406 MANIPULATION AND PRESERVATION OF THE MICROSCOPE 



rod, B, is screwed. The square rod carries a socket, C, with an arm, 

 D, to which the lamp is attached. 



On each side of the burner, and attached to the arm, D, is an 

 upright rod, G, to one of which the chimney is fixed, independent of 



FIG, 342. 



the reservoir of the lamp, thus enabling the observer to revolve the 

 burner and reservoir, and obtain either the edge or the flat side of 

 the flame without altering the position of the chimney. The 

 chimney, F, is made of thin brass, with two openings opposite to 

 each other, into which slide 3x1 glass slips of either white, blue, or 



