1890.] MICKOSCOPICAL JOURNAL. 107 



Annuiil Address before the Wasliingtoii Microscopical Society 

 delivered at its Soiree for 1890. 



By E. a. BALLOCH, M. D., 



WASHINGTON, D. C. 



The Microscopical Society welcomes you to its Sixth Annual Soiree. 

 That these meetings are occasions of interest and profit to the general 

 public is shown by the large and increasing attendance upon them. 

 We are glad to see you once a year, but we should be more glad to know 

 that your interest in the microscope was perennial and not annual. The 

 amount of time and trouble necessary to the successful conduct of one 

 of these soir(^es can only be appreciated bv those upon whom the labor 

 devolves. But we are not wholly free from selfish motives in this matter. 

 We hope, by means of these meetings, to add recruits to the increasing 

 army of users of the microscojoe, and to familiarize you with this most 

 fascinating of instruments. 



Many, doubtless the most, of 30U view the microscope with a feeling 

 somewhat akin to awe. It appears to you a mysterious instrument, 

 capable of revealing wondrous things and not to be handled by the un- 

 initiated. 



The glittering array of polished brass and shining lenses makes you 

 feel that years of study and preparation must be necessary to the suc- 

 cessful use of this instrument. 



Nothing could be further from the truth, and it is my purpose to-night, 

 in a brief way, to divest your minds of some popular errors with regard 

 to the microscope, and to indicate to you what may be done with a 

 comparatively inexpensive instrument, and a limited number of acces- 

 sories. 



No man has done more for the art of microscopy than Leeuwenhoek, 

 a Dutch scientist, who lived and worked in the latter part of the seven- 

 teenth century. All his observations were made with simple globules 

 of glass, ground and polished by himself, and set in brass frames. Yet, 

 with this primitive apparatus, he made observations which are inarvels 

 of accuracy, and many of his descriptions are as true to-day as when he 

 made them, two hundred years ago. But, you will doubtless say, I 

 have neither the time, patience, nor ability to make microscopes like 

 Leeuwenhoek, nor can I, in view of the limited use I should make of it, 

 afibrd to purchase a costly instrument like those I see here. The an- 

 swer to these objections is easy : You need do neither. 



All manufiicturers of microscopes make instruments, moderate in 

 price, with which you may do work from which you may derive an 

 abundance of profit and entertainment. 



But, I hear someone say, after all it will be but a mere toy and of no 

 lasting benefit. This is a stock criticism on the use of the microscope, 

 and, like many of its class, based upon no solid foundation. I will cite 

 you a few instances out of many, in which the microscope may be use- 

 ful in every-day life, and let them answer this objection. 



We will assume that you are about to order a suit of clothes, or your 

 wife a dress from a piece of goods which is represented to you as 

 " strictly all wool." You take a sample home with you and place a 

 few fibres under the microscope. If, perchance, you see two fibres of 

 cotton to one of wool you may be reasonably sure that you are the vie- 



