12 



" Medical Examiner." Weekly ... ... „ the Editor. 



"Analyst" ... ... ... ... ... „ „ 



" American Naturalist " ... ... ... in exchange. 



" Report of the Bristol Naturalists' Society '' from the Society. 

 Photographs of Mr. H. G. Glasspoole and Mr. 



F. Grayling. 



Specimens of Drosera rotundifoUa, for dis-") -., p . , 



tribution ... ... ... ... * 



Mr. Ingpen described a method of oblique illumination exhibited in the 

 room by Dr. Dickson, of Glasgow. An ordinary bull's-eye condenser was 

 placed with its convex side uppermost and its flat side nearly horizontal, 

 and reflected the light in the same manner as an Amici prism, and with very 

 good effect. It was of great use to know that an appliance like a bull's- 

 e)e, which was almost always at hand, could be turned to such good 

 account. 



Mr. Ingpen then gave a description of the various forms of camera 

 lucida which had been devised for landscape drawing, and for use with the 

 microscope. First explaining the principles upon which the camera lucida 

 was constructed, he proceeded to describe various forms devifed by Dr 

 Wollaston, Amici, Soemmering, Beale, Nachet, Doyere, Nobert, Chevalier, 

 and others. Particular reference was made to Goring and Pritchard's rnico- 

 graphia (1837, p. 221, " Quekett," on the Microscope, 3rd ed., 1855, pp. 

 167, 253 ; Carpenter on the Microscope, 5th ed., 1875, p. 127. et. seq. ; 

 " Quarterly Journal of Microscopical Science," vol. viii., p, 156 j and atten- 

 tion was drawn to the utility of the camera lucida, as a check upon " fancy 

 drawing," as offering facilities for making rapid and faithful sketches of 

 living objects, and of cultivating habits of accurate observation. Nearly 

 all the forms described were exhibited in the room. 



Dr. Cooke said that he had been in the habit of using Nachet's camera 

 lucida almost daily for some years, and found it of the greatest advantage. 

 Any difficulty in seeing the pencil could easily be overcome by using a 

 second lamp, as generally the object was too bright, and the pencil in con- 

 sequence indistinct. He always used a microscope in a fixed position, with 

 the camera attached and ready for use at a moment's notice ; and some care- 

 ful measurements having been made once for all, the sizes of objects ex- 

 amined, and the extent to which they were magnified, could also be recorded 

 with each drawing. 

 ' In answer to a question, Mr. Ingpen said that the difficulty found by 

 many persons in \ising the Wollaston camera was caused by their keeping 

 the eye too far over the prism. 



Mr. Curties advocated the use of squared paper, as being in some re- 

 spects more convenient than the camera, and said that Mr. Suffolk had 

 expressed a similar opinion. 



The thanks of the Meeting were voted to Dr. Dickson and Mr. Ingpen 

 for their communications. 



The Chairman announced the engagements for the ensuing month, and 



