522 



SUMMARY OF CUKRENT RESEARCHES RELATING TO 



trough is in the form of a very elongated wedge. The lateral walls 

 are of metal which hold firmly between them the glasses which form 

 the oblique walls of the trough. This trough is fixed to a carrier 

 which can be moved up or down by a milled head. To the right near 

 the top of the screen is a square orifice through which the scale en- 

 » graved on the carrier can be seen. Behind the screen and the trough 

 is placed either a piece of ground glass, or a mirror with ground surface, 

 according as the examination is conducted by direct or reflected light. 



Fig, 105, 



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To the anterior face of the screen and in front of the two central 

 orifices a small apparatus can be applied, consisting of two total 

 double-refiection prisms, a very narrow diaphragm, and a lens. The 

 screen is attached to a vertical support, which obviates the necessity 

 of holding it in the hand, and it can be placed vertically or inclined 

 as desired. 



The accessories comprise (1) a guarded lancet, (2) a " melangeur " 

 (identical in construction with the " Melangeur Potain," see this 

 Journal, II. (1882) p. 561, fig. 107, but difierently graduated) for 

 making the solutions of blood, and (3) a small vessel to receive them 

 temporarily. 



