256 The Microscope. 



at X, y, z, under the advantages of modern instruments and 

 able instructors. If so, let him take the lecturer's stand for a 

 twelye-month tour from Maine to Louisiana, and make each 

 lecture a " free and easy chat all around " with his audience, and 

 he will be plied with questions, even from many teachers and 

 professors of schools and colleges, revealing a darker and deeper 

 microscopical woods than the pathway trod by " Graybeard " in 

 his a, b, c, study of Pleurosigma angulatum. 



There is a something in the manipulating of a microscope 

 which it seems to be impossible to learn from books ; each must 

 work it out for himself, or become imbued with it by some pro- 

 cess of absorption or of imbibition, which seems to take place 

 when the novice sees the work done by one who can do it. Ver- 

 bally, I find it almost impossible to teach the handling of a high 

 angle, adjustable homogeneous immersion objective over test ob- 

 jects, yet the student readily " catches on " after seeing me do it, 

 although he protests that he is unconscious of doing anything 

 in his successful effort other than was done in his unsuccessful 

 ones. The student who struggles through the whole microscopi- 

 cal alphabet from A to izzard, will be better j)repared for original 

 work than one depending upon the absorption process of begin- 

 ning with X, y, z. The first turns out investigators ; the second,. 

 imitators. 



Let the student learn all he can from the brains of others, yet 

 if he does not make his own brain work he will never become a 

 microscopist. After he can show a clear, truthful resolution of 

 P. angulatum^ I consider he has learned the names of the letters 

 of his manipulative alphabet ; he must now combine them into 

 words and sentences. There are other stages to pass ;t he 

 era of A. pellucida, fine rulings bordering on the phvsical limits 

 of vision, etc., and I may still add another ; that of public lect- 

 ures, especially if conducted on the writer's method of " a free 

 chat all around with his audience." The mirror of which while 

 glaringly reflecting the microscopical ignorance of his audience, 

 will at times form diffraction images on his own brain, making 

 the balance of the lecture evening a sleepless night, either in 

 tossing from side to side on his bed, or bending over his tube 

 till the breakfast gong arouses him to the fact that he is only 

 mortal, be he ever so wise. 



New Orleans, La. Graybeard. 



