THE MICROSCOPE 



JULY, 1893. 



Number 7. New Series. 



THE GROWTH OF MICROSCOPY AND OPPORTUNI- 

 TIES OFFERED BY IT TO EARNEST STUDENTS. 



BY M. I. CKOSS, LONDON, ENGLAND. 

 (From Introduction to Modern Microscopy, London, 1893.) 



The history of the development of the microsope is exceed- 

 ingly interesting, and itself would fill a small volume : suffice 

 it to say that it was but sixty-eight years ago, or in 1824, that 

 Tully made the first achromatic microscope. Since that time, 

 step by step, such progress has been made in its construction 

 as would be scarcely realizable to those who have not followed 

 it. Ten years ago the President of the American Society of 

 Microscopists, in his annual address, remarked that lenses which 

 were believed to have so nearly reached the limit of perfection 

 fifteen years ago are antiquated now and the theoretical limit 

 of perfection has moved forward like the horizon and is as far 

 off as ever." The same statement applies to-day, and even 

 within the last five years, lenses have been placed at our dis- 

 posal by the leading opticians giving results that our microscop- 

 ical predecessors of fifteen or twenty years ago would never 

 have dreamed of; and still further experiments are going for- 

 ward, with the view of giving greater advantage in microscopical 

 research. What has been done in the lens parts of the micro- 

 scope has also been effected in the mechanical, and a far better 

 microscope can be purchased to-day for a given sum than a 

 few years ago could be obtained at nearly double the cost, bring- 

 ing that which was a luxury, and acquirable only by the 

 wealthy, within the reach of the slenderest purse. This is 



