428 



Notes. 



ascertain many important facts with regard to their construction. But 

 to return to the fine adjustment : — it had a sprung nut K, fig. 108, and 

 also a sprung bearing for its lower portion at L, to prevent loss of time 

 in its action. The spring in the rack-slide of the lens-holder, fig. 106, 

 and also the spring P, fig. 108, which fits inside the round pillar, 

 and presses the triangular bar into one of the angles of its slide, will 

 be noticed. From the text we learn that this springing of the fine 

 adjustment was copied from a Microscope designed by C. Varley, 



Fig. 109. 



which is figured and described in the same volume of the Transactions 

 of the Society of Arts.* From the above account it will be seen that 

 this first Microscope of Andrew Eoss, or at least the first issued 

 under his own name, was an excellent and thoroughly practical con- 

 struction. 



In 1832 we find Andrew Eoss at 15 St. John's Square, Clerken- 

 well, and achromatic objectives .bearing his name with this address 

 upon them are still extant. In 1838 his address is 33 Eegent Street. 



* See figs. 72, 73, ante, p. 284. 



