ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
G75 
thin and of diameter 6*5 mm., the lower part b is thicker and is 
soldered into the massive fastening c, which screws into the benzine 
reservoir. The lower part of the fastening is provided with a fine 
Fig. 97. 
passage d for the admission of air to the reservoir. In the interior of 
the tube is a wick extending from the top down into the reservoir. The 
upper end of the tube is provided with two extremely small holes x x, 
and is surrounded by a second short tube e, which carries two projecting 
