of the degreasing material4 ,this step is very essential in order to obtain uniform bleaching4 ,broadly speaking1 there are two general methods which can be used in bleaching furs1 one involving the use of what are known as reducing agents1 and the other employing oxidizing substances4 ,among reducing agents which can be used for bleaching furs are sulphurous acid1 and its salts such as sodium bisulphite and sodium sulphite2 hydrosulphites1 and derivatives4 #a4 ,sulphurous acid4--,when sulphur is burned1 sulphur dioxide gas is formed4 ,in the presence of moisture1 or when dissolved in water1 this gas forms sulphurous acid1 which is one of the most commonly used bleaching chemicals for all sorts of materials1 and is very effective for decolorizing furs4 ,the procedure usually followed is to hang up the moistened skins on wooden rods in a more or less cubical chamber made of stone or brick1 and lined with wood or lead4 ,no other metals may be used1 because they are quickly corroded by the sulphurous acid4 ,the requisite quantity of sulphur is placed in a pot in the bleaching chamber1 and then ignited1 after which the doors are shut tight4 ,the fumes of the burning sulphur in contact with the moist hair readily exert their bleaching action on the furs1 and the operation is allowed to proceed for six or eight hours1 or overnight4 ,then by means of fans or other devices1 the air filled with sulphur dioxide gas is withdrawn from the chamber1 and replaced by fresh air4 ,the door is opened1 the skins removed1 exposed to the air for a time1 then rinsed1 and finally dried and finished4 ,sometimes one operation is not enough to sufficiently bleach the hair1 so the process is repeated4 ,sulphur dioxide gas can now be obtained compressed in cylinders1 which are more convenient to handle than burning sulphur4 ,the flow of gas which is introduced into the bleaching chamber by means of a nozzle attached to the cylinder1 can be regulated1 and the bleaching thus retarded or accelerated4 #b4 ,sodium bisulphite and sodium sulphite4--,these salts of sulphurous acid are effective in their bleaching action only when in solution in the presence of acids4 ,the acids liberate sulphurous acid from the salts1 so this method is virtually the same as #a4 ,instead of using the salts of sulphurous acid1 sulphur dioxide may be dissolved in water1 and the solution used for bleaching by immersing the furs in it4 ,this procedure1 while consuming somewhat less time than the chamber process1 is more likely to affect the leather1 which would have to be retanned4 ,the principle is the same as that involved in method #a4 #c4 ,hydrosulphites and derivatives4--,the bleaching agent can be prepared by adding zinc dust to commercial bisulphite of soda dissolved in about four times its weight of water until no more reaction is evident4 ,milk of lime is then added to precipitate the zinc1 and the clear supernatant liquid of #a4e-e ,tw4 is used for bleaching4 ,the skins are immersed for #ab-bd hours1 taken out1 washed and finished4 ,instead of preparing the hydrosulphite1 the commercial products may be used with greater convenience1 a solution containing #a-d of the hydrosulphite powder being used1 and the skins treated in this until satisfactorily bleached4 ,the bleaching action of sulphurous acid and hydrosulphite is supposed to be due to the reduction of the coloring matter of the hair to a colorless compound2 or possibly to the formation of a colorless compound of the bleaching material with the pigment4 ,the former seems the more probable explanation1 because the change is not a permanent one1 the original natural color returning after a long exposure of the bleached fur to air and light4 ,however1 the results are sufficiently enduring to satisfy the requirements of the trade in the class of furs on which these methods of bleaching are used4 ,bleaching chemicals with an oxidizing action generally used for decolorizing furs are hydrogen peroxide and peroxides2 occasionally hypochlorites and permanganates are also used4 #a4 ,hydrogen peroxide4--,hydrogen peroxide is usually employed for bleaching in the form of its #c solution1 to which is added about #bj cubic centimeters of ammonia per liter4 ,the ammonia serves partially to neutralize the acid which commercial peroxide generally contains1 and also to facilitate the bleaching action4 ,the thoroughly degreased skins are immersed in the solution until the hair is completely wetted by it1 are then removed1 and evenly pressed or hydro-extracted1 after which the pelts are hung up to dry in the air4 ,as the hair becomes drier1 the concentration of the peroxide becomes greater1 and consequently the bleaching action is stronger4 ,where there is a likelihood of the leather being affected by the bleaching solution1 the ammoniacal peroxide may be applied to the hair with a fine sponge or brush until sufficiently wetted1 and then hanging the skins up to dry4 ,repetition of the process is sometimes necessary to obtain pure white1 but the results are always excellent4 #b4 ,peroxides4--,the most important of these is sodium peroxide1 which comes on the market as a yellowish-white powder1 which must be kept dry1 and away from any inflammable material1 as fires have been caused by the contact of the peroxide with such substances4 ,when dissolved in water1 it is equivalent to a strongly alkaline solution of peroxide of hydrogen4 ,na,o #b;,h,o ,h,o #b,na,o,h sodium water peroxide caustic peroxide of soda hydrogen ,when dissolved in acid1 the alkali is neutralized1 and a neutral solution of peroxide of hydrogen and a salt is obtained1 and this method is used to obtain peroxide of hydrogen cheaply4 ,na,o ,h,,so ,h,o ,na,,so sulfuric sodium acid sulphate #c parts of sodium peroxide are slowly dissolved in a cold #a solution of #d parts of sulphuric acid1 stirring during the addition1 and making the resulting solution neutral to litmus paper1 acid or more sodium peroxide being added as needed4 ,there is then added #c-f parts of a solution of silicate of soda of #ij ,tw4 ,the skins are immersed until properly bleached1 taken out1 passed through a weak acid solution1 then washed and finished4 ,this method generally requires the leather to be retanned after bleaching4 ,another process1 which involves the use of peroxides1 but which is not commonly practised1 consists in rubbing the hair with a pasty mixture of equal parts of water1 barium dioxide1 and silicate of soda1 hanging up the skins to dry1 and then beating and brushing the hair4 #c4 ,permanganates4--,the only member of this group that finds practical application for bleaching purposes is potassium permanganate4 ,the skins are immersed in a #j4a solution of the crystals of potassium permanganate1 until the hair acquires a deep brown color4 ,they are then removed1 rinsed1 and entered into a second bath containing sulphurous acid in solution1 prepared by acidifying a solution of sodium bisulphite4 ,the skins are then worked in this until fully bleached4 ,it is the permanganate which does the bleaching1 the sulphurous acid being for the purpose of dissolving the brown compound of manganese formed on the hair4 #d4 ,hypochlorites4--,chloride of lime and sodium hypochlorite1 which is prepared from the former1 are the chief chemicals of this type used for bleaching4 ,the skins are entered into a weak solution of the hypochlorite1 and left until the hair is decolorized2 then after removing1 they are passed through a dilute acid1 and subsequently through a weak solution of sodium thiosulphate in order to remove all traces of the hypochlorite4 ,this method causes the hair to acquire a harsh feel1 and the yellow color is never entirely eliminated4 ,the hair1 however1 possesses a great affinity for certain types of dyestuffs1 and it is only when these particular classes of dyes are to be applied to the furs1 that the hypochlorite bleach is used4 7,see dyeing with ,acid colors74 ,the various oxidation methods of bleaching are supposed to change the coloring matter of the hair into an entirely different and colorless compound which cannot return to its original form4 ,the bleach is therefore permanent4 ,in common practise1 the sulphurous acid1 and the peroxide of hydrogen methods are the two chiefly employed in bleaching processes4 ,sulphurous acid is used to bleach the cheaper kinds of furs1 while peroxide of hydrogen is applied to the finer furs4 ,whichever process is used1 it is customary to give the bleached skins a subsequent 8blueing10 by passing them through a very weak solution of a blue or violet dye1 such as indigo-carmine1 crystal violet1 alkali blue or ultramarine4 ,the furs are then dried and finished off as usual4 ,in drum cleaning white furs1 gypsum or white sand1 or sometimes even talc are used with the sawdust1 or occasionally alone without the sawdust4 ,,bibliography ,allen 8,commercial ,organic ,analysis0 ,armour1 ,b4 ,r4 8,fur ,dressing and ,dyeing0 #aiai ---- ,color ,trade ,journal1 ,vol4 #a1 p4 #ea-ec ---- ,jour4 ,amer4 ,leather ,chemists' ,assn41 ,vol4 #ac1 p4 #fc-fi4 ,belden1 ,a4 ,l4 8,fur ,trade in ,america0 #aiag ,beltzer1 ,f4 ,j4 ,g4 8,industrie des ,poils et ,fourrures1 etc40 #aiab ---- ,revue ,generale des ,matieres ,colorantes1 ,vol4 #ab1 #aijh ,bennett1 ,h4 ,g4 8,manufacture of ,leather0 #aiaj ,bertram1 ,p4 ,deutsche ,frber-,zeitung #ahie-if ,heft #ag1 p4 #bff ,bird1 ,f4 ,j4 8,american ,practical ,dyers' ,companion0 p4 #bda-bde ,boerner1 ,h4 ,kunststoffe1 #aiab p4 #bbc ,brevoort1 ,h4 ,l4 8,fur ,fibres as shown in the ,microscope0 #ahhf ,bucher1 ,b4 8,geschichte der technischen ,knste0 #ahge-ahic ,cubaeus1 ,p4 8,das ,ganze der ,krschnerei0 #aiab ,davis1 ,c4 ,t4 8,manufacture of ,leather0 ,erdmann1 ,e4 ,deutsche ,frber-,zeitung #ahid-ie ,heft #ba1 p4 #ccg ---- ,zeitschrift fr angewandte ,chemie1 #ahie1 ,heft #ad ---- ,zeitschrift fr angewandte ,chemie1 ,heft #ce1 #aije ---- ,berichte1 #aijd1 #cg1 p4 #bggf1 #bijf ,farrell1 ,f4 ,j4 8,dyeing and ,cleaning0 #aiab ,fleming1 ,l4 8,practical ,tanning0 #aiaf ,fougerat1 ,l4 8,la ,pelleterie dans l'antiquit1 la prhistoire1 etc40 ,gardner1 ,w4 ,m4 8,wool ,dyeing0 #ahif ,grandmougin1 ,e4 ,zeitschrift fr ,farben-,industrie1 #aijf1 #e1 p4 #ada ,gruene1 ,e4 ,deutsche ,frber-,zeitung1 #ahie-if ,heft #ac1 p4 #aig ,halle 8,werksttte der heutigen ,knste10 #agfb1 ,vol4 #b1 p4 #cag ,hartwig1 ,o4 ,l4 8,sprengler's ,knste und ,handwerke10 #aghb ,hausman1 ,l4 ,a4 ,scientific ,monthly1 ,jan4 #aibj2 ,march1 #aiba ---- ,natural ,history1 ,vol4 #bj1 #d1 #aibj ---- ,american ,journal of ,anatomy1 ,sept4 #aibj ---- ,american ,naturalist1 ,nov4-,dec4 #aibj ,hayes1 ,a4 ,h4 ,national ,cleaner and ,dyer1 ,nov4 #aibj1 p4 #ee-eg ,jacobson1 8,schauplatz der ,zeugmanufacturen0 p4 #dic ,jones1 ,j4 ,w4 8,fur ,farming in ,canada0 #aiac ,knecht1 ,rawson ,loewenthal 8,manual of ,dyeing0 #aiaf ,kobert1 ,r4 8,beitrage zur ,geschichte des ,gerbens und der ,adstringentien0 #aiag ,koenig1 ,f4 ,zeitschrift fr angewandte ,chemie1 #aiad1 ,vol4 #a1 p4 #ebi ,lamb1 ,j4 ,w4 ,jour4 ,soc4 ,dyers ,colourists ,dec4 #aije1 p4 #cbc ,lamb1 ,m4 ,c4 8,dressing of ,leather0 #aijh ---- ,jour4 ,soc4 ,dyers ,colourists #aiac1 #bi1 p4 #afj-afe ,larish ,schmid 8,das ,kuerschner ,handwerk0 #a-c ,laut1 ,a4 ,c4 8,the ,fur ,trade of ,america0 #aiba ,lightfoot1 ,j4 8,the ,chemical ,history ,progress of ,aniline ,black0 #ahga ,mairet1 ,e4 ,m4 8,a ,book on ,vegetable ,dyes0 #aiaf ,martin1 ,g4 8,industrial ,organic ,chemistry0 ,matthews1 ,j4 ,m4 8,application of ,dyestuffs0 #aibj ,mayer1 ,a4 8,die ,frberei in der ,werksttte des ,krschners0 ,mierzinski1 ,s4 8,die ,gerb und ,farbstoffextrakte0 ,noelting ,lehne 8,anilin-,schwarz0 #aijd ,perkins ,everest 8,natural ,organic ,coloring ,matters0 #aiah ,petersen1 ,m4 8,the ,fur ,traders ,fur-,bearing ,animals0 #aibj ,poland1 ,h4 8,fur-,bearing ,animals in ,nature and ,commerce0 ,proctor1 ,h4 8,leather ,industries ,laboratory ,book0 ---- 8,tanning0 ---- 8,making of ,leather0 ,schlottauer1 ,e4 ,deutsche ,farber-,zeitung #aiaa1 ,heft #bj1 p4 #cig ---- ,deutscher ,frber-,kalender #aiaa1 p4 #fe ---- ,leipziger ,frber-,zeitung #aiji1 p4 #dda ,schmidt1 ,c4 ,h4 8,handbuch der ,weissgerberei0 ,setlik1 ,b4 ,deutsche ,frber-,zeitung #aija1 p4 #bac ,smith1 ,r4 ,w4 ,color ,trade ,journal ,vol4 #c1 ,sept4 #aiah1 p4 #cjd-caj ---- ,textile ,recorder1 ,vol4 #cf1 p4 #bib-bic1 ,dec4 #aiah ---- ,revue ,generale des ,matieres ,colorantes1 ,vol4 #bc1 p4 #cb-cf ,stevenson1 ,c4 ,h4 8,u4 ,s4 ,fish ,commission ,report #aijb-aijc01 ,bulletin ,no4 #ecg ,stickelberger1 ,e4 8,geschichte der ,gerberei0 #aiae ,strasser 8,chemische ,frberei der ,rauchwaren0 #ahgi ,ullmann 8,enzyklopedie der technischen ,chemie0 ,villon1 ,a4 ,m4 8,trait pratique de la fabrication des cuirs1 etc40 #aijj ,werner1 ,h4 8,die ,krschnerkunst0 #aiad ---- 8,das ,frben der ,rauchwaren0 #aiad ,whittaker1 ,c4 ,m4 8,dyeing with ,coal ,tar ,dyes0 #aiai ,wiener1 ,f4 8,weissgerberei0 #ahgg ,witt-,lehman 8,chemische ,technologie der ,gespinst-,fasern0 #aiaj ,zeidler1 ,h4 8,die moderne ,lederfabrikation0 #aiad ,,index ,acetate1 aluminum1 #aah ---- chromium1 #abj ---- copper1 #abj ---- ferrous1 #aai ---- lead1 #abf ,acetic acid1 #aab ,acid dyes1 #agd ,acids1 action of1 on hair1 #bi ---- ---- on skin1 #bf ,after-treatment with copper1 #afh ,alaska fox imitations1 #adc ,alkaline aluminum mordants1 #abb ---- chromium mordants1 #abc ---- iron mordants1 #abc ,alum1 #cb1 #ec1 #aah ---- chrome1 #eg ---- -chrome tans1 #fd ---- tans1 #ed1 #ef ,aluminum acetate1 #aah ---- mordants1 #aah ---- sulphate1 #ec1 #aah ,ammonia1 #aaj ,ammonium sulphide1 #abf ,aniline black1 #add ---- ---- by dip process1 #aed ---- ---- chemistry1 #ade ---- ---- ,green's process for1 #aeb ---- ---- nature of1 #add ---- ---- ,one-bath1 #adi ---- ---- ,oxidation1 #aej ---- ---- processes1 #adi ---- ---- ungreenable1 #adh ,aniline oil1 #ade ,astrachan #e1 #g1 #ab ,bacteria1 #ea ,badger1 #g ,ball-drum1 #fb ,bandrowski's base1 #afd ,basic dyes1 #aga ,beam1 #ch ,beaming1 #ch ,bear1 black1 #e1 #g ---- brown1 #e1 #h ---- white1 #h ---- ---- bleaching of1 #agi ,beating furs1 #gi ,beaver1 #e1 #h1 #be1 #hc1 #id ,beechwood ashes1 #ajh ,bichromate of soda1 #aba1 #adg ,black1 aniline1 #add ---- ---- by ,green's process1 #aeb ---- ---- chemistry of1 #ade ---- ---- nature of1 #add ---- ---- ,one-bath1 #adi ---- ---- ,oxidation1 #aej ---- ---- ungreenable1 #adh ,black1 diphenyl1 #aeb ---- logwood1 #aci ---- on ,chinese goats1 #ada ---- on lambs1 #ada ---- on raccoon1 #acj ---- on skunk1 #acj ---- on wolf1 #acj ,bleaching of furs1 #agi ,blending1 #ia1 #ajd ,blue-grey on white furs1 #adb ,blueing1 #ahd ,blue salt1 #abj ---- vitriol1 #aai ,borax1 #ci1 #eh ,brasilein1 #ace ,brasilin1 #ace ,brazilwood1 #ace ,bright shades on furs1 #aga ,broadtail1 #h1 #ab ---- dyeing of1 #aci ,brown on ,thibet sheep1 #afi ---- with natural dyes1 #adb ,brush process1 #ih ,brushes used in dyeing1 #ajj ,butter1 #fj1 #fc ,cage1 #hj ,cageing1 #hj ,campeachy wood1 #acc ,caracul1 #h1 #ab ---- dressing of1 #ec ,caracul1 dyeing of1 #adj ,carnivorous animals1 furs of1 #cg ,cased skins1 #cf ,castor oil1 #fj1 #fc ,cat1 civet1 #e1 #h ---- house1 #h ,caustic soda1 #dd1 #aaj1 #aac ,centrifugal machine1 #dj ,chamber drying1 #gc ,chamois dressing1 #ca ---- tan1 #di1 #eh1 #fa ,characteristics of tans1 #fe ,chestnut extract1 #acc ,chinchilla1 #e1 #f1 #h1 #id ---- blending of1 #ia1 #ajd ,chinchillone1 #i ,china goat1 black on1 #ada ,chlorates1 #adg ,chloride of lime1 #agd ---- ---- bleach1 #ahd ,chrome acetate1 #abj ---- alum1 #eg1 #abj ---- colors1 #agf ---- -copper mordant1 #afg ---- -formaldehyde tan1 #fd ---- tans1 #eg1 #agd ,chromium mordants1 #abj1 #aff ---- ---- alkaline1 #abc ---- salts in tanning1 #ec ,cleaning pelts1 #dj ,coal tar colors1 #aga ,cocoanut oil1 #fj ,cod-liver oil1 #fj ,collagen1 #be ,colloidal solutions1 #dh ,combination tans1 #di1 #fd ,conveying dyed skins1 #ajd ,conveyor drying1 #gc ,copper acetate1 #aai ---- mordants1 #aai1 #aff ---- salts1 #aji ---- ---- after-treatment with1 #afh ---- sulphate1 #aai ,copperas1 #aai ,copper-iron mordant1 #afg ,coriin1 #ba ,corium1 #ba ,cortex1 #bc ,cottonseed oil1 #fj1 #fc ,cuba wood1 #acd ,cutch1 gambier1 #fe1 #ace ,cuticle1 #bc ,davy1 ,sir ,humphrey1 #dg ,degreasing furs1 #agi ,diphenyl black1 #aeb ,dip process1 #ih ,dressing of lambs1 #eb ---- ---- rabbits1 #ed ---- ---- moles1 #ed ,drum1 #hj ,drum-cleaning1 #aje ,drumming1 #gf ,drying-oils1 #fj ,drying skins1 #ga ,durability of furs1 #e ,dyeing furs at higher temperatures1 #agd ,dyeing of imitations1 #ic ---- ---- novelty shades1 #ib ---- with aniline black1 #add ---- ---- coal tar colors1 #aga ---- ---- mineral colors1 #abe ---- ---- oxidation colors1 #aee ---- ---- vegetable colors1 #abh ,egg-yolk1 #fc ,emeraldine1 #ade ,enzymes1 #ea ,epidermis1 #ba ,erdmann1 #aee ,ermine1 #e1 #i ---- bleaching of1 #agi ,fahrion1 #dh ,fat-glands1 #ba ,fats1 animal1 #ei ,fermentation1 #ea ,ferrous acetate1 #aai ,ferrous sulphate1 #aai ,finishing dyed furs1 #ajd ,fisher1 #i ,fitch1 #i1 #id ,flat skins1 #cf ,fleshing1 #da ---- knife1 #ch1 #db ---- machines1 #db ,flesh side1 #bb1 #cg ,formaldehyde1 #fc ---- -chrome tan1 #fd ---- tans1 #di1 #fc ,formic acid1 #dd1 #ej ---- ---- as soaking agent1 #ci ,fox1 black on1 #adj ---- blue1 #i ---- cross1 #d1 #aj ---- grey1 #aj ---- kit1 #aj ---- red1 #d1 #e1 #aj ---- ---- dyed imitation silver fox1 #acg ---- silver1 #d1 #aj ---- ---- imitations1 #acg1 #adc ---- white1 #aa1 #id ---- ---- bleaching of1 #agi ,french seal dye1 #ach1 #add ,furamine dyes1 #afb ,fur beating machine1 #hj ,fur dressing1 #cj ,fur dyeing1 #ia ---- ---- difficulties of1 #ie ---- ---- with aniline black1 #add ---- ---- with coal tar colors1 #aga ---- ---- with mineral colors1 #abe ---- ---- with oxidation 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seal1 #add ,hydro-extraction1 #dj ,hydrogen peroxide1 #afh ---- ---- bleaching with1 #ahb ,hydrosulphite bleach1 #aha ,hypochlorites1 #ahd ,imitations1 dyeing of1 #ic ,iron mordants1 #aai1 #afg ,iron pyrolignite1 #aai ,iron salts in tanning1 #ec ,iron tan1 #eh ,iron vitriol1 #aai ,kangaroo1 #ab ,keratin1 #be ,kicker1 #fa ,killing1 #ih1 #ajf ---- formulas1 #ajh ---- nature of1 #ajg ---- purpose of1 #ajf ---- by brush process1 #aaa ---- by dip process1 #aaa ---- with caustic soda1 #aac ---- with lime1 #aab ---- with soda1 #aab ,knapp1 #df1 #eg ,knife1 beaming1 #ch ---- shaving1 #ch ---- fleshing1 #ch ,kolinsky1 #e1 #ab ,krimmer1 #e1 #ab1 #ac ,lactic acid1 #dd1 #ea ,lactic acid fermentation1 #ej ,lambs1 #ab ---- dressing of1 #ej1 #ec ---- dyeing of1 #ib1 #adj1 #ada1 #adb ,lard1 #fj ,lead1 acetate1 #abf ,lead sulphide dye1 #abf ,leather1 definition of1 #dh ---- dressing of1 #cj ,leopard1 #e1 #ac1 #id ---- tanning of1 #dc ,lima wood1 #ace ,lime1 #ajh1 #aaj1 #aab ,linseed oil1 #fj ,litharge1 #aji ,loft drying1 #gb ,logwood1 #acc ---- blacks1 #aci ---- shades with1 #acd ,lynx1 #e1 #ac ---- imitation on rabbit and hare1 #abf ,luster of hair1 #bc ,machines used in brush dyeing1 #ajb ---- ---- dip dyeing1 #ajc ,marmot1 #ad1 #fh1 #id ,marten1 blending of1 #ia1 #ajd ,marten1 baum1 #e1 #ad ---- stone1 #e1 #ad ---- ---- imitation1 #abf ,medulla1 #bb ,meunier1 #df ,mineral colors1 #abe ---- oils1 #ei1 #fc ---- tans1 #di1 #ec ,mink1 #e1 #ad1 #fh1 #id ,mole1 #e1 #ae ---- tanning of1 #ed ,monkey1 #ae ,mordanting1 #ih1 #aad ,mordants1 alkaline1 #aba ---- aluminum1 #aah ---- chrome-copper1 #afg ---- chromium1 #abj1 #aff ---- copper1 #aai1 #aff ---- copper-iron1 #afg ---- iron1 #aai1 #afg ---- tin1 #aba ,mucines1 #be ,muskrat1 #e1 #ae1 #fh1 #id ---- imitation seal on1 #add1 #afi ,neats-foot oil1 #fj1 #fc ,neradol ,d41 #fd ,nigraniline1 #adg ,non-drying oils1 #fj1 #fc ,novelty shades1 dyeing of1 #ib ,nutgalls1 #cc1 #acb ,nutria1 #e1 #ae1 #id ,oiling1 #fb1 #gg ,oils1 drying1 #fj ---- non-drying1 #ej ---- partially-drying1 #fj1 #fc ,olive oil1 #fj ,one-bath aniline black1 #adi ,opossum1 #e1 #ae1 #fh ---- black on1 #adj ---- skunk imitation on1 #ach ---- seal imitation on1 #add ,otter1 ,river1 #e1 #af1 #id ---- ,sea1 #e1 #af ,over-hair1 #bd ,oxidation aniline black1 #aej ---- colors1 #aee ---- ---- shades with1 #afe ,para-amido phenol1 #aec1 #aeg ,para-phenylene diamine1 #aec1 #aeg1 #afb ,partially-drying oils1 #fj1 #fc ,pelage1 #b ,pelt1 #b ,pernambuco wood1 #ace ,peroxide of hydrogen1 #afh1 #ahb ,peroxides1 #ahb ,persian lamb1 #e1 #ab ---- ---- dressing of1 #ej1 #ec ---- ---- dyeing of1 #aci ,physical theories of tanning1 #dg ,pickle1 #di ,pigment granules1 #bc ,pony1 ,russian1 #e1 #af ,potassium permanganate as a dye1 #abg ---- ---- as a bleach1 #ahc ,protective-hair1 #bd ,pyrolignite of iron1 #aai ,quercitron1 #ace ,quinone di-imine1 #afc ,rabbit1 #f1 #ag1 #id ---- imitation seal on1 #add ---- lynx imitation on1 #abf ---- sable imitation on1 #afh ---- stone 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bisulphite1 #abg1 #aha ---- chloride1 #di ---- peroxide1 #ahb ---- sulphite1 #aha ,soft water1 #hg ,softening skins1 #ch ,souring1 #aac ,squirrel1 #f1 #ai ,staking1 #gh ,stannous chloride1 #aba ,stiasny1 #fd ,stone marten imitation1 #abf ,stretching1 #gh ---- machines1 #gh ,sugar of lead1 #abf ,sulphonated oils1 #fc ,sulphuric acid1 #di ,sulphurous acid bleach1 #ahj ,sumach1 #abh1 #acc ---- tanning with1 #cc ,surface water1 #hg ,sweat-glands1 #bb ,tallow1 #fj ,tanned furs1 qualities of1 #dh ,tanning methods1 comparison of1 #fe ,tannins1 #cb1 #acb ,tiger1 #ai ,top-hair1 #bd ,train oils1 #fc ,tramping machine1 #fa ,turmeric1 #acf ,under-hair1 #bd ,under-wool1 #bd ,ungreenable aniline black1 #adh ,unhairing1 #hb ---- machine1 #hc ,ursol dyes1 #aeg1 #afe ,vanadium compounds1 #adg ,vat dyes1 #agg ,vegetable dyes1 #abh1 #acf ---- oils1 #ei ---- tans1 #di1 #fe ,verdigris1 #abj ,water1 hard1 #hg ---- soft1 #hg ,whale oil1 #fj ,white fox1 bleaching of1 #agi ,wolf1 #f1 #ai ,wolverine1 #f1 #bj ,wombat1 #bj ,wood dyes1 #abh ,yellow wood1 #acd ,,literature ,,of ,,the ,,chemical ,,industries ,on our shelves is the most complete stock of technical1 industrial1 engineering and scientific books in the ,united ,states4 ,the technical literature of every trade is well represented1 as is also the literature relating to the various sciences1 both the books useful for reference as well as those fitted for students' use as textbooks4 ,a large number of these we publish and for an ever increasing number we are the sole agents4 ,,all ,,inquiries ,,made ,,of ,,us ,,are ,,cheerfully ,,and ,,carefully ,,answered ,,and ,,complete ,,catalogs ,,as ,,well ,,as ,,special ,,lists ,,sent ,,free ,,on ,,request ,illustration ,d4 ,,van ,,nostrand ,,company ,publishers and ,booksellers #h ,,warren ,,street ,,new ,,york 99 99 99 99 99 ,transcriber's ,notes3 ,punctuation has been standardised--in particular1 missing periods and quotation marks have been supplied where obviously required4 ,three entries in the bibliography were located out of alphabetical order1 and have been moved accordingly 7,fougerat1 ,lamb1 ,martin74 ,all other original errors and inconsistencies have been retained1 except as follows3 ,page #g3 changed ,enclyclopedia to ,encyclopedia 7in ,encyclopedia ,britannica1 #aath ,ed47 ,page #bj3 changed ,kaola to ,koala 7,koala or ,australian ,bear47 ,page #fb3 changed partiular to particular 7on the particular fur treatment7 ,page #fg3 changed degress to degrees 7almost #aj degrees higher than7 ,page #gc3 changed samewhat to somewhat 7based on a somewhat different7 ,page #ic3 changed imitatations to imitations 7dyeing of imitations to a great7 ,page #aja3 changed diagramatically to diagrammatically 7and ,b shows diagrammatically1 machines7 ,page #abh3 changed conjuction to conjunction 7which in conjunction with certain7 ,page #acf3 changed curcuma to ,curcuma 7stem of the ,curcuma tinctoria17 ,page #acg3 changed simutaneously to simultaneously 7and dye simultaneously2 and third7 ,page #adj3 changed atmopheric to atmospheric 7aid of the atmospheric oxygen47 ,page #adb3 changed followlowing to following 7successively in the following baths37 ,page #adi3 changed ozidizing to oxidizing 7is also an oxidizing agent and7 ,page #aed3 changed dryig to drying 7several times1 drying each time at7 ,page #afa3 changed manufacurers to manufacturers 7,other manufacturers of coal-tar7 ,page #agj3 changed ,racoon to ,raccoon 7,imitation ,skunk on ,raccoon7 ,page #ahe3 changed ,werkstatte to ,werksttte 7,halle 8,werksttte der heutigen7 ,page #ahe3 changed ,gerben to ,gerbens 7,geschichte des ,gerbens und der7 ,page #ahe3 changed ,astringentien to ,adstringentien 7und der ,adstringentien0 #aiag7