FOR MICROSCOPICAL LOW-POWER OBJECTS. 



355 



superfluous light. When working, however, in a brightly illumi- 

 nated room in daylight, a more effective screen will be found 

 necessary. We therefore have recourse to a box-like shade, 

 easily constructed of cardboard or thin wood, and illustrated in 

 Fig. 2, which shows the draw-tube of the microscope with the 

 mirror attached projecting through the opening at the back, and 

 the sketch-board in position. 



With regard to the illuminant, the light from a good paraffin 

 lamp will be found sufficient for a considerable amount of work 



x i . -. 



with low-power objectives. The advantage of a more brilliant 

 light, however, cannot be denied ; in fact, it is a necessity when 

 high-power work is contemplated. At the same time the successful 

 manipulation depends more upon the adjustment of the illuminant 

 than upon the actual amount of light available. 



Before concluding this paper I wish it to be understood that I 

 am not bringing this piece of apparatus forward as a new inven- 

 tion. It is, in fact, merely a practical application of the reflecting 

 property of the mirror. 



