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firm foot. There is a small mirror and stage. The instrument is provided 
with the universal screw, so that the objectives of one’s usual microscope may 
he attached to it. 
THE TRAVELLING MICROSCOPE. 
An ingenious Pond-stick , which will be found very useful by those engaged 
in collecting infusoria, &c., from ponds, has been constructed by Messrs. Baker. 
In appearance it resembles an ordinary walking-stick. When the ferrule is 
unscrewed a second stick may be drawn out from within the first, thus 
doubling the length. To the end of this is attached a brass ring, and into this 
can be screwed a dipping bottle. These bottles may be had of various sizes, 
and as the glass neck is worked into a screw they can readily be attached to 
the ring. 
The MicroscopisT s Air-pump . — Most of the air-pumps in use by micro- 
scopists are large, inconvenient, and expensive. Mr. Baker has, however, con- 
structed one which is especially intended for the preparation of microscopic 
objects, and which appears likely to prove useful. Beneath a solid table is 
fixed the pump in the form of a brass syringe. This communicates by an 
aperture with a smooth metallic plate fixed on the table. When required 
for use the object is laid on this plate and is covered with an oblong glass 
box whose edges are ground and greased (being thus rendered air-tight). 
The syringe being now worked, the air is rapidly removed. The plan was 
devised by Mr. W. Moginie. 
