,,scientific ,,culture1   ,,and ,,other 
,,essays4    ,,by   ,,josiah ,,parsons  
,,cooke1 ,,ll4 ,d41   ,,professor ,,of  
,,chemistry ,,and ,,mineralogy1 ,,in    
,,harvard ,,college4    ,,second        
,,edition2 ,,with ,,additions4    ,,new 
,,york3   ,d4 ,,appleton ,,and          
,,company1   #a1 #c1 ,,and #e ,,bond    
,,street4   #ahhe4      ,,copyright1    
#ahha1 #ahhe1   ,,by ,,josiah ,,parsons 
,,cooke4      ,,to   ,,my ,,associates  
,,in   ,,the ,,chemical ,,laboratory    
,,of   ,,harvard ,,college   ,,this     
,,volume   ,,is   ,,affectionately      
,,dedicated4     ,,preface4   ,the      
essays collected in this volume1        
although written for special occasions  
without reference to each other1 have   
all a bearing on the subject selected as
 the title of the volume1 and are an    
outcome of a somewhat large experience  
in teaching physical science to college 
students4 ,thirty years ago1 when the   
writer began his work at ,cambridge1    
instruction in the experimental sciences

 was given in our ,american colleges    
solely by means of lectures and         
recitations4 ,chemistry and ,physics    
were allowed a limited space in the     
college curriculum as branches of useful
 knowledge1 but were regarded as wholly 
subordinate to the classics and         
mathematics as a means of education2 and
 as physical science was then taught1   
there can be no question that the       
accepted opinion was correct4           
,experimental science can never be made 
of value as a means of education unless 
taught by its own methods1 with the one 
great aim in view to train the faculties
 of the mind so as to enable the        
educated man to read the ,book of       
,nature for himself4  ,since the period 
just referred to1 the example early set 
at ,cambridge of making the student's   
own observations in the laboratory or   
cabinet the basis of all teaching1      
either in experimental or natural       
history science1 has been generally     
followed4 ,but in most centers of       

education the old traditions so far     
survive that the great end of scientific
 culture is lost in attempting to       
conform even laboratory instruction to  
the old academic methods of recitations 
and examinations4 ,these1 as usually    
conducted1 are simply hindrances in a   
course of scientific training1 because  
they are no tests of the only ability or
 acquirement which science values1 and  
therefore set before the student a false
 aim4 ,to point out this error1 and to  
claim for science teaching its          
appropriate methods1 was one object of  
the writer in these essays4  ,it is1    
however1 too often the case that1 in    
following out our theories of education1
 we avoid ,scylla only to encounter     
,charybdis1 and so1 in specializing our 
courses of laboratory instruction1 there
 is great danger of falling into the    
mechanical routine of a technical art1  
and losing sight of those grand ideas   
and generalizations which give breadth  
and dignity to scientific knowledge4    

,that these great truths are as         
important an element of scientific      
culture as experimental skill1 the      
author has also endeavored to           
illustrate1 and he has added brief      
notices of the lives of two noble men of
 science which may add force to the     
illustrations4     ,,contents4          
,,page      ,i4--,,scientific ,,culture 
#e     ,,ii4--,,the ,,nobility ,,of     
,,knowledge                             
#de    ,,iii4--,,the ,,elementary       
,,teaching ,,of ,,physical ,,science    
#ga     ,,iv4--,,the ,,radiometer       
#hf      ,v4--,,memoir ,,of ,,thomas    
,,graham                                
#abg     ,,vi4--,,memoir ,,of ,,william 
,,hallowes ,,miller                     
#ade    ,,vii4--,,william ,,barton      
,,rogers                                
#afj                                    
,,viii4--,,jean-,,baptiste-,,andre      
,,dumas                                 
#aha     ,,ix4--,,the ,,greek ,,question
                                        

#bjc      ,x4--,,further ,,remarks ,,on 
,,the ,,greek ,,question                
#bad     ,,xi4--,,scientific ,,culture2 
,,its ,,spirit1 ,,its ,,aim1 ,,and ,,its
 ,,methods  #bbg    ,,xii4--,,noblesse  
,,oblige                                
#bfg   ,,xiii4--,,the ,,spiritual ,,life
                                        
#bhi     ,,essays4     ,i4  ,,scientific
 ,,culture4      ,an ,address delivered 
,july #g1 #ahge1 at the ,opening of the 
,summer     ,courses of ,instruction in 
,chemistry1 at ,harvard ,university4    
,you have come together this morning to 
begin various elementary courses of     
instruction in chemistry and mineralogy4
 ,as ,i have been informed1 most of you 
are teachers by profession1 and your    
chief object is to become acquainted    
with the experimental methods of        
teaching physical science1 and to gain  
the advantages in your study which the  
large apparatus of this university is   
capable of affording4  ,in all this ,i  
hope you will not be disappointed4 ,you1

 as teachers1 know perfectly well that  
success must depend1 first of all1 on   
your own efforts2 but1 since the methods
 of studying ,nature are so different   
from those with which you are familiar  
in literary studies1 ,i feel that the   
best service ,i can render1 in this     
introductory address1 is to state1 as   
clearly as ,i can1 the great objects    
which should be kept in view in the     
courses on which you are now entering4  
,by your very attendance on these       
courses you have given the strongest    
evidence of your appreciation of the    
value of chemical studies as a part of  
the system of education1 and let me say1
 in the first place1 that you have not  
overvalued their importance4 ,the       
elementary principles and more          
conspicuous facts of chemistry are so   
intimately associated with the          
experience of every-day life1 and find  
such important applications in the      
useful arts1 that no man at the present 
day can be regarded as educated who is  

ignorant of them4 ,not to know why the  
fire burns1 or how the sulphur trade    
affects the industries of the world1    
will be regarded1 by the generation of  
men among whom your pupils will have to 
win their places in society1 as a       
greater mark of ignorance than a false  
quantity in ,latin prosody or a solecism
 in grammar4  ,moreover1 ,i need not    
tell you that physical science has      
become a great power in the world4      
,indeed1 after religion1 it is the      
greatest power of our modern            
civilization4 ,consider how much it has 
accomplished during the last century    
toward increasing the comforts and      
enlarging the intellectual vision of    
mankind4 ,the railroad1 the steamship1  
the electric telegraph1 photography1    
gaslights1 petroleum oils1 coal-tar     
colors1 chlorine bleaching1 anaesthesia1
 are a few of its recent material gifts 
to the world2 and not only has it made  
one pair of hands to do the work of     
twenty1 but it has so improved and      

facilitated the old industries that what
 were luxuries to the fathers of our    
republic have become necessities to our 
generation4  ,and when1 passing from    
these material fruits1 you consider the 
purely intellectual triumphs of physical
 science1 such as those which have been 
gained with the telescope1 the          
microscope1 and the spectroscope1 you   
can not wonder at the esteem in which   
these branches of study are held in this
 practical age of the world4  ,now1     
these immense results have been gained  
by the application to the study of      
,nature of a method which was so        
admirably described by ,lord ,bacon in  
his ,novum ,organon1 and which is now   
generally called the experimental       
method4 ,what we observe in ,nature is  
an orderly succession of phenomena4 ,the
 ancients speculated about these        
phenomena as well as ourselves1 but they
 contented themselves with speculations1
 animating ,nature with the products of 
their wild fancies4 ,their great master1

 ,aristotle1 has never been excelled in 
the art of dialectics2 but his method of
 logic applied to the external world was
 of very necessity an utter failure4 ,it
 is frequently said1 in defense of the  
exclusive study of the records of       
ancient learning1 that they are the     
products of thinking1 loving1 and hating
 men1 like ourselves1 and it is claimed 
that the study of science can never rise
 to the same nobility because it deals  
only with lifeless matter4 ,but this is 
a mere play on words1 a repetition of   
the error of the old schoolmen4         
,physical science is noble because it   
does deal with thought1 and with the    
very noblest of all thought4 ,nature at 
once manifests and conceals an ,infinite
 ,presence3 her methods and orderly     
successions are the manifestations of   
,omnipotent ,will2 her contrivances and 
laws the embodiment of ,omniscient      
,thought4 ,the disciples of ,aristotle  
so signally failed simply because they  
could see in ,nature only a reflection  

of their idle fancies4 ,the followers of
 ,bacon have so gloriously succeeded    
because they approached ,nature as      
humble students1 and1 having first      
learned how to question her1 have been  
content to be taught and not sought to  
teach4 ,the ancient logic never relieved
 a moment of pain1 or lifted an ounce of
 the burden of human misery4 ,the modern
 logic has made a very large share of   
material comfort the common heritage of 
all civilized men4  ,in what1 then1 does
 this ,baconian system consist8 ,simply 
in these elements3 #a4 ,careful         
observation of the conditions under     
which a given phenomenon occurs2 #b4    
,the varying of these conditions by     
experiments1 and observing the effects  
produced by the variation4 ,we thus find
 that some of the conditions are merely 
accidental circumstances1 having no     
necessary connection with the           
phenomenon1 while others are its        
invariable antecedent4 ,having now      
discovered the true relations of the    

phenomenon we are studying1 a happy     
guess1 suggested probably by analogy1   
furnishes us with a clew to the real    
causes on which it depends4 ,we next    
test our guess by further experiments4  
,if our hypothesis is true1 this or that
 must follow2 and1 if in all points the 
theory holds1 we have discovered the law
 of which we are in search4 ,if1        
however1 these necessary inferences are 
not realized1 then we must abandon our  
hypothesis1 make another guess1 and test
 that in its turn4 ,let me illustrate by
 two well-known examples3  ,the1 of old1
 universally accepted principle that all
 living organisms are propagated by     
seeds or germs 7omnia ex ovo7 has been  
seriously questioned by a modern school 
of naturalists4 ,various observers have 
maintained that there were conditions   
under which the lower forms of organic  
life were developed independently of all
 such accessories1 but other1 and       
equally competent1 naturalists1 who have
 attempted to investigate the subject1  

have obtained conflicting results4      
,thus it was observed that certain low  
forms of life were quite constantly     
developed in beef juice that had been   
carefully prepared and hermetically     
sealed in glass flasks1 even after these
 flasks had been exposed for a long time
 to the temperature of boiling water4   
,here1 proclaims the new school1 is     
unmistakable evidence of spontaneous    
generation2 for1 if past experience is  
any guide1 all germs must have been     
killed by the boiling water4 ,no1 answer
 the more cautious naturalists1 you have
 not yet proved your point4 ,you have no
 right to assume that all germs are     
killed at this temperature4  ,the       
experiments1 therefore1 were repeated   
under various conditions and at         
different temperatures1 but with        
unsatisfactory results1 until ,pasteur1 
a distinguished ,french physicist1      
devised a very simple mode of testing   
the question4 ,he reasoned thus3 ,if1 as
 is generally believed1 the presence of 

invisible spores in the air is an       
essential condition of the development  
of these lower growths1 then their      
production must bear some proportion to 
the abundance of these spores4 ,near the
 habitations of animals and plants1     
where the spores are known to be in     
abundance1 the development would be     
naturally at a maximum1 and we should   
expect that the growth would diminish in
 proportion as the microscope indicated 
that the spores diminished in the       
atmosphere4  ,accordingly1 ,pasteur     
selected a region in the ,jura          
,mountains suitable for his purpose1 and
 repeated the well-known experiment with
 beef juice1 first at the inn of a town 
at the foot of the mountains1 and then  
at various elevations up to the bare    
rocks which covered the top of the      
ridge1 a height of some eight thousand  
feet4 ,at each point he sealed up beef  
juice in a large number of flasks1 and  
watched the result4 ,he found that while
 in the town the animalcules were       

developed in almost all the flasks1 they
 appeared only in two or three out of a 
hundred cases where the flasks had been 
sealed at the top of the mountain1 and  
to a proportionate extent in those      
sealed at the intermediate elevations4  
,what1 now1 did these experiments prove8
 ,simply this1 that the development of  
these organic forms was in direct       
proportion to the number of germs in the
 air4 ,it did not settle the question of
 spontaneous generation1 but it showed  
that false conclusions had been deduced 
from the experiments which had been     
cited to prove it4  ,a still more       
striking illustration of the same method
 of questioning ,nature is to be found  
in the investigation of ,sir ,humphry   
,davy1 on the composition of water4 ,the
 voltaic battery which works our        
telegraphs was invented by ,volta in    
#ahjj2 and later1 during the same year1 
it was discovered in ,london1 by        
,nicholson and ,carlisle1 that this     
remarkable instrument had the power of  

decomposing water4 ,these physicists at 
once recognized that the chief products 
of the action of the battery on water   
were hydrogen and oxygen gases1 thus    
confirming the results of ,cavendish1   
who1 in #agha1 had obtained water by    
combining these elementary substances2  
oxygen having been previously discovered
 in #agge1 and hydrogen1 at least1 as   
early as #agff4 ,it was1 however1 very  
soon also observed that there were      
always formed by the action of the      
battery on water1 besides these aeriform
 products1 an alkali and an acid1 the   
alkali collecting around the negative   
pole1 and the acid around the positive  
pole of the electrical combination4 ,in 
regard to the nature of this acid and   
alkali1 there was the greatest          
difference of opinion among the early   
experimenters on this subject4          
,cruickshanks supposed that the acid was
 nitrous acid1 and the alkali ammonia4  
,desormes1 a ,french chemist1 attempted 
to prove that the acid was muriatic     

acid2 while ,brugnatelli asserted that a
 new and peculiar acid was formed1 which
 he called the electric acid4  ,it was  
in this state of the question that ,sir 
,humphry ,davy began his investigation4 
,from the analogies of chemical science1
 as well as from the previous           
experiments of ,cavendish and           
,lavoisier1 he was persuaded that water 
consisted solely of oxygen and hydrogen 
gases1 and that the acid and alkali were
 merely adventitious products4 ,this    
opinion was undoubtedly well founded2   
but1 great disciple of ,bacon as he was1
 ,davy felt that his opinion was worth  
nothing unless substantiated by         
experimental evidence1 and accordingly  
he set himself to work to obtain the    
required proof4  ,in ,davy's first      
experiments the two glass tubes which he
 used to contain the water were         
connected together by an animal         
membrane1 and he found1 on immersing the
 poles of his battery in their          
respective tubes1 that1 besides the now 

well-known gases1 there were really     
formed muriatic acid in one tube1 and a 
fixed alkali in the other4 ,davy at     
once1 however1 suspected that the acid  
and alkali came from common salt        
contained in the animal membrane1 and he
 therefore rejected this material and   
connected the glass tubes by carefully  
washed cotton fiber1 when1 on submitting
 the water as before to the action of   
the voltaic current1 and continuing the 
experiment through a great length of    
time1 no muriatic acid appeared2 but he 
still found that the water in the one   
tube was strongly alkaline1 and in the  
other strongly acid1 although the acid  
was chiefly1 at least1 nitrous acid4 ,a 
part of the acid evidently came from the
 animal membrane1 but not the whole1 and
 the source of the alkali was as obscure
 as before4  ,davy then made another    
guess4 ,he knew that alkali was used in 
the manufacture of glass2 and it        
occurred to him that the glass of the   
tubes1 decomposed by the electric       

current1 might be the origin of the     
alkali in his experiments4 ,he therefore
 substituted for the glass tubes cups of
 agate1 which contains no alkali1 and   
repeated the experiment1 but still the  
troublesome acid and alkali appeared4   
,nevertheless1 he said1 it is possible  
that these products may be derived from 
some impurities existing in the agate   
cups1 or adhering to them2 and so1 in   
order to make his experiments as refined
 as possible1 he rejected the agate     
vessels and procured two conical cups of
 pure gold1 but1 on repeating the       
experiments1 the acid and alkali again  
appeared4  ,and now let me ask who is   
there of us who would not have concluded
 at this stage of the inquiry that the  
acid and alkali were essential products 
of the decomposition of water8 ,but not 
so with ,davy4 ,he knew perfectly well  
that all the circumstances of his       
experiments had not been tested1 and    
until this had been done he had no right
 to draw such a conclusion4 ,he next    

turned to the water he was using4 ,it   
was distilled water1 which he supposed  
to be pure1 but still1 he said1 it is   
possible that the impurities of the     
spring-water may be carried over to a   
slight extent by the steam in the       
process of distillation1 and may        
therefore exist in my distilled water to
 a sufficient amount to have caused the 
difficulty4 ,accordingly1 he evaporated 
a quart of this water in a silver dish1 
and obtained seven-tenths of a grain of 
dry residue4 ,he then added this residue
 to the small amount of water in the    
gold cones and again repeated the       
experiment4 ,the proportion of alkali   
and acid was sensibly increased4  ,you  
think he has found at last the source of
 the acid and alkali in the impurities  
of the water4 ,so thought ,davy1 but he 
was too faithful a disciple of ,bacon to
 leave this legitimate inference        
unverified4 ,accordingly1 he repeatedly 
distilled the water from a silver       
alembic until it left absolutely no     

residue on evaporation1 and then with   
water which he knew to be pure1 and     
contained in vessels of gold from which 
he knew it could acquire no taint1 he   
still again repeated the already        
well-tried experiment4 ,he dipped his   
test-paper into the vessel connected    
with the positive pole1 and the water   
was still decidedly acid4 ,he dipped the
 paper into the vessel connected with   
the negative pole1 and the water was    
still alkaline4  ,you might well think  
that ,davy would have been discouraged  
here4 ,but not in the least4 ,the path  
to the great truths which ,nature hides 
often leads through a far denser and a  
more bewildering forest than this2 but  
then there is not infrequently a blaze  
on the trees which points out the way1  
although it may require a sharp eye in a
 clear head to see the marks4 ,and ,davy
 was well enough trained to observe a   
circumstance which showed that he was   
now on the right path and heading       
straight for the goal4  ,on examining   

the alkali formed in this last          
experiment1 he found that it was not1 as
 before1 a fixed alkali1 soda or potash1
 but the volatile alkali ammonia4       
,evidently the fixed alkali came from   
the impurities of the water1 and when1  
on repeating the experiment with pure   
water in agate cups or glass tubes1 the 
same results followed1 he felt assured  
that so much at least had been          
established4 ,there was still1 however1 
the production of the volatile alkali   
and of nitrous acid to be accounted for4
 ,as these contain only the elements of 
air and water1 ,davy thought that       
possibly they might be formed by the    
combination of hydrogen at the one pole 
and of oxygen at the other with the     
nitrogen of the air1 which was          
necessarily dissolved in the water4 ,in 
order1 therefore1 to eliminate the      
effect of the air1 he again repeated the
 experiment under the receiver of an    
air-pump from which the atmosphere had  
been exhausted1 but still the acid and  

alkali appeared in the two cups4  ,davy1
 however1 was not discouraged by this1  
for the blazes on the trees were        
becoming more numerous1 and he now felt 
sure that he was fast approaching the   
end4 ,he observed that the quantity of  
acid and alkali had been greatly        
diminished by exhausting the air1 and   
this was all that could be expected1    
for1 as ,davy knew perfectly well1 the  
best air-pumps do not remove all the    
air4 ,he therefore1 for the last        
experiment1 not only exhausted the air1 
but replaced it with pure hydrogen1 and 
then exhausted the hydrogen and refilled
 the receiver with the same gas several 
times in succession1 until he was       
perfectly sure that the last traces of  
air had been as it were washed out4 ,in 
this atmosphere of pure hydrogen he     
allowed the battery to act on the water1
 and not until the end of twenty-four   
hours did he disconnect the apparatus4  
,he then dips his test-paper into the   
water connected with the positive pole1 

and there is no trace of acid2 he dips  
it into the water at the negative pole1 
and there is no alkali2 and you may     
judge with what satisfaction he         
withdraws those slips of test-paper1    
whose unaltered surfaces showed that he 
had been guided at last to the truth1   
and that his perseverance had been      
rewarded4  ,the fame of ,sir ,humphry   
,davy rests on his discovery of the     
metals of the alkalies and earths which 
first revealed the wonderful truth that 
the crust of our globe consists of      
metallic cinders2 but none of these     
brilliant results show so great         
scientific merit or such eminent power  
of investigating ,nature as the         
experiments which ,i have just detailed4
 ,i have not1 however1 described them   
here for the purpose of glorifying that 
renowned man4 ,his honored memory needs 
no such office at my hands4 ,my only    
object was to show you what is meant by 
the ,baconian method of science1 and to 
give some idea of the nature of that    

modern logic which within the last fifty
 years has produced more wonderful      
transformations in human society than   
the author of ,aladdin ever imagined in 
his wildest dreams4 ,in this short      
address ,i can of course give you but a 
very dim and imperfect idea of what ,i  
have called the ,baconian system of     
experimental reasoning4 ,indeed1 you can
 not form any clear conception of it1   
until in some humble way you have       
attempted to use the method1 each one   
for himself1 and you have come here in  
order that you may acquire such         
experience4  ,my object1 however1 will  
be gained if these illustrations serve  
to give emphasis to the following       
statements1 which ,i feel ,i ought to   
make at the opening of these courses of 
instruction--statements which have an   
especial appropriateness in this place1 
since ,i am addressing teachers1 who are
 in a position to exert an important    
influence on the system of education in 
this country4  ,in the first place1     

then1 ,i must declare my conviction that
 no educated man can expect to realize  
his best possibilities of usefulness    
without a practical knowledge of the    
methods of experimental science4 ,if he 
is to be a physician1 his whole success 
will depend on the skill with which he  
can use these great tools of modern     
civilization4 ,if he is to be a lawyer1 
his advancement will in no small measure
 be determined by the acuteness with    
which he can criticise the manner in    
which the same tools have been used by  
his own or his opponent's clients4 ,if  
he is to be a clergyman1 he must take   
sides in the great conflict between     
theology and science which is now raging
 in the world1 and1 unless he wishes to 
play the part of the doughty knight ,don
 ,quixote1 and think he is winning great
 victories by knocking down the         
imaginary adversaries which his         
ignorance has set up1 he must try the   
steel of his adversary's blade4  ,let me
 be fully understood4 ,it is not to be  

expected or desired that many of our    
students should become professional men 
of science4 ,the places of employment   
for scientific men are but few1 and more
 in the future than in the past they    
will naturally be secured by those whom 
,nature has endowed with special        
aptitudes or tastes--usually the signs  
of aptitudes--to investigate her laws4  
,that our country will always offer an  
honorable career to her men of genius1  
we have every reason to expect1 and     
these born students of ,nature will     
usually follow the plain indications of 
,providence without encouragement or    
direction from us4  ,it is different1   
however1 with the great body of earnest 
students who are conscious of no special
 aptitudes1 but who are desirous of     
doing the best thing to fit themselves  
for usefulness in the world2 and ,i feel
 that any system of education is        
radically defective which does not      
comprise a sufficient training in the   
methods of experimental science to make 

the mass of our educated men familiar   
with this tool of modern civilization3  
so that1 when1 hereafter1 new conquests 
over matter are announced and great     
discoveries are proclaimed1 they may be 
able not only to understand but also to 
criticise the methods by which the      
assumed results have been reached1 and  
thus be in a position to distinguish    
between the true and the false4 ,whether
 we will or not1 we must live under the 
direction of this great power of modern 
society1 and the only question is       
whether we will be its ignorant slave or
 its intelligent servant4  ,in the      
second place1 it seems fitting that ,i  
should state to you what ,i regard as   
the true aims to be kept in view in a   
course of scientific study1 and to give 
my reasons for the methods we have      
adopted in arranging the courses you are
 about beginning4  ,in our day there has
 arisen a warm discussion as to the     
relative claims of two kinds of culture1
 and attempts are made to create an     

antagonism between them4 ,but all       
culture is the same in spirit4 ,its     
object is to awaken and strengthen the  
powers of the mind2 for these1 like the 
muscles of the body1 are developed and  
rendered strong and active only by      
exercise2 while1 on the other hand1 they
 may become atrophied from mere want of 
use4 ,science culture differs in its    
methods from the old classical culture1 
but it has the same spirit and the same 
object4 ,you must not1 therefore1 expect
 me to advocate the former at the       
expense of the latter2 for1 although ,i 
have labored assiduously during a       
quarter of a century to establish the   
methods of science teaching which have  
now become general1 ,i am far from      
believing that they are the only true   
modes of obtaining a liberal education4 
,so far from this1 if it were necessary 
to choose one of two systems1 ,i should 
favor the classical2 and why8  ,language
 is the medium of thought1 and can not  
be separated from it4 ,he who would     

think well must have a good command of  
language1 and he who has the best       
command of language ,i am almost tempted
 to say will think the best4 ,for this  
reason a certain amount of critical     
study of language is essential for every
 educated man1 and such study is not    
likely to be gained except through the  
great ancient languages2 the advocates  
of classical scholarship frequently say1
 can not be gained4 ,i am not ready to  
accept this dictum2 but ,i most         
willingly concede that in the present   
state of our schools it is not likely to
 be gained4 ,i never had any taste      
myself for classical studies2 but ,i    
know that ,i owe to the study a great   
part of the mental culture which has    
enabled me to do the work that has      
fallen to my share in life4  ,but1 while
 ,i concede all this1 ,i do not believe1
 on the other hand1 that the classical  
is the only effective method of culture2
 you evidently do not think so1 for you 
would not be here if you did4 ,but1 in  

abandoning the old tried method1 which  
is known to be good1 for the new1 you   
must be careful that you gain the       
advantages which the new offers2 and you
 will not gain the new culture you seek 
unless you study science in the right   
way4 ,in the classical departments the  
methods are so well established1 and    
have been so long tested by experience1 
that there can hardly be a wrong way4   
,but in science there is not only a     
wrong way1 but this wrong way is so easy
 and alluring that you will most        
certainly stray into it unless you      
strive earnestly to keep out of it4     
,hence ,i am most anxious to point out  
to you the right way1 and do what ,i can
 to keep you in it2 and you will find   
that our courses and methods have been  
devised with this object4  ,when        
advocating in our mother ,university of 
,cambridge1 in ,old ,england1 the claims
 of scientific culture1 ,i was pushed   
with an argument which had very great   
weight with the eminent ,english        

scholars present1 and which you will be 
surprised to learn was regarded as fatal
 to the success of the science triposes 
then under debate4 ,the argument was    
that the experimental sciences could not
 be made the subjects of competitive    
examinations4 ,some may smile at such an
 objection2 but1 as viewed from the     
,english standpoint1 there was really a 
great deal in it1 and the argument      
brought out the radical difference      
between scientific and classical        
culture4  ,the old method of culture may
 be said to have culminated in the      
competitive examinations of the ,english
 universities4 ,we have no such         
examinations here4 ,success depends not 
simply on knowing your subject          
thoroughly1 but on having it at your    
fingers' ends1 and those fingers so     
agile that they can accomplish not only 
a prodigious amount of work in a short  
time1 but can do this work with absolute
 accuracy4 ,for the only approach we    
make to an experience of this kind1 we  

must look to our athletic contests4 ,it 
may of course be doubted whether the    
ability1 once in a man's life1 to       
perform such mental feats1 is worth what
 it costs4 ,still it implies a very high
 degree of mental culture1 and it is    
perfectly certain that the experimental 
sciences give no field for that sort of 
mental prize-fights4 ,it is easy to     
prepare written examinations which will 
show whether the students have been     
faithful to their work1 but they can not
 be adapted to such competitions as ,i  
have described without abandoning the   
true object of science culture4 ,the    
ability of the scientific student can   
only be shown by long-continued work at 
the laboratory table1 and by his success
 in investigating the problems which    
,nature presents4  ,we have here struck 
the true key-note of the scientific     
method4 ,the great object of all our    
study should be to study ,nature1 and   
all our methods should be directed to   
this one object4 ,this aim alone will   

ennoble our scholarship as students1 and
 will give dignity to our scientific    
calling as men of science4 ,it is this  
high aim1 moreover1 which vindicates the
 worth of the mode of culture we have   
chosen4 ,what is it that ennobles       
literary culture but the great minds    
which1 through this culture1 have       
honored the nations to which they       
belong8  ,the culture we have chosen is 
capable of even greater things2 not     
because science is nobler than art1 for 
both are equally noble--it is the       
thought1 the conception1 which ennobles1
 and ,i care not whether it be attained 
through one kind of exercise of the     
mental faculties or another--but we are 
capable of grander and nobler thoughts  
than ,plato1 ,cicero1 ,shakespeare1 or  
,newton1 because we live in a later     
period of the world's history1 when1    
through science1 the world has become   
richer in great ideas4 ,it is1 ,i       
repeat1 the great thought which         
ennobles1 and it ennobles because it    

raises to a higher plane that which is  
immortal in our manhood4  ,if ,i have   
made my meaning clear1 and if you       
sympathize with my feelings1 you will   
understand why ,i regard culture as so  
important to the individual and to the  
nation4 ,the works of ,shakespeare and  
of ,bacon are of more value to ,england 
to-day than the memories of ,blenheim or
 ,trafalgar2 and those great minds will 
still be living powers in the world when
 ,marlborough and ,nelson are only      
remembered as historical names4  ,i     
therefore believe that it is the first  
duty of a country to foster the highest 
culture1 and that it should be the aim  
of every scholar to promote this culture
 both by his own efforts and his active 
influence4 ,a nation can become really  
great in no other way4 ,we live in a    
country of great possibilities2 and the 
danger is that1 as with many men ,i have
 known in college1 of great potential   
abilities1 the greatness will end where 
it begins4 ,the scholars of the country 

should have but one voice in this       
matter1 and urge upon the government and
 upon individuals the duty of           
encouraging and supporting mental       
culture for its own sake4  ,the time has
 passed when we can afford to limit the 
work of our higher institutions of      
learning to teaching knowledge already  
acquired4 ,henceforth the investigation 
of unsolved problems1 and the discovery 
of new truth1 should be one of the main 
objects at our ,american universities1  
and no cost grudged which is required to
 maintain at them the most active minds1
 in every branch of knowledge which the 
country can be stimulated to produce4   
,i could urge this on the self-interest 
of the nation as an obvious dictate of  
political economy4 ,i could say1 and say
 truly1 that the culture of science will
 help us to develop those latent        
resources of which we are so proud2 will
 enable us to grow two blades of grass  
where one grew before2 to extract a     
larger percentage of metal from our     

ores2 to economize our coal1 and in     
general to direct our waiting energies  
so that they may produce a more abundant
 pecuniary reward4 ,i could tell of     
,galvani studying for twenty long years1
 to no apparent purpose1 the twitching  
of frogs' hind-legs1 and thus sowing the
 seed from which has sprung the greatest
 invention of modern times4 ,or1 if our 
,yankee impatience would be unwilling to
 wait half a century for the fruit to   
ripen1 ,i could point to the purely     
theoretical investigations of organic   
chemistry1 which in less than five years
 have revolutionized one of the great   
industries of ,europe1 and liberated    
thousands of acres for a more beneficent
 agriculture4 ,this is all true1 and may
 be urged properly if higher            
considerations will not prevail4 ,it is 
an argument ,i have used in other       
places1 but ,i will not use it here2    
although ,i gladly acknowledge the      
,providence which brings at last even   
material fruits to reward conscientious 

labor for the advancement of knowledge  
and the intellectual elevation of       
mankind4 ,i would rather point to that  
far greater multitude who worked in     
faith for the love of knowledge1 and who
 ennobled themselves and ennobled their 
nation1 not because they added to its   
material prosperity1 but because they   
made themselves and made their fellows  
more noble men4  ,i come back now again 
to the moral of all this1 to urge upon  
you1 as the noblest patriotism and the  
most enlightened self-interest1 the duty
 of striving for yourselves and         
encouraging in others the highest       
culture in the studies you have chosen1 
and this culture with one end in view1  
to advance knowledge4 ,i am far1 of     
course1 from advising you to grapple    
immaturely with unsolved problems1 or1  
when you have gained the knowledge with 
which you can dare to venture from the  
beaten track1 to undertake work beyond  
your power4 ,many a young scientific man
 has suffered the fate of ,icarus in    

attempting to soar too high4 ,moreover1 
,i am far from expecting that all or    
many of you will ever have the          
opportunity of going beyond the         
well-explored fields of knowledge2 but  
you can all have the aim1 and that aim  
will make your work more worthy and more
 profitable to yourselves4 ,every       
,american boy can not be ,president of  
the ,united ,states1 but if1 as our     
,english cousins allege1 he believes    
that he can be1 the very belief makes   
him an abler man4  ,we have dwelt long  
enough on these generalities1 and it is 
time to come down to commonplaces1 and  
to inquire what are the essential       
conditions of this scientific culture   
which shall fit us to investigate       
,nature2 and the first thought that     
occurs to me in this connection may be  
expressed thus3 ,science presents to us 
two aspects1 which ,i may call its      
objective and its subjective aspect4    
,objectively it is a body of facts1     
which we have to observe1 and           

subjectively it is a body of truths1    
conclusions1 or inferences1 deduced from
 these facts2 and the two sides of the  
subject should always be kept in view4  
,i propose next to say a few words in   
regard to each of these two aspects of  
our study1 and in regard to the best    
means of training our faculties so as to
 work successfully in each sphere4      
,first1 then1 success in the observation
 of phenomena implies three qualities at
 least1 namely1 quickness and sharpness 
of perception1 accuracy in details1 and 
truthfulness2 and on its power to       
cultivate these qualities a large part  
of the value of science1 as a means of  
education1 depends4  ,to begin with the 
cultivation of our perceptions4 ,we are 
all gifted with senses1 but how few of  
us use them to the best advantage6 ,we  
have eyes and see not2 for1 although the
 light paints the picture on the retina1
 our dull perceptions give no attention 
to the details1 and we retain only a    
confused impression of what has passed  

before our eyes4 ,but how1 you may ask1 
are we to cultivate this sharpness of   
perception8 ,i answer1 only by making a 
conscious effort to fix our attention on
 the objects we study until the habit   
becomes a second nature4 ,i have often  
noticed1 with surprise1 the power which 
uneducated miners frequently possess of 
recognizing many minerals at sight4     
,this they have acquired by long        
experience and close familiarity with   
such objects1 and such power of         
observation is with them so purely a    
habit that they are frequently unable to
 state clearly the grounds on which     
their conclusions are based4 ,they      
recognize the minerals by what in common
 language is called their looks and they
 notice delicate differences in the     
looks to which most men are blind4 ,it  
is1 however1 the business of the        
scientific mineralogist to analyze these
 looks1 and to point out in what the    
differences consist2 so that by fixing  
his attention on these points the       

student may gain1 by a few hours' study1
 the power which the miner acquires only
 after long experience4  ,the chief     
difficulty1 however1 which we find in   
teaching mineralogy is1 that the        
students do not readily see the         
differences when they are pointed out1  
or1 if they see them1 do not remember   
them with sufficient precision to render
 their subsequent observations          
conclusive and precise4 ,this either    
arises from a failure to cultivate the  
powers of observation in childhood1 or  
the subsequent blunting of them by      
disuse4 ,the ladies will scout the idea 
that a brooch of cut-glass is as        
ornamental as one of diamond1 and yet ,i
 venture to assert that there is not one
 person in fifty1 at least of those who 
have not made a study of the subject1   
who can tell the difference between the 
two4 ,the external appearance depends   
simply on what we call lustre4 ,the     
lustre of glass is vitreous1 that of the
 diamond adamantine2 and ,i know of no  

other distinction which it is more      
difficult for students to recognize than
 this4 ,those of you who study          
mineralogy will experience this         
difficulty1 and it can be overcome only 
by giving careful attention to the      
subject4 ,the teacher can do nothing    
more than put in your hands the         
specimens which illustrate the point1   
and you must study these specimens until
 you see the difference4 ,it is a       
question of sight1 not of understanding1
 and all the optical theories of the    
cause of the lustre will not help you in
 the least toward seeing the difference 
between diamond and glass1 or anglesite 
and heavy spar4  ,another illustration  
of the same fact is the constant failure
 of students to distinguish by the eye  
alone between the two minerals called   
copper-glance and gray copper4 ,there is
 a difference of color and lustre which1
 although usually well marked1 it       
requires an educated eye to distinguish4
  ,mineralogy undoubtedly demands a more

 careful cultivation of the perceptions 
than the other branches of chemistry2   
but still you will find abundant        
practice for close observation in them  
all4 ,i have often known students to    
reach erroneous results in qualitative  
analysis by mistaking a white           
precipitate in a colored liquid for a   
colored precipitate1 or by not attending
 to similar broad distinctions1 which   
would have been obvious to any careful  
observer2 and so in quantitative        
analysis1 mere delicacy of touch or     
handling is a great element of success4 
,but ,i must pass on to speak of the    
importance in the study of ,nature of   
accuracy in detail1 which is the second 
condition of successful observation of  
which ,i spoke4 ,we must cultivate not  
only accuracy in observing details1 but 
also accuracy in following details which
 have been laid down by others for our  
guidance4 ,in science we can not draw   
correct conclusions from our premises   
unless we are sure that we have all the 

facts1 and what seemed at first an      
unimportant detail often proves to be   
the determining condition of the result2
 and1 again1 if we are told that under  
certain conditions a certain sign is the
 proof of the presence of a certain     
substance1 we have no right to assume   
that the sign is of any value unless the
 conditions are fulfilled4 ,a black     
precipitate1 for example1 obtained under
 certain conditions1 is a proof of the  
presence of nickel1 but we can not      
assert that we have found nickel unless 
we have followed out those details in   
every particular4  ,of course1 we must  
avoid empiricism as far as we can4 ,we  
must seek to learn the reasons of the   
details1 and such knowledge will not    
only render our work intelligent1 but   
will also frequently enable us to judge 
how far the details are essential1 and  
to what extent our processes may be     
varied with safety4 ,we must also avoid 
trifling1 and1 above all1 the straining 
at a gnat and swallowing a camel1 as is 

the habit with triflers4 ,large         
knowledge and good judgment will avoid  
all such errors2 but1 if we must choose 
between fussiness and carelessness1 the 
first is the least evil4 ,slovenly work 
means slovenly results1 and habits of   
carefulness1 neatness1 and order produce
 as excellent fruits in the laboratory  
as in the home4  ,last in order but     
first in importance of the conditions of
 successful observation1 mentioned      
above1 stands truthfulness4 ,here you   
may think ,i am approaching a delicate  
subject1 of which even to speak might   
seem to cast a reproach4 ,but not so at 
all4 ,i am not speaking here of         
conscious deception1 for ,i assume that 
no one who aspires to be a student of   
,nature can be guilty of that4 ,but ,i  
am speaking of a quality whose absence  
is not necessarily a mark of sinfulness1
 but whose possession1 in a high degree1
 is a characteristic of the greatest    
scientific talent4 ,as every lawyer     
knows1 he is a rare man whose testimony 

is not colored by his interests1 and a  
very large amount of self-deception is  
compatible with conscious honesty of    
purpose4  ,so among scientific students 
the power to keep the mind unbiased1 and
 not to color our observations in the   
least degree1 is one of the rarest as it
 is one of the noblest of qualities4 ,it
 is a quality we must strive after with 
all our might1 and we shall not attain  
it unless we strive4 ,remember1 our     
observations are our data1 and1 unless  
accurate1 everything deduced from them  
must have the taint of our deception4   
,we can not deceive ,nature1 however    
much we may deceive ourselves2 and there
 is many a student who would cut off his
 right hand rather than be guilty of a  
conscious untruth1 who is yet constantly
 untruthful to himself4 ,every year     
students of mineralogy present to me    
written descriptions of mineral         
specimens which particularize1 as       
observed1 characters that do not appear 
on the specimen given them to determine1

 although they may be the correct       
characters of some other mineral4       
,there is usually no want of honesty in 
this1 but1 deceived by some accident1   
the student has made a wrong guess1 and 
then imagined that he saw on the        
specimen those characters which he knew 
from the descriptions ought to appear on
 the assumed mineral4 ,so1 also1 it not 
unfrequently happens that a student in  
qualitative analysis1 who has obtained  
some hints in regard to the composition 
of his solution1 will torture his       
observations until they seem to him to  
confirm his erroneous inferences2 and   
again the student in quantitative       
analysis1 who finds out the exact weight
 he ought to obtain1 is often insensibly
 influenced by this knowledge--in the   
washing and ignition of his precipitate1
 or in some other way--and thus obtains 
results whose only apparent fault may be
 a too close agreement with theory1 but 
which1 nevertheless1 are not accurate   
because not true4 ,it is evident how    

fatal such faults as these must be to   
the investigation of truth1 and they are
 equally destructive of all scientific  
scholarship4 ,their effect on the       
student is so marked that1 although he  
may deceive himself1 he will rarely     
deceive his teacher4 ,that he should    
lose confidence in his own results is1  
to the teacher1 one of the most marked  
indications of such false methods of    
study1 but the student usually refers   
his want of success to any cause but the
 real one--his own untruthfulness4 ,he  
will complain of the teacher1 or of the 
methods of instruction1 and may even    
persuade himself that all scientific    
results are as uncertain as his own4 ,as
 ,i have said1 mere ordinary            
truthfulness1 which spurns any conscious
 deception1 will not save us from       
falling into such faults4 ,our          
scientific study demands a much higher  
order of truthfulness than this4 ,we    
should so love the truth above all price
 as to strive for it with single-hearted

 and unswerving purpose4 ,we must be    
constantly on our guard to avoid any    
circumstance which would tend to bias   
our minds or warp our judgments1 and we 
must make the attainment of the truth   
our sole motive1 guide1 and end4  ,it   
remains for me1 before closing this     
address1 to say a few words on what ,i  
have called the subjective aspect of    
scientific study4 ,science offers us not
 only a mass of phenomena to be         
observed1 but also a body of truths     
which have been deduced from these      
observations2 and1 without the power of 
drawing correct inferences from the data
 acquired1 exact observations would be  
of little value4 ,i have already        
described the inductive method of       
reasoning1 and illustrated it by two    
noteworthy examples1 and1 in a humbler  
measure1 we must apply the same method  
in our daily work in the laboratory4 ,we
 must learn how to vary our experiments 
so as to eliminate the accidental       
circumstances1 and make evident the     

essential conditions of the phenomena we
 are studying4 ,such power can only be  
acquired by practice1 and a somewhat    
long experience in active teaching has  
convinced me that there is no better    
means of training this logical faculty  
than the study of qualitative chemical  
analysis in which many of you are to    
engage4  ,the results of the processes  
of qualitative analysis are perfectly   
definite and trustworthy2 but they are  
only reached by following out the       
indications of experiments which are    
frequently obscure1 and even apparently 
contradictory2 reconciling by new       
experiments the seeming discrepancies1  
and1 at last1 having eliminated all     
other possible causes of the phenomena  
observed1 discovering the true nature of
 the substances under examination4  ,the
 study of mineralogy affords an almost  
equally good practice1 although in a    
somewhat different form4 ,by comparing  
carefully many specimens of the same    
mineral1 you learn to distinguish the   

accidental from the essential           
characters1 and on this distinction you 
must base your inferences in regard to  
the nature of the specimens you may be  
called upon to determine4 ,a single     
remark occurs to me which may aid you in
 cultivating this scientific logic4  ,do
 not attempt to reason on insufficient  
data4 ,multiply your observations or    
experiments1 and when your premises are 
ample1 the conclusion will generally    
take care of itself4 ,are you in doubt  
in regard to a mineral specimen8 ,repeat
 your observations again and again1     
multiply them with the aid of the       
blow-pipe or goniometer1 compare the    
specimen with known specimens which it  
resembles1 until either your doubts are 
removed or you are satisfied that you   
are unequal to the task2 and remember   
that1 in many cases1 the last is the    
only honest conclusion4  ,are you in    
doubt in regard to the reactions of the 
substance you are analyzing1 whether    
they are really those of a metal you    

suspect to be present8 ,do not rest in  
such a frame of mind1 and1 above all1 do
 not try to remove the doubt by         
comparing your experience with that of  
your neighbor1 but multiply your own    
experiments2 procure some compound of   
the metal1 and compare its reactions    
with those you have observed until you  
reach either a positive or a negative   
result4  ,remember that the way to      
remove your doubts is to widen your own 
knowledge1 and not to depend on the     
knowledge of others4 ,when your         
knowledge of the facts is ample1 your   
inferences will be satisfactory1 and    
then an unexplained phenomenon is the   
guide to a new discovery4 ,do not be    
discouraged if you have to labor long in
 the dark before the day begins to dawn4
 ,it will at last dawn to you1 as it has
 dawned to others before1 and1 when the 
morning breaks1 you will be satisfied   
with the result of your labor4          
,moreover1 ,i feel confident that such  
experience will very greatly tend to    

increase your appreciation of the value 
of scientific studies in training the   
reasoning faculties of the mind4 ,this1 
as every one must admit1 is the best    
test of their utility in a scheme of    
education1 and it is precisely here that
 ,i claim for them the very highest     
place4 ,it has generally been admitted  
that mathematical studies are peculiarly
 well adapted to train the logical      
faculties1 but still many persons have  
maintained that1 since the mathematics  
deal wholly with absolute certainties1  
an exclusive devotion to this class of  
subjects unfits the mind for weighing   
the probable evidence by which men are  
chiefly guided in the affairs of life4  
,but1 without attempting to discuss this
 question1 on which much might be said  
on both sides1 it is certain that no    
such objection can be urged against the 
study of the physical sciences if       
conducted in the manner ,i have         
attempted to describe4 ,these subjects  
present to the consideration of the     

student every degree of probable        
evidence1 accustoming him to weigh all  
the evidence for or against a given     
conclusion1 and to reject or to         
provisionally accept only on the balance
 of probabilities4 ,moreover1 in        
practical science1 the student is taught
 to follow out a chain of probable      
evidence with care and caution1 to      
eliminate all accidental phenomena1 and 
supply1 by experiment or observation1   
the missing links1 until he reaches the 
final conclusion--an intellectual       
process which1 though based wholly on   
probable evidence1 may have all the     
force and certainty of a mathematical   
demonstration4  ,indeed1 that highly    
valued scientific acumen and skill which
 enables the student to brush away the  
accidental circumstances by which the   
laws of ,nature are always concealed    
until the truth stands out in bold      
relief1 is but a higher phase of the    
same talent which marks professional    
skill in all the higher walks of life4  

,the physician who looks through the    
external symptoms of his patient to the 
real disease which lurks beneath2 the   
lawyer1 who disentangles a mass of      
conflicting testimony1 and follows out  
the truth successfully to the end2 the  
statesman1 who sees beneath the froth of
 political life the great fundamental   
principles which will inevitably rule   
the conduct of the state1 and thus      
foresees and provides for the coming    
change2 the general1 who discovers amid 
the confusion of the battlefield the    
weak point of his enemy's front2 the    
merchant1 even1 who can interpret the   
signs of the unsettled market--employ   
the same faculty1 and frequently in not 
a much lower degree1 that discovered the
 law of gravitation1 and which1 since   
the days of ,newton1 has worked so      
successfully to unveil the mysteries of 
the material creation4  ,moreover1 ,i   
hope1 my friends1 that you will come to 
value scientific studies1 not simply    
because they cultivate the perceptive   

and reasoning faculties1 but also       
because they fill the mind with lofty   
ideals1 elevated conceptions1 and noble 
thoughts4 ,indeed1 ,i claim that there  
is no better school in which to train   
the aesthetical faculties of the mind1  
the tastes1 and the imagination1 than   
the study of natural science4  ,the     
beauty of ,nature is infinite1 and the  
more we study her works the more her    
loveliness unfolds4 ,the upheaved       
mountain1 with its mantle of eternal    
snow2 the majestic cataract1 with its   
whirl and roar of waters2 the sunset    
cloud1 with its blending of gorgeous    
hues1 lose nothing of their beauty for  
him who knows the mystery they conceal4 
,on the contrary1 they become1 one and  
all1 irradiated by the ,infinite        
,presence which shines through them1 and
 fill the mind with grander conceptions 
and nobler ideas than your uneducated   
child of ,nature could ever attain4     
,remember that ,i am not recommending an
 exclusive devotion to the natural      

sciences4 ,i am only claiming for them  
their proper place in the scheme of     
education1 and ,i do not1 of course1    
deny the unquestionable value of both   
the ancient and the modern classics in  
cultivating a pure and elevated taste4  
,but ,i do say that the poet-laureate of
 ,england has drawn a deeper inspiration
 from ,nature interpreted by science    
than any of his predecessors of the     
classical school2 and ,i do also affirm 
that the pre-,raphaelite school of      
painting1 with all its grotesque mimicry
 of ,nature1 embodies a truer and purer 
ideal than that of any ,roman fable or  
,grecian dream4  ,and what shall we say 
of the imagination8 ,where can you find 
a wider field for its exercise than that
 opened by the discoveries of modern    
science8 ,and as the mind wanders over  
the vast expanse1 crossing boundless    
spaces1 dwelling in illimitable time1   
witnessing the displays of immeasurable 
power1 and studying the adaptations of  
,omniscient skill1 it lives in a realm  

of beauty1 of wonder1 and of awe1 such  
as no artist has ever attained to in    
word1 in sound1 in color1 or in form4   
,and if such a life does not lead man to
 feel his own dependence1 to yearn      
toward the ,infinite ,father1 and to    
rest on the bosom of ,infinite ,love1 it
 is simply because it is not the noble  
in intellect1 not the great in talent1  
not the profound in knowledge1 not the  
rich in experience1 not the lofty in    
aspiration1 not the gifted in imagery1  
but solely the pure in heart1 who see   
,god4  ,such1 then1 is a very imperfect 
presentation of what ,i believe to be   
the value of scientific studies as a    
means of education4 ,in what ,i have    
stated ,i have implied that1 for these  
studies to be of any real value1 the end
 must be constantly kept in view1 and   
everything made subservient to the one  
great object4  ,to study the natural    
sciences merely as a collection of      
interesting facts which it is well for  
every educated man to know1 seldom      

serves a useful purpose4 ,the young mind
 becomes wearied with the details1 and  
soon forgets what it has never more than
 half acquired4 ,the lessons become an  
exercise of the memory and of nothing   
more2 and if1 as is too frequently the  
case1 an attempt is made to cram the    
half-formed mind in a single school-year
 with an epitome of half the natural    
sciences--natural philosophy1 astronomy1
 and chemistry1 physiology1 zooelogy1   
botany1 and mineralogy1 following each  
other in rapid succession--these studies
 become a great evil1 an actual         
nuisance1 which ,i should be the first  
to vote to abate4 ,the tone of mind is  
not only not improved1 but seriously    
impaired1 and the best product is a     
superficial1 smattering smartness1 which
 is the crying evil not only of our     
schools but also of our country4  ,in   
order that the sciences should be of    
value in our educational system1 they   
must be taught more from things than    
from books1 and never from books without

 the things4 ,they must be taught1 also1
 by real living teachers1 who are       
themselves interested in what they      
teach1 are interested also in their     
pupils1 and understand how to direct    
them aright4 ,above all1 the teachers   
must see to it that their pupils study  
with the understanding1 and not solely  
with the memory1 not permitting a single
 lesson to be recited which is not      
thoroughly understood1 taking the       
greatest care not to load the memory    
with any useless lumber1 and eschewing  
merely memorized rules as they would    
deadly poison4 ,the great difficulty    
against which the teachers of natural   
science have to contend in the colleges 
are the wretched tread-mill habits the  
students bring with them from the       
schools4 ,allow our students to memorize
 their lessons1 and they will appear    
respectably well1 but you might as      
easily remove a mountain as to make many
 of them think4 ,they will solve an     
involved equation of algebra readily    

enough so long as they can do it by     
turning their mental crank1 when they   
will break down on the simplest         
practical problem of arithmetic which   
requires of them only thought enough to 
decide whether they shall multiply or   
divide4  ,many a boy of good            
capabilities has been irretrievably     
ruined1 as a scholar1 by being compelled
 to learn the ,latin grammar by rote at 
an age when he was incapable of         
understanding it2 and ,i fear that      
schools may still be found where young  
minds are tortured by this stupefying   
exercise4 ,those of us who have faith in
 the educational value of scientific    
studies are most anxious that the       
students who resort to our colleges     
should be as well fitted in the physical
 sciences as in the classics1 for       
otherwise the best results of scientific
 culture can not be expected4 ,as it is1
 our students come to the university1   
not only with no preparation in physical
 science1 but with their perceptive and 

reasoning faculties so undeveloped that 
the acquisition of the elementary       
principles of science is burdensome and 
distasteful2 and good scholars1 who are 
ambitious of distinction1 can more      
readily win their laurels on the old    
familiar track than on an untried course
 of which they know nothing1 and for    
which they must begin their training    
anew4  ,we have improved our system of  
instruction in the college as fast as we
 could obtain the means1 but we are     
persuaded that the best results can not 
be reached without the cooeperation of  
the schools4 ,we feel1 therefore1 that  
it is incumbent upon us1 in the first   
place1 to do everything in our power to 
prove to the teachers of this country   
how great is the educational value of   
the physical sciences1 when properly    
taught2 and secondly1 to aid them in    
acquiring the best methods of teaching  
these subjects4 ,it is with such aims   
that our summer courses have been       
instituted1 and your presence here in   

such numbers is the best evidence that  
they have met a real want of the        
community4 ,we welcome you to the       
university and to such advantages as it 
can afford1 and we shall do all in our  
power to render your brief residence    
here fruitful1 both in experience and in
 knowledge2 hoping1 also1 that the      
university may become to you1 as she has
 to so many others1 a bright light      
shining calmly over the troubled sea of 
active life1 ever suggesting lofty      
thoughts1 encouraging noble endeavors1  
and inciting all her children to work   
together toward those great ends1 the   
advancement of knowledge and the        
education of mankind4     ,,ii4  ,,the  
,,nobility ,,of ,,knowledge4      ,an   
,address delivered before the ,free     
,institute at ,worcester1               
,massachusetts1 ,july #bh1 #ahgd4       
,within a comparatively few years       
schools for the instruction of artisans 
have become a prominent feature in the  
educational systems both of this country

 and of ,europe1 and seem destined to   
supersede the old system of             
apprenticeships4 ,the establishment of  
these schools has been an important step
 in human progress1 not because any     
great advantage has been gained in the  
cultivation of mechanical skill1 but    
because here the future mechanic        
acquires culture of the mind as well as 
skill of the hand4 ,indeed1 it may be   
doubted whether our utilitarian age can 
ever successfully compete with those    
elder days of art when    ,builders     
wrought with greatest care   ,each      
minute and unseen part4  ,but1 if our   
industrial schools do not make better   
mechanics than the workshops of the     
olden time1 they certainly educate      
better men1 and1 by adding to skill1    
knowledge1 they are elevating the       
mechanic and ennobling his calling4     
,if1 therefore1 these schools are the   
representatives in our age of the       
workshops with their bands of           
apprentices in the days of yore1 then   

that by which the schools are           
distinguished1 that which they have     
added to the old system1 is not art but 
mental culture2 and therefore1 when     
asked to address you on this occasion1  
,i could think of no more appropriate   
subject than the ,nobility of           
,knowledge4  ,identified with an        
institution in which mental culture is  
the chief aim1 ,i felt that ,i was asked
 to address a body of cultivated        
working-men with whom1 though employed  
in the mechanic arts1 the acquisition of
 knowledge was also a privilege and a   
pride4 ,i felt1 moreover1 that a proper 
appreciation of the true dignity of     
knowledge1 in itself considered1 and    
apart from all economical               
considerations1 is one of the great     
wants of our age and of our country4    
,knowledge is power4 ,knowledge is      
wealth4 ,these trite maxims are         
sufficiently esteemed in our community1 
and need not that they be enforced by   
any one4 ,so far as knowledge will yield

 immediate distinction or gain1 it is   
sought and fostered by multitudes4 ,but1
 when the aim is low1 the attainment is 
low1 and too many of our students are   
satisfied with superficiality1 if it    
only glitters1 and with charlatanry1 if 
it only brings gold4  ,let me not be    
understood to depreciate the material   
advantages of learning4 ,i rejoice that 
in this world knowledge frequently      
yields wealth and fame1 and ,i should   
have little hope for human progress were
 the prizes of scholarship less than    
they are4 ,power and wealth are noble   
aims1 and when rightly used may be the  
means of conferring unmeasured blessings
 on mankind2 but ,i desire at this time 
to impress upon you1 my friends1 the    
fact that knowledge has nobler fruits   
than these1 and that the worth of your  
knowledge is to be measured not by the  
credits it will add to your account in  
the ledger1 or the position it may give 
you among men1 but by the extent to     
which it educates your higher nature1   

and elevates you in the scale of        
manhood4  ,i address young men who are  
just entering on life1 who are at an age
 when the mystery of our being usually  
presses most closely upon the soul1 and 
whose aspirations for higher culture and
 clearer vision have not been deadened  
by the sordid damps of the world4 ,trust
 no croakers who tell you that your     
youthful visions are illusions1 which a 
little contact with the real business of
 the world will dispel4  ,it is only too
 true that these visions will become    
fainter and fainter1 if you allow the   
cares of the world to engross your      
thoughts2 but1 unless your higher nature
 becomes wholly deadened1 you will look 
back to the time when the visions were  
brightest1 as the golden period of your 
life1 and let me assure you that1 if you
 only are true to the aspirations of    
your youth1 the visions will become     
clearer and clearer to the last1 and1 as
 we firmly believe1 will prove to be the
 dawn of the perfect day4  ,my friends1 

if you have seen these visions1 the     
nobility of knowledge has been a reality
 of your experience4 ,you know that     
there is a life lived in communion with 
the thoughts of great men or with the   
thoughts of ,god as we can read them in 
,nature and ,revelation1 which is purer 
and nobler than a life of money-making  
or political intrigue1 and ,i would that
 ,i could so bring you to appreciate not
 only the nobility1 but also the        
happiness1 of such a life as to induce  
you to try to live it4  ,do you tell me 
that it is only granted to a few men to 
become scholars1 and that you have been 
educated for some industrial pursuit8   
,remember1 as ,i said before1 that it is
 your special privilege to have been    
educated1 to have added knowledge to    
your handicraft1 and that this very     
knowledge1 if kept alive so far as you  
are able1 will ennoble your life4       
,knowledge1 like the fairy's wand1      
ennobles whatever it touches4 ,the      
humblest occupations are adorned by it1 

and without it the most exalted         
positions appear to true men mean and   
low4  ,nor is it the extent of the      
knowledge alone which ennobles1 but much
 more the spirit and aim with which it  
is cultivated1 and that spirit and aim  
you may carry into any occupation1      
however engrossing1 and into any        
condition of life1 however obscure4     
,and let me add that what ,i have said  
is true not only of the individual1 but 
also1 and to an even greater degree1 of 
the nation4 ,our people1 for the most   
part1 look upon universities and other  
higher institutions of learning as      
merely schools for recruiting the       
learned professions1 and estimate their 
efficiency solely by the amount of      
teaching work which they perform4 ,but1 
however important the teaching function 
of the university may be1 ,i need not   
tell you that this is not its only or   
chief value to a community4 ,the        
university should be the center of      
scientific investigation and literary   

culture1 the nursery of lofty           
aspirations and noble thoughts1 and thus
 should become the soul of the higher   
life of the nation4 ,for this and this  
chiefly it should be sustained and      
honored1 and no cost and no sacrifice   
can be too great which are required to  
maintain its efficiency2 and its success
 should be measured by the amount of    
knowledge it produces rather than by the
 amount of instruction it imparts4      
,harvard ,college1 by cherishing and    
honoring the great naturalist she has   
recently lost1 has done more for        
,massachusetts than by educating hosts  
of commonplace professional men4 ,the   
simple title of teacher1 which in his   
last will ,louis ,agassiz wrote after   
his name1 was a nobler distinction than 
any earthly authority could confer2 but 
remember he was a teacher not of boys1  
but of men1 and his influence depended  
not on the instruction in natural       
history which he gave in his            
lecture-room1 but on his great          

discoveries1 his far-reaching           
generalization1 and his noble thoughts4 
,although that man died poor1 as the    
world counts poverty1 yet the bequest   
which he left to this people can not be 
estimated in coin4  ,it is a sorry      
confession to make1 but it is           
nevertheless the truth1 that1 if we     
compare our ,american universities1 in  
point of literary or scientific         
productiveness1 with those of the ,old  
,world1 they will appear lamentably     
deficient4 ,let me add1 however1 that   
this deficiency arises not from any want
 of proper aims in our scholars1 but    
simply from the circumstance that our   
people do not sufficiently appreciate   
the value of the higher forms of        
literary and scientific work to bear the
 burden which the production necessary  
entails4 ,scholars must live1 as well as
 other men1 and in a style which is in  
harmony with their surroundings and     
cultivated tastes1 and their best       
efforts can not be devoted to the       

extension of knowledge unless they are  
relieved from anxiety in regard to their
 daily bread4  ,in our colleges the     
professors are paid for teaching and for
 teaching only1 while in a foreign      
university the teaching is wholly       
secondary1 and the professor is expected
 to announce in his lectures the results
 of his own study1 and not the thoughts 
of other men4 ,until the whole status of
 the professors in our chief            
universities can be changed1 very little
 original thought or investigation can  
be expected1 and these institutions can 
not become what they should be1 the soul
 of the higher life of the nation4  ,it 
is in your power1 however1 to bring     
about this change1 but the reform can be
 effected in only one way4 ,you must    
give to your universities the means of  
supporting fully and generously those   
men of genius who have shown themselves 
capable of extending the boundaries of  
human knowledge1 and demand of them1    
only1 that they devote their lives to   

study and research1 and let me assure   
you that no money can be spent which    
will yield a larger or more valuable    
return4  ,if you do not look beyond your
 material interests1 the higher life of 
the nation1 which you will thus serve to
 cherish and foster1 will guard your    
honor and protect your home2 and1 on the
 other hand1 what can you expect in a   
nation whose highest ideal is the dollar
 or what the dollar will buy1 but       
venality1 corruption1 and ultimate ruin8
  ,but1 rising at once to the noblest   
considerations1 and regarding only the  
welfare of your country and the         
education of your race1 what higher     
service can you render than by          
sustaining and cherishing the grandest  
thought1 the purest ideals1 and the     
loftiest aspirations which humanity has 
reached1 and making your universities   
the altars where the holy fire shall be 
kept ever burning bright and warm8  ,do 
you think me an enthusiast8 ,look back  
through history1 and see for yourselves 

what has made the nations great and     
glorious4 ,why is it that1 after twenty 
centuries1 the memory of ancient ,greece
 is still enshrined among the most      
cherished traditions of our race8 ,is it
 not because ,homer sang1 ,phidias      
wrought1 and ,plato1 ,aristotle1        
,demosthenes1 ,thucydides1 with a host  
of others1 thought and wrote8 ,or1 if   
for you the military exploits of that   
classic age have the greater charm1 do  
not forget that were it not for ,grecian
 literature1 ,thermopylae1 ,marathon1   
and ,salamis would have been long since 
forgotten1 and that the bravery1        
self-devotion1 and patriotism which     
these names embalm were the direct      
fruits of that higher life which those  
great thinkers illustrated and          
sustained4  ,and1 coming down to modern 
times1 what are the shrines in our      
mother country which we chiefly         
venerate1 and to which the transatlantic
 pilgrim oftenest directs his steps8 ,is
 it her battlefields1 her castles and   

baronial halls1 or such spots as        
,stratford-on-,avon1 ,abbotsford1 and   
,rydal ,mount8 ,why1 then1 will we not  
learn the lesson which history so       
plainly teaches1 and strive for those   
achievements in knowledge and mental    
culture which will be remembered with   
gratitude when all local distinctions   
and political differences shall have    
passed away and been forgotten8  ,while 
,i was considering the line of discourse
 which ,i should follow on this         
occasion1 an incident occurred          
suggesting an historical parallel1 which
 will illustrate1 better than any       
reflections of mine1 the truth ,i would 
enforce4 ,the ship ,faraday arrived on  
our coast after laying over the bed of  
the ,atlantic another of those electric 
nerves through which pulsate the        
thoughts of two continents1 and as ,i   
read the description of that noble ship1
 fitted out with all the appliances     
which modern science had created to     
insure the successful accomplishment of 

the enterprise1 ,i remembered that not a
 century had elapsed since the first    
obscure phenomena were observed1 whose  
conscientious study1 pursued with the   
unselfish spirit of the scientific      
investigator1 had led to these momentous
 results1 and my imagination carried me 
back to an autumn day of the year #aghf1
 in the old city of ,bologna1 in ,italy1
 and ,i seemed to assist at the         
memorable experiment which has          
associated the name of ,aloysius        
,galvani with that mode of electrical   
energy which flashes through the wire   
cords that now unite the four quarters  
of the globe4  ,galvani is ,professor of
 ,anatomy in the ,university of         
,bologna1 and there is hanging from the 
iron balcony of his house a small animal
 preparation1 which is not an unfamiliar
 sight in ,southern ,europe1 where it is
 regarded as a delicacy of the table4   
,it is the hind-legs of a frog1 from    
which the skin had been removed1 and the
 great nerve of the back exposed4 ,six  

years before1 his attention had been    
called to the fact that the muscles of  
the frog were convulsed by the indirect 
action of an electrical machine1 under  
conditions which he had found very      
difficult to interpret4 ,he had         
connected the phenomenon with a theory  
of his own3 that electricity--that is1  
common friction electricity1 the only   
mode of electrical action then          
known--was the medium of all nervous    
action2 and this had led him into a     
protracted investigation of the subject1
 during which he had varied the original
 experiment in a thousand ways1 and he  
had now suspended the frog's legs to the
 iron balcony1 in order to discover if  
atmospheric electricity would have any  
effect on the muscles of the animal4    
,galvani has spent a long day in        
fruitless watching1 when1 while holding 
in his hand a brass wire1 connected with
 the muscles of the frog1 he rubs the   
end1 apparently listlessly1 against the 
iron railing1 when1 lo6 the frog's legs 

are convulsed4  ,the patient waiting had
 been rewarded1 for this observation was
 the beginning of a line of discovery   
which was ere long to revolutionize the 
world4 ,but ,galvani was not destined to
 follow far the new path he had thus    
opened4 ,the remarkable fact observed   
was this3 ,the convulsions of the frog's
 legs could be produced without the     
intervention of electricity1 or1 at     
least1 of the one kind of electricity   
then known1 and ,galvani soon found out 
that the only condition necessary to    
produce the result was1 that the nerve  
of the frog should be connected with the
 muscle of the leg by some good         
electrical conductor4  ,but1 although   
,galvani followed up this observation   
with the greatest zeal1 and showed      
remarkable sagacity throughout his whole
 investigation1 yet he was too strongly 
wedded to his own theory to interpret   
correctly the facts he observed4 ,he    
supposed1 to the end of his life1 that  
the whole effect was caused by animal   

electricity flowing through the         
conductor from the nerve to the muscle1 
and his experiments were chiefly        
interesting to himself and to his       
contemporaries from the light they were 
supposed to throw on the mysterious     
principle of life4 ,we now know that    
animal electricity played only a small  
part in the phenomena he observed1 and  
that the chief effects were due to a    
cause of which he was wholly ignorant4  
,galvani published his observations in  
#agia1 in a monograph entitled ,the     
,action of ,electricity in ,muscular    
,motion4 ,this publication excited the  
most marked attention1 and1 within a    
year1 all ,europe was experimenting on  
frogs' legs4 ,the phenomena were        
everywhere reproduced1 but ,galvani's   
explanation of the phenomena was by no  
means so universally accepted4 ,his     
theory was controverted in many         
quarters1 and by no one more            
successfully than by ,alexander ,volta1 
,professor of ,physics in the           

neighboring ,university of ,pavia4      
,volta1 while admitting1 with ,galvani1 
that the muscular contractions were     
caused by electricity1 explained the    
origin of the electricity in a wholly   
different way4 ,according to ,volta1 the
 electricity originated not in the      
animal1 but in the contact of the       
dissimilar metals or other materials    
used in the experiment4 ,this difference
 of opinion led to one of the most      
remarkable controversies in the history 
of science1 and for six years1 until his
 death in #agih1 ,galvani was occupied  
in defending his theory of animal       
electricity against the assaults of his 
distinguished countryman4  ,this        
discussion created the liveliest        
interest throughout ,europe4 ,every     
scholar of science took sides with one  
or the other of these eminent ,italian  
philosophers1 and the scientific world  
became divided into the school of       
,galvani and the school of ,volta4 ,yet1
 so far at least as the fundamental     

experiment was concerned1 both were     
wrong4 ,the electricity came neither    
from the body of the frog nor from the  
contact of dissimilar kinds of matter1  
but was the result of chemical action1  
which both had equally overlooked4      
,but1 nevertheless1 the controversy led 
to the most important results3 for      
,volta1 while endeavoring to sustain his
 false theory by experimental proofs1   
was led to the discovery of the ,voltaic
 pile1 or1 as we now call it1 the       
,voltaic battery1 an instrument whose   
influence on civilization can be        
compared only with the printing-press   
and the steam-engine4 ,yet1 although the
 whole action of the battery was in     
direct contradiction to his pet theory1 
still1 to the last1 ,volta persistently 
defended the erroneous doctrine he had  
espoused in his controversy with        
,galvani thirty years before1 and he    
died in #ahbg1 without realizing how    
great a boon he had been instrumental in
 conferring on mankind2 so true it is   

that ,providence works out his bright   
designs even through the blindness and  
mistakes of man4  ,but there is another 
lesson to be learned from this history1 
which can not be too often rehearsed in 
this self-sufficient age1 which boasts  
so proudly of its practical wisdom4     
,there were1 doubtless1 many practical  
men in that city of ,bologna to smile at
 their sage professor1 who had spent ten
 long years in studying1 to little      
apparent purpose1 the twitchings of     
frogs' hind-legs1 and there was many a  
jest among the courtiers of ,europe at  
the expense of the learned philosophers 
who wasted so much time in discussing   
the cause of such trivial phenomena4    
,but how is it now8  ,less than a       
century has passed since ,galvani's     
death1 and in a small hut on the shores 
of ,valentia ,bay may be seen one of the
 most skillful of a new class of        
practical men1 representing a profession
 which owes its origin to ,galvani and  
,volta4 ,the electrician is watching a  

spot of light on the scale of an        
instrument which is called a            
galvanometer4 ,since the fathers fell   
asleep1 the field of knowledge which    
they first entered has spread out wider 
and wider before the untiring explorers 
who have succeeded them4 ,oersted and   
,seebeck1 ,arago and ,ampere1 ,faraday  
and our own ,henry1 have made wonderful 
discoveries in that field2 and other    
great men1 like ,steinheil1 ,wheatstone1
 ,morse1 and ,thomson1 have invented    
ingenious instruments and appliances1 by
 which these discoveries might be made  
to yield great practical results4  ,the 
spot of light1 which the electrician is 
watching1 is reflected from one of the  
latest of these inventions1 the         
reflecting galvanometer of ,thomson4 ,he
 and his assistants had been watching by
 turns the same spot for several days1  
since the ,great ,eastern had steamed   
from the bay1 paying out a cable of     
insulated wire4 ,these electricians had 
no anxiety as to the result1 for daily  

signals had been exchanged between the  
ship and the shore1 as hundreds after   
hundreds of miles of this electrical    
conductor had been laid on the bed of   
the broad ocean4 ,the coast of          
,newfoundland had already been reached1 
and they were only waiting for the      
landing of the cable at the now         
far-distant end4  ,at length the light  
quivers1 and the spot begins to move4   
,it answers to concerted signals4 ,and  
soon the operator spells out the joyful 
message4 ,the ocean has been spanned    
with an electric nerve1 and the ,new    
,world responds to the greetings of the 
,old4  ,here is something practical1    
which all can appreciate1 and all are   
ready to honor4 ,we honor the courage   
which conceived1 the skill which        
executed1 and1 above all1 the success   
which crowned the undertaking4 ,but do  
we not forget that professor of         
,bologna1 with his frogs' legs1 who     
sowed the seed from which all this has  
sprung8 ,he labored without hope of     

temporal reward1 stimulated by the pure 
love of truth1 and the grain which he   
planted has brought forth this abundant 
harvest4 ,do we not forget1 also1 that  
succession of equally noble men1 ,volta1
 and ,oersted1 and ,faraday1 with many  
other not less devoted investigators of 
electrical science1 without whose       
unselfish labors the great result never 
could have been achieved8 ,such men1 of 
course1 need no recognition at our      
hands1 and ,i ask the question not for  
their sakes1 but for ours4 ,the         
intellectual elevation of the lives they
 led was their all-sufficient reward4   
,it is1 however1 of the utmost          
importance for us1 citizens of a country
 with almost unlimited resources1 that  
we should recognize what are the real   
springs of true national greatness and  
enduring influence4 ,in this age of     
material interests1 the hand is too     
ready to say to the head1 ,i have no    
need of thee2 and1 amid the ephemeral   
applause which follows the realization  

of some triumph over matter1 we are apt 
to be deceived1 and not observe whence  
the power came4 ,we associate the great 
invention with some man of affairs man  
who overcame the last material obstacle1
 and who1 although worthy of all praise1
 probably added very little to the total
 wealth of knowledge of which the       
invention was an immediate consequence2 
and1 not seeing the antecedents1 we are 
apt to underrate the part which the     
student or scientific investigator may  
have contributed to the result4  ,it is 
idle1 for example1 to speak of the      
electric telegraph as invented by any   
single man4 ,it was a growth of time1   
and many of the men who contributed to  
win this great victory of mind over     
space builded far better than they knew4
 ,as ,i view the subject1 that invention
 is as much a gift of ,providence as if 
the details had been supernaturally     
revealed4 ,but1 whatever may be our     
speculative views1 it is of the utmost  
importance to the welfare of our        

community that we should realize the    
fact that purely theoretical scientific 
study1 pursued for truth's sake1 is the 
essential prerequisite for such         
inventions4 ,knowledge is the condition 
of invention4 ,the old ,latin word      
invenio signifies to meet with1 as well 
as to find1 and these great gifts of    
,god are met with along the pathway of  
civilization2 but the throng of the     
world passes them unnoticed1 for only   
those can recognize the treasure whose  
minds have been stored with the         
knowledge which the scholar has         
discovered and made known4  ,if1 then1  
as no one will deny1 science and        
scholarship are the powers by which     
improvements in the useful arts are     
made1 ,i might appeal to your           
self-interest to support and cherish    
them4 ,but ,i should despise myself for 
appealing to such a motive1 and you for 
requiring it4 ,the supreme importance of
 science and scholarship to a nation    
does not depend in the least on the     

circumstance that important practical   
results may follow4 ,when1 as in the    
case of ,galvani's frogs1 they come in  
the order of ,providence1 let us thank  
,god for them as a gift which we had no 
right either to expect or demand4       
,science1 if studied successfully1 must 
be studied for the pure love of truth2  
and1 if we serve her solely for         
mercenary ends1 her truths1 the only    
gold she offers1 will turn to dross in  
our hands1 and we shall degrade         
ourselves in proportion as we dishonor  
her4  ,galvani1 and ,volta1 and         
,oersted1 who discovered the truths of  
which the electric telegraph is a simple
 application1 sure to be made as soon as
 the time was ripe1 are not the less to 
be honored because they died before the 
fullness of that time had come4 ,we     
honor them for the truths they          
discovered1 and the lustre of their     
consecrated lives could be neither      
enhanced nor impaired by subsequent     
events2 and it is because ,i am         

persuaded that such lives are the salt  
of the world1 the saviours of society1  
that ,i would lead you to cherish and   
sustain them2 and1 that ,i may enforce  
this conclusion1 allow me to ask your   
attention to another historical         
incident1 which presents a striking     
parallelism to the last4  ,i must take  
you back to a period which we1 of a     
nation born but yesterday1 regard as    
distant1 but which was one of the most  
noted epochs of modern history--the age 
of ,luther and the ,reformation4 ,i must
 ask you to accompany me to the small   
town of ,allenstein1 near ,frauenberg1  
in ,eastern ,prussia1 where1 on ,may    
#bc1 #aedc1 there lay dying one of the  
great benefactors of mankind4  ,this    
man1 old at seventy years1 bent and     
furrowed with labor1 but in whose eye   
the fire of genius was still glowing1   
was then known as one of the most       
learned men of his time4 ,doctor of     
medicine as well as of theology1 ,canon 
of ,frauenberg1 ,honorary ,professor of 

,bologna and ,rome1 while devoting his  
leisure to study1 he had passed a life  
of active benevolence in administering  
to the bodily as well as the spiritual  
wants of the ignorant people among whom 
his lot had been cast4 ,he was also a   
great mechanical genius1 and1 by various
 labor-saving machines1 of his own      
invention1 he had contributed greatly to
 the welfare of the surrounding country4
  ,but the superstitious peasants1      
although they had hitherto reverenced   
the great man as their best friend and  
benefactor1 had been recently incited by
 his enemies and rivals in the church to
 curse him as a heretic and a wizard4 ,a
 few days back he had been the unwilling
 witness of one of those out-of-door    
spectacles1 so common at that time1 in  
which his scientific opinions had been  
travestied1 his charities ridiculed1 and
 his devoted life made the object of    
slander and reproach4 ,this ingratitude 
of his flock had broken his heart1 and  
he could not recover from the blow4     

,the occasion of this outburst of       
fanaticism was the approaching          
publication of a work in which he had   
dared to question the received opinions 
of theologians and schoolmen1 in regard 
to cosmogony4 ,he had1 forsooth1 denied 
that the visible firmament was a solid  
azure-colored shell1 to which the sun   
and planets were fastened1 and through  
whose opened doors the rain descended4  
,he had proved that the sun was the     
center of the system1 around which the  
earth and planets revolved1 and1 with   
his clear scientific vision1 he had been
 able to gain glimpses1 at least1 of the
 grand conceptions of modern astronomy3 
,for this man was ,nicolas ,copernicus1 
and the expected book was his great     
work--,de ,orbium ,coelestium           
,revolutionibus--destined to form the   
broad basis of astronomical science4    
,the work was printing at ,nuremberg1   
and the last proofs had been returned2  
but reports had come that a similar     
outburst of fanaticism was raging at    

that place1 that a mob had burned the   
manuscript on the public square1 and had
 threatened to break the press should   
the printing proceed4 ,but1 thanks to   
,god6 the old man was not to die before 
the hour of triumph came4 ,while still  
conscious1 a horse1 covered with foam1  
gallops to the door of his humble       
dwelling1 and an armed messenger enters 
the chamber1 who1 breathless with haste1
 places in the hands of the dying man a 
volume still wet from the press4 ,he has
 only strength to return a smile of     
recognition1 and murmur the last words3 
,nunc dimittis servum tuum1 ,domine4    
,grand close of a noble life6 ,the seed 
has been sown--what could we desire     
more8  ,again the centuries roll on--not
 one1 but three--while the seed grows to
 a great tree1 which overshadows the    
nations4 ,great minds have never been   
wanting to cherish and prime it1 like   
,tycho ,brahe and ,kepler1 ,galileo and 
,newton1 ,laplace and ,lagrange2 and    
although at times some1 while lingering 

in the deep shade of the foliage1 may   
have lost sight of the summit1 the noble
 tree has ever pointed upward to direct 
aspiration and encourage hope4  ,on the 
evening of the #bdth of ,september1     
#ahdf1 in the ,observatory of ,berlin1 a
 trained astronomical observer was      
carefully measuring the position of a   
faint star in the constellation         
,capricorn4 ,only the day before1 he had
 received from ,le ,verrier a letter    
announcing the result of that remarkable
 investigation which has made the name  
of this distinguished ,french astronomer
 so justly celebrated4 ,by the studies  
of the great men who succeeded          
,copernicus1 his system had become so   
perfected as to enable the astronomer to
 predict1 with unerring certainty1 the  
paths of the planets through the        
heavens4 ,but there was one failing     
case4 ,the planet ,uranus1 then supposed
 to be the outer planet of the solar    
system1 wandered from the path which    
theory assigned to it2 and although the 

deviations were but small1 yet any      
discrepancy between theory and          
observation in so accurate a science as 
astronomy could not be overlooked4      
,long before this1 the hypothesis had   
been advanced that the deviations were  
caused by the attractive force of an    
unseen and still more distant planet2   
but1 as no such planet had been         
discovered1 the hypothesis had remained 
until now wholly barren4 ,the           
hypothesis1 however1 was reasonable1 and
 furnished the only conceivable         
explanation of the facts2 and1 moreover1
 if true1 the received system of        
astronomy ought to be able to assign the
 position and magnitude of the          
disturbing body1 the magnitude and      
direction of the displacements being    
given4  ,this possibility was generally 
appreciated by astronomers1 and the very
 great length and difficulty of the     
mathematical calculation which the      
investigation involved was probably the 
reason that no one had hitherto         

undertaken it4 ,le ,verrier1 however1   
had both the courage and the youthful   
strength required for the work4 ,and now
 the great work had been done2 and1 on  
the #ahth of ,september1 ,le ,verrier   
had sent to the ,observatory of ,berlin 
his communication announcing the final  
result1 namely1 that the planet would be
 found about #e deg4 to the east of the 
star ,delta of ,capricorn4  ,the letter 
containing this announcement was        
received by ,galle1 at ,berlin1 on the  
#bc;d1 and it was ,galle whom we left   
measuring the position of that faint    
star on the evening of the #bdth4 ,it so
 happened that a chart of that portion  
of the heavens had recently been        
prepared by the ,berlin ,observatory1   
and was on the eve of publication2 and1 
on the very evening he received the     
letter1 ,galle had found1 near the      
position assigned by ,le ,verrier1 a    
faint star1 which was not marked on this
 chart4 ,the object differed in         
appearance from the surrounding stars1  

but still it was perfectly possible that
 it might be a fixed star which had     
escaped previous observation4  ,but1 if 
a fixed star1 its position in the       
constellation would not vary1 while1 if 
a planet1 a single night would show a   
perceptible change of place4 ,hence1 you
 may conceive of the interest with which
 ,galle was measuring anew its position 
on the evening of the #bdth4  ,the star 
had moved1 and in the direction which   
theory indicated2 and for once1 at      
least1 the world rang with applause at a
 brilliant scientific conquest from     
which there was not one cent of money to
 be made4 ,yet1 was that conquest any   
less important to the world8 ,what had  
it secured8 ,it had confirmed the theory
 of astronomy which ,copernicus and his 
successors had built up1 and it had     
clinched the last nail in the proof that
 those grand conceptions of modern      
astronomy1 now household thoughts1 are  
realities1 and not dreams4 ,certainly no
 military conquest can compare with     

this4  ,do not smile at the enthusiasm  
which rates so high a purely            
intellectual achievement8 ,go out with  
me under the heavens1 in some starlight 
night1 and1 looking up into the depths  
of space1 recall the truths you have    
learned in regard to that immensity1 and
 allow the imagination free scope as it 
stretches out into the infinitudes of   
time1 space1 and power1 carrying the    
mind on1 bound by bound1 through the    
limitless expanse1 until even the       
imagination refuses to follow1 and      
fairly quails before the mighty form of 
the ,infinite1 which rises to confront  
it6 ,remember now that your forefathers1
 of only a few centuries back1 saw there
 nothing but a solid dome hemming in the
 earth and skies1 and that you are able 
to look upon this grand spectacle only  
because great minds have lived who have 
opened your intellectual eyes2 and then 
answer me1 is not this result worth all 
the labor1 all the sacrifice1 all the   
treasure it has cost8  ,every educated  

man1 who has not sold his birthright for
 a mess of pottage1 lives a grander and 
nobler life1 because the great          
astronomers have thought and taught1 and
 this elevation of human life is the    
greatest achievement of which man can   
boast4 ,before it all material conquests
 appear of little worth1 and the lustre 
of all military or civil glory grows    
dim4 ,cherish this intellectual life2   
foster it2 sustain it2 do what you can  
by your own spirit and influence1 and1  
if you are blessed with riches1 give of 
your abundance to support and encourage 
those who1 by genius1 talent1 and       
devotion1 will widen the intellectual   
kingdom4 ,be assured you will thus help 
to confer an inestimable boon on your   
race and on your country2 and the       
influence for good will not be felt by  
the intellectual life of the nation     
only4 ,that corruption which is now     
festering at the heart of our body      
politic1 and threatening its            
destruction1 can in no way be fought and

 conquered so effectually as by keeping 
constantly before the nation noble and  
high ideals2 for1 where the higher life 
is cherished and honored1 the mercenary 
and sensual motives of action1 which    
both invite and shield corruption1 lose 
much of their force and power4  ,but you
 may tell me that there is a life higher
 than the intellectual life1 and that ,i
 have ascribed to science and           
scholarship influences which come only  
from a source which ,i have forgotten1  
or left out of view4 ,my friends1 all   
truth is one and inseparable1 and ,i    
have therefore made no distinction in   
this address between the truths of      
science and truths of religion4 ,the    
grand old word knowledge1 as ,i have    
used it1 includes both1 and1 in just the
 proportion that you reverence religion1
 you must reverence also true science4  
,all truth is ,god's truth1 and1 in     
praying for the coming of his kingdom1  
you certainly do not expect that ,nature
 will be divorced from ,grace4 ,if the  

truths of religion required a special   
revelation1 it must be expected that    
they would transcend human intelligence4
 ,these very conditions imply conflict1 
but the conflict comes not from the     
knowledge1 but from the ignorance and   
conceit of men2 and the only proper     
attitude for the devout scholar is to   
labor and to wait4 ,and what more       
wonderful confirmation could we have of 
the essential unity of the two phases of
 truth than is to be found in the fact  
that the characteristic of science1     
which ,i have been endeavoring to       
illustrate in this address1 is the great
 prominent feature of ,christianity8    
,christianity was revealed in a life1   
and ever abides a life in the soul of   
man1 to purify1 ennoble1 and redeem     
humanity4    ,and so the ,word had      
breath1 and wrought1       ,with human  
hands1 the creed of creeds1       ,in   
loveliness of perfect deeds1   ,more    
strong than all poetic thought--        
,which he may read that binds the sheaf1

       ,or builds the house1 or digs the
 grave1       ,and those wild eyes that 
watch the wave1   ,in roarings round the
 coral reef4     ,,iii4  ,,the          
,,elementary ,,teaching ,,of ,,physical 
,,science4      ,an ,address to the     
,schoolmasters of ,boston1 delivered    
,february #d1 #ahgh4   ,i felt a great  
reluctance at accepting the invitation  
of your excellent superintendent to     
address you on this occasion2 for1      
although ,i could claim an unusually    
long experience in presenting the       
elements of physical science to college 
students1 ,i was fully conscious that ,i
 knew little of the conditions under    
which such subjects must be studied1 if 
at all1 in the elementary schools1 and  
was therefore in danger of appearing in 
a capacity which ,i should most         
sedulously shun1 that of a babbler about
 impracticable theories of education4   
,it is very easy to criticize another   
man's labor1 and such criticisms1       
however plausible1 do the grossest      

injustice when1 as is often the case1   
they leave out of view the necessary    
conditions and limitations under which  
the work must be done4 ,while1 however1 
,i felt most keenly my incapacity to    
deal with many of the practical problems
 which you have to solve1 yet1 on       
consideration1 ,i concluded that it was 
my duty under the circumstances to state
 as clearly and forcibly as ,i could the
 very definite opinions which ,i had    
formed on the subject you are           
discussing1 knowing that you will only  
give such weight to these opinions as   
your mature judgment can allow4 ,in     
stating the results of my experience1 ,i
 can not avoid a certain personal       
element1 which would be wholly          
inexcusable were it not that the facts1 
as ,i think you will admit1 form the    
basis of my argument4  ,i am a ,boston  
boy1 born in this immediate             
neighborhood1 and fitted for college at 
the ,latin ,school4 ,it so happened     
that1 while ,i was very unsuccessfully  

endeavoring to commit to memory1 in the 
old school-house on ,school ,street1    
,andrews and ,stoddard's ,latin grammar1
 not one word of which ,i could         
understand1 the ,lowell ,institute      
lectures were opened at the ,odeon on   
,congress ,street4 ,at those lectures ,i
 got my first taste of real knowledge1  
and that taste awakened an appetite     
which has never yet been satisfied4 ,as 
a boy1 ,i eagerly sought the small      
amount of popular science which the     
,english literature of that day         
afforded2 and ,i can now distinctly     
recall almost every page of ,mrs4       
,marcet's ,conversations on ,chemistry1 
which was the first book on my science  
that ,i ever read4 ,more to the point   
than this1 a boy's pertinacity1 favored 
by a kind father's indulgence1 found the
 means of repeating1 in a small way1    
most of the experiments first seen at   
the ,lowell ,institute lecture2 and thus
 it came to pass that1 before ,i entered
 college1 ,i had acquired a real1       

available knowledge of the facts of     
chemistry2 although1 with much labor and
 intense weariness1 ,i had gained only a
 formal knowledge of those subjects     
which were then regarded as the only    
essential preparation for the college   
course4 ,in college1 my attention was   
almost exclusively devoted to other     
studies--for1 in my day at ,cambridge1  
chemistry was one of the lost arts4 ,but
 when1 the year after ,i graduated1 ,i  
was most unexpectedly called upon to    
give my first course of lectures1 the   
only laboratory in which ,i had worked  
was the shed of my father's house on    
,winthrop ,place1 and the only apparatus
 at my command was what this boy's      
laboratory contained4 ,with these simple
 tools1 or1 as ,i should rather say1    
because they were so simple1 ,i gained  
that measure of success which determined
 my subsequent career4  ,i feel that ,i 
owe you a constant apology for these    
personal details1 and ,i should not be  
guilty of them did ,i not believe that  

they establish two points more          
conclusively than ,i could prove them in
 any other way4 ,first1 that it is      
perfectly possible for a child before   
fifteen years of age to acquire a real  
and living knowledge of the fundamental 
facts of nature on which physical       
science is based4 ,secondly1 that this  
knowledge can be effectually gained by  
the use of the simplest tools4 ,let me  
add that this is not a question of      
natural endowments or special aptitudes1
 for every one who has studied from the 
love of knowledge has had the same      
experience2 and ,i do not believe that1 
if my first taste of real knowledge had 
been of history1 nay1 ,i will even say1 
of philology1 instead of chemistry1 the 
circumstance would have materially      
influenced my success in life1 however  
different the direction into which it   
might have turned my study4 ,my early   
tastes were utterly at variance with all
 my surroundings and all my             
inheritances1 and were simply determined

 by the accident which first satisfied  
that natural thirst for knowledge which 
every child experiences to a greater or 
less degree--a desire most rudely       
repressed in our usual methods of       
teaching4  ,my bitter experience as a   
pupil in the ,boston ,latin ,school and 
my subsequent more fortunate experience 
of thirty years as a teacher in ,harvard
 ,college have impressed me most        
profoundly with the conviction that the 
only way to arouse and sustain a love   
for knowledge in children is to         
cultivate their perceptive faculties4   
,to present the rudiments of knowledge  
to immature minds in an abstract form1  
whether the subject be grammar or       
physical science1 is1 in my judgment1   
not only culpable folly1 but also       
downright wrong4 ,and1 if1 to those who 
have been accustomed to the long        
established routine of our public       
school1 my opinions may appear          
revolutionary and extreme1 ,i am1       
nevertheless1 sure that they would      

receive the universal assent of the men 
whom all would recognize as the foremost
 scientific teachers of the world4 ,i   
can well remember that when1 many years 
ago1 the late ,professor ,agassiz       
declared in my hearing that he would    
have no text-books used in his museum1  
,i thought his plan of pure             
object-teaching chimerical in the       
extreme1 and yet experience has not only
 convinced me of the wisdom of his      
judgment in regard to the teaching of   
natural history1 but brought me to a    
similar conclusion in regard to the     
elementary teaching both of natural     
philosophy and of chemistry4  ,allow me 
then to express my firm persuasion that 
it is not only useless but injurious to 
the education of young minds to present 
to them at the outset any department of 
physical science as a body of           
definitions1 principles1 laws1 or       
theories2 and that in elementary schools
 only such facts should be taught as can
 be verified by the experience of the   

pupil1 or by such simple experiments as 
the pupils can try for themselves4 ,the 
usual method of committing by heart the 
words of a school-book1 and repeating   
them at the dictation of a teacher1 may 
afford a good exercise for the memory1  
but it is absurd to regard such a task  
as a lesson in physical science1 and    
this kind of study can be spent with    
vastly greater profit on the            
spelling-book4  ,there is one department
 of physical science which has been     
taught in this absurd way in our schools
 from time immemorial4 ,i refer1 of     
course1 to the study of geography1 and  
,i leave for you to judge whether the   
result is worth the one hundredth part  
of the toil and drudgery spent in       
obtaining it4 ,let us suppose that your 
child is able to give you the names of  
all the rivers1 bays1 and capes from    
,greenland to ,patagonia1 how much more 
does that child know of the structure   
and social relations of this globe on   
which its lot has been cast than it did 

before this senseless feat was          
attempted1 a feat1 moreover1 to which   
only a child's memory would be equal8   
,and1 when you turn to your own         
experience1 what is the outcome of all  
the time and labor spent on geography8  
,is it not solely just that portion of  
your knowledge which1 in spite of the   
system1 was direct object-teaching--the 
images you insensibly acquired from the 
maps and pictures in the school-books8  
,but there is a very different way of   
teaching geography1 by which the study  
may be made a pleasure1 not a task4 ,the
 teacher does not begin with abstract   
definitions of rivers1 and bays1 and    
oceans1 which convey no definite meaning
 to a child1 but with ,charles ,river1  
,boston ,harbor1 and the ,atlantic      
,ocean1 which are to him real things1   
however imperfect his conceptions of    
their extent4 ,the child is first shown1
 not a map of the globe1 which he can   
not by any possibility understand1 but a
 map of a very limited region around his

 own home4 ,he is taught how to find the
 north and south1 the east and west     
directions4 ,he is encouraged to make   
excursions to verify the map1 or to add 
to its details1 and such excursions may 
be made to have for him all the zest of 
voyages of discovery2 and when thus the 
rudiments of geographical science have  
been mastered1 not in technical terms1  
but in substance1 then the teacher may  
begin to expand the horizon of the      
pupil's knowledge1 judiciously omitting 
details in proportion as distance       
increases1 until at length the general  
survey embraces the globe4 ,of course1  
such teaching as this can only be given 
orally with the help of proper          
apparatus1 such as wall maps1 and       
globes1 and photographs4 ,it must take  
the interrogative form1 and the         
questions should be directed to bring   
out the child's already acquired        
knowledge1 and to lead him to observe   
facts which had hitherto escaped his    
notice4 ,what a child reads in a book1  

or even what you tell him1 is never one 
half learnt1 unless his interest is     
aroused4 ,but what a child observes for 
himself he never forgets1 and when you  
have thus aroused his interest you can  
associate a large number of facts with  
one observation1 and these all          
crystallize in his memory around this   
nucleus4  ,this is no mere theory1 no   
untried method which ,i am advocating4  
,so far from it1 ,i am describing the   
precise method which has been used for  
many years in ,germany1 where the       
science of education is far better      
understood than with us1 and where      
economy both of time and labor in       
teaching is most carefully studied4 ,if 
our school committees could attend and  
understand a single exercise in         
geography1 such as are daily given in   
the elementary schools of ,prussia1 ,i  
am sure that at least one form of child 
torture would soon disappear from the   
primary schools of this country4        
,indeed1 ,i already see evidence of a   

growing public opinion on this subject1 
an effect which ,i trace in no small    
measure to the influence of the         
,department of ,education of the        
,exhibition at ,philadelphia in #ahgf4  
,that which is true of geography applies
 with still greater force to such       
subjects as physics and chemistry1 since
 the abstract conceptions which these   
sciences involve are more abstruse1 and 
the language by which the conceptions   
are expressed or defined far less plain 
than is the case with the older and more
 descriptive branch of knowledge4       
,hence1 as sciences1 properly so called1
 that is1 as philosophical systems1 they
 have no place whatever in elementary   
education4 ,but1 underlying these       
systems1 there is a great multitude of  
phenomena which a child can be led to   
observe and apprehend as readily as the 
facts of geography4 ,take that          
subject--mechanics--which our ordinary  
school-books very philosophically but   
most unpractically place at the         

beginning of what they call ,natural    
,philosophy4 ,how many of the           
fundamental facts of this difficult     
subject can be made familiar to a child8
 ,select1 as an example1 ,newton's      
,first ,law of ,motion4 ,suppose you    
make a boy memorize the ordinary rule1  
,every body continues in a state of rest
 or of uniform motion in a straight line
 until acted upon by some external      
force1 how much will he know about it8  
,suppose you make him do a lot of       
problems involving distances1           
velocities1 and times1 will he know any 
more about it8 ,but ask him1 ,can you   
pitch a ball as well as your playmate8  
and he answers at once1 ,no2 ,john is   
stronger than ,i am4 ,and then1 if again
 you ask1 ,can you catch ,john's ball8  
he will probably reply1 ,of course1 not6
 ,it requires a boy as strong as ,john  
to catch his balls4 ,and thus1 by a few 
well-directed questions1 you would bring
 that boy to learn a lesson which he    
would never forget1 and which he would  

recall every time he played base-ball2  
namely1 that ,john's swift balls could  
not be set in motion without an         
expenditure of a definite amount of     
muscular effort1 and could not be       
stopped without the exertion of an equal
 amount of what1 after a while1 you     
could get him to call force4 ,from the  
ball you would naturally pass to the    
railroad train or the steamboat1 and ,i 
should not wonder if1 with a little     
patience1 you could bring even a boy to 
understand that motion can not be       
maintained against a resistance1 in     
other words1 that work can not be done  
without a constant expenditure of       
muscular effort1 or of some other source
 of power2 and it is a fond hope of mine
 that by the time these boys grow into  
men our intelligent ,new ,england       
community might become so far educated  
in the elementary principles of         
mechanics that no self-sustained motors1
 nor other mechanical nostrums which    
claim to have superseded the primeval   

curse--if that law was a curse1 which   
compels man to earn his bread with the  
sweat of his brow--will receive the     
sanction of our respectable journals2   
and then--if they have not previously   
learned the lesson by dire              
experience--we may hope to persuade our 
people of the parallel and equally      
elementary principle of political       
economy1 that value can not be          
legislated into rags4  ,but1 my friends1
 our subject gives no occasion for      
banter1 and presents aspects too serious
 to be treated lightly or in jests4 ,as 
inhabitants of a not over-fruitful land1
 and1 therefore1 members of a community 
which must excel1 if at all1 solely by  
its enterprise and intelligence1 we have
 a duty to our children which we can not
 avoid1 if we would1 and for which we   
shall be held responsible by our        
posterity4 ,these children are entering 
life surrounded not only by all the     
wonders and glories of nature1 but1     
also1 by giant conditions1 which1       

whether stationed on their path as a    
blessing or a curse1 will inevitably    
strike if their behests are not obeyed4 
,so far as science has been able to     
define these giant forms1 it is our     
duty1 as it is our privilege1 to point  
them out to those we are bound to       
protect and guide2 and in many cases it 
is in our power to change the curse into
 a blessing1 and to transform the       
destructive demon into a guardian angel4
 ,after that command of language which  
the necessities of civilized life       
imperatively require1 there is no       
acquisition which we can give our       
children that will exert so important an
 influence on their material welfare as 
a knowledge of the laws of nature1 under
 which they must live and to which they 
must conform2 and throughout whose      
universal dominion the only question is 
whether men shall grovel as ignorant    
slaves or shall rule as intelligent     
servants4 ,yes2 rule by obeying4 ,ich   
,dien2 for only under that motto1 which1

 five hundred years ago1 the great      
,black ,prince bore so victoriously     
through the fields of ,cressy and       
,poitiers1 can man ever rule in         
,nature's kingdom4  ,i regard it1       
therefore1 as the highest duty and the  
most enlightened self-interest of a     
community like this to provide the best 
means for the instruction of its        
children in the elements of physical    
science2 and ,i was1 therefore1 most    
anxious to do all in my power to second 
the enlightened efforts of your eminent 
,superintendent in this direction4 ,you 
must remember1 however1 that the best   
tools are worthless in themselves1 and  
can secure no valuable results unless   
judiciously used4 ,indeed1 there is     
danger in too many tools1 and ,i have a 
great horror of that array of brass-work
 which is usually miscalled             
philosophical apparatus4 ,the greater   
part of this is1 in my opinion1 a mere  
hindrance to the teacher1 because it at 
once erects a barrier between the       

scholar and the simple facts of nature1 
and the child inevitably associates with
 the phenomenon illustrated some        
legerdemain1 and looks on your          
experiments very much as he would on the
 exhibition of a ,houdin or a ,signor   
,blitz4 ,the secret of success in       
teaching physical science is to use the 
simplest and most familiar means to     
illustrate your point4  ,when a very    
young man ,i was favored with an        
introduction to ,michael ,faraday1 and  
had the privilege of attending a portion
 of a course of lectures which this     
noble man was then in the habit of      
giving every ,christmas season to a     
juvenile auditory at the ,royal         
,institution of ,london4 ,as a boy1 ,i  
had become familiar with lectures on    
chemistry at the ,lowell ,institute1    
where they did not lack the pomp of     
circumstance or the display of          
apparatus1 and ,i had come to associate 
these elements with the conditions of   
success in lectures of this kind4 ,what1

 then1 was my surprise to find ,faraday1
 the acknowledged leader of the world in
 his science1 and who had every means of
 illustration at his command1 using the 
plainest language and the simplest      
tools4 ,when1 in my youthful admiration 
at the result1 ,i expressed1 after one  
of the lectures1 my surprise at the     
simplicity of the means employed1 the   
great master replied3 ,that is the whole
 secret of interesting these young      
people4 ,i always use the simplest      
means1 but ,i never leave a point not   
illustrated4 ,if ,i mention the force of
 gravitation ,i take up a stone and let 
it drop4 ,at this distance of time1 ,i  
can not be sure that ,i quote his exact 
language1 but the lesson and the        
illustration ,i could not forget2 and to
 this lesson1 more than to any other one
 thing1 ,i owe whatever success ,i have 
had as a teacher of physical science4   
,i repeat1 therefore1 it is not only    
useless but injurious in the education  
of young minds to present any department

 of physical science as a body of       
definitions1 principles1 laws1 or       
theories2 and that in elementary schools
 such facts only should be taught as can
 be verified either by the experience of
 the pupils or by the simplest          
experiments1 which the pupils can repeat
 by themselves2 and now1 after this     
discussion1 ,i add1 that the teacher    
must depend on his own ingenuity for his
 experiments1 and on his intercourse    
with his pupils for his instruction4    
,but you will tell me all this involves 
grave difficulties1 and conditions      
incompatible with our ordinary school   
life4 ,i freely admit the difficulties1 
but ,i am none the less sure that1      
unless science can be taught on the     
principles ,i have endeavored to        
illustrate1 it had better not be taught 
at all4 ,i know very well that the      
proper teaching of physical science is  
wholly incompatible with our usual      
school methods4 ,but this only proves to
 me that these methods ought to be      

changed1 and ,i am persuaded that the   
changes required will benefit the       
literary and classical as well as the   
scientific courses of study4 ,for do not
 the same general principles apply to   
the acquisition of knowledge in all     
subjects8 ,and when a child's perceptive
 faculties have been duly stimulated1   
and his intelligence fully awakened1 he 
will find interest in grammar1 in       
literature1 or in history1 as well as in
 science4  ,in repelling the reproach of
 narrowness1 to which our elective      
system at ,cambridge undoubtedly        
frequently leads1 how often have ,i     
urged the self-evident proposition that 
to arouse a love of study in any        
subject1 ,i care not how subordinate its
 importance or how limited its scope1 is
 to take the first step toward making   
your man a scholar2 while to fail to    
gain his interest in any study is to    
lose the whole end of education--and    
what is true of the man is still more   
true of the child4 ,classical culture on

 the one hand and scientific culture on 
the other are excellent things1 but1 if 
your boy can not be made to take an     
interest either in classics or in       
science1 how plain it is that such      
treasures are not for him1 and1 in the  
absence of the one condition which can  
give value to any study1 how idle and   
inconsequent all questions in regard to 
the relative merits of these studies    
appear6 ,on the other hand1 a love of   
study once gained1 all studies are alike
 good4  ,and as with the pupil1 so with 
the teacher4 ,no teaching is of any real
 value that does not come directly from 
the intelligence1 and heart of the      
teacher1 and thus appeals to the        
intelligence and heart of the pupil4    
,it1 of course1 implies more            
acquisition1 and it requires far more   
energy to teach from one's own knowledge
 than to teach from a book1 but then1   
just in proportion to the difficulties  
overcome1 does the teacher raise his    
profession and ennoble himself4 ,there  

is no nobler service than the life of a 
true teacher2 but the mere task-master  
has no right to the teacher's name1 and 
can never attain the teacher's reward4  
,,iv4  ,,the ,,radiometer3 ,a ,,fresh   
,,evidence ,,of ,a ,,molecular          
,,universe4      ,a ,lecture delivered  
in the ,sanders ,theatre of ,harvard    
,university1 ,march #f1 #ahgh4   ,no one
 who is not familiar with the history of
 physical science can appreciate how    
very modern are those grand conceptions 
which add so much to the loftiness of   
scientific studies2 and1 of the many    
who1 on one of our starlit nights1 look 
up into the depths of space1 and are    
awed by the thoughts of that immensity  
which come crowding upon the mind1 there
 are few1 ,i imagine1 who realize the   
fact that almost all the knowledge which
 gives such great sublimity to that     
sight is the result of comparatively    
recent scientific investigation2 and    
that the most elementary student can now
 gain conceptions of the immensity of   

the universe of which the fathers of    
astronomy never dreamed4 ,and how very  
grand are the familiar astronomical     
facts which the sight of the starry     
heavens suggests6  ,those brilliant     
points are all suns like the one which  
forms the center of our system1 and     
around which our earth revolves2 yet so 
inconceivably remote1 that1 although    
moving through space with an incredible 
velocity1 they have not materially      
changed their relative position since   
recorded observations began4 ,compared  
with their distance1 the distance of our
 own sun--#ib1jjj1jjj miles--seems as   
nothing2 yet how inconceivable even that
 distance is when we endeavor to mete it
 out with our terrestrial standards6    
,for if1 when ,copernicus--the great    
father of modern astronomy--died1 in    
#aedc1 just at the close of the         
,protestant ,reformation1 a messenger   
had started for the sun1 and traveled   
ever since with the velocity of a       
railroad train--thirty miles an hour--he

 would not yet have reached his         
destination6  ,evidently1 then1 no      
standards1 which1 like our ordinary     
measures1 bear a simple or at least a   
conceivable relation to the dimensions  
of our own bodies1 can help us to       
stretch a line in such a universe4 ,we  
must seek for some magnitude which is   
commensurate with these immensities of  
space2 and1 in the wonderfully rapid    
motion of light1 astronomy furnishes us 
with a suitable standard4 ,by the       
eclipses of ,jupiter's satellites the   
astronomers have determined that this   
mysterious effluence reaches us from the
 sun in eight minutes and a half1 and   
therefore must travel through space with
 the incredible velocity--shall ,i dare 
to name it8--of #ahf1jjj miles in a     
second of time6 ,yet1 inconceivably     
rapid as this motion is1 capable of     
girdling the earth nearly eight times in
 a single second1 the very nearest of   
the fixed stars1 alpha ,centauri1 is so 
remote that the light by which it will  

be seen in the southern heavens         
to-night1 near that magnificent         
constellation1 the ,southern ,cross1    
must have started on its journey three  
years and a half ago4 ,but this light   
comes from merely the threshold of the  
stellar universe2 and the telescope     
reveals to us stars so distant that1 had
 they been blotted out of existence when
 history began1 the tidings of the event
 could not yet have reached the earth6  
,compare now with these grand           
conceptions the popular belief of only a
 few centuries back4 ,where we look into
 the infinite depths1 our ,puritan      
forefathers saw only a solid dome       
hemming in the earth and skies1 and     
through whose opened doors the rain     
descended4 ,they regarded the sun and   
moon merely as great luminaries set in  
this firmament to rule the day and      
night1 and to their understandings the  
stars served no better purpose than the 
spangles which glitter on the azure     
ceiling of many a modern church4 ,the   

great work of ,copernicus1 ,de ,orbium  
,coelestium ,revolutionibus1 which was  
destined1 ultimately1 to overthrow the  
crude cosmography which ,christianity   
had inherited from ,judaism1 was not    
published until just at the close of the
 author's life in #aedc1 the date before
 mentioned4 ,the telescope1 which was   
required to fully convince the world of 
its previous error1 was not invented    
until more than half a century later1   
and it was not until #ahce that ,struve 
detected the parallax of alpha ,lyrae4  
,the measurement of this parallax1      
together with ,bessel's determination of
 the parallax of #fa ,cygni1 and        
,henderson's that of alpha ,centauri1 at
 about the same time1 gave us our first 
accurate knowledge of the distances of  
the fixed stars4  ,to the thought ,i    
have endeavored to express1 ,i must add 
another1 before ,i can draw the lesson  
which ,i wish to teach4 ,great          
scientific truths become popularized    
very slowly1 and1 after they have been  

thoroughly worked out by the            
investigators1 it is often many years   
before they become a part of the current
 knowledge of mankind4 ,it was fully a  
century after ,copernicus died1 with his
 great volume--still wet from the press 
of ,nuremberg--in his hands1 before the 
,copernican theory was generally        
accepted even by the learned2 and the   
intolerant spirit with which this work  
was received and the persecution which  
,galileo encountered more than half a   
century later were due solely to the    
circumstance that the new theory tended 
to subvert the popular faith in the     
cosmography of the ,church4 ,in modern  
times1 with the many popular expositors 
of science1 the diffusion of new truth  
is more rapid2 but even now there is    
always a long interval after any great  
discovery in abstract science before the
 new conception is translated into the  
language of common life1 so that it can 
be apprehended by the mass even of      
educated men4  ,i have thus dwelt on    

what must be familiar facts in the past 
history of astronomy1 because they      
illustrate and will help you to realize 
the present condition of a much younger 
branch of physical science2 for1 in the 
transition period ,i have described1    
there exists now a conception which     
opens a vision into the microcosmos     
beneath us as extensive and as grand as 
that which the ,copernican theory       
revealed into the macrocosmos above us4 
,the conception to which ,i refer will  
be at once suggested to every scientific
 scholar by the word molecule4 ,this    
word is a ,latin diminutive1 which      
means1 primarily1 a small mass of       
matter2 and1 although heretofore often  
applied in mechanics to the indefinitely
 small particles of a body between which
 the attractive or repulsive forces     
might be supposed to act1 it has only   
recently acquired the exact significance
 with which we now use it4  ,in         
attempting to discover the original     
usage of the word molecule1 ,i was      

surprised to find that it was apparently
 first introduced into science by the   
great ,french naturalist1 ,buffon1 who  
employed the term in a very peculiar    
sense4 ,buffon does not seem to have    
been troubled with the problem which so 
engrosses our modern naturalists--how   
the vegetable and animal kingdoms were  
developed into their present            
condition--but he was greatly exercised 
by an equally difficult problem1 which  
seems to have been lost sight of in the 
present controversy1 and which is just  
as obscure to-day as it was in ,buffon's
 time1 at the close of the last century1
 and that is1 ,why species are so       
persistent in ,nature2 why the acorn    
always grows into the oak1 and why every
 creature always produces of its kind4  
,and1 if you will reflect upon it1 ,i am
 sure you will conclude that this last  
is by far the more fundamental problem  
of the two1 and one which necessarily   
includes the first4 ,that1 of two eggs1 
in which no anatomist can discover any  

structural difference1 the one should1  
in a few short years1 develop an        
intelligence like ,newton's1 while the  
other soon ends in a ,guinea-pig1 is    
certainly a greater mystery than that1  
in the course of unnumbered ages1       
monkeys1 by insensible gradations1      
should grow into men4  ,in order to     
explain the remarkable constancy of     
species1 ,buffon advanced a theory      
which1 when freed from a good deal that 
was fanciful1 may be expressed thus3    
,the attributes of every species1       
whether of plants or of animals1 reside 
in their ultimate particles1 or1 to use 
a more philosophical but less familiar  
word1 inhere in these particles1 which  
,buffon names organic molecules4        
,according to ,buffon1 the oak owes all 
the peculiarities of its organization to
 the special oak molecules of which it  
consists2 and so all the differences in 
the vegetable or animal kingdom1 from   
the lowest to the highest species1      
depend on fundamental peculiarities with

 which their respective molecules were  
primarily endowed4 ,there must1 of      
course1 be as many kinds of molecules as
 there are different species of living  
beings2 but1 while the molecules of the 
same species were supposed to be exactly
 alike1 and to have a strong affinity or
 attraction for each other1 those of    
different species were assumed to be    
inherently distinct and to have no such 
affinities4 ,buffon further assumed that
 these molecules of organic nature were 
diffused more or less widely through the
 atmosphere and through the soil1 and   
that the acorn grew to the oak simply   
because1 consisting itself of oak       
molecules1 it could draw only oak       
molecules from the surrounding media4   
,with our present knowledge of the      
chemical constitution of organic beings1
 we can find a great deal that is both  
fantastic and absurd in this theory of  
,buffon2 but it must be remembered that 
the science of chemistry is almost      
wholly a growth of the present century1 

while ,buffon died in #aghh2 and1 if we 
look at the theory solely from the      
standpoint of his knowledge1 we shall   
find in it much that was worthy of this 
great man4 ,indeed1 in our time1 the    
essential features of the theory of     
,buffon have been transferred from      
natural history to chemistry almost     
unchanged4  ,according to our modern    
chemistry1 the qualities of every       
substance reside or inhere in its       
molecules4 ,take this lump of sugar4 ,it
 has certain qualities with which every 
one is familiar4 ,are those qualities   
attributes of the lump or of its parts8 
,certainly of its parts2 for1 if we     
break up the lump1 the smallest         
particles will still taste sweet and    
show all the characteristics of sugar4  
,could we1 then1 carry on this          
subdivision indefinitely1 provided only 
we had senses or tests delicate enough  
to recognize the qualities of sugar in  
the resulting particles8 ,to this       
question1 modern chemistry answers      

decidedly1 ,no6 ,you would before long  
reach the smallest mass that can have   
the qualities of sugar4 ,you would have 
no difficulty in breaking up these      
masses1 but you would then obtain1 not  
smaller particles of sugar1 but         
particles of those utterly different    
substances which we call carbon1 oxygen1
 and hydrogen--in a word1 particles of  
the elementary substances of which sugar
 consists4 ,these ultimate particles of 
sugar we call the molecules of sugar1   
and thus we come to the present chemical
 definition of a molecule1 ,the smallest
 particles of a substance in which its  
qualities inhere1 which1 as you see1 is 
a reproduction of ,buffon's idea1       
although applied to matter and not to   
organism4  ,a lump of sugar1 then1 has  
its peculiar qualities because it is an 
aggregate of molecules which have those 
qualities1 and a lump of salt differs   
from a lump of sugar simply because the 
molecules of salt differ from those of  
sugar1 and so with every other          

substance4 ,there are as many kinds of  
molecules in ,nature as there are       
different substances1 but all the       
molecules of the same substance are     
absolutely alike in every respect4      
,thus far1 as you see1 we are merely    
reviving in a different association the 
old ideas of ,buffon4 ,but just at this 
point comes in a new conception1 which  
gives far greater grandeur to our modern
 theory3 for we conceive that those     
smallest particles in which the         
qualities of a substance inhere are     
definite bodies or systems of bodies    
moving in space1 and that a lump of     
sugar is a universe of moving worlds4   
,if on a clear night you direct a       
telescope to one of the many            
star-clusters of our northern heavens1  
you will have presented to the eye as   
good a diagram as we can at present draw
 of what we suppose would1 under certain
 circumstances1 be seen in a lump of    
sugar if we could look into the         
molecular universe with the same        

facility with which the telescope       
penetrates the depths of space4  ,do you
 tell me that the absurdities of ,buffon
 were wisdom when compared with such    
wild speculations as these8 ,the        
criticism is simply what ,i expected1   
and ,i must remind you that1 as ,i      
intimated at the outset1 this conception
 of modern science is in the transition 
period of which ,i then spoke1 and1     
although very familiar to scientific    
scholars1 has not yet been grasped by   
the popular mind4 ,i can further only   
add that1 wild as it may appear1 the    
idea is the growth of legitimate        
scientific investigation1 and express my
 conviction that it will soon become as 
much a part of the popular belief as    
those grand conceptions of astronomy to 
which ,i have referred4  ,do you rejoin 
that we can see the suns in a stellar   
cluster1 but can not even begin to see  
the molecules8 ,i must again remind you 
that1 in fact1 you only see points of   
light in the field of the telescope1 and

 that your knowledge that these points  
are immensely distant suns is an        
inference of astronomical science2 and1 
further1 that our knowledge--if ,i may  
so call our confident belief--that the  
lump of sugar is an aggregate of moving 
molecules is an equally legitimate      
inference of molecular mechanics1 a     
science which1 although so much newer1  
is as positive a field of study as      
astronomy4 ,moreover1 sight is not the  
only avenue to knowledge2 and1 although 
our material limitations forbid us to   
expect that the microscope will ever be 
able to penetrate the molecular         
universe1 yet we feel assured that we   
have been able by strictly experimental 
methods to weigh molecular masses and   
measure molecular magnitudes with as    
much accuracy as those of the fixed     
stars4  ,of all forms of matter the gas 
has the simplest molecular structure1   
and1 as might be anticipated1 our       
knowledge of molecular magnitudes is as 
yet chiefly confined to materials of    

this class4 ,i have given below some of 
the results which have been obtained in 
regard to the molecular magnitudes of   
hydrogen gas1 one of the best studied of
 this class of substances2 and1 although
 the vast numbers are as inconceivable  
as are those of astronomy1 they can not 
fail to impress you with the reality of 
the magnitudes they represent4 ,i take  
hydrogen gas for my illustration rather 
than air1 because our atmosphere is a   
mixture of two gases1 oxygen and        
nitrogen1 and therefore its condition is
 less simple than that of a perfectly   
homogeneous material like hydrogen4 ,the
 molecular dimensions of other          
substances1 although varying very       
greatly in their relative values1 are of
 the same order of magnitude as these4,a
    ,a ,as some of the readers of this  
volume may be interested to             
compare these values1 we reproduce the  
,table of ,molecular ,data       from   
,professor ,clerk ,maxwell's lecture on 
,molecules1 delivered       before the  

,british ,association at ,bradford1 and 
published in       ,nature1 ,september  
#be1 #ahgc4        ,molecular           
,magnitudes at ,standard ,temperature   
and ,pressure1 #j deg4 ,c4       and #gf
 c4 m4                                  
----------------------------------------
----------------------       ,,rank     
,,according ,,to       ,hydrogen4       
,oxygen4  ,carbonic  ,carbonic          
,,accuracy ,,of ,,knowledge4            
,oxide4   ,dioxide4                     
----------------------------------------
----------------------       ,,rank ,i4 
,relative mass                  #a      
#af       #ad        #bb       ,velocity
 in metres                              
per second               #a1hei         
#dfe      #dig       #cif               
,,rank ,,ii4                            
,mean path in ten                       
billionths 7#aj-aj7                     
of a metre                 #ife         
#efj      #dhb       #cgi               
,collisions each                        

second--number of                       
millions                #ag1gej         
#g1fdf    #i1dhi     #i1gbj             
,,rank ,,iii4                           
,diameter in hundred                    
billionths 7#aj-aa7                     
of a metre                  #eh         
#gf       #hc        #ic       ,mass in 
ten million                             
million million                         
millionths 7#aj-be7                     
of a gramme                 #df         
#gcf      #fdd     #a1jab               
----------------------------------------
----------------------        ,number of
 molecules in one cubic centimetre of   
every gas is       nineteen million     
million million on #ai 7#ajah74         
,two million hydrogen molecules side by 
side measure a little       over one    
millimetre4  ,dimension of ,hydrogen    
,molecules calculated for ,temperature  
of ,melting ,ice1 and for the ,mean     
,height of the ,barometer of the ,sea   
,level3    ,mean velocity1 #f1jii feet a

 second4   ,mean path1 #ca              
ten-millionths of an inch4              
,collisions1 #ag1gej millions each      
second4   ,diameter1 #dch1jjj1 side by  
side1 measure #a_/ajj of an inch4       
,mass1 #ad 7millions#c7 weigh #a_/ajjj  
of a grain4   ,gas-volume1 #caa         
7millions#c7 fill one cubic inch4  ,to  
explain how the values here presented   
were obtained would be out of place in a
 popular lecture1,b but a few words in  
regard to two or three of the data are  
required to elucidate the subject of    
this lecture4    ,b ,see ,professor     
,maxwell's lecture1 loc4 cit42 also1    
,appletons'       ,cyclopaedia1 article 
,molecules4  ,first1 then1 in regard to 
the mass or weight of the molecules4 ,so
 far as their relative values are       
concerned1 chemistry gives us the means 
of determining the molecular weights    
with very great accuracy2 but when we   
attempt to estimate their weights in    
fractions of a grain--the smallest of   
our common standards--we can not expect 

precision1 simply because the magnitudes
 compared are of such a different order2
 and the same is true of most of the    
other absolute dimensions1 such as the  
diameter and volume of the molecules4   
,we only regard the values given in our 
table as a very rough estimate1 but     
still we have good grounds for believing
 that they are sufficiently accurate to 
give us a true idea of the order of the 
quantities with which we are dealing2   
and it will be seen that1 although the  
numbers required to express the         
relations to our ordinary standards are 
so large1 these molecular magnitudes are
 no more removed from us on the one side
 than are those of astronomy on the     
other4  ,passing next to the velocity of
 the molecular motion1 we find in that a
 quantity which1 although large1 is     
commensurate with the velocity of sound1
 the velocity of a rifle-ball1 and the  
velocities of many other motions with   
which we are familiar4 ,we are1         
therefore1 not comparing1 as before1    

quantities of an utterly different      
order1 and we have confidence that we   
have been able to determine the value   
within very narrow limits of error4 ,but
 how surprising the result is6 ,those   
molecules of hydrogen are constantly    
moving to and fro with this great       
velocity1 and not only are the molecules
 of all aeriform substances moving at   
similar1 although differing rates1 but  
the same is equally true of the         
molecules of every substance1 whatever  
may be its state of aggregation4  ,the  
gas is the simplest molecular condition 
of matter1 because in this state the    
molecules are so far separated from each
 other that their motions are not       
influenced by mutual attractions4       
,hence1 in accordance with the          
well-known laws of motion1 gas molecules
 must always move in straight lines and 
with a constant velocity until they     
collide with each other or strike       
against the walls of the containing     
vessel1 when1 in consequence of their   

elasticity1 they at once rebound and    
start on a new path with a new velocity4
 ,in these collisions1 however1 there is
 no loss of motion1 for1 as the         
molecules have the same weight and are  
perfectly elastic1 they simply change   
velocities1 and whatever one may lose   
the other must gain4  ,but1 if the      
velocity changes in this way1 you may   
ask1 ,what meaning has the definite     
value given in our table8 ,the answer   
is1 that this is the mean value of the  
velocity of all the molecules in a mass 
of hydrogen gas under the assumed       
conditions2 and1 by the principle just  
stated1 the mean value can not be       
changed by the collisions of the        
molecules among themselves1 however     
great may be the change in the motion of
 the individuals4  ,in both liquids and 
solids the molecular motions are        
undoubtedly as active as in a gas1 but  
they must be greatly influenced by the  
mutual attractions which hold the       
particles together1 and hence the       

conditions are far more complicated1 and
 present a problem which we have been   
able to solve only very imperfectly1 and
 with which1 fortunately1 we have not at
 present to deal4  ,limiting1 then1 our 
study to the molecular condition of a   
gas1 picture to yourselves what must be 
the condition of our atmosphere1 with   
its molecules flying about in all       
directions4 ,conceive what a molecular  
storm must be raging about us1 and how  
it must beat against our bodies and     
against every exposed surface4 ,the     
molecules of our atmosphere move1 on an 
average1 nearly four 7#c4h7 times slower
 than those of hydrogen under the same  
conditions2 but then they weigh1 on an  
average1 fourteen and a half times more 
than hydrogen molecules1 and therefore  
strike with as great energy4 ,and do not
 think that the effect of these blows is
 insignificant because the molecular    
projectiles are so small2 they make up  
by their number for what they want in   
size4  ,consider1 for example1 a cubic  

yard of air1 which1 if measured at the  
freezing-point1 weighs considerably over
 two pounds4 ,that cubic yard of        
material contains over two pounds of    
molecules1 which are moving with an     
average velocity of #a1fje feet a       
second1 and this motion is equivalent1  
in every respect1 to that of a          
cannon-ball of equal weight rushing     
along its path at the same tremendous   
rate4 ,of course1 this is true of every 
cubic yard of air at the same           
temperature2 and1 if the motion of the  
molecules of the atmosphere around us   
could by any means be turned into one   
and the same direction1 the result would
 be a hurricane sweeping over the earth 
with this velocity--that is1 at the rate
 of #a1jid miles an hour--whose         
destructive violence not even the       
,pyramids could withstand4  ,living as  
we do in the midst of a molecular       
tornado capable of such effects1 our    
safety lies wholly in the circumstance  
that the storm beats equally in all     

directions at the same time1 and the    
force is thus so exactly balanced that  
we are wholly unconscious of the tumult4
 ,not even the aspen-leaf is stirred1   
nor the most delicate membrane broken2  
but let us remove the air from one of   
the surfaces of such a membrane1 and    
then the power of the molecular storm   
becomes evident1 as in the familiar     
experiments with an air-pump4  ,as has  
already been intimated1 the values of   
the velocities both of hydrogen and of  
air molecules given above were measured 
at a definite temperature1 #cb deg4 of  
our ,fahrenheit thermometer1 the        
freezing point of water2 and this       
introduces a very important point       
bearing on our subject1 namely1 that the
 molecular velocities vary very greatly 
with the temperature4 ,indeed1 according
 to our theory1 this very molecular     
motion constitutes that state or        
condition of matter which we call       
temperature4 ,a hot body is one whose   
molecules are moving comparatively      

rapidly1 and a cold body one in which   
they are moving comparatively slowly4   
,without1 however1 entering into further
 details1 which would involve the whole 
mechanical theory of heat1 let me call  
your attention to a single consequence  
of the principle ,i have stated4  ,when 
we heat hydrogen1 air1 or any mass of   
gas1 we simply increase the velocity of 
its moving molecules4 ,when we cool the 
gas1 we simply lessen the velocity of   
the same molecules4 ,take a current of  
air which enters a room through a       
furnace4 ,in passing it comes in contact
 with heated iron1 and1 as we say1 is   
heated4 ,but1 as we view the process1   
the molecules of the air1 while in      
contact with the hot iron1 collide with 
the very rapidly oscillating metallic   
molecules1 and fly back as a            
billiard-ball would under similar       
circumstances1 with a greatly increased 
velocity1 and it is this more rapid     
motion which alone constitutes the      
higher temperature4  ,consider1 next1   

what must be the effect on the surface4 
,a moment's reflection will show that   
the normal pressure exerted by the      
molecular storm1 always raging in the   
atmosphere1 is due not only to the      
impact of the molecules1 but also to the
 reaction caused by their rebound4 ,when
 the molecules rebound1 they are1 as it 
were1 driven away from the surface in   
virtue of the inherent elasticity both  
of the surface and of the molecules4    
,now1 what takes place when one mass of 
matter is driven away from another--when
 a cannon-ball is driven out of a gun1  
for example8 ,why1 the gun kicks6 ,and  
so every surface from which molecules   
rebound must kick2 and1 if the velocity 
is not changed by the collision1 one    
half of the pressure caused by the      
molecular bombardment is due to the     
recoil4 ,from a heated surface1 as we   
have said1 the molecules rebound with an
 increased velocity1 and hence the      
recoil must be proportionally increased1
 determining a greater pressure against 

the surface4  ,according to this theory1
 then1 we should expect that the air    
would press unequally against surfaces  
at different temperatures1 and that1    
other things being equal1 the pressure  
exerted would be greater the higher the 
temperature of the surface4 ,such a     
result1 of course1 is wholly contrary to
 common experience1 which tells us that 
a uniform mass of air presses equally in
 all directions and against all surfaces
 of the same area1 whatever may be their
 condition4 ,it would seem1 then1 at    
first sight1 as if we had here met with 
a conspicuous case in which our theory  
fails4 ,but further study will convince 
us that the result is just what we      
should expect in a dense atmosphere like
 that in which we dwell2 and1 in order  
that this may become evident1 let me    
next call your attention to another     
class of molecular magnitudes4  ,it must
 seem strange indeed that we should be  
able to measure molecular velocities2   
but the next point ,i have to bring to  

your notice is stranger yet1 for we are 
confident that we have been able to     
determine with approximate accuracy for 
each kind of gas molecule the average   
number of times one of these little     
bodies runs against its neighbors in a  
second1 assuming1 of course1 that the   
conditions of the gas are given4        
,knowing1 now1 the molecular velocity   
and the number of collisions a second1  
we can readily calculate the mean path  
of the molecule--that is1 the average   
distance it moves1 under the same       
conditions1 between two successive      
collisions4 ,of course1 for any one     
molecule1 this path must be constantly  
varying2 since1 while at one time the   
molecule may find a clear coast and make
 a long run1 the very next time it may  
hardly start before its course is       
arrested4 ,still1 taking a mass of gas  
under constant conditions1 the doctrine 
of averages shows that the mean path    
must have a definite value1 and an      
illustration will give an idea of the   

manner in which we have been able to    
estimate it4  ,the nauseous1 smelling   
gas we call sulphide of hydrogen has a  
density only a little greater than that 
of air1 and its molecules must therefore
 move with very nearly as great velocity
 as the average air molecule--that is to
 say1 about fourteen hundred and eighty 
feet a second2 and we might therefore   
expect that1 on opening a jar of the    
gas1 its molecules would spread         
instantly through the surrounding       
atmosphere4 ,but1 so far from this1 if  
the air is quiet1 so that the gas is not
 transported by currents1 a very        
considerable time will elapse before the
 characteristic odor is perceived on the
 opposite side of an ordinary room4 ,the
 reason is obvious3 the molecules must  
elbow their way through the crowd of air
 molecules which already occupy the     
space1 and can therefore advance only   
slowly2 and it is obvious that1 the     
oftener they come into collision with   
their neighbors1 the slower their       

progress must be4 ,knowing1 then1 the   
mean velocity of the molecular motion1  
and being able to measure by appropriate
 means the rate of diffusion1 as it is  
called1 we have the data from which we  
can calculate both the number of        
collisions in a second and also the mean
 path between two successive collisions4
 ,the results1 as we must expect1 are of
 the same order as the other molecular  
magnitudes4 ,but1 inconceivably short as
 the free,c path of a molecule certainly
 is1 it is still1 in the case of        
hydrogen gas1 #acf times the diameter of
 the moving body1 which would certainly 
be regarded among men as quite ample    
elbow-room4    ,c ,there is an obvious  
distinction between the free and the    
disturbed path of a molecule1 and we can
 not overlook in       our calculations 
the perturbations which the collisions  
necessarily entail4 ,such considerations
 greatly complicate       the problem1  
which is far more difficult than would  
appear       from the superficial view  

of the subject that can alone be        
given in a popular lecture4  ,although1 
in this lecture1 ,i have as yet had no  
occasion to mention the radiometer1 ,i  
have by no means forgotten my main      
subject1 and everything which has been  
said has had a direct bearing on the    
theory of this remarkable instrument2   
and still1 before you can understand the
 great interest with which it is        
regarded1 we must follow out another    
line of thought1 converging on the same 
point4  ,one of the most remarkable     
results of modern science is the        
discovery that all energy at work on the
 surface of this planet comes from the  
sun4 ,most of you probably saw1 at our  
,centennial ,exhibition1 that great     
artificial cascade in ,machinery ,hall1 
and were impressed with the power of the
 steam-pump which could keep flowing    
such a mass of water4 ,but1 also1 when  
you stood before the falls at ,niagara1 
did you realize the fact that the       
enormous floods of water which you saw  

surging over those cliffs were in like  
manner supplied by an all-powerful pump1
 and that pump the sun8 ,and not only is
 this true1 but it is equally true that 
every drop of water that falls1 every   
wave that beats1 every wind that blows1 
every creature that moves on the surface
 of the earth1 one and all1 are animated
 by that mysterious effluence we call   
the sunbeam4 ,i say mysterious          
effluence2 for how that power is        
transmitted over those #ib1jjj1jjj miles
 between the earth and the sun is still 
one of the greatest mysteries of        
,nature4  ,in the science of optics1 as 
is well known1 the phenomena of light   
are explained by the assumption that the
 energy is transmitted in waves through 
a medium which fills all space called   
the luminiferous ether1 and there is no 
question that this theory of ,nature1   
known in science as the ,undulatory     
,theory of ,light1 is1 as a working     
hypothesis1 one of the most             
comprehensive and searching which the   

human mind has ever framed4 ,it has both
 correlated known facts and pointed the 
way to remarkable discoveries4 ,but1 the
 moment we attempt to apply it to the   
problem before us1 it demands conditions
 which tax even a philosopher's         
credulity4  ,as sad experience on the   
ocean only too frequently teaches1      
energy can be transmitted by waves as   
well as in any other way4 ,but every    
mechanic will tell you that the         
transmission of energy1 whatever be the 
means employed1 implies certain         
well-known conditions4 ,assume that the 
energy is to be used to turn the        
spindles of a cotton mill4 ,the engineer
 can tell you just how many horse-power 
he must supply for every working-day1   
and it is equally true that a definite  
amount of energy must come from the sun 
to do each day's work on the surface of 
the globe4 ,further1 the engineer will  
also tell you that1 in order to transmit
 the power from his turbine or his      
steam-engine1 he must have shafts and   

pulleys and belts of adequate strength1 
and he knows in every case what is the  
lowest limit of safety4 ,in like manner1
 the medium through which the energy    
which runs the world is transmitted must
 be strong enough to do the immense work
 put upon it2 and1 if the energy is     
transmitted by waves1 this implies that 
the medium must have an enormously great
 elasticity1 an elasticity vastly       
greater than that of the best-tempered  
steel4  ,but turn now to the            
astronomers1 and learn what they have to
 tell us in regard to the assumed       
luminiferous ether through which all    
this energy is supposed to be           
transmitted4 ,our planet is rushing in  
its orbit around the sun at an average  
rate of over #a1jjj miles a minute1 and 
makes its annual journey of some        
#eej1jjj1jjj miles in #cfe days1 #f     
hours1 #i seconds1 and #f_/aj of a      
second4 ,mark the tenths2 for           
astronomical observations are so        
accurate that1 if the length of the year

 varied permanently by the tenth of a   
second1 we should know it2 and you can  
readily understand that1 if there were a
 medium in space which offered as much  
resistance to the motion of the earth as
 would gossamer threads to a race-horse1
 the planet could never come up to time1
 year after year1 to the tenth of a     
second4  ,how1 then1 can we save our    
theory by which we set so much1 and     
rightly1 because it has helped us so    
effectively in studying ,nature8 ,if we 
may be allowed such an extravagant      
solecism1 let us suppose that the       
engineer of our previous illustration   
was the hero of a fairy tale4 ,he has   
built a mill1 set a steam-engine in the 
basement1 arranged his spindles above1  
and is connecting the pulleys by the    
usual belts1 when some stern necessity  
requires him to transmit all the energy 
with cobwebs4 ,of course1 a good fairy  
comes to his aid1 and what does she do8 
,simply makes the cobwebs indefinitely  
strong4 ,so the physicists1 not to be   

outdone by any fairies1 make their ether
 indefinitely elastic1 and their theory 
lands them just here1 with a medium     
filling all space1 thousands of times   
more elastic than steel1 and thousands  
on thousands of times less dense than   
hydrogen gas4 ,there must be a fallacy  
somewhere1 and ,i strongly suspect it is
 to be found in our ordinary            
materialistic notions of causation1     
which involve the old metaphysical      
dogma1 nulla actio in distans1 and which
 in our day have culminated in the      
famous apothegm of the ,german          
materialist1 ,kein ,phosphor kein       
,gedanke4  ,but it is not my purpose to 
discuss the doctrines of causation1 and 
,i have dwelt on the difficulty1 which  
this subject presents in connection with
 the undulatory theory1 solely because  
,i wished you to appreciate the great   
interest with which scientific men have 
looked for some direct manifestation of 
the mechanical action of light4 ,it is  
true that the ether waves must have     

dimensions similar to those of the      
molecules discussed above1 and we must  
expect1 therefore1 that they would act  
primarily on the molecules and not on   
masses of matter4 ,but still the        
well-known principles of wave motion    
have led competent physicists to        
maintain that a more or less            
considerable pressure ought to be       
exerted by the ether waves on the       
surfaces against which they beat1 as a  
partial resultant of the molecular      
tremors first imparted4 ,already1 in the
 last century1 attempts were made to    
discover some evidence of such action1  
and in various experiments the sun's    
direct rays were concentrated on films1 
delicately suspended and carefully      
protected from all other extraneous     
influences1 but without any apparent    
effect2 and thus the question remained  
until about three years ago1 when the   
scientific world were startled by the   
announcement of ,mr4 ,crookes1 of       
,london1 that1 on suspending a small    

piece of blackened alder pith in the    
very perfect vacuum which can now be    
obtained with the mercury pump1 invented
 by ,sprengel1 he had seen this light   
body actually repelled by the sun's     
rays2 and they were still more startled1
 when1 after a few further experiments1 
he presented us with the instrument he  
called a radiometer1 in which the sun's 
rays do the no inconsiderable work of   
turning a small wheel4 ,let us examine  
for a moment the construction of this   
remarkable instrument4  ,the moving part
 of the radiometer is a small horizontal
 wheel1 to the ends of whose arms are   
fastened vertical vanes1 usually of     
mica1 and blackened on one side4 ,a     
glass cap forms the hub1 and by the     
glass-blower's art the wheel is inclosed
 in a glass bulb1 so that the cap rests 
on the point of a cambric needle2 and   
the wheel is so delicately balanced on  
this pivot that it turns with the       
greatest freedom4 ,from the interior of 
the bulb the air is now exhausted by    

means of the ,sprengel pump1 until less 
than #a_/ajjj of the original quantity  
is left1 and the only opening is then   
hermetically sealed4 ,if1 now1 the sun's
 light or even the light from a candle  
shines on the vanes1 the blackened      
surfaces--which are coated with         
lampblack--are repelled1 and1 these     
being symmetrically placed around the   
wheel1 the several forces conspire to   
produce the rapid motion which results4 
,the effect has all the appearance of a 
direct mechanical action exerted by the 
light1 and for some time was so regarded
 by ,mr4 ,crookes and other eminent     
physicists1 although in his published   
papers it should be added that ,mr4     
,crookes carefully abstained from       
speculating on the subject--aiming1 as  
he has since said1 to keep himself      
unbiased by any theory1 while he        
accumulated the facts upon which a      
satisfactory explanation might be based4
  ,singularly1 however1 the first       
aspects of the new phenomena proved to  

be wholly deceptive1 and the motion1 so 
far from being an effect of the direct  
mechanical action of the waves of light1
 is now believed to be a new and very   
striking manifestation of molecular     
motion4 ,to this opinion ,mr4 ,crookes  
himself has come1 and1 in a recent      
article1 he writes3 ,twelve months'     
research1 however1 has thrown much light
 on these actions1 and the explanation  
afforded by the dynamical theory of     
gases makes what was a year ago obscure 
and contradictory now reasonable and    
intelligible4  ,as is frequently the    
case in ,nature1 the chief effect is    
here obscured by various subordinate    
phenomena1 and it is not surprising that
 a great difference of opinion should   
have arisen in regard to the cause of   
the motion4 ,this would not be an       
appropriate place to describe the       
numerous investigations occasioned by   
the controversy1 many of which show in a
 most striking manner how easily        
experimental evidence may be honestly   

misinterpreted in support of a          
preconceived opinion4 ,i will1 however1 
venture to trespass further on your     
patience1 so far as to describe the few 
experiments by which1 very early in the 
controversy1 ,i satisfied my own mind on
 the subject4  ,when1 two years ago1 ,i 
had for the first time an opportunity of
 experimenting with a radiometer1 the   
opinion was still prevalent that the    
motion of the wheel was a direct        
mechanical effect of the waves of light1
 and1 therefore1 that the impulses came 
from the outside of the instrument1 the 
waves passing freely through the glass  
envelope4 ,at the outset1 this opinion  
did not seem to me to be reasonable1 or 
in harmony with well-known facts2 for1  
knowing how great must be the molecular 
disturbance caused by the sun's rays1 as
 shown by their heating power1 ,i could 
not believe that a residual action1 such
 as has been referred to1 would first   
appear in these delicate phenomena      
observed by ,mr4 ,crookes1 and should   

only be manifested in the vacuum of a   
mercury pump4  ,on examining the        
instrument1 my attention was at once    
arrested by the lampblack coating on the
 alternate surfaces of the vanes2 and1  
from the remarkable power of lampblack  
to absorb radiant heat1 it was evident  
at once that1 whatever other effects the
 rays from the sun or from a flame might
 cause1 they must necessarily determine 
a constant difference of temperature    
between the two surfaces of the vanes1  
and the thought at once occurred that1  
after all1 the motion might be a direct 
result of this difference of            
temperature--in other words1 that the   
radiometer might be a small heat engine1
 whose motions1 like those of every     
other heat engine1 depend on the        
difference of temperature between its   
parts4  ,but1 if this were true1 the    
effect ought to be proportional solely  
to the heating power of the rays1 and a 
very easy means of roughly testing this 
question was at hand4 ,it is well known 

that an aqueous solution of alum1       
although transmitting light as freely as
 the purest water1 powerfully absorbs   
those rays1 of any source1 which have   
the chief heating power4 ,accordingly1  
,i interposed what we call an alum cell 
in the path of the rays shining on the  
radiometer1 when1 although the light on 
the vanes was as bright as before1 the  
motion was almost completely arrested4  
,this experiment1 however1 was not      
conclusive1 as it might still be said   
that the heat-giving rays acted         
mechanically1 and it must be admitted   
that the chief part of the energy in the
 rays1 even from the most brilliant     
luminous sources1 always takes the form 
of heat4 ,but1 if the action is         
mechanical1 the reaction must be against
 the medium through which the rays are  
transmitted1 while1 if the radiometer is
 simply a heat engine1 the action and   
reaction must be1 ultimately at least1  
between the heater and the cooler1 which
 in this case are respectively the      

blackened surfaces of the vanes and the 
glass walls of the inclosing bulb2 and  
here1 again1 a very easy method of      
testing the actual condition at once    
suggested itself4  ,if the motion of the
 radiometer wheel is an effect of       
mechanical impulses transmitted in the  
direction of the beam of light1 it was  
certainly to be expected that the beam  
would act on the lustrous as well as on 
the blackened mica surfaces1 however    
large might be the difference in the    
resultants producing mechanical motion1 
in consequence of the great absorbing   
power of the lampblack4 ,moreover1 since
 the instrument is so constructed that1 
of two vanes on opposite sides of the   
wheel1 one always presents a blackened  
and the other a lustrous surface to an  
incident beam1 we should further expect 
to find in the motion of the wheel a    
differential phenomenon1 due to the     
unequal action of the light on these    
surfaces4 ,on the other hand1 if the    
radiometer is a heat engine1 and the    

reaction takes place between the heated 
blackened surfaces of the vanes and the 
colder glass1 it is evident that the    
total effect will be simply the sum of  
the effects at the several surfaces4    
,in order to investigate the question   
thus presented1 ,i placed the radiometer
 before a common kerosene lamp1 and     
observed1 with a stop-watch1 the number 
of seconds that elapsed during ten      
revolutions of the little wheel4        
,finding that this number was absolutely
 constant1 ,i next screened one half of 
the bulb1 so that only the blackened    
faces were exposed to the light as the  
wheel turned them into the beam4 ,again1
 ,i several times observed the number of
 seconds during ten turns1 which1       
although equally constant1 was greater  
than before4 ,lastly1 ,i screened the   
blackened surfaces so that1 as the wheel
 turned1 only the lustrous surfaces of  
mica were exposed to the light1 when1 to
 my surprise1 the wheel continued to    
turn in the same direction as before1   

although much more slowly4 ,it appeared 
as if the lustrous surfaces were        
attracted by the light4 ,again ,i       
observed the time of ten revolutions1   
and here ,i have collected my results1  
reducing them1 in the last column1 so as
 to show the corresponding number of    
revolutions in the same time3           
----------------------------------------
----------------------------            
,,conditions4       ,time of ten        
revolutions4  ,no4 of revolutions       
in same time4                           
----------------------------------------
----------------------------   ,both    
faces exposed            #h seconds4    
#cai   ,blackened faces only         #aa
                          #bcb   ,mica  
faces only              #bi             
#hh                                     
----------------------------------------
----------------------------  ,it will  
be noticed that #hh  #bcb equals very   
nearly #cai4 ,evidently the effect1 so  
far from being differential1 is         

concurrent4 ,hence1 the action which    
causes the motion must take place       
between the parts of the instrument1 and
 can not be a direct effect of impulses 
imparted by ether waves2 or else we are 
driven to the most improbable           
alternative1 that lampblack and mica    
should have such a remarkable selective 
power that the impulses imparted by the 
light should exert a repulsive force at 
one surface and an attractive force at  
the other4 ,were there1 however1 such an
 improbable effect1 it must be          
independent of the thickness of the mica
 vanes2 while1 on the other hand1 if1 as
 seemed to us now most probable1 the    
whole effect depended on the difference 
of temperature between the lampblack and
 the mica1 and if the light produced an 
effect on the mica surface only because1
 the mica plate being diathermous to a  
very considerable extent1 the lampblack 
became heated through the plate more    
than the plate itself1 then it would    
follow that1 if we used a thicker mica  

plate1 which would absorb more of the   
heat1 we ought to obtain a marked       
difference of effect4 ,accordingly1 we  
repeated the experiment with an equally 
sensitive radiometer1 which we made for 
the purpose1 with comparatively thick   
vanes1 and with this the effect of a    
beam of light on the mica surface was   
absolutely null1 the wheel revolving in 
the same time1 whether these faces were 
protected or not4  ,but one thing was   
now wanting to make the demonstration   
complete4 ,a heat engine is reversible1 
and if the motion of the radiometer     
depended on the circumstance that the   
temperature of the blackened faces of   
the vanes was higher than that of the   
glass1 then by reversing the conditions 
we ought to reverse the motion4         
,accordingly1 ,i carefully heated the   
glass bulb over a lamp1 until it was as 
hot as the hand would bear1 and then    
placed the instrument in a cold room1   
trusting to the great radiating power of
 lampblack to maintain the temperature  

of the blackened surfaces of the vanes  
below that of the glass4 ,immediately   
the wheel began to turn in the opposite 
direction1 and continued to turn until  
the temperature of the glass came into  
equilibrium with the surrounding        
objects4  ,these early experiments have 
since been confirmed to the fullest     
extent1 and no physicist at the present 
day can reasonably doubt that the       
radiometer is a very beautiful example  
of a heat engine1 and it is the first   
that has been made to work continuously 
by the heat of the sunbeam4 ,but it is  
one thing to show that the instrument is
 a heat engine1 and quite another thing 
to explain in detail the manner in which
 it acts4 ,in regard to the last point1 
there is still room for much difference 
of opinion1 although physicists are     
generally agreed in referring the action
 to the residual gas that is left in the
 bulb4 ,as for myself1 ,i became        
strongly persuaded--after experimenting 
with more than one hundred of these     

instruments1 made under my own eye1 with
 every variation of condition ,i could  
suggest--that the effect was due to the 
same cause which determines gas         
pressure1 and1 according to the         
dynamical theory of gases1 this amounts 
to saying that the effect is due to     
molecular motion4 ,i have not time1     
however1 to describe either my own      
experiments on which this opinion was   
first based1 or the far more thorough   
investigations since made by others1    
which have served to strengthen the     
first impression4,d ,but1 after our     
previous discussions1 a few words will  
suffice to show how the molecular theory
 explains the new phenomena4    ,d ,see 
notice of these investigations by the   
author of this       article1 in        
,american ,journal of ,science and      
,arts1       ,september1 #ahgg 7#c71    
xiv1 #bca4  ,although the air in the    
bulb has been so nearly exhausted that  
less than the one-thousandth part       
remains1 yet it must be borne in mind   

that the number of molecules left behind
 is by no means inconsiderable4 ,as will
 be seen by referring to our table1     
there must still be no less than        
#caa1jjj million million in every cubic 
inch4 ,moreover1 the absolute pressure  
which this residual gas exerts is a very
 appreciable quantity4 ,it is simply the
 one-thousandth of the normal pressure  
of the atmosphere1 that is1 of #ad-g_/aj
 pounds on a square inch1 which is      
equivalent to a little over one hundred 
grains on the same area4 ,now1 the area 
of the blackened surfaces of the vanes  
of an ordinary radiometer measures just 
about a square inch1 and the wheel is   
mounted so delicately that a constant   
pressure of one-tenth of a grain would  
be sufficient to produce rapid motion4  
,so that a difference of pressure on the
 opposite faces of the vanes1 equal to  
one one-thousandth of the whole amount1 
is all that we need account for2 and1 as
 can easily be calculated1 a difference 
of temperature of less than half a      

degree ,fahrenheit would cause all this 
difference in the pressure of the       
rarefied air4  ,but you may ask1 ,how   
can such a difference of pressure exist 
on different surfaces exposed to one and
 the same medium8 and your question is a
 perfectly legitimate one2 for it is    
just here that the new phenomena seem to
 belie all our previous experience4 ,if1
 however1 you followed me in my very    
partial exposition of the mechanical    
theory of gases1 you will easily see    
that on this theory it is a more        
difficult question to explain why such a
 difference of pressure does not        
manifest itself in every gas medium and 
under all conditions between any two    
surfaces having different temperatures4 
,we saw that gas pressure is a double   
effect1 caused both by the impact of    
molecules and by the recoil of the      
surface attending their rebound4 ,we    
also saw that when molecules strike a   
heated surface they rebound with        
increased velocity1 and hence produce an

 increased pressure against the surface1
 the greater the higher the temperature4
 ,according to this theory1 then1 we    
should expect to find the same          
atmosphere pressing unequally on equal  
surfaces if at different temperatures2  
and the difference in the pressure on   
the lampblack and mica surfaces of the  
vanes1 which the motion of the          
radiometer wheel necessarily implies1 is
 therefore simply the normal effect of  
the mechanical condition of every gas   
medium4 ,the real difficulty is1 to     
explain why we must exhaust the air so  
perfectly before the effect manifests   
itself4  ,the new theory is equal to the
 emergency4 ,as has been already pointed
 out1 in the ordinary state of the air  
the amplitude of the molecular motion is
 exceedingly small1 not over a few      
ten-millionths of an inch--a very small 
fraction1 therefore1 of the height of   
the inequalities on the lampblack       
surfaces of the vanes of a radiometer4  
,under such circumstances1 evidently the

 molecules would not leave the heated   
surface1 but simply bound back and forth
 between the vanes and the surrounding  
mass of dense air1 which1 being almost  
absolutely a non-conductor of heat1 must
 act essentially like an elastic solid  
wall confining the vanes on either side4
 ,for the time being1 and until replaced
 by convection currents1 the oscillating
 molecules are as much a part of the    
vanes as our atmosphere is a part of the
 earth2 and on this system1 as a whole1 
the homogeneous dense air which         
surrounds it must press equally from all
 directions4 ,in proportion1 however1 as
 the air is exhausted1 the molecules    
find more room and the amplitude of the 
molecular motion is increased1 and1 when
 a very high degree of exhaustion is    
reached1 the air particles no longer    
bound back and forth on the vanes       
without change of condition1 but they   
either bound off entirely like a ball   
from a cannon1 or else1 having          
transferred a portion of their momentum1

 return with diminished velocity1 and in
 either case the force of the reaction  
is felt4,e    ,e ,the reader will1 of   
course1 distinguish between the         
differential       action on the        
opposite faces of the vanes of the      
radiometer and       the reaction       
between the vanes and the glass which   
are the heater       and the cooler of  
the little engine4 ,nor will it be      
necessary to       remind any student   
that a popular view of such a complex   
subject       must be necessarily       
partial4 ,in the present case we not    
only meet       with the usual          
difficulties in this respect1 but1      
moreover1 the       principles of       
molecular mechanics have not been so    
fully developed       as to preclude    
important differences of opinion between
 equally       competent authorities in 
regard to the details of the theory4 ,to
       avoid misapprehension1 we may    
here add that1 in orderto obtain in     
the radiometer a reaction between the   

heater and the cooler1 it       is not  
necessary that the space between them   
should actually be       crossed by the 
moving molecules4 ,it is only necessary 
that the       momentum should be       
transferred across the space1 and tide  
may       take place along lines        
consisting of many molecules each4 ,the 
theory1 however1 shows that such a      
transfer can only take place       in a 
highly rarefied medium4 ,in an          
atmosphere of ordinary density1         
the accession of heat which the vanes of
 a radiometer might       receive from a
 radiant source would be diffused       
through the mass       of the inclosed  
air4 ,this amounts to saying that the   
momentum       would be so diffused1 and
 hence1 under such circumstances1 the   
molecular motion would not determine any
 reaction between the       vanes and   
the glass envelope4 ,indeed1 a dense    
mass of gas presents       to the       
conduction of heat1 which represents    
momentum1 a wall far       more         

impenetrable than the surrounding glass1
 and the diffusion       of heat is     
almost wholly brought about by          
convection currents       which rise    
from the heated surfaces4 ,it will thus 
be seen that       the great            
non-conducting power of air comes into  
play to prevent       not only the      
transfer of momentum from the vanes to  
the glass1       but also1 almost       
entirely1 any direct transfer to the    
surrounding       mass of gas4 ,hence1  
as stated above1 the heated molecules   
bound       back and forth on the vanes 
without change of condition1 and the    
mass of the air retains its uniform     
tension in all parts of the       bulb1 
except in so far as this is slowly      
altered by the convection       currents
 just referred to4 ,as the atmosphere1  
however1 becomes       less dense1 the  
diffusion of heat by convection         
diminishes1 and       that by molecular 
motion 7conduction7 increases until the 
last       greatly predominates4 ,when1 

now1 the exhaustion reaches so great    
a degree that the heat1 or momentum1 is 
rapidly transferred from       the      
heater to the cooler by an exaggeration1
 or1 possibly1 a       modification1 of 
the mode of action we call conduction1  
then we       have the reaction on which
 the motion of the radiometer wheel     
depends4  ,thus it appears that we have 
been able to show by very definite      
experimental evidence that the          
radiometer is a heat engine4 ,we have   
also been able to show that such a      
difference of temperature as the        
radiation must produce in the air in    
direct contact with the opposite faces  
of the vanes of the radiometer would    
determine a difference of tension1 which
 is sufficient to account for the motion
 of the wheel4 ,finally1 we have shown1 
as fully as is possible in a popular    
lecture1 that1 according to the         
mechanical theory of gases1 such a      
difference of tension would have its    
normal effect only in a highly rarefied 

atmosphere1 and thus we have brought the
 new phenomena into harmony with the    
general principles of molecular         
mechanics previously established4  ,more
 than this can not be said of the       
steam-engine1 although1 of course1 in   
the older engine the measurements on    
which the theory is based are vastly    
more accurate and complete4 ,but the    
moment we attempt to go beyond the      
general principles of heat engines1 of  
which the steam-engine is such a        
conspicuous illustration1 and explain   
how the heat is transformed into motion1
 we have to resort to the molecular     
theory just as in the case of the       
radiometer2 and the motion of the       
steam-engine seems to us less wonderful 
than that of the radiometer only because
 it is more familiar and more completely
 harmonized with the rest of our        
knowledge4 ,moreover1 the very molecular
 theory which we call upon to explain   
the steam-engine involves consequences  
which1 as we have seen1 have been first 

realized in the radiometer2 and thus it 
is that this new instrument1 although   
disappointing the first expectations of 
its discoverer1 has furnished a very    
striking confirmation of this wonderful 
theory4 ,indeed1 the confirmation is so 
remote and yet so close1 so unexpected  
and yet so strong1 that the new         
phenomena almost seem to be a direct    
manifestation of the molecular motion   
which our theory assumes2 and when a new
 discovery thus confirms the accuracy of
 a previous generalization1 and gives us
 additional reason to believe that the  
glimpses we have gained into the order  
of ,nature are trustworthy1 it excites1 
with reason1 among scientific scholars  
the warmest interest4  ,and when we     
consider the vast scope of the molecular
 theory1 the order on order of          
existences which it opens to the        
imagination1 how can we fail to be      
impressed with the position in which it 
places man midway between the molecular 
cosmos on the one side and the stellar  

cosmos on the other--a position in which
 he is able1 in some measure at least1  
to study and interpret both8  ,since the
 time to which we referred at the       
beginning of this lecture1 when man's   
dwelling-place was looked at as the     
center of a creation which was solely   
subservient to his wants1 there has been
 a reaction to the opposite extreme1 and
 we have heard much of the utter        
insignificance of the earth in a        
universe among whose immensities all    
human belongings are but as a drop in   
the ocean4 ,when now1 however1 we learn 
from ,sir ,william ,thomson that the    
drop of water in our comparison is      
itself a universe1 consisting of units  
so small that1 were the drop magnified  
to the size of the earth1 these units   
would not exceed in magnitude a         
cricket-ball1,f and when1 on studying   
chemistry1 we still further learn that  
these units are not single masses but   
systems of atoms1 we may leave the      
illusions of the imagination from the   

one side to correct those from the      
other1 and all will teach us the great  
lesson that man's place in ,nature is   
not to be estimated by relations of     
magnitude1 but by the intelligence which
 makes the whole creation his own4    ,f
 ,nature1 ,no4 #bb1 ,march #ca1 #ahgj4  
,but1 if it is man's privilege to follow
 both the atoms and the stars in their  
courses1 he finds that1 while thus      
exercising the highest attributes of his
 nature1 he is ever in the presence of  
an immeasurably superior intelligence1  
before which he must bow and adore1 and 
thus come to him both the assurance and 
the pledge of a kinship in which his    
only real glory can be found4     ,v4   
,,memoir ,,of ,,thomas ,,graham4        
,reprinted from the ,proceedings of the 
,american ,academy     of ,arts and     
,sciences1 ,vol4 ,,viii1 ,may #bd1      
#ahgj4   ,it would be difficult to find 
in the history of science a character   
more simple1 more noble1 or more        
symmetrical in all its parts than that  

of ,thomas ,graham1 and he will always  
be remembered as one of the most eminent
 of those great students of nature who  
have rendered our ,saxon race           
illustrious4 ,he was born of ,scotch    
parents in ,glasgow in the year #ahje1  
and in that city1 where he received his 
education1 all his early life was       
passed4 ,in #ahcg he went to ,london as 
,professor of ,chemistry in the newly   
established ,london ,university1 now    
called ,university ,college1 and he     
occupied this chair until the year      
#ahee1 when he succeeded ,sir ,john     
,herschel as ,master of the ,royal      
,mint1 a post which he held to the close
 of his life4 ,his death1 on the #afth  
of ,september last 7#ahfi71 at the age  
of sixty1 was caused by no active       
disease1 but was simply the wearing out 
of a constitution enfeebled in youth by 
privations voluntarily and courageously 
encountered that he might devote his    
life to scientific study4 ,as with all  
earnest students1 that life was         

uneventful1 if judged by ordinary       
standards2 and the records of his       
discoveries form the only materials for 
his biography4  ,although one of the    
most successful investigators of        
physical science1 the late ,master of   
the ,mint had not that felicity of      
language or that copiousness of         
illustration which added so much to the 
popular reputation of his distinguished 
contemporary1 ,faraday2 but his         
influence on the progress of science was
 not less marked or less important4     
,both of these eminent men were for a   
long period of years best known to the  
,english public as teachers of          
chemistry1 but their investigations were
 chiefly limited to physical problems2  
yet1 although both cultivated the border
 ground between chemistry and physics1  
they followed wholly different lines of 
research4 ,while ,faraday was so        
successfully developing the principles  
of electrical action1 ,graham with equal
 success was investigating the laws of  

molecular motion4 ,each followed with   
wonderful constancy1 as well as skill1 a
 single line of study from first to     
last1 and to this concentration of power
 their great discoveries are largely    
due4  ,one of the earliest and most     
important of ,graham's investigations1  
and the one which gave the direction to 
his subsequent course of study1 was that
 on the diffusion of gases4 ,it had     
already been recognized that            
impenetrability in its ordinary sense is
 not1 as was formerly supposed1 a       
universal quality of matter4 ,dalton had
 not only recognized that aeriform      
bodies exhibit a positive tendency to   
mix1 or to penetrate through each other1
 even in opposition to the force of     
gravity1 but had made this quality of   
gases the subject of experimental       
investigation4 ,he inferred1 as the     
result of his inquiry1 that different   
gases afford no resistance to each      
other2 but that one gas spreads or      
expands into the space occupied by      

another gas1 as it would rush into a    
vacuum2 at least1 that the resistance   
which the particles of one gas offer to 
those of another is of a very imperfect 
kind1 to be compared to the resistance  
which stones in the channel of a stream 
oppose to the flow of running water4    
,but1 although this theory of ,dalton   
was essentially correct and involved the
 whole truth1 yet it was supported by no
 sufficient evidence1 and he failed to  
perceive the simple law which underlies 
this whole class of phenomena4  ,graham1
 on entering on this inquiry1 found that
 gases diffuse into the atmosphere with 
different degrees of ease and rapidity4 
,this was first observed by allowing    
each gas to diffuse from a bottle into  
the air through a narrow tube in        
opposition to the solicitation of       
gravity4 ,afterward an observation of   
,doebereiner on the escape of hydrogen  
gas by a fissure or crack in a glass    
receiver caused him to vary the         
conditions of his experiments1 and led  

to the invention of the well-known      
diffusion tube4 ,in this simple         
apparatus a thin septum of plaster of   
,paris is used to separate the diffusing
 gases1 which1 while it arrests in a    
great measure all direct currents       
between the two media1 does not         
interfere with the molecular motion4    
,much later1 ,graham found in prepared  
graphite a material far better adapted  
to this purpose than the plaster1 and he
 used septa of this mineral to confirm  
his early results1 in answer to certain 
ill-considered criticisms in ,bunsen's  
work on gasometry4 ,these septa he was  
in the habit of calling his atomic      
filters4  ,by means of the diffusion    
tube1 ,graham was able to measure       
accurately the relative times of        
diffusion of different gases1 and he    
found that equal volumes of any two     
gases interpenetrate each other in times
 which are inversely proportional to the
 square roots of their respective       
densities2 and this fundamental law was 

the greatest discovery of our late      
foreign associate4 ,it is now           
universally recognized as one of the few
 great cardinal principles which form   
the basis of physical science4  ,it can 
be shown1 on the principles of          
pneumatics1 that gases should rush into 
a vacuum with velocities corresponding  
to the numbers which have been found to 
express their diffusion times2 and1 in a
 series of experiments on what he calls 
the effusion of gases1 ,graham confirmed
 by trial this deduction of theory4 ,in 
these experiments a measured volume of  
the gas was allowed to find its way into
 the vacuous jar through a minute       
aperture in a thin metallic plate1 and  
he carefully distinguished between this 
class of phenomena and the flowing of   
gases through capillary tubes into a    
vacuum1 in which case1 however short the
 tube1 the effects of friction          
materially modify the result4 ,this last
 class of phenomena ,graham likewise    
investigated1 and designated by the term

 transpiration4  ,while1 however1 it    
thus appears that the results of        
,graham's investigation were in strict  
accordance with ,dalton's theory1 it    
must also be evident that ,graham was   
the first to observe the exact numerical
 relation which obtains in this class of
 phenomena1 and that all-important      
circumstance entitles him to be regarded
 as the discoverer of the law of        
diffusion4 ,the law1 however1 at first  
enunciated1 was purely empirical1 and   
,graham himself says that something more
 must be assumed than that gases are    
vacua to each other1 in order to explain
 all the phenomena observed2 and        
according to his original view this     
representation of the process was only a
 convenient mode of expressing the final
 result4 ,such has proved to be the     
case4  ,like other great men1 ,graham   
built better than he knew4 ,in the      
progress of physical science during the 
last twenty-five years1 two principles  
have become more and more conspicuous1  

until at last they have completely      
revolutionized the philosophy of        
chemistry4 ,in the first place1 it has  
appeared that a host of chemical as well
 as of physical facts are cooerdinated  
by the assumption that all substances in
 the state of gas have the same         
molecular volume1 or1 in other words1   
contain the same number of molecules in 
a given space2 and in the second place1 
it has become evident that the phenomena
 of heat are simply the manifestations  
of molecular motion4 ,according to this 
view1 the temperature of a body is the  
vis viva of its molecules2 and1 since   
all molecules at a given temperature    
have the same vis viva1 it follows that 
the molecules must move with velocities 
which are inversely proportional to the 
square roots of the molecular weights4  
,moreover1 since the molecular volumes  
are equal1 and the molecular weights    
therefore proportional to the densities 
of the aeriform bodies in which the     
molecules are the active units1 it also 

follows that the velocities of the      
molecules in any two gases are inversely
 proportional to the square roots of    
their respective densities4 ,thus the   
simple numerical relations first        
observed in the phenomena of diffusion  
are the direct result of molecular      
motion2 and it is now seen that         
,graham's empirical law is included     
under the fundamental laws of motion4   
,thus ,graham's investigation has become
 the basis of the new science of        
molecular mechanics1 and his            
measurements of the rates of diffusion  
prove to be the measures of molecular   
velocities4  ,from the study of         
diffusion ,graham passed by a natural   
transition to the investigation of a    
class of phenomena which1 although      
closely allied to the first as to the   
effects produced1 differ wholly in their
 essential nature4 ,here also he        
followed in the footsteps of ,dalton4   
,this distinguished chemist had noticed 
that a bubble of air separated by a film

 of water from an atmosphere of carbonic
 anhydride gradually expanded until it  
burst4 ,in like manner a moist bladder1 
half filled with air and tied1 if       
suspended in an atmosphere of the same  
material1 becomes in time greatly       
distended by the insinuation of this gas
 through its substance4 ,this effect can
 not be the result of simple diffusion1 
for it is to be remembered that the     
thinnest film of water1 or of any       
liquid1 is absolutely impermeable to a  
gas as such1 and1 moreover1 only the    
carbonic anhydride passes through the   
film1 very little or none of the air    
escaping outward4 ,the result depends1  
first1 upon the solution of the carbonic
 anhydride by the water on one surface  
of the film2 secondly1 on the           
evaporation into the air1 from the other
 surface1 of the gas thus absorbed4     
,similar experiments were made by ,drs4 
,mitchell and ,faust1 and others1 in    
which gases passed through a film of    
,india-rubber1 entering into a partial  

combination with the material on one    
surface1 and escaping from it on the    
other4  ,graham not only considerably   
extended our knowledge of this class of 
phenomena1 but also gave us a           
satisfactory explanation of the mode in 
which these remarkable results are      
produced4 ,he recognized in these cases 
the action of a feeble chemical force1  
insufficient to produce a definite      
compound1 but still capable of          
determining a more or less perfect      
union1 as in the case of simple         
solution4 ,he also distinguished the    
influence of mass in causing the        
formation or decomposition of such weak 
chemical compounds4 ,the conditions of  
the phenomena under consideration are   
simply these3  ,first4 ,a material for  
the septum capable of forming a feeble  
chemical union with the gas to be       
transferred4  ,secondly4 ,an excess of  
the gas on one side of the film and a   
deficiency on the other4  ,thirdly4     
,such a temperature that the unstable   

compound may form at the surface1 where 
the aeriform constituent is present in  
large mass1 while it decomposes at the  
opposite surface1 where the quantity is 
less abundant4  ,one of the most        
remarkable results of ,graham's study of
 this peculiar mode of transfer of      
aeriform matter through the very        
substance of solid bodies was an        
ingenious method of separating the      
oxygen from the atmosphere4 ,the        
apparatus consisted simply of a bag of  
,india-rubber kept distended by an      
interior framework1 while it was        
exhausted by a ,sprengel pump4 ,under   
these circumstances the selective       
affinity of the caoutchouc determines   
such a difference in the rate of        
transfer of the two constituents of the 
atmosphere that the amount of oxygen in 
the transpired air rises to forty per   
cent41 and by repeating the process     
nearly pure oxygen may be obtained4 ,it 
was at first hoped that this method     
might find a valuable application in the

 arts1 but in this ,graham was          
disappointed2 for the same result has   
since been effected by purely chemical  
methods1 which are both cheaper and more
 rapid4  ,these experiments on          
,india-rubber naturally led to the study
 of similar effects produced with       
metallic septa1 which1 although to some 
extent previously observed in passing   
gases through heated metallic tubes1 had
 been only imperfectly understood4      
,thus1 when a stream of hydrogen or     
carbonic oxide is passed through a      
red-hot iron tube1 a no inconsiderable  
portion of the gas escapes through the  
walls4 ,the same is true to a still     
greater degree when hydrogen is passed  
through a red-hot tube of platinum1 and 
,graham showed that1 through the walls  
of a tube of palladium1 hydrogen gas    
passes1 under the same conditions1      
almost as rapidly as water through a    
sieve4 ,moreover1 our distinguished     
associate proved that this rapid        
transfer of gas through these dense     

metallic septa was due1 as in the case  
of the ,india-rubber1 to an actual      
chemical combination of its material    
with the metal1 formed at the surface1  
where the gas is in excess1 and as      
rapidly decomposed on the opposite face 
of the septum4 ,he not only recognized  
as belonging to this class of phenomena 
the very great absorption of hydrogen by
 platinum plate and sponge in the       
familiar experiment of the ,doebereiner 
lamp1 but also showed that this gas is a
 definite constituent of meteoric       
iron--a fact of great interest from its 
bearing on the meteoric theory4  ,we are
 thus led to ,graham's last important   
discovery1 which was the justification  
of the theory we have been considering1 
and the crowning of this long line of   
investigation4 ,as may be anticipated   
from what has been said1 the most marked
 example of that order of chemical      
compounds1 to which the metallic        
transpiration of aeriform matter we have
 been considering is due1 is the        

compound of palladium with hydrogen4    
,graham showed that1 when a plate of    
this metal is made the negative pole in 
the electrolysis of water1 it absorbs   
nearly one thousand times its volume of 
hydrogen gas--a quantity approximatively
 equivalent to one atom of hydrogen to  
each atom of palladium4 ,he further     
showed that the metal thus becomes so   
profoundly altered as to indicate that  
the product of this union is a definite 
compound4 ,not only is the volume of the
 metal increased1 but its tenacity and  
conducting power for electricity are    
diminished1 and it acquires a slight    
susceptibility to magnetism1 which the  
pure metal does not possess4 ,the       
chemical qualities of this product are  
also remarkable4 ,it precipitates       
mercury from a solution of its chloride1
 and in general acts as a strong        
reducing agent4 ,exposed to the action  
of chlorine1 bromine1 or iodine1 the    
hydrogen leaves the palladium and enters
 into direct union with these elements4 

,moreover1 although the compound is     
readily decomposed by heat1 the gas can 
not be expelled from the metal by simple
 mechanical means4  ,these facts recall 
the similar relations frequently        
observed between the qualities of an    
alloy and those of the constituent      
metals1 and suggest the inference made  
by ,graham1 that palladium charged with 
hydrogen is a compound of the same      
class--a conclusion which harmonizes    
with the theory long held by many       
chemists1 that hydrogen gas is the vapor
 of a very volatile metal4 ,this        
element1 however1 when combined with    
palladium1 is in a peculiarly active    
state1 which sustains somewhat the same 
relation to the familiar gas that ozone 
bears to ordinary oxygen4 ,hence ,graham
 distinguished this condition of        
hydrogen by the term hydrogenium4       
,shortly before his death a medal was   
struck at the ,royal ,mint from the     
hydrogen palladium alloy in honor of its
 discovery2 but1 although this discovery

 attracted public attention chiefly on  
account of the singular chemical        
relations of hydrogen1 which it brought 
so prominently to notice1 it will be    
remembered in the history of science    
rather as the beautiful termination of a
 life-long investigation1 of which the  
medal was the appropriate seal4         
,simultaneously with the experiments on 
gases1 whose results we have endeavored 
to present in the preceding pages1      
,graham carried forward a parallel line 
of investigation of an allied class of  
phenomena1 which may be regarded as the 
manifestations of molecular motion in   
liquid bodies4 ,the phenomena of        
diffusion reappear in liquids1 and      
,graham carefully observed the times in 
which equal weights of various salts    
dissolved in water diffused from an     
open-mouth bottle into a large volume of
 pure water1 in which the bottle was    
immersed4 ,he was not1 however1 able to 
correlate the results of these          
experiments by such a simple law as that

 which obtains with gases4 ,it appeared1
 nevertheless1 that the rate of         
diffusion differs very greatly for the  
different soluble salts1 having some    
relation to the chemical composition of 
the salt which he was unable to         
discover4 ,but he found it possible to  
divide the salts into groups of         
equi-diffusive substances1 and he showed
 that the rate of diffusion of the      
several groups bear to one another      
simple numerical ratios4  ,more         
important results were obtained from the
 study of a class of phenomena          
corresponding to the transpiration of   
gases through ,india-rubber or metallic 
septa4 ,these phenomena1 as manifested  
in the transfer of liquids and of salts 
in solution through bladder or a similar
 membrane1 had previously been          
frequently studied under the names of   
exosmose and endosmose1 but to ,graham  
we owe the first satisfactory           
explanation4 ,as in the case of gases1  
he referred these effects to the        

influence of chemical force1 combination
 taking place on one surface of the     
membrane and the compound breaking up on
 the other1 the difference depending1 as
 in the previous instance1 on the       
influence of mass4 ,he also swept away  
the arbitrary distinctions made by      
previous experimenters1 showed that this
 whole class of phenomena are           
essentially similar1 and called this    
manifestation of power simply osmose4   
,while studying osmotic action1 ,graham 
was led to one of his most important    
generalizations--the recognition of the 
crystalline and amorphous states as     
fundamental distinctions in chemistry4  
,bodies in the first state he called    
crystalloids2 those in the last state1  
colloids 7resembling glue74 ,that there 
is a difference in structure between    
crystalloids1 like sugar or felspar1 and
 colloids1 like barley candy or glass1  
has of course always been evident to the
 most superficial observer2 but ,graham 
was the first to recognize in these     

external differences two fundamentally  
distinct conditions of matter not       
peculiar to certain substances1 but     
underlying all chemical differences1 and
 appearing to a greater or less degree  
in every substance4 ,he showed that the 
power of diffusion through liquids      
depends very much on these fundamental  
differences of condition--sugar1 one of 
the least diffusible of the             
crystalloids1 diffusing fourteen times  
more rapidly than caromel1 the          
corresponding colloid4 ,he also showed  
that1 in accordance with the general    
chemical rule1 while colloids readily   
combine with crystalloids1 bodies in the
 same condition manifest little or no   
tendency to chemical union4 ,hence1 in  
osmose1 where the membranes employed are
 invariably colloidal1 the osmotic      
action is confined almost entirely to   
crystalloids1 since they alone are      
capable of entering into that           
combination with the material of the    
septum on which the whole action        

depends4  ,on the above principles      
,graham based a simple method of        
separating crystalloids from colloids1  
which he calls dialysis1 and which was a
 most valuable addition to the means of 
chemical analysis4 ,a shallow tray1     
prepared by stretching parchment paper  
7an insoluble colloid7 over a           
gutta-percha hoop1 is the only apparatus
 required4 ,the solution to be dialyzed 
is poured into this tray1 which is then 
floated on pure water1 whose volume     
should be eight or ten times greater    
than that of the solution4 ,under these 
conditions the crystalloids will diffuse
 through the porus septum into the      
water1 leaving the colloids on the tray1
 and in the course of a few days a more 
or less complete separation of the two  
classes of bodies will have taken place4
 ,in this way arsenious acid and similar
 crystalloids may be separated from the 
colloidal materials with which1 in the  
case of poisoning1 they are usually     
found mixed in the animal juices or     

tissues4  ,but1 besides having these    
practical applications1 the method of   
dialysis in the hands of ,graham yielded
 the most startling results1 developing 
an almost entirely new class of bodies1 
as the colloidal forms of our most      
familiar substances1 and justifying the 
conclusion that the colloidal as well as
 the crystalline condition is an almost 
universal attribute of matter4 ,thus1 he
 was able to obtain solutions in water  
of the colloidal states of aluminic1    
ferric1 chromic1 stannic1 metastannic1  
titanic1 molybdic1 tungstic1 and silicic
 hydrates1 all of which gelatinize under
 definite conditions like a solution of 
glue4 ,the wonderful nature of these    
facts can be thoroughly appreciated only
 by those familiar with the subject1 but
 all may understand the surprise with   
which the chemist saw such hard1        
insoluble bodies as flint dissolved     
abundantly in water and converted into  
soft jellies4 ,these facts are1 without 
doubt1 the most important contributions 

of ,dr4 ,graham to pure chemistry4  ,in 
this sketch of the scientific career of 
our late associate1 we have followed the
 logical1 rather than the chronological1
 order of events1 hoping thus to render 
the relations of the different parts of 
his work more intelligible4 ,it must be 
remembered1 however1 that the two lines 
of investigation we have distinguished  
were in fact inter-woven1 and that the  
beautiful harmony which his completed   
life presents was the result1 not of a  
preconceived plan1 but of a constant    
devotion to truth1 and a childlike      
faith1 which unhesitatingly pressed     
forward whenever nature pointed out the 
way4  ,although the investigations of   
the phenomena connected with the        
molecular motion in gases and liquids   
were by far the most important of ,dr4  
,graham's labors1 he also contributed to
 chemistry many researches which can not
 be included under this head4 ,of these1
 which we may regard as his detached    
efforts1 the most important was his     

investigation of the hydrates and other 
salts of phosphorus4 ,it is true that   
the interpretation he gave of the       
results has been materially modified by 
the modern chemical philosophy1 yet the 
facts which he established form an      
important part of the basis on which    
that philosophy rests4 ,indeed1 it seems
 as if he almost anticipated the later  
doctrines of types and polybasic acids1 
and in none of his work did he show more
 discriminating observation or acute    
reasoning4 ,a subsequent investigation  
on the condition of water in several    
crystalline salts and in the hydrates of
 sulphuric acid is equally remarkable4  
,lastly1 ,graham also made interesting  
observations on the combination of      
alcohol with salts1 on the process of   
etherification1 on the slow oxidation of
 phosphorus1 and on the spontaneous     
inflammability of phosphureted hydrogen4
 ,it would not1 however1 be appropriate 
in this place to do more than enumerate 
the subjects of these less important    

studies2 and we have therefore only     
aimed in this sketch to give a general  
view of the character of the field which
 this eminent student of nature chiefly 
cultivated1 and to show how abundant was
 the harvest of truth which we owe to   
his faithful toil4  ,graham was not a   
voluminous writer4 ,his scientific      
papers were all very brief1 but         
comprehensive1 and his ,elements of     
,chemistry was his only large work4     
,this was an admirable exposition of    
chemical physics1 as well as of pure    
chemistry1 and gave a more philosophical
 account of the theory of the galvanic  
battery than had previously appeared4   
,our late associate was fortunate in    
receiving during life a generous        
recognition of the value of his labors4 
,his membership was sought by almost all
 the chief scientific societies of the  
world1 and he enjoyed to a high degree  
the confidence and esteem of his        
associates4 ,indeed1 he was singularly  
elevated above the petty jealousies and 

belittling quarrels which so often mar  
the beauty of a student's life1 while   
the great loveliness and kindliness of  
his nature closely endeared him to his  
friends4  ,in concluding1 we must not   
forget to mention that most genial trait
 of ,graham's character1 his sympathy   
with young men1 which gave him great    
influence as a teacher in the college   
with which he was long associated4      
,there are many now prominent in the    
scientific world who have found in his  
encouragement the strongest incentive to
 perseverance1 and in his approval and  
friendship the best reward of success4  
,,vi4  ,,memoir ,,of ,,william          
,,hallowes ,,miller4      ,reprinted    
from the ,proceedings of the ,american  
,academy of     ,arts and ,sciences1    
,vol4 ,,xvi1 ,may #bd1 #ahha4   ,william
 ,hallowes ,miller1 who was elected     
,foreign ,honorary ,member of this      
,academy in the place of ,c4 ,f4        
,naumann1 ,may #bf1 #ahgd1 died at his  
residence in ,cambridge1 ,england1 on   

the #bjth of ,may1 #ahhj1 at the age of 
seventy-nine1 having been born at       
,velindre1 in ,wales1 ,april #e1 #ahja4 
,his life was singularly uneventful1    
even for a scholar4 ,graduating with    
mathematical honors at ,cambridge in    
#ahbf1 he became a fellow of his college
 7,st4 ,john's7 in #ahbi1 and was       
elected ,professor of ,mineralogy in the
 ,university in #ahcb4 ,under the       
influence of the calm and elegant       
associations of this ancient ,english   
university1 ,miller passed a long and   
tranquil life--crowded with useful      
labors1 honored by the respect and love 
of his associates1 and blessed by       
congenial family ties4 ,this quiet      
student-life was exactly suited to his  
nature1 which shunned the bustle and    
unrest of our modern world4 ,for        
relaxation1 even1 he loved to seek the  
retired valleys of the ,eastern ,alps2  
and the description which he once gave  
to the writer1 of himself sitting at the
 side of his wife amid the grand        

scenery1 intent on developing           
crystallographic formulae1 while the    
accomplished artist traced the          
magnificent outlines of the ,dolomite   
mountains1 was a beautiful idyl of      
science4  ,miller's activities1 however1
 were not confined to the ,university4  
,in #ahch he became a ,fellow of the    
,royal ,society1 and in #ahef he was    
appointed its ,foreign ,secretary--a    
post for which he was eminently fitted1 
and which he filled for many years4 ,in 
#ahdc he was selected one of a committee
 to superintend the construction of the 
new ,parliamentary standards of length  
and weight1 to replace those which had  
been lost in the fire which consumed the
 ,houses of ,parliament in #ahcd1 and to
 ,professor ,miller was confided the    
construction of the new standard of     
weight4 ,his work on this important     
committee1 described in an extended     
paper published in the ,philosophical   
,transactions for #ahef1 was a model of 
conscientious investigation and         

scientific accuracy4 ,professor ,miller 
was subsequently a member of a new      
,royal ,commission for examining into   
and reporting on the state of the       
secondary standards1 and for considering
 every question which could affect the  
primary1 secondary1 and local standards2
 and in #ahgj he was appointed a member 
of the ,commission ,internationale du   
,metre4 ,his services on this commission
 were of great value1 and it has been   
said that there was no member whose     
opinions had greater weight in          
influencing a decision upon any         
intricate and delicate question4        
,valuable1 however1 as were ,professor  
,miller's public services on these      
various commissions1 his chief work was 
at the ,university4 ,his teacher1 ,dr4  
,william ,whewell--afterward the ,master
 of ,trinity ,college--was his immediate
 predecessor in the ,professorship of   
,mineralogy at ,cambridge4 ,this great  
scholar1 whose encyclopaedic mind could 
not long be confined in so narrow a     

field1 held the professorship only four 
years2 but during this period he devoted
 himself with his usual enthusiasm to   
the study of crystallography1 and he    
accomplished a most important work in   
attracting to the same study young      
,miller1 who brought his mathematical   
training to its elucidation4 ,it was the
 privilege of ,professor ,miller to     
accomplish a unique work1 for the like  
of which a more advanced science1 with  
its multiplicity of details1 will offer 
few opportunities4  ,the foundations of 
crystallography had been laid long      
before ,miller's time4 ,hauey is usually
 regarded as the founder of the science2
 for he first discovered the importance 
of cleavage1 and classed the known facts
 under a definite system4 ,taking       
cleavage as his guide1 and assuming that
 the forms of cleavage were not only the
 primitive forms of crystals as a whole1
 but also the forms of their integrant  
molecules1 he endeavored to show that   
all secondary forms might be derived    

from a few primary forms1 regarded as   
elements of nature1 by means of         
decrements of molecules at their edges4 
,in like manner he showed that all the  
forms of a given mineral1 like          
fluor-spar or calcite1 might be built up
 from the integrant molecules by        
skillfully placing together the         
primitive forms4 ,hauey's dissection of 
crystals1 in a manner which appeared to 
lead to their ultimate crystalline      
elements1 gained for his system great   
popular attention and applause4 ,the    
system was developed with great         
perspicuity and completeness in a work  
remarkable for the vivacity of its style
 and the felicity of its illustration4  
,moreover1 a simple mathematical        
expression was given to the system1 and 
the notation which ,hauey invented to   
express the relation of the secondary to
 the primary forms1 as modified and     
improved by ,levy1 is still used by the 
,french mineralogists4  ,the system of  
,hauey1 however1 was highly artificial1 

and only prepared the way for a simpler 
and more general expression of the      
facts4 ,the ,german crystallographer1   
,weiss1 seems to be the first to have   
recognized the truth that the decrements
 of ,hauey were merely a mechanical mode
 of representing the fact that all the  
secondary faces of a crystal make       
intercepts on the edges of the primitive
 form which are simple multiples of each
 other2 and1 this general conception    
once gained1 it was soon seen that these
 ratios could be as simply measured on  
the axes of symmetry of the crystal as  
on the edges of the fundamental forms2  
and1 moreover1 that1 when crystal forms 
are viewed in their relation to these   
axes1 a more general law becomes        
evident1 and the artificial distinction 
between primary and secondary forms     
disappears4  ,thus became slowly evolved
 the conception of a crystal as a group 
of similar planes symmetrically disposed
 around certain definite and obvious    
systems of axes1 and so placed that the 

intercepts1 or parameters1 on these axes
 bore to each other a simple numerical  
ratio4 ,representing by a3b3c the ratio 
of the intercepts of a plane on the     
three axes of a crystal of a given      
substance1 then the intercepts of every 
other plane of this1 or of any other    
crystal of the same substance1 conform  
to the general proportion m4a3n4b3p4c1  
in which m1 n1 p are three simple whole 
numbers4 ,this simple notation1 devised 
by ,weiss1 expressed the fundamental law
 of crystallography2 and the conception 
of a crystal as a system of planes1     
symmetrically distributed according to  
this law1 was a great advance beyond the
 decrements of ,hauey1 an advance not   
unlike that of astronomy from the system
 of vortices to the law of gravitation4 
,yet1 as the mechanism of vortices was a
 natural prelude to the law of ,newton1 
so the decrements of ,hauey prepared the
 way for the wider views of the ,german 
crystallographers4  ,whether ,weiss or  
,mohs contributed most to advance       

crystallography to its more             
philosophical stage1 it is not important
 here to inquire4 ,each of these eminent
 scholars did an important work in      
developing and diffusing the larger     
ideas1 and in showing by their          
investigations that the facts of nature 
corresponded to the new conceptions4    
,but to ,carl ,friedrich ,naumann1      
,professor at the time in the           
,bergakademie zu ,freiberg1 belongs the 
merit of first developing a complete    
system of theoretical crystallography   
based on the laws of symmetry and axial 
ratios4 ,his ,lehrbuch der reinen und   
angewandten ,krystallographie1 published
 in two volumes at ,leipzig in #ahcj1   
was a remarkable production1 and seemed 
to grasp the whole theory of the        
external forms of crystals4 ,naumann    
used the obvious and direct methods of  
analytical geometry to express the      
quantitative relations between the parts
 of a crystal2 and1 although his methods
 are often unnecessarily prolix and his 

notation awkward1 his formulae are well 
adapted to calculation1 and easily      
intelligible to persons moderately      
disciplined in mathematics4  ,but1      
however comprehensive and perfect in its
 details1 the system of ,naumann was    
cumbrous1 and lacked elegance of        
mathematical form4 ,this arose chiefly  
from the fact that the old methods of   
analytical geometry were unsuited to the
 problems of crystallography2 but it    
resulted also from a habit of the       
,german mind to dwell on details and    
give importance to systems of           
classification4 ,to ,naumann the six    
crystalline systems were as much        
realities of nature as were the forms of
 the integrant molecules to ,hauey1 and 
he failed to grasp the larger thought   
which includes all partial systems in   
one comprehensive plan4  ,our late      
colleague1 ,professor ,miller1 on the   
other hand1 had that power of           
mathematical generalization which       
enabled him to properly subordinate the 

parts to the whole1 and to develop a    
system of mathematical crystallography  
of such simplicity and beauty of form   
that it leaves little to be desired4    
,this was the great work of his life1   
and a work worthy of the university     
which had produced the ,principia4 ,it  
was published in #ahci1 under the title1
 ,a ,treatise on ,crystallography2 and  
in #ahfc the substance of the work was  
reproduced in a more perfect form1 still
 more condensed and generalized1 in a   
thin volume of only eighty-six pages1   
which the author modestly called1 ,a    
,tract on ,crystallography4  ,miller    
began his study of crystallography with 
the same materials as ,naumann2 but1 in 
addition1 he adopted the beautiful      
method of ,franz ,ernst ,neumann of     
referring the faces of a crystal to the 
surface of a circumscribed sphere by    
means of radii drawn perpendicular to   
the faces4 ,the points where the radii  
meet the spherical surface are the poles
 of the faces1 and the arcs of great    

circles connecting these poles may      
obviously be used as a measure of the   
angles between the crystal faces4 ,this 
invention of ,neumann's was the germ of 
,miller's system of crystallography1 for
 it enabled the ,english mathematician  
to apply the elegant and compendious    
methods of spherical trigonometry to the
 solution of crystallographic problems2 
and ,professor ,miller always expressed 
his great indebtedness to ,neumann1 not 
only for this simple mode of defining   
the position of the faces of a crystal1 
but also for his method of representing 
the relative position of the poles of   
the faces on a plane surface by a       
beautiful application of the methods of 
stereo-graphic and gnomonic projection4 
,this method of representing a crystal  
shows very clearly the relations of the 
parts1 and was undoubtedly of great aid 
to ,miller in assisting him to          
generalize his deductions4  ,from the   
outset1 ,professor ,miller apprehended  
more clearly than any previous writer   

the all-embracing scope of the great law
 of crystallography4 ,he opens his      
treatise with its enunciation1 and1 from
 this law as the fundamental principle  
of the subject1 the whole of his system 
of crystallography is logically         
developed4 ,beyond this1 all that is    
peculiar to ,miller's system is involved
 in two or three general theorems4 ,the 
rest of his treatise consists of        
deductions from these principles and    
their application to particular cases4  
,one of the most important of these     
principles1 and one which in the        
treatise is involved in the enunciation 
of the fundamental law of               
crystallography1 is in its essence      
nothing but an analytical device4 ,as we
 have already stated1 ,weiss had shown  
that1 if a3b3c represent the ratio of   
the intercepts of any plane of a crystal
 on the three axes x1 y1 and z1         
respectively1 the intercepts of any     
other possible plane must satisfy the   
proportion--    ,a3,b3,c  m4a3n4b3p4c1  

in which m1 n1 and p are simple whole   
numbers4 ,the irrational values a1 b1   
and c are fundamental magnitudes for    
every crystalline substance2,g and      
,miller called these relative magnitudes
 the parameters of the crystals1 while  
he called the whole numbers1 m1 n1 and  
p1 the indices of the respective planes4
 ,but1 instead of writing the proportion
 which expresses the law of             
crystallography as above1 he gave to it 
a slightly different form1 thus3        
,a3,b3,c                                
7#a_/;h74a37#a_/k74b37#a_/l74c1  and    
used in his system for the indices of a 
plane the values h3k3l1 which are also  
in the ratio of whole numbers1 and      
usually of simpler whole numbers than   
m3n3p4 ,this seems a small difference2  
for h k l in the last proportion are    
obviously the reciprocals of m n p in   
the first2 but the difference1 small as 
it is1 causes a wonderful simplification
 of the formulae which express the      
relations between the parts of a        

crystal4 ,from the last proportion we   
derive at once    7#a_/;h747a_/,a7      
7#a_/k747b_/,b7  7#a_/l747c_/,c71  which
 is the form in which ,miller stated his
 fundamental law4    ,g ,for example1   
the native crystals         of sulphur  
have                a3b3c               
#a3b4cdj3a4bcc4       ,crystals of      
gypsum have          a3b3c              
#a3j4dac3j4fia4       ,crystals of      
tin-stone have       a3b3c  #a3a3j4fgbd4
       ,and crystals of common salt have
 a3b3c  #a3a3a4  ,if ,p represents the  
pole of a face whose indices are h k l1 
that is1 represents the point where the 
radius drawn normal to the face meets   
the surface of the sphere circumscribed 
around the crystal 7the sphere of       
projection1 as it is called71 and if ,x1
 ,y1 ,z represent the points where the  
axes of the crystal meet the same       
spherical surface1,h then it is evident 
that ,x ,y1 ,x ,z1 and ,y ,z are the    
arcs of great circles1 which measure the
 inclination of the axes to each other1 

and that ,p ,x1 ,p ,y1 and ,p ,z are    
arcs of other great circles1 which      
measure the inclination of the plane 7h 
k l7 on planes normal to the respective 
axes2 and1 also1 that these several arcs
 form the sides of spherical triangles  
thus drawn on the sphere of projection4 
,now1 it is very easily shown that      
7a_/h74cos ,p ,x  7b_/k74cos ,p ,y      
7c_/l74cos ,p ,z2  and by means of this 
theorem we are able to reduce a great   
many problems of crystallography to the 
solution of spherical triangles4    ,h  
,the origin of the axes is always taken 
as the center of the       sphere of    
projection4  ,another very large class  
of problems in crystallography is based 
on the relation of faces in a zone2 that
 is1 of faces which are all parallel to 
one line called the zone axis1 and whose
 mutual intersections1 therefore1 are   
all parallel to each other4 ,if1 now1 h 
k l and p q r are the indices of any two
 planes of a zone 7not parallel to each 
other71 any other plane in the same zone

 must fulfill the condition expressed by
 the simple equation    u4u  v4v  w4w   
o1  where u v and w are the indices of  
the third plane1 and u v w have the     
values    u  k4r - l4q   v  l4p - h4r   
w  h4q - k4p4  ,since h k l and p q r   
are whole numbers1 it is evident that u 
v w must also be whole numbers1 and     
these quantities are called the indices 
of the zone4 ,the three whole numbers   
which are the indices of a plane when   
written in succession serve as a very   
convenient symbol of that plane1 and    
represent to the crystallographer all   
its relations2 and in like manner       
,miller used the indices of a zone      
inclosed in brackets as the symbol of   
that zone4 ,thus #abc1 #eca1 #jaj are   
symbols of planes1 and #aaa1 #bac1 #jja 
symbols of zones4  ,an additional       
theorem enables us to calculate the     
symbols of a fourth plane in a zone when
 the angular distances between the four 
planes and the symbols of three of them 
are known1 but this problem can not be  

made intelligible with a few words4     
,the few propositions to which we have  
referred involve all that is essential  
and peculiar to the system of ,professor
 ,miller4 ,these given1 and the rest    
could be at once developed by any       
scholar who was familiar with the facts 
of crystallography2 and the circumstance
 that its essential features can be so  
briefly stated is sufficient to show how
 exceedingly simple the system is4 ,at  
the same time1 it is wonderfully        
comprehensive1 and the student who has  
mastered it feels that it presents to   
him in one grand view the entire scheme 
of crystal forms1 and that it greatly   
helps him to comprehend the scheme as a 
whole1 and not simply as the sum of     
certain distinct parts4 ,so felt        
,professor ,miller himself2 and1 while  
he regarded the six systems of crystals 
of the ,german crystallographers as     
natural divisions of the field1 he      
considered that they were bounded by    
artificial lines which have no deeper   

significance than the boundary lines on 
a map4 ,how great the unfolding of the  
science from ,hauey to ,miller1 and yet 
now we can see the great fundamental    
ideas shining through the obscurity from
 the first6 ,what we now call the       
parameters of a crystal were to ,hauey  
the fundamental dimensions of his       
integrant molecules1 our indices were   
his decrements1 and our conceptions of  
symmetry his fundamental forms4 ,there  
has been nothing peculiar1 however1 in  
the growth of crystallography4 ,this    
growth has followed the usual order of  
science1 and here as elsewhere the      
early1 gross1 material conceptions have 
been the stepping-stones by which men   
rose to higher things4 ,in sciences like
 chemistry1 which are obviously still in
 the earlier stages of their            
development1 it would be well if        
students would bear in mind this truth  
of history1 and not attach undue        
importance to structural formulae and   
similar mechanical devices1 which1      

although useful for aiding the memory1  
are simply hindrances to progress as    
soon as the necessity of such assistance
 is passed4 ,and1 when the life of a    
great master of science has ended1 it is
 well to look back over the road he has 
traveled1 and1 while we take courage in 
his success1 consider well the lesson   
which his experience has to teach2 and1 
as progress in this world's knowledge   
has ever been from the gross to the     
spiritual1 may we not rejoice as those  
who have a great hope8  ,although the   
exceeding merit of the ,treatise on     
,crystallography casts into the shade   
all that was subordinate1 we must not   
omit to mention that ,professor ,miller 
published an early work on hydrostatics1
 and numerous shorter papers on         
mineralogy and physics1 which were all  
valuable1 and constantly contained      
important additions to knowledge4       
,moreover1 the ,new ,edition of         
,phillips's ,mineralogy1 which he       
published in #aheb in connection with   

,h4 ,j4 ,brooke1 owed its chief value to
 a mass of crystallographic observations
 which he had made with his usual       
accuracy and patience during many years1
 and there tabulated in his concise     
manner4 ,as has been said by one of his 
associates in the ,royal ,society1 it is
 a monument to ,miller's name1 although 
he almost expunged that name from it4,i 
,it is due to ,professor ,miller's      
memory that his works should be         
collated1 and especially that by a      
suitable commentary his ,tract on       
,crystallography should be made         
accessible to the great body of the     
students of physical science1 who have  
not1 as a rule1 the ability or training 
which enables them to apprehend a       
generalization when solely expressed in 
mathematical terms4 ,the very merits of 
,professor ,miller's book as a          
scientific work render it very difficult
 to the average student1 although it    
only involves the simplest forms of     
algebra and trigonometry4    ,i         

,obituary ,notices from the ,proceedings
 of the ,royal ,society1       ,no4     
#bjf1 #ahhj1 to which the writer has    
been indebted for       several         
biographical details4  ,independence1   
breadth1 accuracy1 simplicity1 humility1
 courtesy1 are luminous words which     
express the character of ,professor     
,miller4 ,in his genial presence the    
young student felt encouraged to express
 his immature thoughts1 which were sure 
to be treated with consideration1 while 
from a wealth of knowledge the great    
master made the error evident by making 
the truth resplendent4 ,it was the      
greatest satisfaction to the            
inexperienced investigator when his     
observations had been confirmed by      
,professor ,miller1 and he was never    
made to feel discouraged when his       
mistakes were corrected4 ,the writer of 
this notice regards it as one of the    
great privileges of his youth1 and one  
of the most important elements of his   
education1 to have been the recipient of

 the courtesies and counsel of three    
great ,english men of science1 who have 
always been his own ideal knights1 and  
these noble knights were ,faraday1      
,graham1 and ,miller4     ,,vii4        
,,william ,,barton ,,rogers4   ,william 
,barton ,rogers was born at             
,philadelphia1 on the #gth of ,december1
 #ahjd4 ,his father1 ,patrick ,kerr     
,rogers1 was a native of ,newton        
,stewart1 in the north of ,ireland2 but 
while a student at ,trinity ,college1   
,dublin1 becoming an object of suspicion
 on account of his sympathy with the    
,rebellion of #agih1 he emigrated to    
this country1 and finished his education
 in the ,university of ,pennsylvania1 at
 ,philadelphia1 where he received the   
degree of ,doctor of ,medicine4  ,here  
he married ,hannah ,blythe1 a ,scotch   
lady--who was at the time living with   
her aunt1 ,mrs4 ,ramsay--and settled    
himself in his profession in a house on 
,ninth ,street1 opposite to the         
,university2 and in this house ,william 

,b4 ,rogers was born4 ,he was the second
 of four sons--,james1 ,william1 ,henry1
 and ,robert--all of whom became        
distinguished as men of science4        
,patrick ,kerr ,rogers1 finding that his
 prospects of medical practice in       
,philadelphia had been lessened in      
consequence of a protracted absence in  
,ireland1 made necessary by the death of
 his father1 removed to ,baltimore2 but 
soon afterward accepted the             
,professorship of ,chemistry and        
,physics in ,william and ,mary ,college1
 ,virginia1 made vacant by the          
resignation of the late ,robert ,hare2  
and it is a fact worthy of notice that1 
while he succeeded ,dr4 ,hare at        
,william and ,mary ,college1 his eldest 
son1 ,james1 succeeded ,dr4 ,hare at the
 ,university of ,pennsylvania4 ,at      
,william and ,mary ,college the four    
brothers ,rogers were educated2 and on  
the death of the father1 at ,ellicott   
,mills1 in #ahbh1 ,william ,b4 ,rogers  
succeeded to the professorship thus made

 vacant4  ,he had already earned a      
reputation as a teacher by a course of  
lectures before the ,maryland ,institute
 in ,baltimore during the previous year1
 and after his appointment at once      
entered on his career as a scientific   
investigator4 ,at this period he        
published a paper on ,dew1 and1 in      
connection with his brother ,henry1     
another paper on the ,voltaic           
,battery--both subjects directly        
connected with his professorship4 ,but  
his attention was early directed to     
questions of chemical geology2 and he   
wrote1 while at ,william and ,mary      
,college1 a series of articles for the  
,farmer's ,register on the ,green ,sands
 and ,marls of ,eastern ,virginia1 and  
their value as fertilizers4 ,next we    
find the young professor going before   
the ,legislature of ,virginia1 and1     
while modestly presenting his own       
discoveries1 making them the occasion   
for urging upon that body the importance
 of a systematic geological survey for  

developing the resources of the ,state4 
,so great was the scientific reputation 
that ,professor ,rogers early acquired  
by such services1 that in #ahce he was  
called to fill the important            
,professorship of ,natural ,philosophy  
and ,geology in the ,university of      
,virginia2 and during the same year he  
was appointed ,state ,geologist of      
,virginia1 and began those important    
investigations which will always        
associate his name with ,american       
geology4  ,professor ,rogers remained at
 the head of the ,geological ,survey of 
,virginia until it was discontinued1 in 
#ahdb1 and published a series of very   
valuable annual reports4 ,as was        
anticipated1 the survey led to a large  
accumulation of material1 and to        
numerous discoveries of great local     
importance4 ,as this was one of the     
earliest geological surveys undertaken  
in the ,united ,states1 its directors   
had in great measure to devise the      
methods and lay out the plans of        

investigation which have since become   
general4 ,this is not the place1        
however1 for such details2 but there are
 four or five general results of        
,professor ,rogers's geological work at 
this period which have exerted a        
permanent influence on geological       
science1 and which should therefore be  
briefly noticed4 ,some of these results 
were first published in the ,american   
,journal of ,science2 others were       
originally presented to the ,association
 of ,american ,geologists and           
,naturalists1 and published in its      
,transactions4 ,professor ,rogers took a
 great interest in the organization of  
this association in #ahdj1 presided over
 its meeting in #ahde1 and again1 two   
years later1 when it was expanded into  
the ,american ,association for the      
,advancement of ,science4  ,in          
connection with his brother ,robert1    
,professor ,william ,b4 ,rogers was the 
first to investigate the solvent action 
of water--especially when charged with  

carbonic acid--on various minerals and  
rocks2 and by showing the extent of this
 action in nature1 and its influence in 
the formation of mineral deposits of    
various kinds1 he was one of the first  
to observe and interpret the important  
class of facts which are the basis of   
chemical geology4  ,another important   
result of ,professor ,rogers's          
geological work was to show that the    
condition of any coal-bed stands in a   
close genetic relation to the amount of 
disturbance to which the enclosing      
strata have been submitted1 the coal    
becoming harder and containing less     
volatile matter as the evidence of      
disturbance increases4 ,this            
generalization1 which seems to us now   
almost self-evident--understanding1 as  
we do1 more of the history of the       
formation of coal--was with ,professor  
,rogers an induction from a great mass  
of observed facts4  ,by far1 however1   
the most memorable contribution of      
,professor ,rogers to geology was that  

made in connection with ,henry ,d4      
,rogers1 in a paper entitled ,the ,laws 
of ,structure of the more ,disturbed    
,zones of the ,earth's ,crust1 presented
 by the two brothers at the meeting of  
the ,association of ,american           
,geologists and ,naturalists1 held at   
,boston in #ahdb4 ,this paper was the   
first presentation of what may be called
 in brief the ,wave ,theory of ,mountain
 ,chains4 ,this theory was deduced by   
the brothers ,rogers from an extended   
study of the ,appalachian ,chain in     
,pennsylvania and ,virginia1 and was    
supported by numerous geological        
sections and by a great mass of facts4  
,the hypothesis which they offered as an
 explanation of the origin of the great 
mountain waves may not be generally     
received2 but the general fact1 that the
 structure of mountain chains is alike  
in all the essential features which the 
brothers ,rogers first pointed out1 has 
been confirmed by the observations of   
,murchison in the ,ural1 of ,darwin in  

the ,andes1 and of the ,swiss geologists
 in the ,alps4 ,in the ,appalachians the
 wave structure is very simple1 and the 
same is true in all corrugated districts
 where the crust movements have been    
simple1 and have acted in one direction 
only4 ,but where the elevating forces   
have acted in different directions at   
different times1 causing interference of
 waves like a chopped sea1 as in the    
,swiss ,alps and the mountains of ,wales
 or ,cumberland1 the undulations are    
disguised1 and are with extreme         
difficulty made out4 ,the wave theory of
 mountain chains was the first important
 contribution to dynamical and          
structural geology which had been       
brought forward in this country4 ,it    
excited at the time great interest1 as  
well from the novelty of the views as   
from the eloquence with which they were 
set forth2 and to-day it is still       
regarded as one of the most important   
advances in orographic geology4  ,a     
marked feature of mountain regions is   

that rupturing of the strata called     
faults2 and another of the striking     
geological generalizations of the       
brothers ,rogers is what may be called  
the law of the distribution of faults4  
,they showed that faults do not occur on
 gentle waves1 but in the most          
compressed flexures of the mountain     
chains1 which in the act of moving have 
snapped or given way at the summit where
 the bend is sharpest1 the less inclined
 side being shoved up on the plane of   
the fault1 this plane being generally   
parallel to1 if it does not coincide    
with1 the axis plane2 and1 further1 that
 the direction of these faults generally
 follows the run of the line of         
elevation of the mountains1 the length  
and vertical displacement depending on  
the strength of the disturbing force4   
,the last of the general geological     
results to which we referred above was  
published under the name of ,william ,b4
 ,rogers only4 ,it was based on the     
observed positions of more than fifty   

thermal springs in the ,appalachian     
belt1 occurring in an area of about     
fifteen thousand square miles1 which    
were shown to issue from anticlinal axes
 and faults1 or from points very near   
such lines2 and in connection with these
 springs it was further shown that there
 was a great preponderance of nitrogen  
in the gases which the waters held in   
solution4  ,it must be remembered that1 
during the time when this geological    
work was accomplished1 ,professor       
,rogers was an active teacher in the    
,university of ,virginia1 giving through
 a large part of the year almost daily  
lectures either on physics or geology4  
,those who met him in his after-life in 
various relations in ,boston1 and were  
often charmed by his wonderful power of 
scientific exposition1 can readily      
understand the effect he must have      
produced1 when in the prime of manhood1 
upon the enthusiastic youths who were   
brought under his influence4 ,his       
lecture-room was always thronged4 ,as   

one of his former students writes1 ,all 
the aisles would be filled1 and even the
 windows crowded from the outside4 ,in  
one instance ,i remember the crowd had  
assembled long before the hour named for
 the lecture1 and so filled the hall    
that the professor could only gain      
admittance through a side entrance      
leading from the rear of the hall       
through the apparatus-room4 ,these facts
 show how he was regarded by the        
students of the ,university of          
,virginia4 ,his manner of presenting the
 commonest subject in science--clothing 
his thoughts1 as he always did1 with a  
marvelous fluency and clearness of      
expression and beauty of diction--caused
 the warmest admiration1 and often      
aroused the excitable nature of         
,southern youths to the exhibition of   
enthusiastic demonstrations of          
approbation4 ,throughout ,virginia1 and 
indeed the entire ,south1 his former    
students are scattered1 who even now    
regard it as one of the highest         

privileges of their lives to have       
attended his lectures4  ,such was the   
impression which ,professor ,rogers left
 at the ,university of ,virginia1 that1 
when he returned1 thirty-five years     
later1 to aid in the celebration of the 
semi-centennial1 he was met with a      
perfect ovation4 ,although the memories 
of the civil war1 which had intervened1 
and ,professor ,rogers's known          
sympathies with the ,northern cause1    
might well have damped enthusiasm1 yet  
the presence of the highly honored      
teacher was sufficient to rekindle the  
former admiration2 and1 in the language 
of a contemporary ,virginia newspaper1  
the old students beheld before them the 
same ,william ,b4 ,rogers who           
thirty-five years before had held them  
spellbound in his class of natural      
philosophy2 and1 as the great orator    
warmed up1 these men forgot their age2  
they were again young1 and showed their 
enthusiasm as wildly as when1 in days of
 yore1 enraptured by his eloquence1 they

 made the lecture-room of the           
,university ring with their applause4   
,besides his geological papers1         
,professor ,rogers published1 while at  
the ,university of ,virginia1 a number  
of important chemical contributions1    
relating chiefly to new and improved    
methods in chemical analysis and        
research4 ,these papers were published  
in connection with his youngest brother1
 ,robert ,e4 ,rogers1 now become his    
colleague as ,professor of ,chemistry   
and ,materia ,medica in the ,university2
 and such were the singularly intimate  
relations between the brothers that it  
is often impossible to dissociate their 
scientific work4 ,among these were      
papers ,on a ,new ,process for obtaining
 ,pure ,chlorine2 ,a ,new ,process for  
obtaining ,formic ,acid1 ,aldehyde1     
etc42 ,on the ,oxidation of the ,diamond
 in the ,liquid ,way2 ,on ,new          
,instruments and ,processes for the     
,analysis of the ,carbonates2 ,on the   
,absorption of ,carbonic ,acid by       

,liquids2 besides the extended          
investigation ,on the ,decomposition of 
,minerals and ,rocks by ,carbonated and 
,meteoric ,waters1 to which we have     
referred above4 ,there was also at this 
time a large amount of chemical work    
constantly on hand in connection with   
the ,geological ,survey1 such as        
analyses of mineral waters1 ores1 and   
the like4 ,moreover1 while at the       
,university of ,virginia1 ,professor    
,rogers published a short treatise on   
,the ,strength of ,materials1 and a     
volume on ,the ,elements of             
,mechanics1--books which1 though long   
out of print1 were very useful          
text-books in their day1 and are marked 
by the clearness of style and felicity  
of explanation for which the author was 
so distinguished4  ,the year #ahec      
formed a turning-point in ,professor    
,rogers's life4 ,four years previously  
he had married ,miss ,emma ,savage1     
daughter of ,hon4 ,james ,savage1 of    
,boston1 the well-known author of the   

,new ,england ,genealogical ,dictionary1
 and ,president of the ,massachusetts   
,historical ,society4 ,this connection  
proved to be the crowning blessing of   
his life4 ,mrs4 ,rogers1 by her energy1 
her intelligence1 her cheerful          
equanimity1 her unfailing sympathy1     
became the promoter of his labors1 the  
ornament and solace of his middle life1 
and the devoted companion and support of
 his declining years4 ,immediately after
 his marriage1 ,june #bj1 #ahdi1 he     
visited ,europe with his wife1 and was  
present at the meeting of the ,british  
,association for the ,advancement of    
,science1 held that year at ,birmingham1
 where he was received with great       
warmth1 and made a most marked          
impression4 ,returning home in the      
autumn1 ,professor ,rogers resumed his  
work at the ,university of ,virginia2   
but the new family relations which had  
been established led in #ahec to the    
transfer of his residence to ,boston1   
where a quite different1 but even a more

 important1 sphere of usefulness        
surrounded him4 ,his wide scientific    
reputation1 as well as his family       
connection1 assured him a warm welcome  
in the most cultivated circles of       
,boston society1 where his strength of  
character1 his power of imparting       
knowledge1 and his genial manners1 soon 
commanded universal respect and         
admiration4 ,he at once took an active  
part in the various scientific interests
 of the city4 ,from #ahde he had been a 
,fellow of this ,academy2,j and after   
taking up his residence among us he was 
a frequent attendant at our meetings1   
often took part in our proceedings1     
became a member of our ,council1 and    
from #ahfc to #ahfi acted as our        
,corresponding ,secretary4 ,he took a   
similar interest in the ,boston ,society
 of ,natural ,history4 ,he was a member1
 and for many years the ,president1 of  
the ,thursday ,evening ,scientific      
,club1 to which he imparted new life and
 vigor1 and which was rendered by him an

 important field of influence4 ,the     
members who were associated with him in 
that club will never forget those       
masterly expositions of recent advances 
in physical science2 and will remember  
that1 while he made clear their         
technical importance to the wealthy     
business men around him1 he never failed
 to impress his auditors with the worth 
and dignity of scientific culture4    ,j
 ,this notice is reprinted from the     
,proceedings of the ,american           
,academy of ,arts and ,sciences1 vol4   
xviii1 #ahhb-'hc4  ,during the earlier  
years of his residence in ,boston1      
,professor ,rogers occupied himself with
 a number of scientific problems1       
chiefly physical4 ,he studied the       
variations of ozone 7or of what was then
 regarded as ozone7 in the atmosphere at
 the time when this subject was exciting
 great attention4 ,he was greatly       
interested in the improvements of the   
,ruhmkorff ,coil made by ,mr4 ,e4 ,s4   
,ritchie2 and in this connection        

published a paper on the ,actinism of   
the ,electric ,discharge in ,vacuum     
,tubes4 ,a study of the phenomena of    
binocular vision led to a paper entitled
 ,experiments disproving by the         
,binocular ,combination of ,visual      
,spectra ,brewster's ,theory of         
,successive ,combinations of            
,corresponding ,points4 ,a paper        
discussing the phenomena of smoke rings 
and rotating rings in liquids appeared  
in the ,american ,journal of ,science   
for #aheh1 with the description of a    
very simple but effective apparatus by  
which the phenomena would be readily    
reproduced4 ,in this paper ,professor   
,rogers anticipated some of the later   
results of ,helmholtz and ,sir ,william 
,thomson4 ,in the same year an ingenious
 illustration of the properties of      
sonorous flames was exhibited to the    
,thursday ,evening ,club above          
mentioned1 in which ,professor ,rogers  
anticipated ,count ,schafgottsch in the 
invention of a beautiful optical proof  

of the discontinuity of the singing     
hydrogen flame4  ,in #ahfa ,professor   
,rogers accepted from ,governor ,andrew 
the office of ,inspector of ,gas and    
,gas-,meters for the ,state of          
,massachusetts1 and organized a system  
of inspection in which he aimed to apply
 the latest scientific knowledge to this
 work2 and in a visit he again made to  
,europe in #ahfd he presented1 at the   
meeting of the ,british ,association at 
,bath1 a paper entitled ,an ,account of 
,apparatus and ,processes for ,chemical 
and ,photometrical ,testing of          
,illuminating ,gas4  ,during this period
 he gave several courses of lectures    
before the ,lowell ,institute of        
,boston1 which were listened to with the
 greatest enthusiasm1 and served very   
greatly to extend ,professor ,rogers's  
reputation in this community4 ,night    
after night1 crowded audiences1         
consisting chiefly of teachers and      
working-people1 were spellbound by his  
wonderful power of exposition and       

illustration4 ,there was a great deal   
more in ,professor ,rogers's            
presentation of a subject than felicity 
of expression1 beauty of language1      
choice of epithets1 or significance of  
gesture4 ,he had a power of marshaling  
facts1 and bringing them all to bear on 
the point he desired to illustrate1     
which rendered the relations of his     
subject as clear as day4 ,in listening  
to this powerful oratory1 one only felt 
that it might have had1 if not a more   
useful1 still a more ambitious aim2 for 
less power has moved senates and        
determined the destinies of empires4    
,the interest in ,professor ,rogers's   
lectures was not excited solely1        
however1 by the charm of his eloquence2 
for1 although such was the felicity of  
his presentations1 and such the         
vividness of his descriptions1 that he  
could often dispense with the material  
aids so essential to most teachers1 yet 
when the means of illustration were at  
his command he showed his power quite as

 much in the adaptation of experiments  
as in the choice of language4 ,he well  
knew that experiments1 to be effective1 
must be simple and to the point2 and he 
also knew how to impress his audience   
with the beauty of the phenomena and    
with the grandeur of the powers of      
nature4 ,he always seemed to enjoy any  
elegant or striking illustration of a   
physical principle even more than his   
auditors1 and it was delightful to see  
the enthusiasm which he felt over the   
simplest phenomena of science when      
presented in a novel way4  ,we come now 
to the crowning and greatest work of    
,professor ,rogers's life1 the founding 
of the ,massachusetts ,institute of     
,technology--an achievement so important
 in its results1 so far-reaching in its 
prospects1 and so complete in its       
details1 that it overshadows all else4  
,a great preacher has said that every   
man's life is a plan of ,god's4 ,the    
faithful workman can only make the best 
use of the opportunities which every day

 offers2 but he may be confident that   
work faithfully done will not be for    
naught1 and must trustingly leave the   
issue to a higher power4 ,little did    
young ,rogers think1 when he began to   
teach in ,virginia1 that he was to be   
the founder of a great institution in   
the ,state of ,massachusetts2 and yet we
 can now see that the whole work of his 
life was a preparation for this noble   
destiny4 ,the very eloquence he so early
 acquired was to be his great tool2 his 
work on the ,geological ,survey gave him
 a national reputation which was an     
essential condition of success2 his life
 at the ,university of ,virginia1 where 
he was untrammeled by the traditions of 
the older universities1 enabled him to  
mature the practical methods of         
scientific teaching which were to       
commend the future institution to a     
working community2 and1 most of all1 the
 force of character and large humanity  
developed by his varied experience with 
the world were to give him the power1   

even in the conservative ,state of his  
late adoption1 to mold legislators and  
men of affairs to his wise designs4  ,it
 would be out of place1 as it would be  
unnecessary1 to dwell in this connection
 on the various stages in the           
development of the ,institute of        
,technology4 ,the facts are very        
generally known in this community1 and  
the story has been already well told4   
,the conception was by no means a sudden
 inspiration1 but was slowly matured out
 of a far more general and less specific
 plan1 originating in a committee of    
large-minded citizens of ,boston1 who1  
in #ahei1 and again in #ahfj1 petitioned
 the ,legislature of ,massachusetts to  
set apart a small portion of the land   
reclaimed from the ,back ,bay for the   
use of such scientific1 industrial1 and 
fine art institutions as may associate  
together for the public good4 ,the large
 scheme failed2 but from the failure    
arose two institutions which are the    
honor and pride of ,boston--the ,museum 

of ,fine ,arts and the ,institute of    
,technology4 ,in the further development
 of the ,museum of ,fine ,arts1         
,professor ,rogers had only a secondary 
influence2 but one of his memorials to  
the ,legislature contains a most        
eloquent statement1 often quoted1 of the
 value of the fine arts in education1   
which attests at once the breadth of his
 culture and the largeness of his       
sympathies4  ,although the committee of 
gentlemen above referred to had failed  
to carry out their general plan1 yet the
 discussions to which it gave rise had  
developed such an interest in the       
establishment of an institution to be   
devoted to industrial science and       
education that they determined upon     
taking the preliminary steps toward the 
organization of such an institution4 ,a 
sub-committee was charged with preparing
 a plan2 and the result was a document1 
written by ,professor ,rogers1 entitled 
,objects and ,plan of an ,institute of  
,technology4 ,that document gave birth  

to the ,massachusetts ,institute of     
,technology1 for it enlisted sufficient 
interest to authorize the committee to  
go forward4 ,a charter with a           
conditional grant of land was obtained  
from the ,legislature in #ahfa1 and the 
institution was definitely organized1   
and ,professor ,rogers appointed        
,president1 ,april #h1 #ahfb4 ,still1   
the final plans were not matured1 and it
 was not until ,may #cj1 #ahfd1 that the
 government of the new institution      
adopted the report prepared by its      
president1 entitled ,scope and ,plan of 
the ,school of ,industrial ,science of  
the ,massachusetts ,institute of        
,technology1 which ,dr4 ,runkle has     
called the intellectual charter of the  
institution1 and which he states has    
been followed in all essential points to
 this very day4 ,in striking            
confirmation of what we have written    
above1 ,dr4 ,runkle further says3  ,in  
this document we see more clearly the   
breadth1 depth1 and variety of          

,professor ,rogers's scientific         
knowledge1 and his large experience in  
college teaching and discipline4 ,it    
needed just this combination of         
acquirements and experience to put his  
conceptions into working shape1 to group
 together those studies and exercises   
which naturally and properly belong to  
each professional course1 and thus      
enable others to see the guiding-lines  
which must direct and limit their work  
in its relations to the demands of other
 departments4444  ,the experimental     
element in our school--a feature which  
has been widely recognized as           
characteristic--is undoubtedly due to   
the stress and distinctness given to it 
in the ',scope and ,plan4' ,in our      
discipline we must also give credit to  
the tact and large-heartedness of       
,professor ,rogers--in the fact that we 
are entirely free from all petty rules  
and regulations relating to conduct1    
free from all antagonism between        
teachers and students4  ,the associates 

of ,professor ,rogers in this           
,academy--many of them his associates   
also in the ,institute of ,technology1  
or in the ,society of ,arts1 which was  
so important a feature of the           
organization--will remember with what   
admiration they watched the             
indefatigable care with which its ever  
active president fostered the young life
 of the institution he had created4     
,they know how1 during the earlier      
years1 he bore the whole weight of the  
responsibility of the trust he had      
voluntarily and unselfishly assumed for 
the public good2 how1 while by his      
personal influence obtaining means for  
the daily support of the school1 he gave
 a great part of the instruction1 and   
extended a personal regard to every     
individual student committed to his     
charge4 ,they recall with what wisdom1  
skill1 tact1 and patience he directed   
the increasing means and expanding scope
 of the now vigorous institution1       
overcoming obstacles1 reconciling       

differences1 and ingratiating public    
favor4 ,they will never forget how1 when
 the great depression succeeded the     
unhealthy business activity caused by   
the civil war1 during which the         
institution had its rise1 the powerful  
influence of its great leader was able  
to conduct it safely through the        
financial storm4 ,they greatly grieved  
when1 in the autumn of #ahfh1 the great 
man who had accomplished so much1 but on
 whom so much depended1 his nerves      
fatigued by care and overwork1 was      
obliged to transfer the leadership to a 
younger man2 and ten years later were   
correspondingly rejoiced to see the     
honored chief come again to the front1  
with his mental power unimpaired1 and   
with adequate strength to use his       
well-earned influence to secure those   
endowments which the increased life of  
the institution required2 and they      
rejoiced with him when he was able to   
transfer to a worthy successor the      
completed edifice1 well established and 

equipped--an enduring monument to the   
nobility of character and the           
consecration of talents4 ,they have been
 present also on that last occasion1 and
 have united in the acclamation which   
bestowed on him the title ,founder and  
,father perpetual1 by a patent          
indefeasible4 ,they have heard his      
feeling but modest response1 and have   
been rejoicing though tearful witnesses 
when1 after the final seal of           
commendation was set1 he fell back1 and 
the great work was done4  ,we honor the 
successful teacher1 we honor the        
investigator of ,nature's laws1 we honor
 the upright director of affairs--and   
our late associate had all these claims 
to our regard2 but we honor most of all 
the noble manhood--and of such make are 
the founders of great institutions4 ,in 
comparison1 how empty are the ordinary  
titles of distinction of which most men 
are proud6 ,it seems now almost trivial 
to add that our associate was decorated 
with a ,doctor's degree1 both by his own

 university and also by the ,university 
at ,cambridge2 that he was sought as a  
member by many learned societies2 that  
he was twice called to preside over the 
annual meetings of the ,american        
,association for the ,advancement of    
,science2 and that1 at the death of     
,professor ,henry1 he was the one man of
 the country to whom all pointed as the 
,president of the ,national ,academy of 
,science4 ,this last honor1 however1 was
 one on which it is a satisfaction to   
dwell for a moment1 because it gave     
satisfaction to ,professor ,rogers1 and 
the office was one which he greatly     
adorned1 and for which his unusual      
oratorical abilities were so well       
suited4 ,he was a most admirable        
presiding officer of a learned society4 
,his breadth of soul and urbanity of    
manner insensibly resolved the discords 
which often disturb the harmonies of    
scientific truth4 ,he had the delicate  
tact so to introduce a speaker as to win
 in advance the attention of the        

audience1 without intruding his own     
personality2 and when a paper was read1 
and the discussion closed1 he would sum 
up the argument with such clearness1 and
 throw around the subject such a glow of
 light1 that abstruse results of        
scientific investigation were made clear
 to the general comprehension1 and a    
recognition gained for the author which 
the shrinking investigator could never  
have secured for himself4 ,to ,professor
 ,rogers the truth was always beautiful1
 and he could make it radiant4  ,it is  
also a pleasure to record1 in           
conclusion1 that ,professor ,rogers's   
declining years were passed in great    
comfort and tranquillity1 amidst all the
 amenities of life2 that to the last he 
had the companionship of her whom he so 
greatly loved2 and that increasing      
infirmities were guarded and the        
accidents of age warded off with a      
watchfulness that only the tenderest    
love can keep4 ,we delight to remember  
him in that pleasant summer home at     

,newport1 which he made so fully in     
reality as in name the ,morning-side1   
that we never thought of him as old1 and
 to believe that the morning glow which 
he so often watched spreading above the 
eastern ocean was the promise of the    
fuller day on which he has entered4     
,,viii4  ,,jean-,,baptiste-,,andre      
,,dumas4,k   ,jean-,baptiste-,andre     
,dumas was born at ,alais1 in the south 
of ,france1 ,july #ad1 #ahjj4 ,his      
father belonged to an ancient family1   
was a man of culture1 and held the      
position as clerk to the municipality of
 ,alais4 ,the son was educated at the   
college of his native place1 and appears
 to have been destined by his parents   
for the naval service4 ,but the anarchy 
and bloodshed which attended the        
downfall of the ,first ,empire produced 
such an aversion to a military life that
 his parents abandoned their plan1 and  
apprenticed him to an apothecary of the 
town4 ,he remained in this situation1   
however1 but a short time2 for1 owing to

 the same sad causes1 he had formed an  
earnest desire to leave his home1 and1  
his parents yielding to his wish1 he    
traveled on foot to ,geneva in #ahaf1   
where he had relatives who gave him a   
friendly welcome1 and where he found    
employment in the pharmacy of ,le       
,royer4    ,k ,reprinted from the       
,proceedings of the ,american ,academy  
of       ,arts and ,sciences1 vol4 xix1 
#ahhc-'hd4  ,at that time ,geneva was   
the center of much scientific activity1 
and young ,dumas1 while discharging his 
duties in the pharmacy1 had the         
opportunity of attending lectures on    
botany by ,m4 de ,candolle1 on physics  
by ,m4 ,pictet1 and on chemistry by ,m4 
,gaspard de la ,rive2 and from these    
lectures he acquired an earnest zeal for
 scientific investigation4 ,the         
laboratory of the pharmacy gave him the 
necessary opportunities for             
experimenting1 and an observation which 
he made of the definite proportions of  
water contained in various commercial   

salts1 although yielding no new results1
 gained for him the attention and       
friendship of ,de la ,rive4 ,soon after 
we find the young philosopher attempting
 to deduce the volumes of the atoms in  
solid and liquid bodies by carefully    
determining their specific gravities1   
and thus anticipating a method which    
thirty years later was more fully       
developed by ,hermann ,kopp4  ,about    
this time young ,dumas had the good     
fortune to render an important service  
to one of the most distinguished        
physicians of ,geneva1 whose name is    
associated with the beneficial uses of  
iodine in cases of goitre4 ,it had      
occurred to ,dr4 ,coindet that burned   
sponge1 then generally used as a remedy 
for that disease1 might owe its efficacy
 to the presence of a small amount of   
iodine2 and on referring the question to
 ,dumas1 the young chemist not only     
proved the presence of iodine in the    
sponge1 but also indicated the best     
method of administering what proved to  

be almost a specific remedy4 ,it was in 
connection with this investigation that 
,dumas's name first appears in public4  
,the discovery produced a great         
sensation1 and for many years the       
manufacture of iodine preparations      
brought both wealth and reputation to   
the pharmacy of ,le ,royer4  ,soon      
after1 ,dumas formed an intimacy with   
,dr4 ,j4 ,l4 ,prevost1 then recently    
returned from pursuing his studies in   
,edinburgh and ,dublin1 and was induced 
to undertake a series of physiological  
investigations1 which for a time        
withdrew him from his strictly chemical 
studies4 ,several valuable papers on    
physiological subjects were published by
 ,prevost and ,dumas1 which attracted   
the notice of ,alexander von ,humboldt1 
who on visiting ,geneva1 in #ahbb1      
sought out ,dumas and awakened in him a 
desire to seek a wider field of activity
 than his present position opened to    
him4 ,in consequence he removed to      
,paris in #ahbc1 where the reputation he

 had so deservedly earned at ,geneva won
 for him a cordial reception at what was
 then the chief center of scientific    
study in ,europe4 ,la ,place1           
,berthollet1 ,vauquelin1 ,gay-,lussac1  
,thenard1 ,alexandre ,brongniart1       
,cuvier1 ,geoffroy ,st4 ,hilaire1       
,arago1 ,ampere1 and ,poisson1 all      
manifested their interest in the young  
investigator4 ,dumas was soon appointed 
,repetiteur de ,chimie at the ,ecole    
,polytechnique1 and also ,lecturer at   
the ,athenaeum1 an institution founded  
and maintained by public subscription1  
for the purpose of exciting popular     
interest in literature and science2 and 
from this beginning his advancement to  
the highest position which a man of     
science can occupy in ,france was       
extremely rapid4  ,in #ahbf he married  
,mdlle4 ,herminie ,brongniart1 the      
eldest daughter of ,alexandre           
,brongniart1 the illustrious geologist1 
an alliance which not only brought him  
great happiness1 and at the time greatly

 advanced his social position1 but also 
in after years made his house one of the
 chief resorts of the scientific society
 of ,paris4 ,the many who have shared   
its generous hospitality will appreciate
 how greatly1 for more than half a      
century1 ,madame ,dumas has aided the   
work and extended the influence of her  
noble husband4  ,in #ahbh-'bi ,dumas    
united with ,theodore ,olivier and      
,eugene ,peclet in founding the ,ecole  
,centrale des ,arts et ,manufactures1 an
 institution which met with great       
success1 and in which1 as ,professor of 
,chemistry1 ,dumas rendered most        
efficient service for many years2 and in
 #ahgh had the very good fortune to aid 
in celebrating the fiftieth anniversary 
of his own foundation1 and to see it    
acknowledged as among the most important
 and efficient scientific institutions  
of the world4 ,in #ahcb ,dumas succeeded
 ,gay-,lussac as ,professor at the      
,sorbonne2 in #ahce he succeeded        
,thenard at the ,ecole ,polytechnique2  

and in #ahci he succeeded ,deyeux at the
 ,ecole de ,medecine4 ,thus before the  
age of forty he filled successively1 and
 for some time simultaneously1 all the  
important professorships of chemistry in
 ,paris except one4 ,this exception was 
that of the ,college of ,france1 with   
which he was never permanently          
connected1 although it was there that he
 delivered his famous course on the     
,history of ,chemical ,philosophy1 when 
temporarily supplying the place of      
,thenard4  ,dumas early recognized the  
importance of laboratory instruction in 
chemistry1 for which there were no      
facilities at ,paris when he first came 
to what was then the center of the      
world's science2 and in #ahcb founded a 
laboratory for research at his own      
expense4 ,this laboratory1 first        
established at the ,polytechnic ,school1
 was removed to the ,rue ,cuvier in     
#ahci1 where it remained until broken up
 by the ,revolution of #ahdh4 ,the      
laboratory was small1 and ,dumas would  

receive only a few advanced students1   
and these on terms wholly gratuitous4   
,among these students were ,piria1      
,stas1 ,melsens1 ,leblanc1 ,lalande1 and
 ,lewy1 with whose aid he carried on    
many of his important investigations4   
,by the ,revolution of #ahdh ,dumas's   
activities were for a time diverted into
 political channels2 but under the      
,second ,empire his laboratory was      
re-established at the ,sorbonne1 and in 
#ahfh was removed to the ,ecole         
,centrale4  ,the political episode of   
,dumas's life was the natural result of 
an active mind with wide sympathies1    
which recognizes in the pressing demands
 of society its highest duty4 ,the      
political and social upheaval of #ahdh  
seemed at the time to endanger the      
stability in ,france of everything which
 a cultivated and learned man holds most
 dear2 and ,dumas was not one to        
consider his own preferences when he    
felt he could aid in averting the       
calamities which threatened his country4

 ,immediately after the ,revolution of  
,february1 he accepted a seat in the    
,legislative ,assembly offered him by   
the electors of the ,arrondissement of  
,valenciennes4 ,shortly afterward the   
,president of the ,republic called him  
to fill the office of ,minister of      
,agriculture and ,commerce4 ,during the 
,second ,empire he was elevated to the  
rank of ,senator1 and shortly after his 
entrance into the ,senate he became     
,vice-,president of the ,high ,council  
of ,education4 ,in order to reform the  
abuses into which many of the higher    
educational institutions of ,paris had  
fallen1 be accepted a place in the      
,municipal ,council of ,paris1 over     
which he subsequently presided from     
#ahei to #ahgj4  ,in #ahfh ,dumas was   
appointed ,master of the ,mint of       
,france2 but he retained the office only
 during a short time1 for with the fall 
of the ,second ,empire1 in #ahgj1 his   
political career came to an abrupt      
termination4 ,the ,senate had ceased to 

exist1 and in the stormy days which     
followed1 the ,municipal ,council had   
naturally changed its complexion2 and   
even at the ,mint1 the man who had held 
such a conspicuous position under the   
,imperial government was obliged to     
vacate his place4 ,some years previously
 he had resigned his professorships     
because his official positions were     
incompatible with his relations as      
teacher1 and now1 at the age of seventy1
 he found himself for the first time    
relieved from the daily routine of      
official duties1 and free to devote his 
leisure to the noble work of encouraging
 research1 and thus promoting the       
advancement of science4 ,he had reached 
an age when active investigation was    
almost an impossibility1 but his        
commanding position gave him the        
opportunity of exerting a most powerful 
influence1 and this he used with great  
effect4 ,in early life he had been      
elected1 in #ahcb1 a member of the      
,academy of ,sciences in succession to  

,serullas2 in #ahfh he had succeeded    
,flourens as its ,permanent ,secretary2 
and in #ahge he was elected a member of 
the ,french ,academy as successor to    
,guizot1 a distinction rarely attained  
by a man of science4  ,it was1 however1 
as ,permanent ,secretary of the ,academy
 of ,sciences that ,dumas exerted during
 the last years of his life his greatest
 influence4 ,he was the central figure  
and the ruling spirit of this           
distinguished body4 ,no important       
commission was complete without him1 and
 on all public occasions he was the     
orator of the body1 always graceful1    
always eloquent4 ,in announcing ,dumas's
 death to the ,academy1 ,m4 ,rolland1   
the presiding officer1 said3  ,vous     
savez la part considerable que ,dumas   
prenait a vos travaux et vous avez bien 
souvent admire1 comme moi1 la haute     
intelligence et la tact infini avec     
lesquels il savait imprimer a nos       
discussions les formes moderees et      
courtoises inherentes a sa nature et a  

son caractere4 ,sous ce rapport aussi la
 perte de ,dumas est irreparable et cree
 dans l',academie un vide bien difficile
 a combler4 ,aussi1 longtemps encore    
nous chercherons1 a la place qu'il      
occupait au ,bureau avec tant           
d'autorite1 la figure sympathique et    
veneree de notre bienaime ,secretaire   
perpetuel4  ,and while ,dumas was still 
occupying his conspicuous position in   
the ,academy1 one of the most           
distinguished of his ,german            
contemporaries,l wrote of him3 ,an      
ever-ready interpreter of the researches
 of others1 he always heightens the     
value of what he communicates by adding 
from the rich stores of his own         
experience1 thus often conveying lights 
not noticed even by the authors of those
 researches4    ,l ,a4 ,w4 ,hofmann1 in 
,nature1 ,february #f1 #ahhj1 to whose  
admirable       and extended biography  
the writer is indebted for much of the  
material with which this notice has been
 prepared4  ,when the writer last saw   

,dumas1 in the winter of #ahha-'hb1 the 
great chemist had still all the vivacity
 of youth1 and it was difficult to      
realize his age4 ,he took a lively      
interest in all questions of chemical   
philosophy1 which he discussed with     
great earnestness and warmth4 ,there was
 the same fire and the same exuberance  
of fancy which had enchanted me in his  
lectures thirty years before4 ,at an age
 when most men hold speculation in small
 esteem1 ,i was much struck with his    
criticism of a contemporary1 who1 he    
said1 had no imagination1 although he   
spoke with the highest praise of his    
experimental skill4 ,at that time ,dumas
 showed no signs of impaired strength4  
,but during the following year his      
health began to fail1 and he died on the
 #aath of ,april1 at ,cannes1 where he  
had sought a retreat from the severity  
of the winter climate of ,paris4  ,dumas
 was one of the few men whose greatness 
can not be estimated from a single point
 of view4 ,he was not only eminent as an

 investigator of nature1 but even more  
eminent as a teacher and an             
administrator4 ,beginning the study of  
chemistry at the culmination of the     
epoch of the ,lavoisierian system1 and  
regarding1 as he always did1 the author 
of that system with the greatest        
admiration1 he nevertheless was the     
first to discover the weak point in its 
armor and inflict the wound which led to
 its overthrow4 ,without attempting to  
detail ,dumas's numerous contributions  
to chemical knowledge1 we will here only
 refer to three important               
investigations1 which produced a marked 
influence in the progress of chemical   
science4  ,while still in ,geneva1      
,dumas1 as has been said1 made numerous 
determinations of the densities of      
allied substances1 with a view to       
discovering the relations of what he    
called their molecular or atomic        
volumes2 and it is no wonder to us that 
the problem proved too complex to be    
solved at that time4 ,after his removal 

to ,paris he took up the much simpler   
problem which the relations of the      
molecular volumes of aeriform substances
 present1 and his paper ,on ,some       
,points of the ,atomic ,theory1 which   
was published in the ,annales de ,chimie
 et de ,physique for #ahbf1 had an      
important influence in developing our   
modern chemical philosophy4 ,gay-,lussac
 had previously observed1 not only that 
the relative weights of the several     
factors and products concerned in a     
chemical process bear to each other     
definite proportions1 but also that1    
when the materials are aeriform1 the    
relative volumes preserve an equally    
definite and still simpler ratio4       
,moreover1 on the physical side1        
,avogadro1 and afterward ,ampere1 had   
conceived the theory1 that in the state 
of gas all molecules must have the same 
volume4 ,it was ,dumas who first saw    
that these principles furnished an      
important means of verifying the        
molecular and atomic weights4  ,i am    

engaged1 he writes1 in a series of      
experiments intended to fix the atomic  
weights of a considerable number of     
bodies1 by determining their density in 
the state of gas or vapor4 ,there       
remains in this case but one hypothesis 
to be made1 which is accepted by all    
physicists4 ,it consists in supposing   
that1 in all elastic fluids observed    
under the same conditions1 the molecules
 are placed at equal distances1 i4 e41  
that they are present in them in equal  
numbers4 ,an immediate consequence of   
this mode of looking at the question has
 already been the subject of a learned  
discussion on the part of ,ampere--and  
,avogadro1 as the author subsequently   
adds--to which1 however1 chemists1 with 
the exception perhaps of ,m4            
,gay-,lussac1 appear to have given as   
yet but little attention4 ,it consists  
in the necessity of considering the     
molecules of the simplest gases as      
capable of a further division--a        
division occurring in the moment of     

combination1 and varying with the nature
 of the compound4  ,here1 it is obvious1
 are the very conceptions which form the
 basis of our modern chemical           
philosophy2 and at first we are         
surprised that they did not lead ,dumas 
at once to the full realization of the  
consequences which the doctrine of equal
 molecular volumes involves in the      
interpretation of the constitution of   
chemical compounds1 and to the clear    
distinction between the physically      
smallest particles and the chemically   
smallest particles1 or the molecules and
 the atoms1 as we now call the physical 
and the chemical units4 ,this           
distinction is implied throughout       
,dumas's paper already quoted1 and is   
illustrated by a striking example in the
 introduction to his treatise on        
,chemistry applied to the ,arts1        
published two years later2 but the      
ground was not yet prepared to receive  
the seed1 and more than a quarter of a  
century must pass before the full       

harvest of this fruitful hypothesis     
could be reaped4  ,there were1 however1 
two important incidental results of this
 investigation from which chemical      
science immediately profited4 ,one was a
 simple method of determining with      
accuracy the vapor densities of volatile
 substances which has since been known  
by ,dumas's name4 ,the other was a      
radical change in the formula of the    
silicates4 ,on the authority of         
,berzelius1 who based his opinion       
chiefly on the analogy between the      
silicates and the sulphates1 the formula
 ,si,o#c1 had been accepted as          
representing the constitution of silica4
 ,but from the density of both the      
chloride and the fluoride of silicon    
,dumas concluded that the formula was   
,si,o#b1 a conclusion which is now seen 
to be in complete harmony with the      
scheme of allied compounds4 ,to         
,berzelius1 however1 the new views      
appeared wholly out of harmony with the 
system of chemistry which he had so     

greatly assisted in developing1 and he  
opposed them with the whole weight of   
his powerful influence1 and so far      
succeeded as to prevent their general   
adoption for many years4 ,still1 the new
 mode of looking at the constitution of 
silicic acid slowly but surely gained   
ground1 and it is now so firmly rooted  
in our convictions1 that the younger    
generation of chemists will scarcely    
understand the pertinacity with which   
this innovation was resisted4,m    ,m   
,hofmann1 loc4 cit4  ,but if this       
investigation of gas and vapor densities
 brought a great strain upon the        
dualistic system1 the second of the     
three great investigations of ,dumas1 to
 which we have referred1 led to its     
complete overthrow4 ,the experimental   
results of this investigation would not 
be regarded at the present day as       
remarkable1 and can not be compared     
either in breadth or intricacy with the 
results of numerous investigations of a 
similar character which have since been 

made4 ,the most important of these      
results were the substitution products  
obtained by the action of chlorine gas  
on acetic acid4 ,they were published in 
a series of papers entitled ,sur les    
,types ,chimiques1 and the capital point
 made was that chlorine could be        
substituted in acetic acid for a large  
part of the hydrogen without destroying 
the acid relations of the product2 and  
the inference was1 that the qualities of
 a compound substance depend not simply 
on the nature of the elements of which  
it consists1 but also on the manner or  
type according to which these elements  
are combined4  ,to the chemists of the  
present day these results and inferences
 seem so natural that it is difficult to
 understand the spirit with which they  
were received forty years ago4 ,but it  
must be remembered that at that time the
 conceptions of chemists were wholly    
molded in the dualistic system4 ,it was 
thought that chemical action depended   
upon the antagonism between metals and  

metalloids1 bases and acids1 acid salts 
and basic salts1 and that the qualities 
of the products resulted from the       
blending of such opposite virtues4 ,that
 chlorine should unite with hydrogen was
 natural1 for no two substances could be
 more unlike2 but that chlorine should  
supply the place of hydrogen in a       
chemical compound was a conception which
 the dualists scouted as absurd4 ,even  
,liebig1 the father of organic          
chemistry1 warmly controverted the      
interpretation which ,dumas had given to
 the facts he had discovered4 ,liebig   
himself had successfully investigated   
the chemical relations of a large class 
of organic products4 ,he had1 however1  
worked on the lines of the dualistic    
system1 showing that organic substances 
might be classed with similar inorganic 
substances1 if we assume that certain   
groups of atoms1 which he called        
compound radicals1 might take the place 
of elementary substances4 ,in the       
edition of the organic part of ,turner's

 ,chemistry bearing his name1 organic   
chemistry is defined as the chemistry of
 compound radicals1 and the formulas of 
organic compounds are represented on the
 dualistic system4 ,liebig's conceptions
 were therefore naturally opposed to    
those advanced by ,dumas2 but it is     
pleasant to know that the controversy   
which arose never disturbed the friendly
 relations between these two noble men  
of science1 who could approach the same 
truth from different sides1 and yet have
 faith that each was working for the    
same great end4 ,in his commemorative   
address on ,pelouze1 ,dumas expresses   
toward ,liebig sentiments of            
affectionate regard1 and ,liebig        
dedicates to ,dumas1 with equal warmth1 
the ,german edition of his ,letters on  
,chemistry4  ,by the second             
investigation1 as by the first1 although
 ,dumas gave a most fruitful conception 
to chemistry1 he only took the first    
step in developing it4 ,his conception  
of chemical types was very indefinite1  

and ,laurent wrote of it1 a few years   
later3 ,dumas's theory is too general2  
by its poetic coloring1 it lends itself 
to false interpretations2 it is a       
programme of which we await the         
realization4 ,laurent himself helped    
toward this realization1 and in his     
early death left the work to his        
associate and friend ,gerhardt1 who     
pushed it forward with great zeal1      
classifying chemical compounds according
 to the four types of hydrochloric acid1
 water1 ammonia1 and marsh-gas4         
,hofmann1 ,williamson1 ,wurtz1 and many 
others1 greatly aided in this work by   
realizing many of the possibilities     
which these types suggested2 and thus   
modern ,structural ,chemistry gradually 
grew up1 in which the types of ,dumas   
and ,gerhardt have been in their turn   
superseded by the larger views which the
 doctrine of quantivalence has opened   
out to the scientific imagination4 ,it  
is a singular fact1 however1 that1 while
 the growth began in ,france1 the       

harvest has been chiefly reaped by      
,germans2 and that1 although in its     
inception the movement was strongly     
opposed in ,germany1 its legitimate     
conclusions are now repudiated by the   
most influential school of ,french      
chemists4  ,the third great             
investigation of ,dumas was his revision
 of the atomic weights of many of the   
chemical elements1 and in none of his   
work did he show greater experimental   
skill4 ,his determination of the atomic 
weight of oxygen by the synthesis of    
water1 and of that of carbon by the     
synthesis of carbonic dioxide1 are      
models of quantitative experimental     
work4 ,to this investigation1 as to all 
his other work1 ,dumas was directed by  
his vivid scientific imagination4 ,in   
his teaching1 from the first1 he had    
aimed to exhibit the relations of the   
elementary substances by classing them  
in groups of allied bodies2 and at the  
meeting of the ,british ,association in 
#ahea he had delighted the chemical     

section by the eloquence and force with 
which he exhibited such relations1      
especially triads of elementary         
substances2 such as chlorine1 bromine1  
and iodine2 oxygen1 sulphur1 and        
selenium2 phosphorus1 arsenic1 and      
antimony2 calcium1 barium1 and          
strontium3 in which not only the atomic 
weight1 but also the qualities of the   
middle member of the triad1 were the    
mean of those of the other two members4 
,later1 he came to regard these triads  
as parts of more extended series1 in    
each of which the atomic weights        
increased from the first to the last    
element of the series1 by determinate1  
but not always by equal differences1 the
 values being1 if not exact multiples of
 the hydrogen atom according to the     
hypothesis of ,prout1 at least multiples
 of one half or one quarter of that     
weight4 ,there can be no doubt that     
these speculations were more fanciful   
than sound1 and that ,dumas did not do  
full justice to earlier theories of the 

same kind2 but with him these           
speculations were merely the ornaments1 
not the substance of his work1 and they 
led him to fix more accurately the      
constants of chemistry1 and thus to lay 
a trustworthy foundation upon which the 
superstructure of science could safely  
be built4  ,that exuberance of fancy to 
which we have referred made ,dumas one  
of the most successful of teachers1 and 
one of the most fascinating of          
lecturers4 ,it was the privilege of the 
writer to attend the larger part of two 
of his courses of lectures given in     
,paris1 in the winters of #ahdh and     
#ahea1 and he remembers distinctly the  
impression produced4 ,besides the       
well-arranged material and the carefully
 prepared experiment1 there was an      
elegance and pomp of circumstance which 
added greatly to the effect4 ,the large 
theatre of the ,sorbonne was filled to  
overflowing long before the hour4 ,the  
lecturer always entered at the exact    
moment1 in full evening dress1 and held 

to the end of a two hours' lecture the  
unflagging attention of his audience4   
,the manipulations were entirely left to
 the care of a number of assistants1 who
 brought each experiment to a conclusion
 at the exact moment when the           
illustration was required4 ,an elegance 
of diction1 an appropriateness of       
illustration1 and a beauty of           
exposition1 which could not be excelled1
 were displayed throughout1 and the     
enthusiasm of a ,french audience added  
to the animation of the scene4  ,to the 
writer the lectures of ,dumas were      
brought in contrast to those of         
,faraday4 ,both were perfect of their   
kind1 but very different4 ,faraday's    
method was far more simple and natural1 
and he excelled ,dumas in bringing home 
to young minds abstruse truths by the   
logic of well-arranged consecutive      
experiment4 ,with ,dumas there was no   
attempt to popularize science2 he       
excelled in clearness and elegance of   
exposition4 ,he exhausted the subject   

which he treated1 and was able to throw 
a glow of interest around details which 
by most teachers would have been made   
dry and profitless4  ,two volumes of    
,dumas's lectures have been published2  
one comprises his course on the         
,philosophy of ,chemistry1 delivered at 
the ,college of ,france in #ahcf2 the   
other contains only a single lecture1   
accompanied by notes1 entitled ,the     
,balance of ,organic ,life1 which was   
delivered at the ,medical ,school of    
,paris1 ,august #bj1 #ahda4 ,in both    
these volumes will be found the beauty  
of exposition and the elegance of       
diction of which we have spoken1 and    
they are models of literary style4 ,but 
of course the sympathetic enthusiasm of 
the great man's presence can not be     
reproduced by written words4  ,the      
lecture on ,the ,balance of ,organic    
,life was probably the most remarkable  
of ,dumas's literary efforts4 ,it dealt 
simply with the relations which the     
vegetable sustains to the animal kingdom

 through the atmosphere1 which1 though  
now so familiar1 were then not generally
 understood2 and the late ,dr4 ,jeffries
 ,wyman1 who heard the lecture1 always  
spoke of it with the greatest           
enthusiasm4  ,as might be expected1     
,dumas's oratory found an ample field in
 the ,chamber of ,deputies and in the   
,senate2 and whether setting forth a    
project of recasting the copper coinage 
or a law of drainage1 or ridiculing the 
absurd theories of homoeopathy1 he      
riveted the attention of his colleagues 
as completely as he had entranced the   
students at the ,sorbonne4  ,in the     
early part of his life1 ,dumas was a    
voluminous writer1 and in #ahbh         
published the ,traite de ,chimie        
appliquee aux ,arts1 in eight large     
octavo volumes1 with an atlas of plates 
in quarto4 ,but besides this extended   
treatise1 the two volumes of lectures   
just referred to are his only important 
literary works4 ,he published numerous  
papers in scientific journals1 which1 as

 we have seen1 produced a most marked   
effect on the growth of chemical        
science4 ,but the number of his         
monographs is not large compared with   
those of many of his contemporaries1 and
 his work is to be judged by its        
importance and influence rather than by 
the extent of the field which it covers4
  ,in his capacity of ,president of the 
,municipal ,council at ,paris1 of       
,minister of ,agricultural ,commerce1 of
 ,vice-,president of the ,high ,council 
of ,education1 and of ,perpetual        
,secretary of the ,academy of ,sciences1
 ,dumas had abundant opportunity for the
 exercise of his administrative ability1
 and no one has questioned his great    
powers in this direction2 but in regard 
to his political career we could not    
expect the same unanimity of opinion4   
,that he was a liberal under ,louis     
,philippe1 and a reactionist under      
,louis ,napoleon1 may possibly be       
reconciled with a fixed political faith 
and an unswerving aim for the public    

good2 but his scheme for civilian       
billeting 7by which wealthy people      
having rooms to spare in their houses   
would have been compelled to billet     
artisans employed in public works7 leads
 one to infer that his statesmanship was
 not equal to his science4              
,nevertheless1 there can be no question 
about his large-hearted charity4 ,he    
instituted the ,credit ,foncier1 which  
flourishes in great prosperity to this  
day2 he also founded the ,caisse de     
,retraite pour la ,vieillesse1 and      
several other agricultural charities1   
which1 though less successful1 afford   
great assistance to aged workmen4 ,louis
 ,napoleon used to say in jest that the 
whole of the ,war ,minister's budget    
would not have been enough to realize   
,m4 ,dumas's benevolent schemes2 and    
once1 half-dazzled1 half-amused1 by one 
of the chemist's vast sanitary projects1
 he called him the poet of hygiene4  ,it
 was to be expected that a man working  
with such eminent success in so many    

spheres of activity1 and at one of the  
chief centers of the world's culture1   
should be loaded with medals1 and marks 
of distinction of every kind4 ,it would 
be idle to enumerate the orders of      
knighthood1 or the learned societies1 to
 which he belonged1 for1 so far from    
their honoring him1 he honored them in  
accepting their membership4 ,it is a    
pleasure1 however1 to remember that he  
lived to realize his highest ambitions  
and to enjoy the fruits of his          
well-earned renown4 ,france has added   
his name in the ,pantheon    ,,aux      
,,grands ,,hommes ,,la ,,patrie         
,,reconnaissante4     ,,ix4  ,,the      
,,greek ,,question4,n   ,the question   
whether the college faculty ought to    
continue to insist on a limited study of
 the ancient ,greek language1 as an     
essential prerequisite of receiving the 
,a4 ,b4 degree1 has been under          
consideration at ,cambridge for a long  
time2 and1 since the opinions of those  
with whom ,i naturally sympathize have  

been so greatly misrepresented in the   
desultory discussion which has followed 
,mr4 ,adams's ,phi ,beta ,kappa oration1
 ,i am glad of the opportunity to say a 
few words on the ,greek question4    ,n 
,remarks made at the dinner of the      
,harvard ,club of ,rhode       ,island1 
,newport1 ,august #be1 #ahhc4  ,this    
question is by no means a new one4 ,for 
the last ten years it has been under    
discussion at most1 if not at all1 of   
the great universities of the world2    
and1 among others1 the ,university of   
,berlin1 which stands in the very front 
rank1 has already conceded to what we   
may call the new culture all that can   
reasonably be asked4  ,let me begin by  
asserting that the responsible advocates
 of an expansion of the old academic    
system do not wish in the least degree  
to diminish the study of the ,greek     
language1 the ,greek literature1 or the 
,greek art4 ,on the contrary1 they wish 
to encourage such studies by every      
legitimate means4 ,for myself ,i believe

 that the old classical culture is the  
best culture yet known for the literary 
professions2 and among the literary     
professions ,i include both law and     
divinity4 ,fifty years ago ,i should    
have said that it was the only culture  
worthy of the recognition of a          
university4 ,but we live in the present1
 not in the past1 and a half-century has
 wholly changed the relations of human  
knowledge4 ,regard the change with favor
 or disfavor1 as you please1 the fact   
remains that the natural sciences have  
become the chief factors of our modern  
civilization2 and--which is the         
important point in this connection--they
 have given rise to new professions that
 more and more every year are opening   
occupations to our educated men4 ,the   
professions of the chemist1 of the      
mining engineer1 and of the electrician1
 which have entirely grown up during the
 lifetime of many here present1 are just
 as learned as the older professions1   
and are recognized as such by every     

university4 ,moreover1 the old          
profession of medicine1 which1 when1 as 
formerly1 wholly ruled by authority or  
traditions1 might have been classed with
 the literary professions1 has come to  
rest on a purely scientific basis4  ,in 
a word1 the distinction between the     
literary and the scientific professions 
has become definite and wide1 and can no
 longer be ignored in our systems of    
education4 ,now1 while they would accord
 to their classical associates the right
 to decide what is the best culture for 
a literary calling1 the scientific      
experts claim an equal right to decide  
what is the best culture for a          
scientific calling4 ,ever since the     
revival of ,greek learning in ,europe   
the literary scholars have been working 
out an admirable system of education4   
,in this system most of us have been    
trained4 ,i would pay it all honor1 and 
,i would here bear my testimony to the  
acknowledged facts that in no           
departments of our own university have  

the methods of teaching been so much    
improved during the last few years as in
 the classical4 ,i should resist as     
firmly as my classical colleagues any   
attempt to emasculate the well-tried    
methods of literary culture1 and ,i have
 no sympathy whatever with the opinion  
that the study of the modern languages  
as polite accomplishments can in any    
degree take the place of the critical   
study of the great languages of         
antiquity4 ,to compare ,german          
literature with the ,greek1 or1 what is 
worse1 ,french literature with the      
,latin1 as means of culture1 implies1 as
 it seems to me1 a forgetfulness of the 
true spirit of literary culture4  ,but  
literature and science are very         
different things1 and what is one man's 
meat may be another man's poison1 and   
the scientific teachers claim the right 
to direct the training of their own men4
 ,it is not their aim to educate men to 
clothe thought in beautiful and         
suggestive language1 to weave argument  

into correct and persuasive forms1 or to
 kindle enthusiasm by eloquence4 ,but it
 is their object to prepare men to      
unravel the mysteries of the universe1  
to probe the secrets of disease1 to     
direct the forces of nature1 and to     
develop the resources of this earth4    
,these last aims may be less spiritual1 
lower on your arbitrary intellectual    
scale1 if you please1 than the first2   
but they are none the less legitimate   
aims which society demands of educated  
men3 and all we claim is that the       
astronomers1 the physicists1 the        
chemists1 the biologists1 the           
physicians1 and the engineers1 who have 
shown that they are able to answer these
 demands of society1 should be intrusted
 with the training of those who are to  
follow them in the same work4  ,now1    
such is the artificial condition of our 
schools1 and so completely are they     
ruled by prescription1 that1 when we    
attempt to lay out a proper course of   
training for the scientific professions1

 we are met at the very outset by the   
,greek question4 ,greek is a requisition
 for admission to college1 and the only 
schools in which a scientific training  
can be had do not teach ,greek1 and1    
what is more1 can not be expected to    
teach it4  ,this brings us to the root  
of the whole difficulty with which the  
teachers of natural science have been   
contending1 and which is the cause of   
the present movement4 ,we can not obtain
 any proper scientific training from the
 classical schools1 and the present     
requisitions for admission to college   
practically exclude students prepared at
 any others4 ,at ,cambridge we have     
vainly tried to secure some small       
measure of scientific training in the   
classical schools3 first1 by            
establishing summer courses in practical
 science especially designed for        
training teachers1 and chiefly resorted 
to by such persons2 and1 secondly1 by   
introducing some science requisitions   
into the admission examinations4 ,but   

the attempt has been an utter failure4  
,the science requisitions have been     
simply crammed1 and the result has been 
worse than useless2 because1 instead of 
securing any training in the methods of 
science1 it has in most cases given a   
distaste for the whole subject4 ,true   
science-teaching is so utterly foreign  
to all their methods that the           
requisitions have merely hampered the   
classical schools1 and the sooner they  
are abandoned the better4 ,both the     
methods and the spirit of literary and  
scientific culture are so completely at 
variance that we can not expect them to 
be successfully united in the same      
preparatory school4  ,we look1          
therefore1 to entirely different schools
 for the two kinds of preparation for   
the university which modern society     
demands--schools1 which for the want of 
better distinctive names1 we may call   
classical and scientific schools4 ,in   
the classical school the aim should be1 
as it has always been1 literary culture1

 and the end should be that power of    
clothing thought in words which awakens 
thought4 ,of course1 the results of     
natural science must to a certain extent
 be taught2 for even literary men can   
not afford to be wholly ignorant of the 
great powers that move the world4 ,but  
the natural sciences should be studied  
as useful knowledge1 not as a           
discipline1 and such teaching should not
 be permitted in the least degree to    
interfere with the serious business of  
the place4 ,in the scientific school1 on
 the other hand1 while language must be 
taught1 it should be taught as a means1 
not as an end4 ,the educated man of     
science must command at least ,french   
and ,german--and for the present a      
limited amount of ,latin--as well as his
 mother-tongue1 because science is      
cosmopolitan4 ,but these languages      
should be acquired as tools1 and studied
 no further than they are essential to  
the one great end in view1 that         
knowledge which is the essential        

condition of the power of observing1    
interpreting1 and ruling natural        
phenomena4  ,in such a course as this it
 is obvious that the study of ,greek    
would have no place1 even if there were 
time to devote to it1 and we can not    
alter the appointed span of human life1 
even out of respect to this most honored
 and worthy representative of the       
highest literary culture4 ,of course1 no
 one will question that the scholar who 
can command both the literary and       
scientific culture will be thereby so   
much the stronger and more useful man2  
and certainly let us give every         
opportunity to the double firsts to     
cultivate all their abilities1 and so   
the more efficiently to benefit the     
world4 ,but such powers are rare1 and   
the great body of the scientific        
professions must be made up of men who  
can only do well the special class of   
work in which they have been trained2   
and1 if you make certain formal and     
arbitrary requisitions1 like a small    

amount of ,greek1 obstacles in the way  
of their advancement1 or of that social 
recognition to which they feel          
themselves entitled as educated men1    
those requisitions must necessarily be  
slighted1 and your policy will give rise
 to that cry of fetich of which recently
 we have heard so much4  ,now1 all the  
schools which prepare students for      
,harvard ,college are classical schools4
 ,we do not wish to alter these schools 
in any respect1 unless to make them more
 thorough in their special work4 ,as ,i 
have already said1 the small amount of  
study of natural science which we have  
forced upon them has proved to be a     
wretched failure1 and the sooner this   
hindrance is got out of their way the   
better4 ,we do not wish to alter the    
studies of such schools as the ,boston  
and ,roxbury ,latin ,schools1 the       
,exeter and ,andover ,academies1 the    
,st4 ,paul's and the ,st4 ,mark's       
,schools1 and the other great feeders of
 the college4 ,no--not in the least     

degree6 ,we do not ask for any change   
which in our opinion will diminish the  
number of those coming to the college   
with a classical preparation by a single
 man4 ,we look for our scientific       
recruits to wholly different and        
entirely new sources4 ,for1 although we 
think that there are many students now  
coming to us through the classical      
schools who would run a better chance of
 becoming useful men if they were       
trained from the beginning in a         
different way1 yet such is the social   
prestige of the old classical schools   
and of the old classical culture that1  
whatever new relations might be         
established1 the class of students which
 alone we now have would1 ,i am         
confident1 all continue to come through 
the old channels4  ,this is not a mere  
opinion2 for only a very few men avail  
themselves of the limited option which  
we now permit at the entrance           
examinations--nine1 at least1 out of    
ten1 offering what is called maximum in 

classics4  ,we look1 then1 for no change
 in the classical schools4 ,our only    
expectation is to affiliate the college 
with a wholly different class of        
schools1 which will send us a wholly    
different class of students1 with wholly
 different aims1 and trained according  
to a wholly different method4 ,at the   
outset we shall look to the best of our 
,new ,england high-schools for a limited
 supply of scientific students1 and hope
 by constant pressure to improve the    
methods of teaching in these schools1 as
 our literary colleagues have within ten
 years vastly improved the methods in   
the classical schools4 ,in time we hope 
to bring about the establishment of     
special academies which will do for     
science-culture what ,exeter and ,st4   
,paul's are doing for classical culture4
 ,we expect to establish a set of       
requisitions just as difficult as the   
classical requisitions--only they will  
be requisitions which have a different  
motive1 a different spirit1 and a       

different aim2 and all we ask is1 that  
they should be regarded as the          
equivalents of the classical            
requisitions so far as college standing 
is concerned4 ,we do not at once expect 
to draw many students through these new 
channels4 ,to improve methods of        
teaching and build up new schools is a  
work of years4 ,but we have the greatest
 confidence that in time we shall thus  
be able to increase very greatly both   
the clientage and the usefulness of the 
university4  ,is this heresy8 ,is this  
revolution8 ,is it not rather the       
scientific method seeking to work out   
the best results in education as        
elsewhere by careful observation and    
cautious experimenting1 unterrified by  
authority or superstition8 ,certainly1  
the philologist must respect our method2
 for of all the conquests of natural    
science none is more remarkable than its
 conquest of the philologists           
themselves4 ,they have adopted the      
scientific methods as well as the       

scientific spirit of investigation2 but1
 while thus widening and classifying    
their knowledge1 they have rendered the 
critical study of language more abstruse
 and more difficult2 and this is the    
chief reason why the time of preparation
 for our college has been so greatly    
extended during the last twenty-five    
years4 ,nominally1 the classical schools
 cover no more ground than formerly1 but
 they cultivate that ground in a vastly 
more thorough and scientific way4       
,these increased requirements of modern 
literary culture suggest another        
consideration1 which we can barely      
mention on this occasion4 ,how long will
 the condition of our new country permit
 its youths to remain in pupilage until 
the age of twenty-three or twenty-four2 
on an average at least three years later
 than in any of the older countries of  
the civilized world8 ,it is all very    
well that every educated man should have
 a certain acquaintance with what have  
been called the humanities4 ,but when   

your system comes to its present        
results1 and demands of the physician1  
the chemist1 and the engineer--whose    
birthright is a certain social status1  
which by accident you temporarily       
control--that he shall pass fully four  
years of the training period of his life
 upon technicalities1 which1 however    
important to a literary man1 are        
worthless in his future calling1 is it  
not plain that your conservatism has    
become an artificial barrier which the  
progress of society must sooner or later
 sweep away8 ,is it not the part of     
wisdom1 however much pain it may cost1  
to sacrifice your traditional           
preferences gracefully when you can     
direct the impending change1 and not to 
wait until the rush of the stream can   
not be controlled8     ,x4  ,,further   
,,remarks ,,on ,,the ,,greek ,,question4
   ,in a former essay ,i endeavored to  
make prominent the essential difference 
between a system of education based on  
scientific culture and the generally    

prevailing system which is based on     
linguistic training4 ,i maintained that 
there is not only a difference of       
subject-matter1 but a difference of     
method1 a difference of spirit1 and a   
difference of aim2 and ,i argued that1  
as the conditions of success under the  
two modes of culture are so unlike1     
there was no danger1 even with the      
amplest freedom1 that the study of the  
physical sciences would supplant or     
seriously interfere with linguistic     
studies4 ,but1 although the drift of my 
argument was plain1 this essay has been 
quoted in order to show that not only   
,greek1 but also all linguistic study1  
would be neglected by the students of   
natural science as soon as it ceased to 
be useful in their profession2 and my   
attempt to point out a basis of         
agreement and co-operation has been made
 the occasion of reiterating the extreme
 doctrine that there can be no liberal  
education not based on the study of     
language4 ,it has been thus assumed that

 scientific culture can not supply such 
a basis1 and in this whole discussion   
the value of the study of ,nature in    
education1 except in so far as this     
study may yield a fund of useful        
knowledge1 has been entirely ignored by 
the advocates of the old system4 ,not   
only has there been no recognition of   
the value of the study of material forms
 and physical phenomena as a mode of    
liberal culture1 but it has been assumed
 throughout that--to use the now        
familiar form of words--no sense for    
conduct and no sense for beauty can be  
acquired except through that special    
type of linguistic training that has so 
long limited elementary education4      
,those who demand a place for           
science-culture certainly have not shown
 the same contemptuous spirit2 and ,i   
venture to suggest that1 if classical   
students were as familiar with the      
methods of natural science as are the   
students of ,nature with philological   
and archaeological study1 they would be 

more charitable to those who differ with
 them on this subject4  ,there are1 of  
course1 two distinct elements in a      
liberal education3 the one the          
acquisition of useful knowledge1 the    
other a training or culture of the      
intellectual faculties4 ,the first      
should be made as broad as possible1 the
 second1 in the present state of        
knowledge1 must unfortunately be greatly
 restricted4 ,while in the passage      
referred to ,i have claimed that1 in a  
system of education based upon science1 
languages should be studied simply as   
tools1 ,mr4 ,matthew ,arnold1 in a      
lecture which he has recently repeatedly
 delivered in this country1 and whose   
constant refrain was the phrases ,i have
 already quoted1 has claimed that1      
although scholars must use the results  
of science as so much literary material1
 they need have nothing to do with its  
methods4 ,in my view1 both positions are
 essentially sound4 ,it has been said   
that the ,greek departments in our      

colleges could do without the scientific
 students much better than scientific   
scholars could do without ,greek1 and   
this remark admits of an evident        
rejoinder4 ,certainly in this age no    
professional man can afford to be       
ignorant of the results of science1 and 
he will constantly be led into error if 
he does not know something of its       
methods4 ,it is perfectly well known    
that very few of the investigators1 who 
have coined the scientific terms derived
 from the ,greek1 so often referred to1 
could read a page of ,herodotus or      
,homer in the original2 and it is       
equally true that ,mr4 ,matthew ,arnold1
 and his compeer1 ,lord ,tennyson1 who  
have shown such large knowledge of the  
results of science1 could not interpret 
the complex relations in which the      
simplest phenomena of ,nature are       
presented to the observer4 ,the greater 
number of the students of ,nature can   
only know the beauties of ,greek        
literature as they are feebly presented 

in translations1 and so the greater     
number of literary students can only    
know of the wonders of ,nature as they  
are inadequately described in popular   
works on science4 ,if it requires years 
of study to enable a student to master  
the meaning of a ,greek sentence1 can we
 expect that in less time a student     
shall be able to unravel the intricacies
 of natural phenomena8 ,it has been said
 that no ,greek scholarship is possible 
for a student who begins the study of   
that language in college4 ,is it        
supposed that scientific scholarship is 
any more possible under such conditions8
  ,in order to teach successfully the   
results of science to college students1 
,i have no desire that they should have 
any preliminary preparation4 ,it has    
been my duty for more than thirty years 
to present the elements of chemistry to 
the youngest class in one of our        
colleges1 and ,i have never had any     
reason to complain of their want of     
interest in the subject4 ,indeed1 ,i    

regard it as a great privilege to be the
 first to point out to enthusiastic     
young men the wonderful vistas which    
modern science has opened to our view4  
,so far as their temporary interest is  
concerned1 ,i should greatly prefer that
 they had never studied the subject     
before coming to college4 ,but even     
enthusiastic interest in popular        
lectures is not scientific culture4 ,a  
few men in every class always have been1
 and will continue to be1 so far        
interested as to make the cultivation of
 science the business of their lives4   
,but such men always labor under the    
disadvantages resulting from a want of  
early training1 and these obstacles     
repel a large number whose natural      
tastes and abilities would otherwise    
have fitted them for a scientific       
calling4 ,the change from one system of 
culture to another1 at the age of       
eighteen1 has all the disadvantages of  
changing a profession late in life4     
,nevertheless1 the college will always  

continue to educate a number of men of  
science in this way4 ,most of these men 
become teachers1 and no one questions   
that their previous linguistic training 
makes them all the more forcible        
expositors of scientific truth4 ,it is  
not for such persons that ,i desire any 
change4 ,i am1 however1 most anxious    
that the university should do its part  
in educating that important class of men
 who are to direct the industries and   
develop the material resources of our   
country4 ,such men can be led to        
appreciate1 and will give time to       
acquire1 an elegant use of language1 but
 they will not devote four or five years
 of their lives to purely linguistic    
training1 and1 if we do not open our    
doors to them1 they will be forced to   
content themselves with such education  
as high-schools1 or1 at best1 technical 
schools1 can offer4 ,but1 while they    
will thus lose the broader knowledge and
 larger scope which a university        
education affords1 the university will  

also lose their sympathy and powerful   
support4 ,such students are now wholly  
repelled from the university1 and1 under
 a more liberal policy1 they would form 
an important and clear addition to our  
numbers1 and--as ,i have said in another
 place--without diminishing by a single 
man the number of those who come to     
college through the classical schools4  
,but there is another class of young men
 with whom a system of education based  
on the study of ,nature would1 as ,i am 
convinced1 be more successful than the  
prevailing system of linguistic culture3
 ,i refer to those who now come to      
college1 some of them through the       
influence of family tradition1 some of  
them through the expectation of social  
advantage1 and a still larger number on 
account of the attractions of           
college-life4 ,many of these are men    
who1 with poor verbal memories1 or want 
of aptitude for recognizing abstract    
relations1 can never become classical   
scholars with any exertion that they can

 be expected to make1 but who can often 
be educated with success through their  
perceptive faculties4 ,these men are the
 dunces of the classical department1    
they add nothing to its strength1 and in
 every classical school are a hindrance 
to the better students2 but some of them
 may become able and useful men1 if     
their interest can be aroused in        
objective realities4 ,of our present    
students1 it is only this class that the
 proposed changes would really affect4  
,those who have tastes and aptitudes for
 linguistic studies would continue to   
come through the old channels1 and of   
such only can classical scholars be     
made4  ,i know very well it is said     
that1 although the classical department 
would be glad to be rid of this         
undesirable element1 yet the change     
could not be made without endangering   
the continuance of the study of ,greek  
in many of our classical schools4 ,but  
can the university be justified in      
continuing a requisition which is       

recognized to be opposed to the best    
interests of an important class of its  
patrons8 ,and certainly it is not       
necessary to protect the study of ,greek
 in this country by any such            
questionable means4 ,i have a great deal
 more faith myself in the value of      
classical scholarship than many of my   
classical colleagues appear to possess4 
,never has one word of disparagement    
been heard from me4 ,i honor true       
classical scholarship as much as ,i     
despise the counterfeit4 ,to maintain   
that the class of classical dunces1 to  
whom ,i have referred1 appreciate the   
beauties of classical literature or     
derive any real advantage from the study
 is1 in my opinion1 to maintain a       
manifest absurdity4 ,fully as much do   
the convicts in a tread-mill enjoy the  
beauties of the legal code under which  
they are compelled to work2 and if1 as  
,chief-,justice ,coleridge has recently 
maintained1 in his speech at ,new       
,haven1 classical scholarship is the    

best preparation for the highest        
distinctions in church and state1       
certainly its continuance does not      
depend on the minimum requisition in    
,greek of this university4,o ,the new   
culture1 although a much younger        
industry1 does not ask for any such     
artificial protection4 ,it only asks for
 an opportunity to show what it can     
accomplish1 and this opportunity it has 
never yet had4 ,even if the largest     
liberty were granted1 those who seek to 
promote a genuine education1 based on   
natural science1 would labor under the  
greatest disadvantages4 ,not only is the
 apparatus required for the new culture 
far more expensive than that of an      
ordinary classical school1 but also more
 personal attention must be given to    
each scholar1 and the ordinary          
labor-saving methods of the class-room  
are wholly inapplicable4 ,in the face of
 such obstacles as these conditions     
present1 the new culture can advance    
only very gradually2 and1 amid the      

rivalry of the old system1 it can only  
succeed by maintaining a very high      
degree of efficiency4 ,the new way will 
certainly not offer any easier mode of  
admission to college than the old2 and  
when it is remembered that the classical
 system has the control of all the      
endowed secondary schools1 the prestige 
of past success1 and the support of the 
most powerful social influence1 it is   
difficult to understand on what the     
opposition to the free development of   
the new education is based4 ,are not    
gentlemen1 who have been talking of a   
revolution in education1 taking counsel 
of their fears rather than of their     
better judgment2 and are they not       
forgetting that the teachers of natural 
science have the same interest in       
upholding the principles of sound       
education as have their classical       
colleagues8 ,certainly there can be no  
question that1 in the future as in the  
past1 they will ever seek to maintain   
the integrity of all the great          

departments of the university           
unimpaired4 ,it has happened before this
 that the judgment1 even of intelligent 
men1 has been warped by their class     
relations or supposed interests2 but as1
 in this country1 the learned class has 
no control of government patronage1 we  
may at least hope that the discussion of
 the ,greek question will never assume  
with us the great bitterness that a     
similar controversy has aroused in      
,germany4    ,o ,this article was       
written and read to the ,faculty of     
,harvard       ,college shortly after   
,lord ,coleridge's visit to the ,united 
,states1 in the autumn of #ahhc4  ,there
 has been a great deal said in this     
discussion about the humanities1 and it 
has been assumed that1 while the        
analysis of the ,greek verb is          
humanizing1 the analysis of the         
phenomena of ,nature is materializing4  
,i can discover nothing humanizing in   
the one or the other1 except through the
 spirit with which they are studied1 and

 ,i know by experience that the spirit  
with which the study of the ,latin and  
,greek grammars is often enforced is    
most demoralizing4 ,those who have been 
born with a facility for language may   
laugh at this statement2 but a boy who  
has been held up to ridicule for the    
want of a good verbal memory1 denied him
 by his ,creator1 long remembers the    
depressing effect produced1 if not the  
malignity aroused1 by the cruelty4 ,many
 are the men1 now eminent in literature 
as well as science1 who have experienced
 the tyranny of a classical school1 so  
graphically described in the            
,autobiography of ,anthony ,trollope2   
and many are the boys who might have    
been highly educated if their perceptive
 faculties had been cultivated1 whose   
career as scholars has been cut short by
 the same tyranny4  ,again1 a great deal
 has been said about specialization at  
an early age1 as if the study of ,nature
 were specializing while the study of   
,latin metres and ,greek accents was    

liberalizing4 ,but how could            
specialization be more strikingly       
illustrated than by a system which      
limits a boy's attention between the    
ages of twelve and twenty to linguistic 
studies to the almost entire exclusion  
of a knowledge of that universe in which
 his life is to be passed1 and which so 
limits his intellectual training that   
his powers of observation are left      
undeveloped1 his judgments in respect to
 material relations unformed1 and even  
his natural conceptions of truth        
distorted8 ,now1 although a special     
culture which has such mischievous      
results as these may be necessary in    
order to command that power over        
language which marks the highest        
literary excellence1 and although a     
university should foster this culture by
 all legitimate means1 yet to enforce it
 upon every boy who aspires to be a     
scholar1 whatever may be his natural    
talents1 is as cruel as the ,chinese    
practice of cramping the feet of women  

in order to conform to a traditional    
ideal of beauty4 ,indeed1 an instructor 
in natural science has very much the    
same difficulty in training classical   
scholars to observe that a              
dancing-master would have in teaching a 
class of ,chinese girls to waltz4       
,again1 it has been said that while the 
opportunities for scientific culture in 
college are ample1 no one will oppose   
such a modification of the requisitions 
for admission as the conditions of this 
culture demand1 provided only we label  
the product of such culture with a      
descriptive name4 ,call the product of  
your scientific culture ,bachelors of   
,science1 we have been told1 and you may
 arrange the requisites of admission to 
your own courses as you choose4 ,i am   
forced to say that this argument1       
however specious1 is neither ingenuous  
nor charitable4 ,if you will label the  
product of a purely linguistic culture  
with an equally descriptive name2 if1   
following the ,french usage1 you will   

call such graduates ,bachelors of       
,letters1 we shall not object to the    
term ,bachelors of ,science2 or1 without
 making so great an innovation1 ,i1 for 
one1 should have no objection to a      
distinction between ,bachelors of ,arts 
in ,letters and ,bachelors of ,arts in  
,science4 ,but it is perfectly well     
understood that in this community the   
degree of ,bachelor of ,arts is for most
 men the one essential condition of     
admission to the noble fraternity of    
scholars1 to what has been called the   
,guild of the ,learned4 ,to refuse this 
degree to a certain class of our        
graduates is to exclude them from such  
associations and from the privileges    
which they afford2 and this is just what
 is intended4 ,hence ,i say that the    
argument is not ingenuous1 and it is not
 charitable because it implies that a   
class of men who profess to love the    
truth as their lives are seeking to     
appear under false colors4 ,to cite     
examples from my own profession only1 ,i

 have always maintained that such men as
 ,davy1 ,dalton1 and ,faraday were as   
truly learned1 as highly cultivated1 and
 as capable of expressing their thoughts
 in appropriate language1 as the most   
eminent of their literary compeers1 and 
,i shall continue to maintain this      
proposition before our ,american        
community1 and ,i have no question that 
sooner or later my claim will be        
allowed1 and the doors of the ,guild of 
the ,learned will be opened to all      
scholars who have acquired by           
cultivation the same power which these  
great men held in such a pre-eminent    
degree by gift of ,nature4  ,lastly1 ,i 
am persuaded that in a large body       
politic like this it is unwise1 and in  
the long run futile1 to attempt to      
protect any special form of culture at  
the expense of another4 ,if one member  
suffers1 all the members suffer with it2
 and what is for the interest of the    
whole is in the long run always for the 
interest of every part4 ,i would welcome

 every form of culture which has        
vindicated its efficiency and its value1
 and in so doing ,i feel that ,i should 
best promote the interests of the       
special department which ,i have in     
charge4     ,,xi4  ,,scientific         
,,culture2 ,,its ,,spirit1 ,,its ,,aim1 
,,and ,,its ,,methods4,p   ,i assume    
that most of those whom ,i address are  
teachers1 and that you have been drawn  
here by a desire to be instructed in the
 best methods of teaching physical      
science4 ,it has therefore seemed to me 
that ,i might render a real service1 in 
this introductory address1 by giving the
 results of my own experience and       
reflection on this subject2 and my      
thoughts have been recently especially  
directed to this topic by the discussion
 in regard to the requisites for        
admission1 which during the past year   
have actively engaged the attention of  
the faculty of this college4    ,p ,an  
address delivered at the opening of the 
,summer ,school of       ,chemistry at  

,harvard ,college1 ,july #g1 #ahhd4  ,at
 the very outset of this discussion we  
must be careful to make a clear         
distinction between instruction and     
education--between the acquisition of   
knowledge and the cultivation of the    
faculties of the mind4 ,our knowledge   
should be as broad as possible1 but1 in 
the short space of human life1 it is    
not1 as a rule1 practicable to          
cultivate1 for effective usefulness1 the
 intellectual powers in more than one   
direction4  ,let me illustrate what ,i  
mean from that department of knowledge  
which is at once the most fundamental   
and the most essential4 ,i refer to the 
study of language4 ,no person can be    
regarded as thoroughly educated who has 
not the power of speaking and writing   
his mother-tongue accurately1 elegantly1
 and forcibly2 and scholars of the      
present day must also command1 to a     
considerable extent1 both the ,french   
and the ,german languages4 ,these three 
languages1 at least1 are the necessary  

tools of the ,american scholar1 whatever
 may be the special field of his        
scholarship1 and his end is gained if he
 has acquired thorough command of these 
tools4 ,but if he goes further1 and     
studies the philology of these          
languages1 their structure1 their       
derivation1 their literature1 the study 
may occupy a lifetime1 and be made the  
basis of severe intellectual training4  
,more frequently1 and as most scholars  
think more effectually1 such linguistic 
training is obtained by the study of the
 ancient languages1 especially the      
,latin and the ,greek1 and no one       
questions the value and efficiency of   
this form of mental discipline4 ,but    
obviously such a preparation is not     
necessary for the use of the modern     
languages as tools1 or in order to      
acquire a knowledge of ancient history1 
of the modes of ancient life1 or the    
results of ancient thought4 ,in recent  
discussions a great deal has been said  
about the value of classical learning1  

and it has been argued that no man could
 be regarded as thoroughly educated who 
had never heard of ,homer or ,virgil1 of
 ,marathon or ,cannae1 of the ,acropolis
 of ,athens or the ,forum of ,rome4     
,certainly not4 ,but all this knowledge 
can be acquired without spending six    
years in learning to read the ,latin and
 ,greek authors in the original1 or in  
writing ,latin hexameters or ,greek     
iambics4 ,the discipline acquired by    
this long study is undoubtedly of the   
highest value1 but its value depends    
upon the intellectual training which is 
the essential result1 and not upon the  
knowledge of ancient life and thought1  
which is merely an incident4  ,now1 this
 same distinction1 which ,i have        
endeavored to illustrate on familiar    
ground1 must not be forgotten in        
considering the relations of physical   
science to education4 ,physical science 
may also be studied from two wholly     
different points of view3 ,first1 to    
acquire a knowledge of facts and        

principles1 which are among the most    
important factors of modern life2       
secondly1 as a means of developing and  
training some of the most important     
intellectual faculties of the mind--for 
example1 the powers of observation1 of  
conception1 and of inductive reasoning4 
,the experimental sciences must often be
 studied chiefly from the first point of
 view4 ,if no man can be regarded as    
thoroughly educated who is ignorant of  
the outlines of ,roman and ,greek       
history3 one who knows nothing of the   
principles of the steam-engine1 or of   
the electric telegraph1 is certainly    
equally deficient4 ,i do not question   
that in our high-schools the physical   
sciences must be taught1 for the most   
part1 as funds of useful knowledge1 and 
in regard to such teaching ,i have only 
a few remarks to make4 ,assuming that   
information is the end to be attained1  
the best method of securing the desired 
result is to present the facts in such a
 way as will interest the scholar1 and  

thus secure the retention of these facts
 by his memory4 ,i think it a very      
serious mistake to attempt to teach such
 subjects by memoriter recitations from 
a text-book1 however well prepared4     
,this method at once makes the subject a
 task2 and1 if in addition the          
preparation for an examination is the   
great end in view1 it is wonderful how  
small is the residuum after the work is 
done4 ,such subjects can always be made 
intensely interesting if presented by   
lectures1 with the requisite            
illustrations1 and ,i do not believe    
that the cramming process required to   
pass an examination adds much to the    
knowledge previously gained4 ,many      
teachers1 finding that the parrot-like  
learning of a text-book is unprofitable1
 attempt to make the exercise more      
valuable by means of problems--usually  
simple arithmetical problems--depending 
upon principles of physics or chemistry4
 ,and there can be no doubt that such   
problems do serve to enforce the        

principles they illustrate2 but ,i am   
afraid they also more frequently1 by    
disgusting the student1 stand in the way
 of the acquisition of the desired      
knowledge4  ,it must not be forgotten1  
in studying the results of science1 that
 the facts are never fully learned      
unless the learner is made to understand
 the evidence on which the facts rest4  
,the child who reads in his physical    
geography that the world revolves on its
 axis1 learns what to him is a mere form
 of words1 until he connects this       
astronomical fact with his own          
observation that the sun rises in the   
east and sets in the west2 and so the   
scholar who reads that water is composed
 of oxygen and hydrogen has acquired no 
real knowledge until he has seen the    
evidence on which this fundamental      
conclusion rests4 ,let1 then1 the       
sciences be taught as they have been in 
schools1 as important parts of useful   
knowledge1 but let them so be taught as 
to engage the interest of the scholar1  

and to direct his attention to the      
phenomena of ,nature4  ,all this1       
however1 is not scientific culture1 in  
the sense in which ,i have constantly   
used the term1 and does not afford any  
special training for the intellectual   
faculties4 ,for myself1 ,i do not desire
 any study of natural history1          
chemistry1 or physics from this point of
 view as a preparation for college2     
simply because1 with the large apparatus
 of the university1 all these subjects  
can be presented more effectively1 and  
be made more interesting1 than is       
possible in the schools4 ,what ,i desire
 to see accomplished by our schools is a
 training in physical science1          
comparable in extent and efficiency with
 that which they now accomplish in the  
ancient languages4 ,and this brings me  
to another topic1 namely1 scientific    
culture as a system of mental training4 
,before attempting to state in what     
scientific culture consists1 we shall do
 well1 even at the expense of some      

repetition1 to show that what often     
passes for scientific culture is far    
different from the system of education  
which we have so constantly advocated4  
,the acquisition of scientific          
knowledge1 however extensive1 does not  
in itself constitute scientific culture1
 nor is the power of reproducing such   
knowledge1 at a competitive examination1
 any test of real scientific power4     
,nevertheless1 the examination papers   
which have been published by the        
universities of ,england and of this    
country show that this is the sole test 
of scientific scholarship on which most 
of these universities rely1 in awarding 
their highest honors to students in     
physical science4 ,the power of so      
mastering a subject as to be able to    
reproduce any portion of it with        
accuracy1 completeness1 and elegance1 at
 a written examination1 is the normal   
result of literary1 not of scientific1  
culture1 and the power is of the same   
order1 whether the subject-matter be    

philology1 literature1 art1 or science4 
,indeed1 scientific are1 as a rule1 much
 less adapted than literary subjects to 
the cultivation of this power4          
,moreover1 it is also true that         
scholars1 having attained to a very high
 degree of scholarship1 may not possess 
this power of stating clearly and       
concisely the knowledge they actually   
possess4 ,we have all of us known       
eminent men1 possessing in a very high  
degree the power of investigating       
,nature1 who have been wholly unable to 
state clearly the knowledge they have   
themselves discovered4 ,great harm has  
been done to the cause of scientific    
culture by attempting to adapt the      
well-tried methods of literary          
scholarship to scientific subjects3 for1
 as ,i have said in another place1      
competitive examinations are no test of 
real attainment in physical science4    
,let me not be understood as disparaging
 the retentive memory and power of      
concentration which enable the student  

to reproduce acquired information with  
accuracy1 rapidity1 and elegance4 ,this 
is a power of the very highest order1   
and is the result of the cultivation to 
a high degree of many of the noblest    
faculties of the mill4 ,and ,i wish to  
enforce is1 that success in such        
examinations is no indication of        
scientific culture1 properly so called4 
,what1 then1 are the tests of true      
scientific scholarship8 ,the answer can 
be made perfectly plain and             
intelligible4 ,the real test is the     
power to study and interpret natural    
phenomena4 ,as in classical scholarship 
the true test of attainment is the power
 to interpret the delicate shades of    
meaning expressed by the classical      
authors1 so in science the true test is 
the power to read and interpret ,nature2
 and this last power1 like the other1   
can as a rule only be acquired by       
careful and systematic training4 ,as    
some men have a remarkable facility for 
acquiring languages1 so also there are  

men who seem to be born investigators of
 ,nature2 but by most men such powers   
can only be acquired through a careful  
training and exercise of the faculties  
of the mind1 on which success depends4  
,no man would be regarded as a classical
 scholar1 however broad and extended his
 knowledge1 if that knowledge had been  
acquired solely by reading ,english     
translations of the classical authors1  
however excellent4 ,so1 no man can be   
regarded as a scientific scholar whose  
knowledge of ,nature has been solely    
derived from books4 ,in either case the 
real scholar must have been to the      
fountain-head and drawn his knowledge   
from the original sources4 ,in order1   
then1 to discover how scientific culture
 must be gained1 we must consider the   
conditions on which the successful study
 and interpretation of ,nature depend4  
,of the powers of the mind called into  
exercise in the investigation of        
,nature1 the most obvious and           
fundamental is the power of observation4

 ,by power of observation is not meant  
simply the ability to see1 to hear1 to  
taste1 or to smell with delicacy1 but   
the power of so concentrating the       
attention on what we observe as to form 
a definite and lasting impression on the
 mind4 ,there are undoubtedly great     
differences among men in the acuteness  
of their sensations1 but successful     
observation depends far less upon the   
acuteness of the senses than on the     
faculty of the mind which clearly       
distinguishes and remembers what is seen
 and heard4 ,we say of a man that he    
walks through the world with his eyes   
shut1 meaning that1 although the objects
 around him produce their normal        
impression on the retina of his eye1 he 
pays no attention to what he sees4 ,the 
power of the naturalist to distinguish  
slight differences of form or feature in
 natural objects is simply the result of
 a habit1 acquired through long         
experience1 of paying attention to what 
he sees1 and the want of this power in  

students who have been trained solely by
 literary studies is most marked4  ,an  
assistant1 who was at the time          
conducting a class in mineralogy1 once  
said to me3 ,what am ,i to do8 ,one of  
my class can not see the difference     
between this piece of blende and this   
piece of quartz 7showing me two         
specimens which bore a certain          
superficial resemblance in color and    
general aspect74 ,my answer was1 ,let   
him look until he can see the           
difference4 ,and1 after a while1 he did 
see the difference4 ,the difficulty was 
not lack of vision1 but want of         
attention4  ,the power of observation1  
then1 is simply the power of fixing the 
attention upon our sensations1 and this 
power of fixing the attention is the one
 essential condition of scholarship in  
all departments of learning4 ,it is a   
power which ought to be cultivated at an
 early age1 and in a system of          
scientific culture the sciences of      
mineralogy and botany afford the best   

field for its culture1 and ,i should    
therefore place them among the earliest 
studies of a scientific course4         
,minerals and plants may be profitably  
studied in the youngest classes of our  
secondary schools1 but they should be   
studied solely from specimens1 which the
 scholar should examine until he can    
distinguish all the characteristics of  
form1 feature1 or structure4 ,i am told 
that in many of our secondary schools   
both mineralogy and botany are studied  
with great success and interest in the  
manner ,i have indicated4 ,but a mistake
 is frequently made in attempting to do 
too much4 ,with mineralogy or botany as 
classificatory sciences1 our secondary  
schools should have nothing to do4 ,the 
discrimination between many1 even of the
 commonest1 species of minerals or      
plants depends upon delicate            
distinctions which are quite beyond the 
grasp of young minds1 and the study of  
botany frequently loses all its value1  
through the ambition of the teacher to  

embrace so much of systematic botany as 
will enable scholars to analyze plants4 
,if a child1 twelve or fourteen years of
 age1 is made to observe the            
characteristic qualities of a few common
 minerals so as to enable it to         
recognize them in the rocks1 and is     
likewise led to examine the structure of
 a few familiar flowers1 not only will a
 new power have been acquired1 but a new
 interest will have been added to life4 
,of course1 the faculty of observation  
thus early exercised in childhood only  
attains the highest degree of           
development after long experience and   
continued practice4 ,the acuteness which
 practice gives is frequently very      
remarkable1 and rude men often surprise 
us by the extent to which their power of
 observation has been cultivated in     
certain special directions4 ,the sailor 
who recognizes the outlines of to him a 
well-known coast1 where the ordinary    
traveler sees nothing but a bank of     
clouds1 or the miner who recognizes in  

the rock indications of valuable ores1  
are illustrations which may give a      
clearer conception of the nature of the 
power we have been attempting to        
describe4  ,naturally following the     
power of observation in the order of    
education is the power of conception    
with the cognate power of abstraction2  
that is1 the power of forming in the    
mind distinct and accurate images of    
objects1 and relations1 which have been 
previously apprehended either by direct 
observation1 or through description2 and
 also the power of confining the        
attention to certain features which     
these images may present to the         
exclusion of all others4 ,this is a     
power which depends very greatly on the 
imagination and is capable of being     
cultivated to a very high degree4 ,there
 is no study which is so well suited to 
the training both of the powers of      
conception and of abstraction as the    
study of geometry4  ,to this end the    
study of geometry should be begun at an 

early period in school-life1 and it     
should be studied at first not as a     
series of propositions logically        
connected1 but as a description of the  
properties and relations of lines1      
surfaces1 and solids--what has sometimes
 been called the science of form4 ,a    
text-book prepared on this idea by ,mr4 
,g4 ,a4 ,hill forms an admirable        
introduction to the study4  ,i esteem   
very highly the system of geometry of   
,euclid1 either in its original form or 
as it has been modified by modern       
writers1 as a means of developing the   
logical faculty4 ,the completeness of   
the proof of the successive propositions
 and their mutual dependence by means of
 which1 as on a series of steps1 we     
mount from simple axiomatic truths to   
the most complex relations1 furnish an  
admirable discipline for the reasoning  
power2 but too often the whole value of 
this discipline is lost by the failure  
of the pupil to form a clear conception 
of the very relations about which he is 

reasoning1 and the study becomes an     
exercise of the memory and nothing more4
 ,often have ,i seen a conscientious and
 faithful student draw an excellent     
figure1 and write out an accurate       
demonstration1 without noticing that the
 two were not mated2 and in a recent    
meeting of teachers of our best         
secondary schools it was gravely        
asserted that solid geometry is the most
 difficult study with which the teachers
 had to deal4 ,in solid geometry1       
however1 the reasoning is no more       
difficult than in plane geometry1 but   
the conceptions are far more complex1   
and1 if the teacher insisted that the   
pupil should not take a single step     
until his conceptions were perfectly    
clear1 all the difficulties would       
disappear4 ,of this ,i am fully         
persuaded1 for ,i have had to encounter 
the same difficulties over and over     
again in teaching crystallography4 ,in  
beginning the study of geometry1 of     
course the power of conception should be

 helped in every possible way4 ,let your
 pupil find out by actual measurement   
that the sum of the angles of a triangle
 is equal to two right angles1 and he   
will easily discover the proof of the   
proposition himself4 ,so1 also1 if he   
actually divides with his knife a       
triangular prism made from a potato or  
an apple into three triangular pyramids1
 he will find no difficulty in following
 the reasoning on which the measurement 
of the solid contents of a sphere       
depends4 ,let me assure teachers that   
the study of geometry1 taught as ,i have
 indicated1 is a most valuable          
introduction to the study of science4   
,but1 as it has been usually taught as a
 preparation for college1 it is almost  
worthless in this respect1 however      
valuable it may be as a logical         
training4  ,i consider practice in      
free-hand drawing from natural objects a
 most valuable means of training both   
the power of observation and the power  
of conception1 besides giving a skill in

 delineation which is of the greatest   
importance to the scientific student4   
,accuracy of drawing requires accuracy  
in observation1 and also the ability to 
seize upon those features of the object 
which are the most prominent and        
characteristic4 ,hence1 in a course of  
scientific training1 the importance of  
practice in drawing can hardly be       
exaggerated1 and it should be made one  
of the most important objects of        
school-work from an early period4  ,to  
the scientific student the powers of    
observation and conception are not      
sought as ends in themselves1 but as    
means of studying ,nature4 ,the precise 
portions of this wide field to which the
 attention of the student shall be      
directed will be determined by many     
circumstances1 and it is not our purpose
 in this address to lay down a plan of  
study4 ,to most students the natural    
history subjects offer the most         
attractive field2 but all1 ,i think1    
will admit that the experimental        

sciences should form a considerable     
portion1 at least1 of the course of all 
scientific students1 whatever specialty 
may subsequently be chosen4 ,that on    
which ,i desire particularly to dwell is
 the spirit in which all these studies  
should be pursued2 and ,i can best      
illustrate what ,i mean by confining my 
remarks to that subject in which ,i am  
most interested1 and in regard to which 
,i have the greatest experience4  ,in a 
course of scientific study1 chemistry   
can not be dissociated from physics1 and
 the two sciences ought to be studied to
 a great extent in connection with each 
other4 ,not only does the philosophy of 
chemistry rest upon physical            
conceptions2 but1 moreover1 chemical    
methods involve physical principles4    
,there is1 however1 a distinction to be 
made2 for1 while some of the departments
 of physics are best studied as a       
preparation for chemistry1 there are    
other subjects which are best deferred  
until the student has some knowledge of 

chemical facts4 ,among the preliminary  
subjects we should mention elementary   
mechanics1 including hydrostatics and   
pneumatics1 and also thermotics2 while  
electricity1 acoustics1 and optics1     
including the large subject of radiant  
energy1 may well be deferred until after
 the study of chemistry4  ,in the study 
both of chemistry and physics there are 
of course two definite objects to be    
kept in view3 ,in the first place1 a    
knowledge of the facts of the science is
 to be acquired2 in the second place1   
the student must learn by experience how
 these facts have been discovered4 ,it  
would be obvious1 from a moment's       
reflection1 that a knowledge of the     
circumstances under which the facts of  
,nature are revealed to the student is  
essential to a complete apprehension of 
the facts themselves4 ,the child who is 
taught that the earth moves in an       
elliptical orbit around the sun in one  
year does not in the least grasp the    
wonderful fact thus stated1 and will not

 come to realize it until he connects   
the statement with the nightly          
procession of the stars in the heavens4 
,and it is just such a connection as    
this which the teacher must seek to     
establish in all scientific teaching4   
,in experimental science such a         
connection is most readily established  
in the mind of the student by means of a
 series of well-arranged experiments1   
which each one repeats for himself at   
the laboratory table4 ,obviously1       
however1 it is impossible1 in a limited 
course of teaching1 to go over the whole
 ground of chemistry and physics in this
 way1 or even over that small portion of
 the ground with which the average      
scientific student can expect to become 
acquainted4 ,nor is this necessary2 for1
 after one has realized the connection  
between phenomena and conclusion in a   
number of instances1 the mind will fully
 comprehend that a similar connection   
exists in other cases1 and will         
understand the limitations with which   

scientific conclusions are to be        
received4  ,hence1 it seems to me that1 
in teaching chemistry or physics1 it is 
best to combine a course of lectures    
which should give a broad view of the   
whole ground with a course of laboratory
 instruction1 which must necessarily be 
more or less restricted4 ,experimental  
lectures are1 ,i am convinced1 much the 
best way of presenting these subjects as
 systematic portions of knowledge4 ,it  
is not necessary that the lectures      
should be formal1 but it is             
all-important that they should be given 
in such a way that the interest of the  
student should be awakened1 and that    
they should be fully illustrated by     
specimens and experiments4 ,what we read
 in a book does not make one half the   
impression that is produced by the words
 of a living teacher1 nor can we realize
 the facts unless we see the phenomena  
described4 ,there is undoubtedly an     
advantage to be gained in subsequently  
reviewing the subject as presented in a 

good text-book1 and such a book may be  
of great use in preparation for an      
examination4 ,but how far examinations  
are of value in enforcing the           
acquisition of knowledge of an          
experimental science is a question on   
which ,i feel a grave doubt4 ,certainly 
their value is very small if1 as is too 
frequently the case1 they lead the      
student to defer all effort to make his 
own the knowledge presented in the      
lectures1 until a final cram4  ,the     
management of lectures1 text-books1 and 
examinations1 will not1 however1 offer  
nearly so great difficulties to the     
teacher as the management of the        
parallel experimental course of         
laboratory teaching4 ,in the last the   
methods are less well tried and demand  
of the teacher a very considerable      
amount of invention and experimental    
skill4 ,to follow mechanically any      
text-book would result in a loss of the 
proper spirit with which the course     
should be conducted and which           

constitutes its chief value4 ,no        
experiments are so good as those which  
have been devised by the teacher1 or1   
still better1 by the pupils themselves4 
,a mere repetition of a process1        
according to a definite description1 has
 no more value than a repetition of a   
form of words in an ordinary school     
recitation4 ,the teacher must make sure 
that the student fully understands what 
he is about1 and comprehends all the    
connections between observations and    
conclusions which it is his aim to      
establish4 ,moreover1 he must constantly
 encourage his students to think and    
work for themselves1 and direct them in 
the methods of inductive reasoning4 ,the
 failure of an experiment may be made   
most instructive if the student is led  
to discover the cause of the failure4 ,a
 leak in his apparatus may be turned to 
a similar profit if the student is shown
 how to discover the leak1 by carefully 
eliminating one part after another until
 the weak point is made evident4  ,the  

direction of an experimental laboratory 
is no easy task4 ,the teacher must make 
each man's work his own1 and follow his 
processes of thought as well as his     
experiments with the most careful       
attention4 ,with large classes much time
 can be saved by going through each     
process on the lecture-room table and   
giving the directions to the class as a 
whole2 but this does not supersede the  
personal attention and instruction which
 each student requires at the laboratory
 table4 ,moreover1 in laboratory        
teaching the teacher must rely1 as we   
have said1 on his own resources1 and but
 few aids can be given4 ,there are      
books1 however1 which will help the     
teacher to prepare himself for his work1
 and ,i am happy to say that a book     
entitled ,the ,new ,physics1 prepared by
 my colleague1 ,professor ,trowbridge1  
is now being printed1 which ,i hope will
 greatly promote the laboratory teaching
 of physics4 ,nichols's abridgment of   
,eliot and ,storer's ,manual has long   

served a similar valuable purpose in    
chemistry1 and there are many excellent 
works on ,qualitative ,analysis1 a study
 which is admirably adapted to develop  
the power of inductive reasoning4       
,there is1 however1 a danger with all   
laboratory manuals1 which must be       
sedulously avoided1 and the danger is   
generally greater the more precise the  
descriptions4 ,they are apt to induce   
mechanical habits which are fatal to the
 true spirit of laboratory teaching4    
,not long ago ,i asked a student1 who   
was working in our elementary           
laboratory1 what he was doing4 ,he      
answered that he was doing ,no4 #bd1 and
 immediately went to find his book to   
see what ,no4 #bd was4 ,i fear that a   
great deal of laboratory work is done in
 a way which this anecdote illustrates1 
and1 if so1 it is a mere waste of time4 
,when teaching qualitative analysis it  
was always with me a constant struggle  
to prevent just such a result1 and many 
of the excellent tables which have been 

prepared to facilitate analysis simply  
encourage the evil practice4 ,it is an  
error to which college students1 with   
their exclusively literary preparation1 
are especially liable1 and ,i have no   
question that the proper conduct of our 
laboratories would be made much easier  
if the students came with a previous    
scientific training4  ,thus far ,i have 
dealt solely with generalities1 and my  
object has been not so much to give     
definite directions as to make          
suggestions which might lead to better  
systems of teaching4 ,the details of    
these systems may vary widely1 and yet  
all may lead to the desired result if   
only the true spirit of scientific      
teaching is preserved1 and a teacher's  
own system is generally the best system 
for him4 ,this leads me to explain my   
own system of teaching chemistry--which 
presents some novelties that may be of  
interest1 and1 although it has been     
worked out in detail in the revised     
edition of the ,new ,chemistry1 just    

published1 still a few words of         
explanation may be of value at this time
 in setting forth its salient points4   
,chemistry has been usually defined as  
the science which treats of the         
composition of bodies1 and in most      
text-books the aim has been to develop  
the scheme of the chemical elements1 and
 to show that1 by combining these       
elements1 all natural and artificial    
substances may be prepared4 ,in the     
larger text-books1 which aim to cover   
the whole ground and to describe all    
known substances1 such a method is both 
natural and necessary4 ,but1 as an      
educational system1 this mode of        
presenting the subject is1 as a rule1   
profitless and uninteresting4 ,the      
student becomes lost amid details which 
he can only very imperfectly grasp1 and 
the great principles of the science1 as 
well as their relations to cognate      
departments of knowledge1 are lost sight
 of4 ,moreover1 the system is           
unphilosophical1 because it presents the

 conclusions of chemistry before the    
observations on which they are based4   
,any one who has attempted to teach     
chemistry from the ordinary elementary  
text-books must have experienced the    
truth of what ,i have said4  ,a student 
learns a lesson about sodium and the    
various salts of this metal1 and1 after 
glibly reciting the words of the        
text-book1 how much more does he know of
 the real relations of these bodies than
 he did before8 ,thus3 ,chloride of     
sodium1 symbol ,na,cl4 ,crystallizes in 
cubes4 ,soluble in water4 ,solubility   
only slightly increased by heat4        
,generally obtained by evaporation of   
sea-water in pans4 ,also found in beds  
in certain geological basins1 from which
 it is extracted by mining4 ,when acted 
upon by sulphuric acid1 hydrochloric    
acid is evolved and sodic sulphate is   
formed1 according to the following      
reaction1 and so on4 ,i have known a    
student to recite all this and a great  
deal more1 without ever dreaming that he

 had been eating chloride of sodium on  
his food1 three times a day at least1   
since he was born4  ,now1 the rational  
system of teaching chemistry is first to
 present to the scholar's mind the      
phenomena of ,nature with which the     
science deals4 ,lead him to observe     
these phenomena for himself2 then show  
him how the conclusions which together  
constitute that system of knowledge we  
call chemistry have been deduced from   
these fundamental facts4 ,my plan is to 
develop this system in the lecture-room 
in as much detail as the time allotted  
will permit2 to illustrate all the      
points by experiment1 and in addition to
 explain more in detail carefully       
selected fundamental experiments1 which 
the student subsequently repeats in the 
laboratory himself4 ,thus ,i make the   
lecture-room instruction and the        
laboratory demonstration go hand in hand
 as complementary parts of a single     
course of teaching4  ,i begin by        
directing the student to observe for    

himself the properties of bodies by     
which substances are distinguished4 ,i  
place in his hands a bit of             
roll-brimstone4 ,he first notices the   
color1 the hardness1 the brittleness1   
and the electrical excitability of this 
material4 ,he next determines its       
density1 its melting-point1 its point of
 ignition1 and1 if practicable1 its     
boiling-point4 ,then he treats the      
brimstone with various solvents1 and    
finds that1 while insoluble in water or 
alcohol1 it dissolves readily in        
sulphide of carbon4 ,afterward he       
evaporates the solution thus made1 and  
obtains definite crystals1 whose forms  
he studies1 and compares with the forms 
of the crystals of the same material    
which he also makes by fusion4 ,lastly1 
he observes the remarkable change which 
follows when fused brimstone is heated  
above its melting-point1 and also the   
peculiar plastic condition which the    
material assumes when the thickened mass
 is poured into water4 ,he will thus be 

led to see that the same material may   
assume different states1 and gain a     
clear conception of the substance we    
call sulphur4 ,after this ,i give the   
student pieces of two metals which      
externally resemble each other1 like    
lead and tin1 in order that1 after      
making another series of observations   
and experiments1 he may come to         
understand on what comparatively slight 
differences of properties the           
distinction between substances is       
frequently based4 ,a comparison is next 
made of the properties of two           
closely-allied liquids1 like methylic   
and ethylic alcohol2 and by this time   
the student attains sufficient skill in 
experimenting to make a comparison      
between two aeriform substances1 like   
oxygen gas and carbonic dioxide4  ,after
 more or less of such preliminary work1 
we are prepared to take up the          
subject-matter of chemistry4 ,in the    
broad fields of ,nature what portion    
does this science cover8 ,natural       

phenomena may obviously be divided into 
two great classes3 ,first1 those changes
 which do not involve a transformation  
of substance2 and1 secondly1 those      
changes whose very essence consists in  
the change of one or more substances    
into other substances having distinctive
 properties4 ,the science of physics    
deals with the phenomena of the first   
class2 the science of chemistry with    
those of the last4 ,any phenomenon of   
,nature which involves a change of      
substance is a chemical change1 and in  
every chemical change one or more       
substances1 called the factors1 are     
converted into another substance or into
 other substances called the products4  
,the first point to be made in teaching 
chemistry is1 that a student should     
realize this statement1 and a number of 
experiments should be shown in the      
lecture-room and repeated in the        
laboratory illustrating what is meant by
 a chemical change4  ,here1 of course1  
arises a difficulty in finding examples 

which shall be at once simple and       
conclusive1 for in almost all natural   
phenomena there is a certain            
indefiniteness which obscures the simple
 process4 ,the familiar phenomena of    
combustion are most striking examples of
 this fact1 and men were not able to    
penetrate the mist which obscured them  
until within a hundred years4 ,to find  
chemical processes whose whole course is
 obvious to an unpracticed observer1 we 
are obliged to resort to unfamiliar     
phenomena4  ,a very simple example of a 
chemical process is a mixture of sulphur
 and zinc in atomic proportions1 which1 
when lighted with a match1 is rapidly   
converted into white sulphide of zinc1  
with appearance of flame4 ,another      
example1 a mixture of sulphur and fine  
iron-filings1 which1 when moistened with
 a little water1 rapidly changes into a 
black sulphide of iron4 ,then some      
copper-filings1 which1 when heated on a 
saucer in the open air1 slowly change   
into black oxide of copper4 ,then a bit 

of phosphorus1 burned in dry air under a
 glass bell1 yielding a white oxide4    
,next1 some zinc1 dissolved in diluted  
sulphuric acid1 yielding hydrogen gas   
and sulphate of zinc4 ,then1 a solution 
of chloride of barium added to a        
solution of sulphate of soda1 giving a  
precipitate of sulphate of baryta1 and  
leaving in solution common salt1 which  
can be recovered by evaporating the     
filtrate4  ,in all these examples the   
student should be made to see and handle
 all the factors and all the products of
 each process1 and the experiments      
should be selected so that he may become
 familiar with the different conditions 
under which substances appear1 and with 
various kinds of chemical processes4 ,he
 should also be made clearly to         
distinguish between the essential       
features of the process and the         
different accessories1 which may be more
 or less accidental--such1 for example1 
as the water used in determining the    
combination of iron and sulphur1 or the 

flame which accompanies combustion4     
,after a clear conception has been      
gained of a chemical process1 with its  
definite factors and definite products1 
we are prepared for the next important  
step4 ,every chemical process obeys     
three fundamental laws3    ,the ,law of 
,conservation of ,mass4   ,the ,law of  
,definite ,proportions4   ,the ,law of  
,definite ,volumes4  ,according to the  
first law1 the sum of the weights of the
 products of a chemical process is      
always equal to the sum of the weights  
of the factors4 ,this law must now be   
illustrated by experiments1 and         
approximate quantitative determinations 
should be introduced thus early into the
 course of study4 ,all that is required 
for this purpose is a common pair of    
scales1 capable of weighing two or three
 hundred grammes1 and turning with a    
decigramme4 ,we use in our laboratory   
some platform-scales1 made by the       
,fairbanks ,company1 which are          
inexpensive1 and serve a very useful    

purpose4  ,a very satisfactory          
illustration of the law of conservation 
of mass can be obtained by inserting in 
a glass flask a mixture of              
copper-filings and sulphur in atomic    
proportions4 ,the glass flask is first  
balanced in the scale-pan2 then removed 
and gently heated until the ignition    
which spreads through the mass shows    
that chemical combination has taken     
place4 ,the flask is lastly allowed to  
cool1 and on reweighing is found not to 
have altered in weight4  ,for a second  
experiment1 a bit of phosphorus may1    
with the aid of some simple contrivance1
 be burned inside a tightly-corked glass
 flask1 of sufficient volume to afford  
the requisite supply of oxygen4 ,of     
course1 on reweighing the flask1 after  
the chemical change has taken place1 and
 the bottom of the flask covered with   
the white oxide formed1 there will be no
 change of weight1 and this experiment  
may be made to enforce the truth that1  
in this example of combustion at least1 

the chemical process is attended with no
 loss of material4 ,open now the flask1 
and air will rush in to supply the      
partial vacuum1 proving that in the     
process of combustion a portion of the  
material of the air has united to form  
the white product4  ,make now a third   
experiment as an application of the     
general principle which has been        
illustrated by the previous experiments4
 ,burn some finely divided iron 7iron   
reduced by hydrogen7 on a scale-pan1 and
 show that the process is attended by an
 increase of weight4 ,what does this    
mean8 ,why1 that some material has      
united with the iron to form the new    
product4 ,whence has this material come8
 ,obviously from the air1 for it could  
come from nowhere else4 ,and thus1      
besides illustrating the first of the   
above laws1 this experiment may be made 
to furnish an instructive lesson in     
regard to the relations of the oxygen of
 the atmosphere to chemical processes4  
,the second law declares that in every  

chemical process the weights of the     
several factors and products bear each  
to the others a definite proportion4    
,this law must next be made familiar by 
experimental illustrations4 ,a weighed  
amount of oxide of silver is placed in a
 glass tube connected with a pneumatic  
trough4 ,the tube is gently heated until
 the oxide is decomposed and the oxygen 
gas collected in a glass bottle of      
sufficient size4 ,the metallic silver   
remaining in the tube is now reweighed1 
and the volume of the oxygen gas in the 
bottle measured1 and from the volume of 
the gas its weight is deduced4 ,the     
measurement is easily made by simply    
marking with a gummed label the level at
 which the water stands in the bottle4  
,if1 now1 the bottle is removed from the
 pneumatic trough and the weight of     
water found which fills the bottle to   
the same height1 the weight of the water
 in grammes will give the volume of the 
gas in cubic centimetres1 and1 knowing  
the weight of a cubic centimetre of     

oxygen1 we easily calculate the weight  
of this gas resulting from the chemical 
process4 ,we have now the weights of the
 oxide of silver1 the silver1 and the   
oxygen1 the one factor and the two      
products of the chemical process1 and1  
by comparing the results of different   
students making the same experiment1 the
 constancy of the proportion will be    
made evident to the class4  ,for a      
second illustration of the same law1 the
 solution of zinc in dilute sulphuric   
acid1 yielding sulphate of zinc and     
hydrogen gas1 may be selected1 and the  
weight of the hydrogen1 estimated as in 
the previous example1 shown to sustain a
 definite relation to the weight of the 
zinc dissolved4  ,again1 silver may be  
dissolved in nitric acid1 and the weight
 of the nitrate of silver obtained shown
 to sustain a definite relation to the  
weight of the metal4  ,or1 still        
further1 as an experiment of a wholly   
different class1 a known weight of      
chloride of barium may be dissolved in  

water1 and1 after precipitation with    
sulphuric acid1 the baric sulphate      
collected by filtration and weighed1    
when the definite relation between the  
weight of the precipitate and the weight
 of the chloride of barium will appear4 
,for a last experiment let the student  
neutralize a weighed amount of dilute   
hydrochloric acid with aqua ammonia1    
noting approximately the amount of      
ammonia required4 ,let him now evaporate
 the solution on a water-bath1 and weigh
 the resulting saline product2 taking   
next the same quantity of hydrochloric  
acid as before1 and1 having added twice 
the previous quantity of ammonia1 let   
him obtain and weigh the resulting      
salammoniac as before4 ,a third time let
 him begin with half the quantity of    
hydrochloric acid1 and1 adding as much  
ammonia as in the first case1 again     
repeat the process4 ,it is obvious what 
the result of these experiments must be2
 but without telling the student what he
 is to expect1 it will be a good        

exercise to ask him to draw his own     
inferences from the results4 ,of course1
 he must previously have so far been    
made acquainted with the properties of  
hydrochloric acid and ammonia as to know
 that the excess of either would escape 
when the saline solution is evaporated  
over a water-bath4 ,but with this       
limited knowledge he will be able to    
deduce the law of definite proportions  
from the experimental results thus      
simply obtained4  ,the third of the     
fundamental laws of chemistry stated    
above 7generally known as the law of    
,gay-,lussac7 declares that1 when two or
 more of the factors or products of a   
chemical process are aeriform1 the      
volumes of these gaseous substances bear
 to each other a very simple ratio4     
,here1 again1 numerous experiments may  
be contrived to illustrate the law4     
,water1 when decomposed by electricity1 
yields hydrogen and oxygen gases whose  
volumes bear to each other the ratio of 
two to one4 ,when hydrochloric-acid gas 

is decomposed by sodium amalgam1 the    
volume of the original gas bears to that
 of the residual hydrogen the ratio also
 of two to one4 ,when ammonia is        
decomposed by chlorine1 the volume of   
the resulting nitrogen gas is one third 
of that of the chlorine gas employed4   
,having illustrated these three general 
laws1 attention should be directed to   
the fact that the nature of a chemical  
process and the laws which it obeys are 
results of observation and involve no   
theory whatsoever4 ,on these facts the  
science of chemistry is built4 ,the     
modern system of chemistry1 however1    
assumes what is known as the molecular  
theory1 and by means of this theory     
attempts to explain all these facts and 
show their mutual relations4 ,here the  
distinction between fact and theory must
 be insisted upon1 and also the value of
 theory for classifying facts and       
directing observation4  ,a molecule is  
now defined1 and1 if the student has not
 studied physics sufficiently to become 

acquainted with the outlines of the     
kinetic theory of gases1 this theory    
must be developed sufficiently to give  
the student a knowledge of the three    
great laws of ,mariotte1 of ,charles1   
and of ,avogadro4 ,he must be made to   
understand how molecules are defined by 
the physicist1 and how their relative   
weights may be inferred by a comparison 
of vapor densities4 ,he should then be  
made to compare the relative molecular  
weights1 deduced by physical means1 with
 the definite proportions he has        
observed in chemical processes4 ,he will
 thus himself be led to the conclusion  
that these definite proportions are the 
proportions of the molecular weights1   
and that the constancy of the law arises
 from the fact that in every chemical   
process the action takes place between  
molecules1 and that the products of the 
process are new molecules1 preserving   
always1 of course1 their definite       
relative weights4 ,the student will thus
 be brought to the chemical conception  

of the molecule as the smallest mass of 
any substance in which the qualities    
inhere1 and he will come to regard a    
chemical process as always taking place 
between molecules4  ,thus far nothing   
has been said about the composition of  
matter4 ,a chemical process has been    
defined simply as certain factors       
yielding certain products1 but nothing  
has been determined about the relations 
of these several substances except in so
 far as they are defined by the three   
laws illustrated above4 ,but now it must
 be shown that a study of different     
chemical processes compels us to        
conclude that in some cases two or more 
substances unite to form a compound1    
while in other cases a compound is      
broken up into simpler parts4 ,thus1    
when copper-filings are heated in the   
air1 it is evident that the material of 
the copper has united with that portion 
of the air we call oxygen to form the   
black product we call oxide of copper2  
and again1 when oxide of silver is      

heated1 it is evident that the resulting
 silver and oxygen gas were formerly    
portions of the material of the oxide4  
,so1 when water is decomposed by        
electricity1 the conditions of the      
experiment show that the resulting      
oxygen and hydrogen gases must have come
 from the material of the water1 and    
could have come from nothing else4      
,experiments should now be multiplied   
until the student has a perfectly clear 
idea of the nature of the evidence on   
which our knowledge of the composition  
of bodies depends4 ,the decomposition of
 chlorate of potash by heat1 yielding   
chloride of potassium and oxygen gas2   
the decomposition of nitrate of ammonium
 by heat1 yielding nitrous oxide and    
water2 the decomposition of this        
resulting nitrous oxide1 when the gas is
 passed over heated metallic copper2    
and1 lastly1 the decomposition already  
referred to1 of water by                
electricity--are all striking           
experiments by which the evidence of    

chemical composition may be enforced4   
,the distinction between elementary and 
compound substances having been clearly 
defined by the course of reasoning      
already given in outline1 the next aim  
should be to lead the student to        
comprehend how substances are analyzed  
and their composition expressed in      
percents4 ,the reduction of oxide of    
copper by hydrogen gives readily the    
data for determining the composition of 
water1 which is thus shown to contain in
 one hundred parts #aa4aa per cent of   
hydrogen and #hh4hi per cent of oxygen4 
,another substance whose analysis can be
 very readily made by the student is    
carbonate of magnesia4 ,by igniting pure
 carbonate of magnesia in a crucible    
7not of course the magnesia alba of the 
shops71 the proportions of carbonic acid
 and magnesia can be readily determined4
 ,then1 by burning magnesium ribbon1 and
 weighing the product1 the student      
easily finds the relative weight of     
magnesium and oxygen in the oxide4 ,and1

 lastly1 the proportion of carbon and   
oxygen in carbonic dioxide is easily    
deduced from the burning of a weighed   
amount of carbon4 ,here the result may  
be expressed either in percents of oxide
 or magnesium and carbonic dioxide1 or  
else in percents of the elementary      
substances1 carbon1 magnesium1 and      
oxygen4  ,after making a few analyses   
like these1 the student will be prepared
 to comprehend the actual position of   
the science4 ,all known substances have 
been analyzed1 and the results          
tabulated1 so that it is unnecessary to 
repeat the work except in special cases4
  ,the teacher is now prepared to take a
 very important step in the development 
of the subject4 ,if the molecule is     
simply a small particle of a substance  
in which the qualities of the substance 
inhere1 then it follows1 of course1 that
 the composition of the molecule is the 
same as the composition of the          
substance4 ,the percentage results of   
the analysis of water1 or of carbonate  

of magnesia1 indicate the composition of
 a molecule of water or a molecule of   
carbonate of magnesia4 ,thus1 #aa4aa per
 cent of every molecule of water        
consists of hydrogen1 while #hh4hi per  
cent consists of oxygen4 ,hence it      
follows that1 in a chemical process1 the
 molecules must be divided1 and these   
elementary parts of molecules which     
analysis reveals are the atoms of       
chemistry4 ,moreover1 as we know the    
weights of molecules1 both by physical  
and chemical means1 chemical analysis   
now gives us the weights of the atoms4  
,we have no time to dwell on the details
 of this reasoning1 but the general     
course to be followed will be evident1  
and it must be enforced by numerous     
examples4  ,assuming that the student   
fully comprehends the distinction       
between molecules and atoms--that is1   
between the physically smallest         
particles and the chemically smallest   
particles--he is prepared to master the 
symbolical nomenclature of chemistry1   

with a very few words of explanation4   
,the initial letters of the ,latin names
 are selected to represent the atoms of 
the seventy known elementary substances1
 and these letters stand for the        
definite atomic weights which are       
tabulated in all chemical text-books4   
,the symbols of the atoms are simply    
grouped together to form the symbols of 
the molecules of the various substances2
 the number of atoms of each kind       
entering into the composition of the    
molecule being indicated by a subscript 
numeral4 ,lastly1 in order to represent 
chemical processes1 the symbols of the  
molecules of the factors are written on 
one side and the symbols of the         
molecules of the products are written on
 the other side of an equation1 the     
number of molecules of each substance   
involved being indicated by numerical   
coefficients4  ,the atomic symbols1 as  
we have seen1 stand for definite        
weights4 ,in the same way1 the molecular
 symbols stand for definite weights1    

which are the sums of the weights of the
 atoms of which each consists1 and in   
every chemical equation the weights of  
the molecules represented on one side   
must necessarily equal the weights of   
the molecules represented on the other4 
,the chemical process consists merely in
 the breaking up of certain molecules1  
and the rearrangement of the same       
constituent atoms to form new molecules4
 ,again1 as the molecular symbols       
represent definite weights1 the equation
 also indicates that a definite         
proportion by weight is preserved       
between the several factors and products
 of the process represented4  ,again1   
since every molecular symbol represents 
the same volume when the substance is in
 an aeriform condition1 it follows that 
the relative gas volumes are            
proportional to the number of molecules 
of the aeriform substances involved in  
the reaction4 ,thus it is that these    
chemical equations or reactions are a   
constant declaration of the three great 

fundamental laws of chemistry4  ,in     
order to enforce the above principles1 a
 great number of examples should now be 
given which should be so selected as to 
illustrate familiar and important       
chemical processes1 including the       
all-important phenomena of combustion4  
,in each case1 the student1 having made 
the experiment1 should write the        
equation or reaction which represents   
the process1 and should be made to solve
 a sufficient number of stochio-metrical
 problems1 involving both weights and   
volumes1 to give him a complete mastery 
of the subject4 ,such questions as these
 will test the completeness of his      
knowledge3  ,why is the symbol of water 
,h#b,o8 ,what information does the      
symbol ,,co#b give in regard to         
carbonic-dioxide gas8 ,write the        
reaction of hydrochloric acid on sodic  
carbonate1 and state what information   
the equation gives in regard to the     
process which it represents4  ,of       
course1 such questions may be greatly   

multiplied1 and ,i cite these three only
 to call attention to the features of   
the method of instruction ,i have been  
endeavoring to illustrate4  ,but1       
besides teaching the general principles 
of chemical science1 it is important to 
give the student a more or less extended
 knowledge of chemical facts and        
processes--especially such as play an   
important part in daily life1 or in the 
arts--and such knowledge can readily be 
given in this connection4 ,beyond this  
,i do not deem it desirable to go in an 
elementary course of instruction4 ,the  
way1 however1 is now opened to the most 
advanced fields of the science4 ,a      
comparison of symbols and reactions     
leads at once to the doctrine of        
quantivalence1 and to the results of    
modern structural chemistry which this  
doctrine involves4 ,among these results 
there is of course much that is         
fanciful1 but there is also a very large
 substratum of established truth2 and if
 the student thoroughly comprehends the 

symbolical language of chemistry1 and   
understands the facts it actually       
represents1 he will be able to realize1 
so far as is now possible1 the truths   
which underlie the conventional forms4  
,the study of the structure of molecules
 naturally leads to the study of their  
stability1 and of the conditions which  
determine chemical changes1 and thus    
opens the recently explored field of    
thermo-chemistry4 ,to be able to predict
 the order and results of possible      
conditions of association of materials1 
or of chemical changes under all        
circumstances1 is now the highest aim of
 our science1 and we have already made  
very considerable progress toward this  
end4  ,but ,i have detained you too     
long1 and ,i must refer to the ,new     
,chemistry for a fuller exposition of   
this subject4 ,my object has been gained
 if ,i have been able to make clear to  
you that it is possible to present the  
science of chemistry as a systematic    
body of truths independent of the mass  

of details with which the science is    
usually encumbered1 and make the study a
 most valuable means of training the    
power of inductive reasoning1 and thus  
securing the great end of scientific    
culture4     ,,xii4  ,,noblesse         
,,oblige4   ,in the former essays of    
this volume ,i have earnestly maintained
 that scientific culture1 rightly       
understood1 is a suitable basis for a   
liberal education2 and ,i have          
maintained this thesis without in any   
way attempting to disparage that        
literary culture hitherto so generally  
regarded as the only basis on which the 
liberal arts could be built4 ,while1    
however1 ,i have argued that1 in the    
present condition of the world1 there is
 more than one basis of true            
scholarship1 ,i have fully admitted that
 for far the larger number of scholars1 
including all those whose lives are to  
be occupied with literary pursuits1 the 
old system of education is still the    
best4 ,moreover1 ,i have endeavored to  

point out that scientific culture in no 
way conflicts with literary culture2    
that it has a different spirit1 a       
different method1 and a different aim2  
and ,i have only recommended it as      
suitable to those who are distinctly    
preparing themselves for a scientific   
calling2 but ,i have maintained that for
 such men scientific studies1 rightly   
followed1 may lead to a broad1 a noble1 
and in the truest sense a liberal       
education4  ,i have used the term       
scientific culture rightly understood in
 order to mark a distinction2 because a 
great deal that passes for scientific   
scholarship in the world does not imply 
true scientific culture4 ,in all        
departments of learning1 and not less in
 scientific than in literary studies1   
erudition does not necessarily imply a  
high degree of culture4 ,we all value   
the labors of the lexicographer1 and the
 work may be so done as to task the     
noblest intellectual power2 but there is
 a higher form of literary culture than 

that which dictionary-making usually    
implies4 ,so also in science1 no amount 
of book-learning constitutes what we    
have called scientific culture rightly  
understood4 ,for example1 the ability to
 pass an examination on the facts and   
principles of science is no test        
whatever of the form of culture we are  
advocating4 ,not that we underrate the  
value of such tests1 or of the knowledge
 they imply2 but the ability to master a
 subject as presented in a text-book1   
and to state that knowledge in a concise
 and accurate form1 is the normal result
 of literary1 not of scientific culture4
 ,the power to do something well is     
involved in the very idea of culture1   
and the scholar who can pass a          
successful written examination has      
acquired a power which literary culture 
chiefly gives1 and that this power may  
be applied to scientific as well as     
literary subjects is obvious4 ,here is a
 most important distinction in          
connection with our subject4 ,culture   

implies the acquisition of some power of
 the mind in an eminent degree1 and such
 power is constantly associated with    
erudition1 simply because it leads to   
erudition4 ,but when we see erudition   
without such power1 as we often do in   
every department of scholarship1 we     
perceive at once upon how much lower a  
level it stands4 ,what very different   
things are classical scholarship and    
classical erudition2 and is not the     
power which the great classical scholars
 possess of interpreting the thoughts of
 the classical authors1 and of          
reproducing their life1 the great       
element of difference between the two8  
,so scientific culture implies the      
ability to interpret ,nature1 to observe
 her phenomena1 and to investigate her  
laws4 ,the scholar1 to whom ,nature     
presents merely an orderly succession of
 facts and phenomena1 knows nothing of  
true scientific culture4 ,as there is a 
spirit in the great writers of classical
 antiquity which ennobles the study of  

the forms in which the thoughts of these
 authors were expressed1 so also is     
there a spirit in ,nature without which 
facts and phenomena1 however well       
classified1 create no intellectual      
elevation4 ,the last century of the     
world's history has been marked1 more   
than by anything else1 by the increase  
of our knowledge of ,nature1 and it will
 be known in history as the age of great
 discoveries2 but valuable as the facts 
and principles of science certainly are1
 greatly as they have promoted the      
well-being of mankind1 and important1   
therefore1 as the knowledge of these    
facts and principles must be to man1 yet
 nevertheless ,i should never urge the  
claims of physical science as a basis of
 liberal education if they could be     
defended on no other grounds than these4
 ,it is here as elsewhere the spirit    
which giveth life2 and the power to     
interpret ,nature1 and to commune with  
the intelligence that rules the         
universe1 is the one acquisition which1 

above all others1 gives worth and       
dignity to the form of culture we have  
endeavored to advocate in these essays4 
,those who regard science simply as     
utilitarianism1 and who value scientific
 studies solely because they teach men  
how to build railroads1 to explore      
mines1 to extract the useful metals from
 their ores1 or to increase the yield of
 agriculture1 have an even more         
imperfect conception of what is meant by
 scientific culture than those to whom  
science is merely a valuable erudition4 
,it is true that physics and chemistry  
may be studied as arts rather than as   
sciences1 and we have no desire to      
underrate the importance of such        
technical education2 but the difference 
between the two modes of study is as    
wide as the difference between the      
artisan and the scholar4 ,in asserting  
this we do not forget that the          
occupations of the engineer1 the        
electrician1 and the analytical chemist 
demand a very large amount of knowledge1

 judgment1 and skill1 and are rightly   
regarded as learned professions4 ,but   
let it not be supposed that skill in    
such professions is the end or aim of   
scientific culture2 any more than legal 
skill is the end or aim of literary     
culture4 ,if literary scholars regard   
the study of science solely from this   
point of view1 it is no wonder that they
 think that the tone of scholarship     
would be lowered if it rested solely on 
such a utilitarian basis2 and1 on the   
other hand1 if they could once realize  
the sublimity of ,nature1 as            
,copernicus1 ,newton1 ,faraday1 and     
unnumbered others have realized it1 this
 fear that devotion to science must     
degrade scholarship would disappear4    
,we are well aware that practical men   
frequently regard with undisguised      
contempt the students of theoretical    
science1 and that the greater number of 
persons seeking a scientific education  
must look for employment to the         
practical professions in which this tone

 too often prevails4 ,but1 certainly1 a 
narrow technical spirit prevails quite  
as often in the professions in which    
literary scholars chiefly find          
employment2 and the new scientific      
professions are even more closely       
dependent on the discussion of          
theoretical and abstract principles than
 those which have hitherto been         
exclusively regarded as liberal4 ,it is 
an admitted fact1 as we have shown in   
another place1 that all the great       
advances in practical science1 all the  
great inventions1 which during the last 
century have so wonderfully increased   
the power of man over ,nature1 may be   
traced directly to the results of       
theoretical study4 ,for this reason1 if 
on no higher ground1 we have claimed    
that it is both the interest and the    
duty of the ,state to foster and reward 
scientific investigation4 ,the time is  
not far distant1 if it is not already at
 hand1 when the scientific culture of a 
people will be one of the chief factors 

in determining its position among the   
nations of the world4  ,we can not leave
 this subject without giving prominence 
to another thought1 which has been ever 
present with us while writing these     
pages1 if not hitherto distinctly       
stated4 ,culture1 as we have seen1      
implies power1 and the possession of    
power also involves corresponding       
obligations4 ,among the many blessings  
which ,christianity and its attendant   
civilization have brought to mankind1   
the recognition of this principle is    
most plainly marked4 ,the principle is  
assumed in almost every relation of     
life1 even when not distinctly          
acknowledged2 and happily it can rarely 
now be disregarded without incurring the
 odium of mankind4 ,it leads the        
possessors of great wealth to devote no 
inconsiderable share of their fortunes  
to the public good2 it stigmatizes as   
miserly any neglect of this obligation2 
and the best hope of preserving our     
modern civilization against the         

destructive agencies of socialism is to 
be found in the increasing recognition  
and enforcement of this saving grace4   
,but while this principle is1 to a      
greater or less degree1 acted upon in   
all relations of life1 it is enforced by
 public opinion with special strictness 
upon those who assume to be the servants
 of the people4 ,in political life the  
obligations it imposes are already very 
generally recognized2 and still more    
strongly are they felt by the ministers 
of religion4 ,the politician who uses   
his high position to promote his        
personal interests may sometimes escape 
his just deserts2 but the clergyman who 
prostitutes his influence for private   
gains is universally condemned4 ,so true
 is this1 that a clergyman is debarred  
by his profession from many of the      
industries and occupations of life which
 are regarded as perfectly honorable    
callings for other men4 ,a clergyman who
 speculated in stocks1 or even engaged  
in a mercantile pursuit1 would1 with    

good reason1 lose the respect of the    
very men who had gained their wealth by 
the same ways which they deny to him4   
,he may not1 like the members of the    
elder religious fraternities1 take the  
vow of poverty1 but still he is held to 
a very strict rule of life2 and on this 
is based his claim to an adequate       
support from the people to whom he      
ministers4 ,because appointed to sow    
spiritual things1 the clergy are        
entitled to reap worldly things which   
they have not sown nor gathered2 and    
evil will be the days when this claim is
 disallowed4  ,now1 we hold that the    
profession of a scientific teacher      
implies an obligation not less binding  
than that which rests on the clergyman2 
and this is especially true if the      
teacher has been placed in a conspicuous
 and responsible position before the    
world4 ,the teacher has been set apart  
as truly as the clergyman1 and1 if he   
uses the influence of his office merely 
as a means of accumulating wealth1 he is

 not loyal to the profession which he   
has voluntarily assumed4 ,let me not be 
misunderstood4 ,there are a thousand    
legitimate ways of earning a livelihood 
and acquiring wealth by means of the    
knowledge which scientific study gives2 
and a man has a right to use scientific 
knowledge for his worldly advancement as
 freely as any other knowledge4 ,but the
 man who has accepted the post of a     
teacher1 and receives the support to    
which his position entitles him1 is     
bound to do the work of a teacher to the
 best of his ability1 and to devote his 
whole energies to extending the         
knowledge of the science which he       
professes to teach4 ,it is of the utmost
 importance that the community should be
 educated up to this point1 and should  
hold its teachers to their trusts and   
obligations as strictly as it does its  
clergy4 ,indeed1 the scientific even    
more than the religious teacher requires
 the aid of a correct public sentiment  
to maintain the tone of his profession4 

,scientific knowledge and acumen1 when  
centered on business relations1 has     
often discovered direct avenues to      
wealth2 the temptation to make use of   
the opportunities thus offered is of    
course very great1 and in most of the   
relations of life the career so opened  
may be perfectly legitimate and         
honorable4 ,but no one can expect to    
succeed in any business career without  
devoting his whole energy to the work1  
and there are conditions under which    
such a course would involve the betrayal
 of a trust4 ,nor are the words betrayal
 of a trust too strong2 for it is       
sometimes the case that1 besides        
neglecting his appropriate work1 the    
scientific teacher sells the reputation 
of his position1 and commands a higher  
price because he barters the good name  
of the institution with which he is     
connected4  ,i am well aware that there 
is another side to this question4 ,in   
many of our colleges the professor has  
an inadequate support1 and is expected  

or even invited to supplement his income
 by what is technically called          
commercial work4 ,of course1 in such    
cases the man can not be blamed2 but    
public opinion should be such as to     
prevent a respectable institution from  
offering1 or a respectable professor    
from accepting1 such a position4 ,the   
workman is worthy of his hire1 and the  
same sentiment which demands from the   
scientific professor a whole-hearted    
devotion to his work1 demands also from 
the community for which he works an     
adequate support4  ,it is undoubtedly in
 consequence of the inadequate support  
which scientific teachers generally     
receive in this country that public     
sentiment tolerates with them practices 
which sober judgment must condemn2 and  
it must be remembered that under these  
circumstances a teacher1 if he is       
faithful to the routine of his office1  
may devote his remaining energies to    
commercial work1 not only without any   
consciousness of wrong-doing1 but even  

with the approbation of his associates4 
,hence1 it is the more important to     
establish firmly in the public mind the 
well-founded opinion that the endowed   
professorships of our higher            
institutions of learning are offices of 
public trust1 to be administered solely 
for the public good4 ,there is no       
hardship in this position2 since        
perfectly legitimate and honorable      
avenues are opened to the scientific    
scholar1 on which he may expend his     
business energies1 and1 at the same     
time1 use his scientific knowledge2 and 
for many men these avenues lead in the  
directions in which they can not only   
most effectually advance themselves in  
worldly prosperity1 but also most       
benefit their fellows4 ,among the men of
 practical ability who have developed a 
new industry1 or introduced a new       
invention1 and who have acquired wealth 
thereby1 are to be found some of the    
greatest benefactors of their race2 and 
far would it be from me to institute a  

comparison between the practical men and
 the scholars4 ,all we claim is that the
 men of affairs should resign the       
endowments intended for the maintenance 
of scholars to those whose zeal is      
sufficient to induce them to make gladly
 the sacrifices which the advancement of
 knowledge usually entails4  ,these     
considerations will appear still more   
forcible if viewed in relation to the   
interest of the community in scientific 
culture to which we have already        
referred4 ,this interest has not been   
overlooked1 and in recent years a great 
many projects have been discussed for   
what is termed the endowment of         
research2 and already very considerable 
funds are held by learned societies of  
the ,old ,world1 and smaller amounts by 
several societies of this country1 which
 have been devoted to this object4 ,but 
although means are thus furnished to a  
limited extent to pay the expenses of   
scientific investigations1 and very     
considerable prizes are offered for the 

solution of important problems1 yet it  
must be confessed that as yet the       
results have been meager and have not   
answered the expectations of the        
founders of the endowments2 and the     
reason of the small fruitage is not far 
to seek4 ,a certain order of scientific 
results can be purchased like other     
professional work for a price which is  
to some extent proportionate to the     
skill required to obtain them4 ,such1   
for example1 are the daily observations 
at an astronomical or a meteorological  
station2 such also are chemical analyses
 and assays of various kinds2 such1     
again1 is much of the routine work of a 
physical laboratory4 ,but the highest   
order of scientific results1 such as    
leave a permanent impress on the records
 of science--like ,newton's law of      
gravitation1 ,young's theory of light1  
,faraday's theory of electricity1 or    
,bunsen's methods of spectrum           
analysis--can no more be had to order   
than could ,paradise ,lost or ,in       

,memoriam have been purchased by the    
foot4 ,moreover1 scientific progress    
follows a necessary law of continuity1  
and important advances can not be made  
until the time is ripe4 ,the most that  
can be done with the direct endowments  
for research is1 to multiply trustworthy
 observations1 and thus prepare the way 
for discovery2 and more than this can   
not be expected4  ,a more efficient     
means of cultivating science1 and one   
which is certain1 in the long run1 to   
yield a far more abundant and richer    
harvest1 is to secure the conditions    
which are known to be favorable to      
scientific discoveries1 and to hold in  
honor such discoveries when made2 and ,i
 think there will be little difference  
of opinion among competent scientific   
authorities that the one essential      
condition above all others is a certain 
atmosphere which results from the       
association of men who are engaged in   
scientific study4  ,an association of   
scholars acts in many ways to favor     

either literary or scientific           
production4 ,in the first place1 it     
leads to competition1 which1 although a 
low motive1 is a very potent one in all 
forms of human activity4 ,in the second 
place1 the contact of minds engaged in  
similar studies leads the student to    
take a broader view of his subject1 and 
to see it from the various points of    
view which the criticism of his         
associates may point out4 ,above all1   
work done in such associations is not   
done without observation1 and there are 
present witnesses to attest the results1
 and publish them with the authority    
which is required to insure for them    
general acceptance4 ,a great deal of    
scientific work is lost to the world    
because done in a corner1 and buried in 
the transactions of local societies1    
from which it is not disinterred until  
the work has been repeated4 ,the        
advantages of such association are only 
too evident to the numerous workers in  
science at the isolated colleges of this

 country1 who are forced to compare     
their opportunities with those of their 
compeers in the great capitals of       
,europe2 and the want of scientific     
productiveness in the ,united ,states   
which we so greatly lament is due       
chiefly to the want of the stimulus     
which combined action so greatly gives4 
,happily1 however1 the conditions       
favorable for scientific investigation  
are multiplying at home1 and already    
there are several centers at which the  
productiveness is rapidly increasing1   
and gives great promise of the future4  
,moreover1 this growth gives us a good  
indication as to the points at which we 
can most advantageously apply aid2 and  
,i am confident that there is no way in 
which we can so effectively encourage   
scientific investigation as by          
establishing at the institutions of     
learning1 which are at present the chief
 centers of scientific activity1 more   
professorships and fellowships1 in order
 to give support to those who are ready 

to devote their lives to scientific     
study4  ,the teaching which a           
professorship implies1 instead of being 
a hindrance1 ought to be a great        
stimulus to scientific investigation4   
,of course1 this influence is greatly   
impaired if1 as in many of our colleges1
 the available energies of the teacher  
are exhausted by the daily routine of   
instruction1 or by the outside work     
required to supplement his meager       
salary4 ,but1 if the teaching is only   
moderate in amount and in the direction 
of the professor's own work1 there is no
 stimulus so great as that which the    
association with a class of earnest     
students supplies4  ,were it necessary  
to sustain the opinions here advanced by
 further illustrations1 we need only    
point to the ,royal ,institution of     
,great ,britain1 which holds foundations
 like those we have advocated2 for the  
names of ,davy1 ,young1 ,faraday1       
,tyndal1 and ,dewar1 are a conspicuous  
memorial of the very great success of   

such endowments in advancing physical   
science4  ,it is obvious1 however1 that 
the endowment of professorships and     
fellowships will be of no value to the  
community unless it is understood that  
the incumbents are set apart for their  
special work2 and the suggestion that   
such positions could be used to favor   
private ends1 or as the basis of        
mercantile transactions1 is sufficient  
to show how inconsistent such a practice
 is with the true conception of         
scientific culture4  ,our patent laws   
have a very marked and not altogether a 
beneficial influence on the scientific  
culture of the country4 ,it is true that
 they foster mechanical ingenuity and   
inventive talent in certain directions1 
but they also set before the people a   
very low and mercenary standard of      
scientific attainment1 upon which the   
popular notion of the utilitarian       
tendency of scientific studies is to a  
great extent based4 ,no one can question
 that the discoverer of a new process1  

or the inventor of a new machine1 has a 
right to keep his knowledge to himself1 
and to make the best use he can of his  
good fortune to increase his wealth4    
,but certainly the motto at the head of 
this essay points to a more excellent   
way1 and it is at least an open question
 whether it is for the interest of the  
community at large to encourage by its  
laws the more selfish course4 ,the      
argument by which the patent laws are   
usually defended by legal writers--that 
it is for the benefit of the community  
to encourage and therefore to protect   
inventive talent--is by no means so     
unanswerable as it appears prima-facie4 
,in the first place1 it may be          
questioned whether1 in the present      
condition of our patent laws1 they do   
not hinder more than they foster        
invention4 ,any one who has attempted to
 perfect a machine1 or improve a        
chemical process1 knows to what extent  
he is hampered on every side by patent  
rights1 which often have no value to the

 holders except that which the new      
improvement may give to them4  ,again1  
the inventions which the patent laws    
foster are only those having an         
immediate pecuniary value1 and it is    
often exceedingly simple                
contrivances--like the needle of a      
sewing-machine or a gaudy toy--which    
yield the greatest return2 simply       
because they have been accommodated to  
present emergencies or to passing       
popular fancy4 ,such contrivances       
usually manifest no extended knowledge  
and no special talent1 and the inventor 
owes his good luck to the sole          
circumstance that he was in a position  
to recognize the want4  ,now1 every     
scientific investigator knows that the  
ordinary work of a physical or chemical 
laboratory frequently demands inventive 
ability of a high order1 and that few   
important scientific results have been  
reached that have not involved          
inventions as worthy of admiration as   
the sewing-machines and power-looms     

which are so frequently cited as        
examples of the beneficent influence of 
our patent laws2 and the question       
arises1 is it for the interest of the   
community to promote one class of       
inventions more than the other8         
,certainly1 if we consider either the   
sacrifice involved1 or the ultimate good
 which eventually results to the        
community1 there can not be a moment's  
question which class is the most        
valuable or most worthy of commendation4
 ,yet the patent laws not only give     
their immense prizes solely to          
inventions of immediate utility1 but    
also tend to raise a false estimate of  
the intrinsic value of such inventions  
in the public mind4  ,some writers have 
gone to the extreme of claiming that a  
man has the same right in his inventions
 or discoveries that an author has in   
his books2 but this claim will not bear 
analysis4 ,the first duty of a          
government is to protect its citizens in
 the enjoyment of the results of their  

lawful labor1 and certainly any one who 
has written a book knows that it is just
 as much the product of day-labor as any
 article of merchandise4 ,on the other  
hand1 an invention or discovery may be  
the result of a fortunate accident1 and1
 although it may be the fruit of        
superior knowledge and intelligence1 it 
can not be regarded in the same sense as
 a direct product of labor4 ,it is much 
more frequently a free gift of ,nature4 
,moreover1 it is seldom if ever the case
 that a useful invention1 meeting a     
popular want1 and therefore having a    
large commercial value1 is in any sense 
the product of one man4 ,as a general   
rule1 the patentee who enjoys the right 
to the invention has actually added to  
the old stock only a single detail4 ,it 
may be that this detail was the one     
thing required to make the invention    
practically useful2 but it is certain   
that the addition could never have been 
made if the previous knowledge had not  
existed1 and it is at least an open     

question whether the community ought to 
grant to the last man an exclusive right
 to the whole inheritance4 ,volta       
discovered--invented1 if you please--the
 mode of generating a current of        
low-tension electricity1 which has been 
ever since1 with certain modifications1 
in general use2 ,oersted and ,ampere    
discovered the magnetic effects of this 
electrical current2 ,faraday1 again1    
learned how to produce an electric      
current from a magnet1 and invented the 
original dynamo-machine2 ,henry         
discovered the conditions under which   
the magnetic effects of an electric     
current might be produced at great      
distances from the source of the power4 
,all these men were inventors of the    
highest order1 whose inventions have    
never been excelled either in the       
ingenuity displayed1 or in the influence
 exerted on the welfare of mankind4     
,moreover1 these far-reaching inventions
 were a willing contribution to the     
world's knowledge1 for which no         

pecuniary compensation was either asked 
or received4 ,is it not1 then1 a        
question if any man of the present day  
has a right to the exclusive use of     
these inventions2 for writing messages  
at a distance1 for transmitting sound   
over wires1 or for any purpose          
whatsoever8  ,there is of course another
 side to the question1 and ,i freely    
admit the difficulty of the problem     
which our patent laws present2 but ,i   
feel that in their present condition    
they do more harm than good1 and do     
injustice more frequently than they     
protect right4 ,i greatly doubt if it is
 safe to grant by statute property in   
any invention or discovery beyond the   
definite mechanical contrivance in which
 it is for the time embodied4 ,to grant 
the sole use of a well-known power of   
,nature to produce a specific effect1   
although the effect be a novel one2 to  
give the monopoly of a process of       
,nature to the man who was the first to 
claim it2 above all1 to grant the sole  

right to make a specified mixture of    
materials--is certainly a policy which  
directly encourages vast monopolies1    
that tax the public without rendering a 
corresponding benefit4  ,in this        
connection it must be remembered that   
the discoverer or inventor himself      
rarely reaps the fruit of his sagacity  
or skill2 but his rights1 frequently    
purchased for a song1 are made the basis
 of great business enterprises in which 
he has little or no share4 ,on such a   
slender basis have frequently been built
 up huge monopolies1 in which the patent
 laws have been made the instruments of 
oppressive exactions1 and have become   
the nucleus of a most complex system of 
usages and legal decisions1 by which the
 original intent of the laws has been   
wholly overlaid1 and to a great extent  
nullified4  ,certainly1 there ought to  
be some limit to the inventor's claims  
on a grateful people4 ,admit to the     
utmost the inventor's merit2 rank him in
 the fore front of the long procession  

of the great benefactors of the human   
race2 rank him before ,faraday1 before  
,volta1 and before ,newton2 rank him    
before ,washington and the ,fathers of  
the ,republic2 rank him before the      
patriots and martyrs who have died in   
the defense of human rights1 or in      
attestation of the truth3 and yet1 in   
virtue of these transcendent merits1    
should he or his representatives be     
authorized to tax his countrymen        
millions on millions of dollars a year8 
,surely1 there could not be a greater   
travesty of our motto1 ,noblesse        
,oblige2 and a system which gives a     
legal sanction to such abuses will soon 
force on the public mind that most      
convincing of all proofs of perversion1 
the reductio ad absurdum4  ,it is not1  
however1 our intention to discuss the   
abuses of the patent laws1 much less to 
suggest the required remedies4 ,we      
clearly see the difficulties of the     
subject1 and we perceive that it        
involves questions1 both of political   

economy and of jurisprudence1 with which
 we are not competent to deal4 ,our     
interest is solely to maintain the      
dignity of scientific culture1 and to   
demand for it the respect to which it is
 entitled2 but which is seriously       
compromised by the mercenary and        
utilitarian spirit that the patent laws 
encourage and make prominent4 ,we are   
most anxious that the intelligence of   
our people should fully recognize the   
fact that1 among the students of science
 in this practical age1 there is such a 
thing as devotion to the truth for the  
truth's sake2 that throughout the length
 and breadth of these ,united ,states   
may be found many an earnest student of 
,nature who1 under great disadvantages1 
and often at great personal sacrifice1  
is devoting the noblest intellectual    
power1 and the highest inventive skill1 
to the sole end of advancing knowledge3 
and we rejoice to believe that the time 
will come when it will be plainly seen  
by all that these silent workers have   

been laying broad and deep-enduring     
foundations1 on which national greatness
 can securely rest4     ,,xiii4  ,,the  
,,spiritual ,,life4,q   ,we have reached
 the end of our long journey1 and now we
 are ready to turn back and start for   
home4    ,q ,an ,address to ,college    
,students at the close of a course of   
lectures on ,egypt and her ,monuments4  
,illustrated by lantern                 
photographs4  ,the ,reis is at his helm1
 the great sail is furled and bound     
closely to the long yard2 for1 as the   
wind during the early spring blows here 
constantly from the north1 we must      
depend on the rapid current of the ,nile
 to bear us back to civilization3 a     
river which1 flowing through so many    
generations of men from the unknown to  
the unlimited1 not unfitly typifies the 
course of history2 and as1 in           
imagination1 we drift with this         
historical stream1 we can not fail to   
learn the lesson which the associations 
and the scenes are so calculated to     

teach4 ,that lesson is the grandeur1 the
 glory1 and the immortality of the      
spiritual life of man4  ,we go back six 
thousand years1 and find the ,sphinx1 as
 to-day1 looking toward the rising sun1 
and pondering the problem of human      
destiny4  ,the pyramid-builders come1   
and erect those neighboring piles to    
preserve their bodies when dead for that
 glorious destiny in which they trust4  
,the long procession of the ,pharaohs   
passes1 and each inscribes indelibly on 
rocky walls his faith in the great ,god 
who holds human destiny in his hands4   
,moses comes1 and leads out of ,egypt   
the chosen people to prepare the way for
 the expected ,messiah4  ,the ,assyrians
 and the ,persians come1 and1 while     
seeking to read their destiny in the    
courses of the stars1 pay homage to the 
same great hope4  ,the ,greeks come1    
and1 even amid gross licentiousness and 
idolatry1 erect magnificent temples1 in 
attestation of a belief in human destiny
 which1 however degraded1 still         

survived4  ,the ,romans come1 and in    
this mystic land lay aside their legal  
codes1 and add their testimony to the   
same great truth4  ,the ,christian      
hermits come1 and make the storied      
stones of the ,pharaohs re-echo with    
their triumphant songs4  ,the ,arab     
comes1 and1 as morning and evening he   
gazes into the ,east1 sees visions of   
the glorious ,mecca of his hopes for    
which the ,sphinx has looked so long4   
,last of all1 the modern traveler comes1
 and he journeys in vain if he does not 
recognize in all this aspiration and all
 this yearning the attestation of those 
spiritual truths which to him the risen 
,christ has revealed4  ,as in material  
nature every unemployed organ distinctly
 points to a previous use or to a future
 fruition3 so1 in the spiritual world1  
every striving is a promise of a        
possible good2 and these yearnings of   
humanity1 which have come down through  
the ages1 are as truly a promise of the 
,eternal as were the words spoken to    

,abraham on the plains of ,mamre4       
,coming home from the ,east1 we can not 
fail to see1 more clearly than before1  
how artificial are most of the          
conventionalities of our modern         
civilization1 and how greatly such cares
 of the world tend to obscure the great 
distinction between the spiritual and   
the material which is ever present to   
,oriental thought2 and this is          
especially true in our own country1     
where the demands of material nature are
 so pressing1 and where the physical    
wants1 which our highly artificial life 
entails1 so completely engross the      
attention of us all4  ,it is well to go 
away at times1 that we may see another  
aspect of human life1 which still       
survives in the ,east1 and to feel that 
influence which led even the ,christ    
into the wilderness to prepare for the  
struggle with the animal nature of man4 
,we need something of the experience of 
the anchorites of ,egypt to impress us  
with the great truth that the           

distinction between the spiritual and   
the material remains broad and clear1   
even if with the scalpel of our modern  
philosophy we can not completely dissect
 the two2 and this experience will give 
us courage to cherish our aspirations1  
keep bright our hopes1 and hold fast our
 ,christian faith until the consummation
 comes4  ,my young friends1 there are   
many who will tell you that the ,sphinx 
has merely propounded a riddle to the   
ages2 and that the yearnings of your    
young lives--like those of the early    
,egyptians1 who set up this memorial of 
their hopes--are merely a delusion and a
 snare4  ,do not believe in any such    
pessimism4  ,it is merely the dying gasp
 of your animal nature6 ,but give your  
utmost efforts that these aspirations be
 not smothered by the cares and trials  
which must come to you as they come to  
all4  ,have faith in the ,eternal who   
implanted those cravings in your nature2
 and remember that all knowledge rests  
on the assurance that the ,eternal can  

not be false4 ,be loyal to the truth of 
that witness in your hearts1 and        
advancing years will only bring you     
increased reliance on the promises he   
ever whispers to those who trust him2   
and he will certainly lead you1 at      
last--as he has led the faithful in all 
ages--into the clear light of the       
perfect day4  ,my fellow-students1 if   
these fleeting pictures of scenes which 
have given me fresh courage1 shall aid  
any of you in the conflict of life1 my  
object in these lectures will be gained1
 and however incongruous with the       
associations of physical science such   
scenes may have appeared1 you will bear 
me witness that the great lesson they   
teach has constantly been enforced in   
this place4 ,the spiritual life of man  
recognizes its exalted intellectual     
likeness in the life of ,nature1 and it 
is this vision of the ,omniscient which 
distinguishes and ennobles mental       
culture1 whether it be in the fields of 
science1 of literature1 or of art4      

,,the ,,end4          99       99       
99       99       99   ,,scientific     
,,lectures ,,and ,,essays4    ,popular  
,lectures on ,scientific ,subjects4 ,by 
,h4 ,,helmholtz1 ,professor     of      
,physics in the ,university of ,berlin4 
,first ,series4 ,translated by     ,e4  
,,atkinson1 ,ph4 ,d41 ,f4 ,c4 ,s4 ,with 
an ,introduction by ,professor          
,,tyndall4 ,with #ea ,illustrations4    
#abmo4 ,cloth1 #b4jj4                   
,,contents4--,on the ,relation of       
,natural ,science to ,science in        
,general4--,on ,goethe's ,scientific    
,researches4--,on the ,physiological    
,causes of ,harmony in ,music4--,ice and
 ,glaciers4--,interaction of the        
,natural ,forces4--,the ,recent         
,progress of the ,theory of             
,vision4--,the     ,conservation of     
,force4--,aim and ,progress of ,physical
 ,science4    ,popular ,lectures on     
,scientific ,subjects4 ,by ,h4          
,,helmholtz4 ,second     ,series4 #abmo4
 ,cloth1 #a4ej4                         

,,contents4--,gustav ,magnus4--,in      
,memoriam4--,the ,origin and            
,significance of ,geometrical           
,axioms4--,relation of ,optics to       
,painting4--,origin of the ,planetary   
,system4--,on ,thought in               
,medicine4--,academic ,freedom in       
,german ,universities4      ,professor  
,helmholtz's second series of ',popular 
,lectures on     ,scientific ,subjects' 
forms a volume of singular interest and 
value4     ,he who anticipates a dry    
record of facts or a sequence of        
immature     generalization will find   
himself happily mistaken4 ,in style and 
method these discourses are models of   
excellence1 and1 since they     come    
from a man whose learning and authority 
are beyond dispute1     they may be     
accepted as presenting the conclusions  
of the best     thought of the times in 
scientific fields4--,boston ,traveler4  
,science and ,culture1 and other        
,essays4 ,by ,professor ,t4 ,h4         
,,huxley1     ,f4 ,r4 ,s4 #abmo4 ,cloth1

 #a4ej4      ,of the essays that have   
been collected by ,professor ,huxley in 
this     volume1 the first four deal    
with some aspect of education4 ,most of 
the remainder are expositions of the    
results of biological     research1 and1
 at the same time1 illustrations of the 
history of     scientific ideas4 ,some  
of these are among the most interesting 
of     ,professor ,huxley's             
contributions to the literature of      
science4--,london ,academy4      ,it is 
refreshing to be brought into converse  
with one of the most     vigorous and   
acute thinkers of our time1 who has the 
power of     putting his thoughts into  
language so clear and forcible4--,london
     ,spectator4    ,scientific         
,culture1 and other ,essays4 ,by        
,,josiah ,,parsons ,,cooke1             
,professor of ,chemistry and ,mineralogy
 in ,harvard ,college4 #abmo4           
,cloth1 #a4jj4      ,these essays are an
 outcome of a somewhat large experience 
in     teaching physical science to     

college students4 ,cambridge1           
,massachusetts1 early set the example of
 making the student's own               
observations in the laboratory or       
cabinet the basis of all     teaching1  
either in experimental or natural       
history science2 and     this example   
has been generally followed4 ,but in    
most centers of     education1 writes   
,professor ,cooke the old traditions so 
far     survive that the great end of   
scientific culture is lost in           
attempting to conform even laboratory   
instruction to the old     academic     
methods of recitations and examination4 
,to point out this     error1 and to    
claim for science-teaching its          
appropriate methods1     was one object 
of writing these essays4   ,,works ,,on 
,,astronomy4    ,elements of ,astronomy4
 ,by ,,robert ,,stowell ,,ball1 ,,ll4   
,d41 ,f4 ,r4 ,s41     ,andrews          
,professor of ,astronomy in the         
,university of ,dublin1 ,royal          
,astronomer of ,ireland4 ,with          

,illustrations4 #afmo4 ,cloth1 #b4be4   
,elementary ,lessons in ,astronomy4 ,by 
,j4 ,,norman ,,lockyer1 ,f4 ,r4 ,s4     
,richly illustrated1 and embracing the  
,latest ,discoveries4 ,american         
edition4 ,adapted to the ,schools and   
,academies of the ,united ,states4      
#abmo4 ,cloth1 #a4ej4    ,outlines of   
,astronomy4 ,by ,sir ,j4 ,j4 ,w4        
,,herschel4 ,with ,plates and           
,woodcuts4 ,eleventh edition4 #hvo4     
,cloth1 #d4jj4    ,the ,sun4 ,by ,c4 ,a4
 ,,young1 ,ph4 ,d41 ,,ll4 ,d41          
,professor of ,astronomy     in the     
,college of ,new ,jersey4 ,with numerous
 ,illustrations4 #abmo4     ,cloth1     
#b4jj4      ,professor ,young is an     
authority on ',the ,sun1' and writes    
from     intimate knowledge4 ,he has    
studied that great luminary all his     
life1 invented and improved instruments 
for observing it1 gone     to all       
quarters of the world in search of the  
best places and     opportunities to    
watch it1 and has contributed important 

discoveries that have extended our      
knowledge of it4--,popular     ,science 
,monthly4    ,spectrum ,analysis1 in its
 ,application to ,terrestrial           
,substances1     and the ,physical      
,constitution of the ,heavenly ,bodies4 
,familiarly     explained by ,dr4 ,h4   
,,schellen1 ,director der ,realschule   
,i4 ,o4 ,cologne4     ,translated from  
the second enlarged and revised ,german 
edition by     ,,jane and ,,caroline    
,,lassell4 ,edited1 with ,notes1 by     
,,william ,,huggins1     ,,ll4 ,d4 ,with
 numerous ,woodcuts1 ,colored ,plates1  
and ,portraits2 also1     ,angstroem's  
and ,kirchhoff's ,maps4 #hvo4 ,cloth1   
#f4jj4      ,this admirable work does   
credit to1 or should we say is worthy   
of1     the author1 the translators1 and
 the editor4 ,the first part treats     
on the artificial sources of high       
degrees of heat and light2 the          
second on ,spectrum ,analysis in its    
application to the heavenly     bodies4 
,we must approve the method followed in 

the translation and     by the editor4  
,in many translations the views of the  
author are     suppressed1 in order that
 the views of the translator or editor  
may     be expounded2 but here ,dr4     
,huggins1 however leniently such a fault
     might have been looked upon with   
him1 has permitted the author's         
views to remain intact1 clearly stating 
his own and wherein lies     the        
difference4--,the ,chemical ,news4      
,certainly1 as regards mere knowledge1  
the ',spectrum ,analysis' has     let us
 into many secrets of the physical      
universe which ,newton and     ,laplace 
would have declared impossible for man's
 intellect to     attain4 ,the science  
is still in its infancy1 but it is      
prosecuted     by some of the ablest1   
most patient1 and most enthusiastic     
observers1 and some of the keenest      
thinkers1 at present existing     on our
 little1 insignificant physical         
globe4--,boston ,globe4    ,studies in  
,spectrum ,analysis4 ,by ,j4 ,,norman   

,,lockyer1 ,f4 ,r4 ,s41                 
,correspondent of the ,institute of     
,france1 etc4 ,with ,sixty              
,illustrations4 #abmo4 ,cloth1 #b4ej4   
,the study of spectrum analysis is one  
fraught with a peculiar     fascination1
 and some of the author's experiments   
are exceedingly     picturesque in their
 results4 ,they are so lucidly          
described1 too1     that the reader     
keeps on1 from page to page1 never      
flagging in     interest in the matter  
before him1 nor putting down the book   
until     the last page is              
reached4--,new ,york ,evening ,express4 
,origin of the ,stars1 and the ,causes  
of their ,motions and their ,light4     
,by ,,jacob ,,ennis4 #abmo4 ,cloth1     
#b4jj4    ,astronomy and ,geology       
,compared4 ,by ,lord ,,ormathwaite4     
#ahmo4 ,tinted     paper4 ,cloth1 #a4jj4
    ,the ,expanse of ,heaven4 ,a ,series
 of ,essays on the ,wonders of the      
,firmament4 ,by ,r4 ,a4 ,,proctor4      
#abmo4 ,cloth1 #b4jj4      ',the        

,expanse of ,heaven' can not fail to be 
of immense use in     forwarding the    
work of education1 even when it is read 
only for     amusement1 so forcible is  
the impression it makes on the mind from
     the importance of the subjects     
treated of1 while the manner of         
treatment is so good4--,boston          
,traveller4    ,the ,moon3 ,her         
,motions1 ,aspect1 ,scenery1 and        
,physical ,conditions1 with     ,two    
,lunar ,photographs and many            
,illustrations4 ,by ,r4 ,a4 ,,proctor4  
,new     edition4 #abmo4 ,cloth1 #c4ej4 
,other ,worlds than ,ours2 the          
,plurality of ,worlds1 studied under the
     ,light of ,recent ,scientific      
,researches4 ,by ,r4 ,a4 ,,proctor4     
,with     ,illustrations1 some colored4 
#abmo4 ,cloth1 #b4ej4    ,our ,place    
among ,infinities4 ,a ,series of ,essays
 contrasting our ,little     ,abode in  
,space and ,time with the ,infinities   
around us4 ,to which are     added      
,essays on the ,jewish ,sabbath and     

,astrology4 ,by ,r4 ,a4 ,,proctor4      
#abmo4 ,cloth1 #a4ge4   ,,works ,,on    
,,geology1 ,etc4    ,principles of      
,geology2 or1 ,the ,modern ,changes of  
the ,earth and its     ,inhabitants1    
considered as illustrative of ,geology4 
,by ,sir ,,charles     ,,lyell1 ,bart4  
,illustrated with ,maps1 ,plates1 and   
,woodcuts4 ,a new and     entirely      
revised edition4 #b vols4 ,royal #hvo4  
,cloth1 #h4jj4      ,the ,principles of 
,geology may be looked upon with pride1 
not only     as a representative of     
,english science1 but as without a rival
 of     its kind anywhere4 ,growing in  
fullness and accuracy with the growth   
of experience and observation in every  
region of the world1 the work     has   
incorporated with itself each           
established discovery1 and has     been 
modified by every hypothesis of value   
which has been brought     to bear upon1
 or been evolved from1 the most recent  
body of facts4    ,text-,book of        
,geology1 for ,schools and ,colleges4   

,by ,h4 ,,alleyne     ,,nicholson1 ,m4  
,d4 #abmo4 ,half roan1 #a4cj4    ,the   
,ancient ,life-,history of the ,earth4  
,a ,comprehensive ,outline     of the   
,principles and ,leading ,facts of      
,palaeontological ,science4     ,by ,h4 
,,alleyne ,,nicholson1 ,m4 ,d4 ,with    
numerous ,illustrations4     ,small     
#hvo4 ,cloth1 #b4jj4    ,elements of    
,geology4 ,a ,text-,book for ,colleges  
and for the ,general     ,reader4 ,by   
,,joseph ,,le ,,conte1 ,,ll4 ,d41       
,professor of ,geology and     ,natural 
,history in the ,university of          
,california4 ,with upward     of #ijj   
,illustrations4 ,revised and enlarged   
edition4 #abmo4     ,cloth1 #d4jj4      
,town ,geology4 ,by the ,rev4 ,,charles 
,,kingsley1 ,f4 ,l4 ,s41 ,f4 ,g4 ,s41   
,canon of ,chester4 #abmo4 ,cloth1      
#a4ej4    ,the ,study of ,rocks4 ,an    
,elementary ,text-,book in ,petrology4  
,with     ,illustrations4 ,by ,,frank   
,,rutley1 of the ,english ,geological   
,survey4     #afmo4 ,cloth1 #a4ge4      

,great ,ice ,age1 and its ,relation to  
the ,antiquity of ,man4 ,by ,,james     
,,geikie4 ,with ,maps and               
,illustrations4 #abmo4 ,cloth1 #b4ej4   
,volcanoes3 ,what they ,are and what    
they ,teach4 ,by ,j4 ,w4 ,,judd1        
,professor of ,geology in the ,royal    
,school of ,mines 7,london74     ,with  
#if ,illustrations4 #abmo4 ,cloth1      
#b4jj4    ,climate and ,time in their   
,geological ,relations3 ,a ,theory of   
,secular     ,changes of the ,earth's   
,climate4 ,by ,,james ,,croll1 of ,h4   
,m4 ,geological     ,survey of          
,scotland4 ,with ,maps and              
,illustrations4 #abmo4 ,cloth1 #b4ej4   
,geology4 ,by ,professor ,,archibald    
,,geikie1 ,f4 ,r4 ,s4 7,science         
,primers47     #ahmo4 ,flexible cloth1  
#de cents4   ,for sale by all           
booksellers2 or sent by mail1 post-paid1
 on receipt of price4   ,new ,york3 ,d4 
,,appleton  ,,co41 #a1 #c1  #e ,bond    
,street4          99       99       99  
99       99     ,,transcriber',s ,,notes

   #a4 ,passages in italics are         
surrounded by underscores4  #b4         
,footnotes have been reindexed and moved
 from the end of the page to the closest
 paragraph break4  #c4 ,certain words   
use oe ligature in the original4  #d4   
,carat character 77 is used to indicate 
raised to power4 ,and the underscore    
character 77 is used to represent       
subscript4  #e4 ,the greek letter alpha 
is represented as alpha in this text4   
#f4 ,a mixed fraction is indicated with 
a hyphen and forward slash4 ,for        
example1 #c-a_/b represents three and a 
half4  #g4 ,the following misprints have
 been corrected3     #a_/jjjj corrected 
to #a_/ajjj 7page #aaa7     strucure    
corrected to structure 7page #aci7      
fevric corrected to ferric 7page #ada7  
d'antorite corrected to d'autorite 7page
 #ahh7     resourses corrected to       
resources 7page #bjf7  #h4 ,other than  
the corrections listed above1 printer's 
inconsistencies in spelling1            
punctuation1 and ligature usage have    

been retained4