Journal of Applied Microscopy. 



19 



fore address our remarks to him to 

 whom the work, though not necessarily- 

 unknown, has not yet its full signifi- 

 cance. 



The botanist who finds in his cross- 

 country rambles a field of mullein and 

 fails to turn onto it his camera fails also 

 to pick up for his pupils a very instruc- 

 tive lesson on the "struggle for exist- 

 ence," and the "survival of the fittest." 

 The "Streamlet's bank in woodlands 

 dank" may furnish him abundant ma- 

 terial for evidence of adaptation to en- 

 vironment, as may also "Yon low tam'- 

 rack's needled swamp" from which this 

 "Streamlet's amber waters flow." A 

 photograph of the spreading beach tree 

 dropping its canopy of shade over the 

 beautiful, graceful clumps of Monotropa, 

 placed before the pupil, will awaken an 

 interest that the wood-cut in the text, 

 however well executed, can never 

 arouse. A picture of the pollen clouds 

 from a clump of nettle will arouse the 

 curiosity of the student to know the 

 mechanism by which such a striking 

 phenomenon is produced. 



But summer is not the only time when 

 the teacher of botany may use his cam- 

 era. When the leaves have dropped let 

 him photograph a few trees against a 

 clear sky, choosing an elm and a cotton- 

 wood; and then let him compare results 

 with the cuts in even that gem among 

 texts on elementary botany, Bergen. 



But granting that our cuts are perfect- 

 ly satisfactory or that we have very easy 

 access to all the trees whose method of 

 branching we wish the student to dis- 

 cuss, have we sections of all the forms 

 our text describes? We certainly wish 

 the student to gain his information first- 

 hand wherever possible, and hence we 

 have in many cases to substitute for the 

 form the text describes, another which 

 shows the same structures, differently 

 disposed, it may be. Where is our cut? 

 With our low-power objective we can 

 photograph almost every slide the stu- 

 dent of elementary botany should have 

 put into his hands. We make our own 

 cut. We would not urge that the photo- 

 graph may take the place of the dia- 

 grammatic or semi-diagrammatic draw- 

 ing that the student shall make, but only 

 that it shall complement it. It appears 

 to us self-evident that close questioning 

 from an accurate representation of what 

 the student sees and studies will be more 

 effective than will the quiz on his own 

 drawing. Ofttimes the photograph will 

 enable him to interpret his section w'ith 

 much less study and effort than he must 

 expend on the section alone to arrive at 

 the same result. For example, we give 

 to a student for study sections of the 

 rhizome of Pteris sp. From his text, 

 he determines, either before or after his 



drawing is made, that certain structures 

 he sees are scalariform vessels; but what 

 to make of those bridg'ing lines extending 

 from one wall towards or even to the 

 opposite, is more than he can tell. Now 

 as the photograph represents more ac- 

 curately than can the student with his 

 pencil, if he be given side by side the 

 photographs of the cross section and the 

 longitudinal, he will interpret much more 

 quickly from the former than from the 

 latter. Has he lost discipline by taking 

 the short cut to final results? Or to put 

 it differently, has he gained less by the 

 short cut? 



We need not multiply specific cases; 

 every active, earnest teacher can call 

 to mind instantly very many cases in 

 which a good photograph of a given sec- 

 tion in his possession would have been 

 of considerable assistance to himself 

 and not a little benefit to his students. 



There is nothing, absolutely nothing, 

 that will take the place of the diagram- 

 matic figure builded by the teacher be- 

 fore the eyes of the student in lecture or 

 class explanation; but when this work 

 has once been done how much more val- 

 uable is the photograph, the stereoptic 

 image projected upon the screen, if the 

 apparatus be at hand, or, in default 

 thereof, the bromide enlargement at 

 least. 



"No apparatus" need not be cried as 

 reason for not attempting some of this 

 work. A good low-power objective, 

 thirty-five cents for a dozen dry plates, 

 half that amount for developer and fix- 

 ing bath, an extemporized dark room, 

 some soup plates or some well made 

 wooden trays paraffined on the inside, a 

 wooden five-pound starch box, a few 

 ounces each of perseverance and inge- 

 nuity, are all that are absolutely essen- 

 tial for making a beginning. The writ- 

 er has yet some very creditable work 

 that was produced without the use of 

 more or better apparatus than is men- 

 tioned above. 



Most schools able to employ a teacher 

 of botany and a teacher of zoology or, 

 in place of the two, a teacher of general 

 biology, are able to have a well made 

 photographic outfit, and such should 

 have it. 



One caution only it seems necessary 

 to add. The use of high powers in mi- 

 cro-photography without the properly 

 adjustable apparatus, rigidly made, and 

 without objectives properly corrected for 

 the work, will result in complete and dis- 

 couraging defeat. 



In another issue of the Journal, 

 when time has allowed the making of 

 necessary cuts, some definite directions 

 how to do and what to use may be given 

 for such as need the help. 



Hillsdale College, Dec. 15, 1897. 



