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SUMMARY OF CURRENT RESEARCHES RELATING TO 



MICROSCOPY. 



A. Instruments, Accessories, &c* 

 (1) Stands. 



Exhibition Microscope.t — B. J. Howard, of the Bureau of Chemistry, 

 U.S.A. Department of Agriculture, gives a description of the Micro- 

 scope used in connection with the exhibit at the St. Louis Exposition. 



Fig. 102. 



The chief feature is a specially devised stage which carries three cog- 

 wheels so arranged that for each half revolution of the small pinion 

 the large one is driven forward ^ revolution. The large wheel carries 

 a circular plate-glass disk of 5 in. diameter, attached to it by means 



* This subdivision contains (1) Stands; (2) Eye-pieces and Objectives; (3) Illu- 

 minating and other Apparatus; (4) Photomicrography; (5) Microscopical Optics 

 and Manipulation : (<») Miscellaneous. 



t Journ. App. Micr., vi. (1903) p. 2727(1 fig.)- 



