MICROSCOPE AND OPTICAL APPARATUS 9 



few of us can make a microscope; hence this 

 indispensable must be purchased, and should 

 be selected with the greatest care. Its first 

 cost may be whatever sum one chooses to 

 invest in it : after that, with proper care, its 

 cost for maintenance is nothing. The camera, 

 on the other hand, must be continually sup- 

 plied with food in the shape of sensitive plates. 

 Between the two, however, the earnest and 

 diligent worker will receive the reward of his 

 labors in the shape of more or less perfect 

 negatives, as his skill or lack of it can 

 produce. 



Microscopes specially designed for photo- 

 micrography, of superb workmanship and 

 combining every improvement and device cal- 

 culated to fit them for the highest grade of 

 work, may be had for a price. But it is not 

 with these we have to deal in this little book. 

 Following upon the lines indicated by its 

 title, I can do no more than simply refer to 

 them as being procurable if wanted ; every-day 

 instruments for busy workers must furnish 

 the materials for my illustrations of the begin- 

 nings of practical photo-micrography. The 

 optical requirements for microscopical research 

 and study in our leading colleges and schools 

 are now so thoroughly understood, and there 





