350 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



time, as required ; they are operated from within the room. The size 

 of the mirror is 11 by 33 cm. 



Fig. 50. 



New Electrical Microscope Lamp.*— H. Poll's apparatus (fig. 60) 

 consists of a small electric incandescent lamp set in the interior of a 

 parabolic hollow mirror. It is of 3 to 7 volts and 4 to 5 candle-power, 

 and is of about the same size as the lamps used for cystoscopic purposes. 



Fig. 60. 



It works on the upper end of a pillar S, connected with the foot-plate F 

 by means of a hinge. The foot-plate has two binding screws for bring- 



* Zeitschr. f. wiss. Mikr., xviii.- (1902) pp. 413-7 (1 fig.). 



