THE MICROSCOPE. 



Achromatic Object-glasses for the Microscope. 



* With the inch object-glass and the erecting-glasses, employing eye-pieces 

 Noa. 1 and 2, the magnifying power will range from 5 to 150. 



Among the accessories of the microscope due to Messrs. Smith, 

 and Beck, we must not omit to mention the microscope-table, 

 contrived to facilitate the observations of several persons directed 

 to the same object with the same microscope. Every one who 

 has used this instrument is aware how fatiguing it is to several 

 persons to succeed one another in observing with the same instru- 

 ment. They are obliged constantly to shift their position, and 

 consequently to make their observation standing. The micro- 

 scope-table, if it do not entirely remove this inconvenience, 

 greatly diminishes it. It is a circular table, firmly supported on a 

 pillar and claw, capable of being turned with a smooth motion 

 round its centre in its own plane. The observers sitting round 

 it, the microscope is moved successively to the position occupied 

 by each of them by merely turning the table. The best sort of 

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