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METHODS OF MICROSCOPICAL RESEARCH. 



The apparatus employed is simple. It consists of 

 a microscope of any ordinary construction, a power- 

 ful source of light, and a camera. The complete 

 apparatus perfected and manufactured by Messrs. 

 Swift & Son, Tottenham Court Road, from whom 

 price, description, and all particulars may be 

 obtained, is here illustrated. The mirror of the 



microscope is discarded except for special purposes, 

 because the loss by reflection is very serious. The 

 microscope is placed horizontally in a line with the 

 source of light, and with its tube inserted by a 

 light-tight joint into the front of the camera, which 

 is supported at such a height that its centre 

 coincides with the optic axis of the microscope. 

 The object is held on the vertical stage by means of 

 spring clips, and the light from the lamp is con- 

 densed on it by one or more condensing lenses. 

 There are two chief methods in use. In one the 

 eyepiece of the microscope is removed, and the 

 inverted image is received on the sensitive surface 

 where it is first formed. In the other the eyepiece 

 is retained in its place, and the image first formed 

 in its interior is formed again with additional 

 magnification by the aid of the eye-lens. By the 



