220 W. K. BRIDGMAN ON A NEW REFLECTING ILLUMINATOR. 



Fig. 3. Vertical section of reflector, with its directing tailpiece (P) for 

 altering its angle, and its movable shutter or diaphragm (D) for 

 regulating the quantity of light and restricting the admitted 

 portion to a vertical section through the diameter of the cone of 

 rays. 



„ 4. Inside view of arrangement for carrying the reflector and its dia- 

 phragm. (F) and (G), a frame of brass attached to the instrument, 

 and upon which Fig. 6 is held by the bar (I) and spring (H), and 

 adjustable by the finger and thumb applied to the tube (J). 



„ 5. Outside view of Fig. 6 in position upon the frame and set fast upon 

 (G) by the screw (K). 



,, 6. The speculum carrier, (S), speculum, (D), diaphragm or shutter 

 attached to the bent arm, (E), and adjusted by the screw, (X) ; 

 (M), milled head to the screw and bent lever acting upon the 

 reflector, (S). 



