204 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



the points of the fork h and rotatory about an axis perpendicular to 

 those points. It will be readily seen that the arrangement permits of 

 adjustment in any position. The set of five twin objectives of the pre- 

 paration-Microscope can be used with the camera. 



Each of the slides introduced into the camera presents a real inverted 

 image of the object. 



The magnification varies from 1*6 to 7 diameters. This appears 



Fin. 24 



disproportionately small, but the stereoscopic magnification, in reality 

 supplying the ocular magnification, has to be reckoned in addition. 



Details of stops and light sources used are supplied ; and a coloured 

 plate illustrating some of the results obtained is appended. 



Ross' "No. 1 Model" Projection Lantern.— This is an exceedingly 

 small-bodied lantern fitted with lime-light jet (see fig. 25). It has 

 many novel points of construction, and is very portable, rigid, and 

 effective. 



At the exhibition of Messrs. Ross' new apparatus for lighting pur- 

 poses at the meeting of the Society on December 19th, 1900, this instru- 

 ment was also shown mounted on an extra and detachable base-board on 

 which may be placed any ordinary table Microscope having its optic axis 

 central with that of the lantern. The object of this combined apparatus 



