1892.] THE MICROSCOPE. 133 



to devote himself to the intelligent study of the so-called practical 

 branches of medicine. 



As I have indicated, it is a mistake to suppose that for medical 

 purposes an expensive microscopical outfit is necessary. Neither 

 microscope nor objectives need be expensive. The stand should 

 be as simple as possible, but should also be well made. It 

 should be steady, not trembling at the least jar. The stage 

 should not be too high. Nearly all of the high-priced micro- 

 scopes made in the United States and England are, in my opinion, 

 open to this objection. If the stage is too high the hands easily 

 tire, a difference of half an inch in the height of the stage having 

 a very appreciable effect on the ease of manipulation. Clips 

 may be of advantage, or they may be a decided nuisance. They 

 should certainly be removable, and in all ordinary manipulations, 

 removed. Their only value is in fixing a preparation immov- 

 ablv in a definite position. * * * 



The combination of ocular ar.d objectives generally recom- 

 mended with microscopes is not the best for medical purposes. 

 Ordinarily two oculars (2 and i inch or i^ and ^ inch) and two 

 objectives (i and ^ inch, or f anrl 1-5 inch) are recommended. 

 Ol the combinations of oculars, the first mentioned is preferable. 

 It is seldom desirable to increase the magnification by means of 

 the eye-piece. Definition is not increased, although the apparent 

 size of the object is, and there is a loss of light and distinctness 

 which are not compensated for by the increased magnification. 



Neither of the combinations of objectives mentioned is advisable. 

 A combination of a ^ or ^ inch with a ^ inch is far preferable. 

 The first gives a sufficiently low power for ordinary purposes. It 

 can generally be divided, and then gives sufficiently distinct pict- 

 ures if very low power is necessary. For a high power for 

 medical purposes, the ^ or 1-5 inch does not give sufficient am- 

 plification, and the ^ is to be preferred. It must be remembered 

 that to be able to find a preparation, that which is known to be 

 there is not what is expected of the objective. The tubercle 

 bacillus and the gonococcus must be shown with sufficient ampli- 

 fication and distinctness to be readily diagnosticated by one not 

 an expert microscopist. For this purpose the 1-5 is not enough. 

 The ^ fills the demand, and the additional expense is slight. 



With such an equipment as I have described the necessary 

 work which every physician should do with the microscope can 

 be accomplished. It is also not absolutely necessary to expend 

 $75.00 or more in the purchase of such an equipment. Half that 

 sum will be sufficient. Were it not for the ban which the pro- 

 tective tarift' places upon importation, not more than from $20.00 

 to $40.00 would be necessary. While the tax upon education 

 has been removed as far as colleges are concerned, it is a fact to 

 be regretted that full and free opportunities for scientific education 

 and work are denied the individual. 



