54 



THE AMERICAN MONTHLY 



[Feb., 



suggest themselves more particularly to the aiiatomiist 

 as indis])ensible, have been suppressed, sucli as tlie outer 

 tube for swinging the body to one side, and the numer- 

 ous sockets for stage forceps; and the rotating diaphragm 

 has been replaced by a tube moving vertically through 

 the opening in the stage, by the aid of a lever at the side, 

 so as to take from above the achromatic condenser of 

 Dujardin patented at the same tim«, or a set of cylindri- 

 cal diaphragms, a feature of which Strauss-Durckheim 

 expressly objected as necessitating the disturbance of 



the preparation on the stage. A rack-and-pinion coarse- 

 adjustment has been added, and the milled head of the 

 line-adjustment removed to the top of the pillar. 



This instrument came into great favor, much aided by 

 its cheapness, and the goodness of the objectives ; and 

 and was exhibited at the sitting . of the Academie des 

 Sciences on February 13, 1837. 



On the occasion of Nachet exhibiting at the Academie 

 des Sciences an api)aratus for oblique illumination by 

 means of a prism on June 14, 1847, ten years later, 

 Oberhaeuser, now in the business by hin^self, announc<'<\ 



