288 PROCEEDINGS OF SOCIETIES. 



Drawings of 100 Foraminifera from the Dee Shepheard, T. 



Photographs and drawings illustrating the potato disease, and 



the growth of Agarics Sniilh, Worthington G . 



Lithographs of the microscopical structure of limestones, &c. . . Sorhy, H. C. 



Microscopical photographs of iron and steel „ 



Drawing made with the pigments extracted from human hair. „ ■ 



Series of large diagrams illustrating the structure of various 



rocks, meteorites, &c „ 



Drawings of microscopic objects West, Tuffen. 



Cryptogamic studies White, C. F. 



A "series of photographs of the Holy Land, &c S. and J. Beck. 



A series of objects exhibited by Mr. C. Stewart under the 



Society's microscopes. (See "'Animal Kingdom.") 

 The Martin Microscope, belonging to the Society, by Mr. Slack ; 



and a Reflecting Microscope on Amici's plan, by Cuth- 



bert.son ; also the spectacles and other apparatus used by 



Robert Brown in his botanical researches. 



Mr. F. H. Ward has kindly supplied the following description 

 of Mr. Bevington's microscope : — The microscope exhibited by Mr. 

 Bevington is a modified form of stand to be used with the binocular 

 arrangement of Mr, Stephenson. As this binocular is always used 

 in one position, the axis for inclination has been done away with, 

 and the instrument is supported by three legs -firmly attached to 

 the rectangular casting carrying the pinion of the coarse adjust- 

 ment. The fine adjustment has been obtained by chasing a fine 

 screw on the outside of the tube which receives the objectives, and 

 this is acted on by a milled collar of large diameter immediately 

 above them. The transverse arm, which usually contains the lever 

 for the fine adjustment, has been done away with, and instead of 

 it the upright piece with the rack of the coarse adjustment ter- 

 minates in a cradle, in which the centres of the bodies are balanced 

 and secured. This cradle revolves upon a cone, which in its turn 

 revolves upon the conical extremity of the upright, and as the 

 inside of the cone is turned excentric to the outside, by causing it 

 to revolve the objective is carried either backwards or forwards over 

 the stage, by revolving the cradle itself lateral movement of the 

 objective is obtained, and by these means the rotating stage may be 

 made perfectly concentric at any time, and then fixed by means of a 

 screw. In the binocular of Mr. Stephenson with the usual stand 

 oblique illumination cannot be obtained by moving the mirror to 

 either side of the instrument, as the light would then fall on the 

 prisms at difi"erent angles, and the fields of the eye-pieces would be 

 unequally illuminated. Mr. Bevington has obtained the requisite 

 obliquity by mounting the mirror on two brass rods which slide in 

 two tubes, one on either side of the ring that slides up and down the 

 main axis. The mirror has thus a range of about two inches in an 

 antero-posterior direction. For centering, Mr. Bevington substitutes 

 a cone terminating in a fine steel point for the objective, and secures 

 on the stage a piece of smoked glass, or chalked wood, then revolving 

 the stage a fine circle is described by this point, and after adjustment 

 a dot only, and he believes that this is a better arrangement than any 

 stage adjustment. There is also a lever which is made to embrace 



