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SUMMARY OF CURRENT RESEARCHES RELATING TO 



MICROSCOPY. 



A. Instruments, Accessories, &c* 

 (1) Stands.^ 



Bogue's Adjustable Dissecting Microscope.f — Fig. 45 shows the 

 form of dissecting Microscope invented by Mr. E. E. Bogue, of Oklahoma 

 Agricultural College, U.S.A. The intention is to provide an instrument 

 at which the dissector can work more comfortably than at dissecting 

 Microscopes of the ordinary low form. The instruments are of two 

 heights, to accommodate observers of different stature. Each Micro- 

 scope is provided with two racks and pinions ; one for adjusting the 



Fig. 45. 



lens, the other for raising and lowering the mirror stage and lens. In 

 the left-hand instrument the lens, when in focus, is 260 mm. from the 

 table, about the average height of compound Microscopes. In tbe right 

 hand one the lens is 360 mm. from the table. The lower rack-and-pinion 

 permits of all intermediate heights according to the needs of the 

 operator. The instrument weighs 69 oz., which is sufficient to give it 

 stability even when racked up to the highest point. 



Leitz' Demonstration Microscope. — This is seen in fig. 46. It is 

 adapted for low and medium power, and the square stage is fitted with 



5 1 * This subdivision contains (1) Stands; (2) Eye-pieces and Objectives; (3) Illu- 

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

 and Manipulation ; (6) Miscellaneous. 



t Journ. AppI.Micr., 1899. pp. 558-9 (1 fig.). 



