170 



LOBB, ON A NEW MICROSCOPE. 



J, Achromatic object-glass, of which thirteen are supplied 

 by the makers, viz., two inch, one and a half inch, one inch, 

 two thirds of an inch, one half of an inch, four tenths of an 

 inch, three of one quarter of an inch of varied apertures, 

 one fifth of an inch, one eighth of an inch, one twelfth of an 

 inch, one sixteenth of an inch. 



Powell aud Lealand's New Compound Achromatic Microscope. 



K, Axis of the instrument firmly working on the supports 

 of the two front legs, so that the entire instrument is capable 

 of any inclination from vertical to horizontal, remaining 

 perfectly steady without clamping, in whatever position it 

 may be placed. 



