A GOOD LOW-PKICED MICKOSCOPE BY LEITZ 



243 



the best possible work into a spiral rack-and-pinion coarse adjust- 

 ment which works with great accuracy and smoothness, and has 

 dispensed with a fine adjustment. Its construction is neat, but it is 



FIG. 195. Powell and Lealand's portable microscope (1848). 



one of the most rigid of this class of microscope which we have seen 

 or used ; this instrument is sold for twenty-five shillings. But the 

 maker has adopted Mr. Xelson's plan, using a Steinheil magnifier to 

 be mounted as a sub-stage condenser, and if a simple iris diaphragm 



