PART I . 



CHAPTEE I. 

 THE MICROSCOPE-STAND. 



As one looks through the catalogues of the various dealers, 

 and notices the microscope- stands varying in price from 2 

 to 40, a bewilderment as to what is essential and what is 

 not is the first feeling. We will, then, examine the parts, 

 describe their uses and advantages, and state what is 

 essential to a beginner. 



Here let us advise intending purchasers not to buy a 

 microscope unless it bears the name of a manufacturer : a 

 good workman is never ashamed of his handiwork. There 

 are many very inferior instruments that look tempting, but 

 a practical acquaintance with them soon discovers their 

 weak points and inefficiency. Happening to attend the 

 conversazione of a well-known microscopical society some 

 little time since, at which there were exhibited over one 

 hundred instruments, it was surprising to note the many 

 makeshifts of microscopes belonging to some of the exhi- 

 bitors and many of them had probably cost a fair price, 

 too. A manufacturer remarked to the writer that he was 

 some time since in a provincial town, when an auctioneer 

 asked him whether he could not make him up a job lot of 

 microscopes for sale by auction, as he was very successful 

 in disposing of a certain class of pictures in this way. The 

 disgust of the scientific workman can be better imagined 

 than described. The microscopes often seen in the novice's 

 possession seem to be of this genus. This kind of instru- 



