Achromatic Object-Glasses for the Microscope. 



With the § inch object-glass and the erecting glasses, employing eye-pieces Nos. 1 and 2, 

 the magnifying power will range from 5 to 150. 



APPARATUS 



which applies to the cylindrical fitting under the stage of 



No. 1 or No. 2 Microscope. 



£ s. d. 



Achromatic Condenser on an improved constructiou of two 

 powers, and revolving diaphragm, to give various 

 illuminating pencils from 80° to 25°, also stops for 

 the central rays, complete with adjustments 5 



Achromatic Condenser without diaphragm, apei-tiu-es 60° and 



20°, brass work with adjustments 2 10 



Achromatic Condenser, Brasswork of, with adjustments 10 



Wenham's Parabolic Reflector, giving a dark field with an 

 object-glass of 100° of aperture, with adjusting stop 

 and fittings 1 15 



Amici's Prism for oblique light, mounted on an improved 

 plan, with the reflecting surface uncovered for the 

 convenience of wiping 2 2 



