ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 



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horizontal axis formed by a hinge. The instrument is also rotatory 

 about a vertical axis. A rack-and-pinion adjusts the height and a 

 second rack-and-pinion the horizontal distance from the object. The 

 base-plate, on which the whole is mounted, can also be moved in two 

 horizontal directions mutually perpendicular. The movement from 

 front to rear is freehand and from left to right by the milled head T. 



Zeiss' Preparation Stand and Drawing Apparatus for Weak 

 Magnifications.* — This apparatus (rig. 97) not only satisfies all the 



Fig. 97. 



requirements of a preparation Microscope, but also serves for the draw- 

 in" of objects within increased limits of scale-selectiou. Two horizontal 

 arms are movable up and down on the strong brass pillar to the left. 

 The upper one bears at its extremity a perforation for receiving the 

 various holders for loups, spectacle-glasses, or an erecting Microscope. 

 The lower arm is a frame-shaped object-table for receiving a plate of 

 glass, metal, or wood. Illumination is obtained by transmitted light 



* Zeiss' Catalogue. 1902, No. 102, fig. 39, p. 7 J. 



