ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 



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provements, such as a clamp to the tubular pillar, a turret mechanical 

 stage, and a curved arm to carry the body. The date to be assigned to 

 it must therefore be between 1884 and 1838. 



Fig. 7. 



The massive, flat tripod foot, of peculiar shape, is surmounted by a 

 tubular pillar holding an extension-rod, which can be clamped by a 

 screw-ring ; the rod is surmounted by a compass joint, to which the 



