652 SUMMARY OF CURRENT RESEARCHES RELATING TO 



A small flange F fitted over the eye end of the Microscope is required, 



to form a table upon which to rest the camera. 



In order to overcome the tendency of the body to move downwards 



during a prolonged exposure, a block of metal G, which slides up and 



down the coarse adjustment, and can be clamped in any position, is 



supplied. 



A yellow screen H (fig. 158), fixed on a stand with universal motion, 



should be employed between the Microscope mirror and the light in 



connection with isochromatic plates 

 for all powers higher than a § in., 

 otherwise the focus cannot be relied 

 on with certainty. 



With this apparatus photographs 

 can be made If in. in diameter, 

 having such fine detail that they 

 will bear enlargement to any reason- 

 able extent. One of the chief ad- 

 Fig. 153. vantages of this extremely simple 



method of photomicrography is 



that the optical performance of the Microscope is exactly the same as 



when it is used for visual observation. The apparatus is made by the 



firm of R. and J. Beck. 



A Perfectly Steady Stand for Photomicrography.* — J. Ries has 

 sought to attain (1) the advantages of the Zeiss large photomicrographic 

 camera by a less costly construction ; and (2) to contrive an apparatus 

 which shall be useful for all kinds of photography. The Zeiss model 

 requires two tables, one for the Microscope and one for the camera, so 

 that the unavoidable slight disturbances of the camera due to manipu- 

 lation shall not extend to the Microscope. The cost and the dimensions 

 of so much apparatus practically limit its use to institutions. The 

 author seeks to make his Microscope perfectly steady and at the same 

 time independent of the camera by mounting it securely on a heavy 

 triangular base. This base fits freely but accurately within a triangular 

 frame to which the optical bench with camera is attached. Thus the 

 size of the whole is kept within moderate limits. The bellows are 

 45 cm. long, and are controlled by a double rod-rack gear. The front 

 and back frames are secured on two platforms clamped to the optical 

 bench and governed by the rod-gear. The camera can be easily set up 

 or removed. It may be used without the Microscope, and thus serve for 

 all photographic purposes. The author illustrates his method by suitable 

 diagrams. 



■6' 



H., Dr. — TJnsichtbares Lioht im Dienste der Mikroskopie. 



[Mainly deals with Dr. Kohler's photomicrography with ultra-violet rays.] 



Central-Zeit. f. Opt. u. Mech., xxvi. (1905) p. 34. 



Simon et Spillmann, L. — Application de la photographie a la numeration des 

 elements figures du sang. Comptes Eendus, lvii. (1904) pp. 659-60. 



* Zeitschr. wiss. Mikrosk., xxi. (1904) pp. 475-8 (5 figs.). 



