Note on a Travelling and Sea-side Microscope. 499 



Baker, the instrument had tubular legs constructed to hold pipettes, 

 and the body was of sufficient diameter to take large-sized eye- 

 pieces. 



The modified form figured was constructed by Messrs. J. Swift 

 and Son, and was catalogued by that firm until recently. The body 

 and draw-tube, together with an eye-piece adapter, extend to 8^ in. 

 and close to 4^ in. The spread of the folding tripod foot is 5^ in. 

 The stage turns on a well-made pivot for convenience in packing ; 

 plane and concave mirrors are furnished ; while the whole instrument, 

 which is remarkably well finished, and weighs only 1 lb. '2 oz., packs 

 into a leather-covered box measuring 6^ by 2f by 2^ in. A really 

 good micrometer screw fine adjustment is provided, working on a 

 triangular bar ; this moves the body steadily and smoothly without 

 lateral shake even when high-power objectives are employed. 



The writer has had a small achromatic condenser added of N.A. 

 1 ' 0, furnished with an iris diaphragm and a fitting to carry either 

 central stops, slots, or a green -glass light-modifier. The top lens of 

 the condenser system is removable for low-power work. Thus fitted 

 the instrument is admirably adapted for all purposes to which the 

 more elaborate descriptions of travelling Microscopes are usually put, 

 and will allow of the employment of even oil-immersion objectives. 



An additional tripod foot is sometimes provided, in order that the 

 Microscope may be used in an upright position when necessary. 



