OF THB MICROSCOPE. 



ON THE SELECTION OF A MICROSCOPE FOR PRAC- 

 TICAL PURPOSES. 



The object of all the information given in the preceding 

 pages, is to enable the reader not only to understand and use 

 the microscope, but to select one judiciously; and, therefore, in 

 every section we have offered hints bearing in this direction. 

 "We now propose to give the reader such special instructions as 

 are necessary in addition to those previously offered. 



In selecting a microscope, regard must be had, not only to 

 the excellence of the instrument, but to its adaptability to the 

 purpose for which it is intended, and to the person who is to 

 use it. A complicated and expensive compound microscope, if 

 placed in the hands of a person having little experience or skill, 

 would evidently be worse than wasted, while to attempt to con- 

 duct elaborate and delicate investigations by means of a cheap 

 non-achromatic instrument, would simply be to throw away time, 

 and wantonly incur the risk of serious errors. And yet no mis- 

 take is more frequently made. A microscope is wanted; the 

 purchaser is liberal with his means, and he is saddled with an ex- 

 pensive instrument entirely unsuited to his requirements. Or, 

 on the other hand, a physican or student of limited means re- 

 quires an instrument, and being unable to afford the price of a 

 really good one, he is induced to purchase a cheap affair, whose 

 indications, when applied to the subjects for which he requires 

 it, are entirely unreliable; whereas, he ought to be told that if 

 he cannot afford a microscope with good objectives, he ought to 

 leave microscopy in its applications to medicine and physio- 

 logy alone. So, too, we often see compound microscopes sold 

 to students of elementary botany, when a cheap dissecting mi- 

 croscope is really what they need. 



It would be impossible to give anything like a list of special 

 nases in which the different styles of microscopes prove most 



