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A SIMPLE METHOD OF TAKING STEREO-PHOTO- 

 MICROGRAPHS AND MOUNTING THE PRINTS 

 WITHOUT CUTTING. 



By H. Taverner, F.R.M.S. 



{Bead April 20th, 1906.) 



Plates 22—24. 



In November, 1903, I had the pleasure of exhibiting before the 

 Royal Microscopical Society two photographs of the hairs on 

 the leg of a water-mite, which I had taken through the right 

 and left tubes of a binocular microscope, in order to demonstrate 

 that the two images were not identical. I did not bring the 

 matter forward as a new discovery, but simply because the 

 object was particularly suited to demonstrate the fact, which 

 I knew was disputed by some microscopists. The photographs 

 in question were too small to be viewed stereoscopically, and 

 I therefore exhibited, under a stereoscope at the same time, 

 two prints of the same subject, taken by a different method, 

 with a magnification of over 200 diameters, which proved that 

 the two dissimilar images combined to form a stereoscopic 

 picture. The method then adopted for the production of the 

 photographs was to cover the front of the objective with a 

 cap (Fig. 1, «), by means of which exactly one-half of the front 

 of the lens w T as cut off. The rotation of this cap through 180° 

 allowed separate pictures to be taken by the right and left 

 halves of the lens. 



I did not pursue the matter farther at the time, but shortly 

 before Christmas last I wanted a similar photograph for a friend, 

 and it then occurred to me that the axial rays of light were 

 detrimental to the formation of a stereoscopic image, and that 

 if I could stop them out I should obtain better results stereo- 



Journ. Q. M. C, Series II. — No. oS. 21 



