242 



[Vol. XXII. No. 561 



ment and write a complete and satisfactory report, there 

 would be found outlined, as above, sufficient for three 

 terms or one j'ear's work. 



For mechanical engineers the field must be broadened 

 out so as to include the various classes of prime movers, 

 engines, boilers, gas engines, etc. ; but in this case as in 

 the other, with a few small j)ieces of apparatus, and a few 

 accurate measuring instruments, a great number of useful 

 and valuable experiments can be performed. 



For the purpose of investigation and study, a tool or 

 machine rejected for inefficiency or wear by the owners, 

 will often serve as good a purpose as a new machine. 

 The results obtained often point out a line of practice 

 which should not be followed, and this becomes an endur- 

 ing lesson on the student's mind. 



I have elsewhere endeavored to point out in detail 

 methods of performing engineering experiments, and I 

 wish to call to mind here my emphatic opinion that so 

 far as educational results are concerned, the equipment 

 required need not be so expensive that it cannot be fur- 

 nished in any college of engineering in the country. It 

 is, perhaps, hardly necessary to remark that a little 

 apparatus, employed to advantage, is of more benefit than 

 a large collection used merely to adorn a cabinet or to 

 advertise a college. My own experience leads me to be- 

 lieve that no species of instruction is of as much value to 

 the student as that in Vi'hioh he participates, and knowl- 

 edge obtained by "feeling" it out, by proving by actual 

 experiment, remains with one and is more readily at com- 

 mand than that obtained purely through the senses of 

 sight and sound. 



This leads me to place a high value on this species of 

 instruction, but above and aside from all this is the fact 

 that engineering is an art, founded on imperfect applica- 

 tions of the science of mechanics; all that we get in this 

 line, every engineering truth, must be proved, if not orig- 

 inated,' by the laborious processes which are fii-st taught 

 in an engineering laboratory; and he who would advance 

 his profession mtist be skilled in all that relates to obser- 

 vation and investigation. 



ANIMAL BIOLOGY IN HIGH SCHOOLS AND 

 COLLEGES. 



BY W. X.IYIER SCDDUTH, A. M., JI. D., UNIVERSITY EXTENSION 



LECTUBEE AND PEOFESSOE OF EMBBYOLOGY, ETC., IN 



THE UNI.'. OF SIINNESOTA, MINNEAPOLIS, MINN. 



No one, at the present day, questions the importance of 

 animal biology in the curriculum of all well conducted 

 high schools and colleges as well as in the better en- 

 dowed universities and professional schools. The ques- 

 tion is rather, how maj this be accomplished ? That there 

 is a sad lack of competent instruction in these branches, 

 even in schools that make it their business to educate 

 teachers, cannot be denied. 



The need is only too a^jparent but the laboratory method 

 is not way the to remedy the defect in our smaller colleges 

 and high schools, because it is beyond their financial abili- 

 ty to secure it. 



This obstacle may. however, be overcome to a certain ex- 

 tent by the use of the stereopticon and lantern slides 

 which may be had at a cost that is within the reach of 

 any school board. The price of stereopticons has, within 

 the past few years, been materially reduced and the qual- 

 ity greatly improved, so that now a good working lantern 

 with suitable accessories for projecting photo-micrographs 

 on the screen, for ordinary class work, may be had for a 



sum as low as fifty dollars. Then again the'process of re- 

 producing histological subjects has of late been so devel- 

 oped that they may be had from almost all dealers in 

 school supplies at a nominal outlay. Yerj little has, how- 

 ever, been written upon this method of illustrating 

 lectui'es on physiologj' and hygiene in our public schools 

 and it is with this in view that I have undertaken the 

 present article. ^ 



I have no hesitancy in saying, at the outset, that a 

 better understanding of the histology of tissues can be 

 imparted to a greater number of students in a given space ■ 

 of time by this means than can be-obtained by the labor- 

 atory method. I do not desire to be understood as de- 

 crying the practical working laburalory. Where time and 

 equipment are sufficient no better method can be had for 

 studying biology in all its phases, but where either of the 

 above essentials is lacking the lantern becomes a valuable 

 substitute, and even where the laboratory method is em- 

 ployed I have found the lantern a very valuable adjunct 

 in imparting a general knowledge of the subject. As a 

 method of illustrating didactic lectures on histology I 

 consider it far ahead of charts. In its use the matter of 

 "personal equation" is reduced to the minimum, and it 

 carries a more vivid impression of the original tissue 

 because of the fact that it is a jjliotograph. In the use 

 of the lantern the educated senses are appealed to and 

 valuable time saved that in the laboratory method is 

 spent in learning the technique of the microscope which 

 in after years is of little avail unless the individual con- 

 tinues in practical Laboratory work. If the object sought 

 is the making of microscopists and original investigators 

 then use the laboratory method combined with the 

 lantern for class demonstration, but if time or equipment 

 is a desideratum the lantern will be found to be fully 

 adequate for good class instruction. Ten years' experience 

 as a teacher of biology leads me to sjseak thus positively 

 on this question. Trained in the best German labor- 

 atories I naturally followed their methods when I began 

 teaching. Gradually the lantern was introduced to il- 

 lustrate didactic lectures. At first use was made of the 

 oxyhydrogen lime light for projecting actual tissues upon 

 the screen. Many valuable specimens were lost by over- 

 heating. Various cells were introduced to prevent this, 

 but they shut off the light to such an extent as to mini- 

 mize the result desired to be obtained. I was led to sub- 

 stitute solar light for the lime light, but the uncertainty 

 of the results led to its abandonment in favor of photo- 

 micrography, and now with an inexpensive oil lantern 

 better results are obtained by this j)rocess than formerly 

 with the most expensive stereopticons, under the most 

 favorable conditions. I make my own photomicrographs 

 and find it a delightful recreation. In past years I used 

 to keep on hand an extensive cabinet of microscopic 

 slides for reference. These have latterly been discarded ■ 

 for the photomicrographic negative. Mj custom now is 

 to photograph all points of especial value as I am study- 

 ing and file the negatives awaj' for future use. But little 

 time is required for the work when one has a dark room 

 handy which is fitted up for it. 



The objection has been offered to photomicrography in 

 that it only reproduced the slides in light and shade. To 

 overcome this objection I have invented a process by 

 which it is possible to reproduce the original stains of the 

 microscojDic slide in the lantern positive, in double stain 

 if necessary, and that without hand-painting as was 

 formerly required. 



In conclusion let me reiterate that by adopting the 

 lantern and photomicrography the subject of animal 

 biology may be successfully brought before the classes of 

 our high schools and colleges, now debarred from its 

 study by lack of suitable equipment. 



