The Microscope. 253 



erly cleared, and a low power objective, will answer the purpose in 

 view; but when the finest possible details of a histological or path- 

 ological specimen are sought by the aid of a high-power objective, a 

 section just thick enough to hold the tissue elements together will 

 not be too thin, — the thinner the better, provided the section has 

 been handled from beginning to end in the highest style of the 

 beautiful art. In other words: a very thin, evenly cut section— the 

 one three-thousandth of an inch — is of no more use or value than a 

 section the one-fiftieth of an inch thick if it, the thinner section, has 

 not been perfectly cleared up and well mounted ; and here, perhaps, 

 may have been the cause of your failure to appreciate " the large 

 number of mounts kindly sent" you by your subscribers? I, 

 myself, have received many worthless specimens ; never too thin, but 

 either too thick or badly cleared, often both; and they soon went 

 into turpentine to be cleaned for what the glass slips were worth. 



Prof. Stow ell says: "With the modern microtomes, it cannot be 

 regarded as any great skill to cut these fancy sections; while it does 

 take a fair amount of technical knowledge to properly interpret 

 what is in the field." 



I think I know something about section cutting with first-class 

 microtomes, having aised with entire satisfaction both the Bausch & 

 Lomb and Ryder machines ; but I made many discouraging mislicks, 

 and wasted a good deal of patient labor and cast-material before I 

 learned to cut " fancy sections." 



The proposition that it is the better knowledge to be able to 

 " interpret what is in the field " admits of no denial; but I submit 

 that while some persons excel in cutting and mounting, others in 

 reading the field which has been prepared for them, it is the combi- 

 nation of fine technique with ability to see and interpret which gives 

 the highest accomplishment in microscopical science. In no other 

 department of science, perhaps, does the old adage apply with 

 greater force — "a little knowledge is a dangerous thing." 



There is no short road even to ordinary skill in microscopy; and 

 if this be true, what of the years of patient steps required to reach 

 the highest ^ec/iwzgite and best knowledge on the subject? In the 

 hands of an expert operator with the microtome, the cutting of thick, 

 medium, or extremely thin sections, is simply a matter of choice. If 

 all the necessary conditions have been made present, namely : a per- 

 fect cast, a sharp knife, and a steady hand, the one is as easily cut 

 as the other. 



Evidently, Friedlander, when he wrote the words you have 

 quoted from his little book, was not familiar with the best methods 



