FISH PHOTOGRAPHY AT HOME 189 



one. The difficulty, however, consists in the fact that 

 with the less elaborate apparatus a great deal of dodging 

 and manipulation is required, which necessitates assist- 

 ance. In order to facilitate photography of larval fishes, 

 on my return from Port Erin I constructed an appara- 

 tus by means of which it is possible single-handed 

 to take a photograph of living objects in a vertical 

 or horizontal position by daylight or by artificial 

 illumination. Further, the object can be photo- 

 graphed life-size (provided it is not more than five 

 inches in length), or any part of it up to a magnifica- 

 tion of 2,700. 



The aim I had in view when constructing this appar- 

 atus was that an expert biologist should be able to 

 put an object in a certain position upon the stage, 

 and that any ordinary photographer should be able 

 to photograph it at any given magnification by 

 transmitted or reflected light, night or day, without 

 touching it. 



I have illustrated the photographer at work with this 

 apparatus in the horizontal position taking a photograph 

 of a larval fish. The movements of the young fish in 

 the live cell are watched on the mirror of this reflex 

 micro-photographic camera. With the right hand the 

 object is kept in sharp focus all the time by turning a 

 screw which is connected with the microscope. As soon 

 as the larval fish is in the desired position, an exposure 

 is made by releasing the focal plane shutter with the 

 bulb in the left hand. 



