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Dissecting Stands and Lens-holders. 



In order to facilitate the work of dissecting or teasing out small objects it 

 is most desirable to have the free use of both hands, combined with ease and 

 convenience in the use of a lens or a special dissecting combination. 



Our dissecting stands and lens-holders are designed to meet these require- 

 ments. The demands imposed on stands of this description are many; a suffi- 

 ciently wide margin in the movement of the holders, suitable illumination for 

 working with both transmitted and reflected light, convenient rests for the hands, 

 facilities for rapid changes of magnification, all these are only a few of the 

 principal points. In many instances it is also desirable to be enabled to make 

 drawings of the objects in various stages of preparation. 



Latterly we have made special endeavours so to construct our larger dissec- 

 ting stands as to meet all the above requirements and to afford the widest 

 possible margin in the admissible dimensions of objects and a very wide choice 

 of magnifications. 



A. Dissecting Stands. 



Stand PI. 

 Large Dissecting Stand as suggested by PAUL MAYER. 



A short column, which bears the square frame stage (10 X 10cm = 4X4in.) 

 and contains inside the rack and pinion adjustment of the objective carrier, rises 

 from a heavy horseshoe foot. A metal or glass plate, either solid or with a 

 central aperture, fits into the stage frame. Convenient folding hand-rests may 

 be attached at the sides of the stage. Fig. 38. 



With transmitted light the illumination is provided by plane and concave 

 mirror with universal motions, to which a piece of white paper may be attached 

 so as to produce diffuse illumination. By swinging a black or a white plate 

 round a pivot at the left forward corner of the stage either a dark or light 

 background may be slipped under the object at will. 



