8o 



LABOR A TOR Y MICROSCOPES 



[CH. II 



FIG. 79. A. Queen & Co's Continental Microscope , No. II. B. Dust-prooj, 

 triple nose-piece. The difference between this and the ordinary form can be seen 

 by comparing with Fig. 36. This form of revolving nose-piece has been made for 

 many years by Winkel of Goettingen. 



