PKOCEEDINGS OF THE SOCIETY. 159 



habit of using different tinted glasses, and there could be no doubt 

 that a blue or red and perhaps even a violet glass placed on the 

 mirror or bull's-eye was of great use in many examinations. The 

 violet tint seemed to be of less use than the others, because this 

 colour was not so favourable to the eye. He had himself frequently 

 used green with opaque illumination and found it enabled him to 

 examine objects for a longer time than was possible by ordinary 

 yellow light. There was, however, this important difference between 

 the use of tinted light and polarized light, that it did not enable any 

 one to see hidden structures which polarized light so often displayed. 

 In corals, for instance, whilst coloured light was much better for their 

 examination than common yellow light, yet polarized light gave an 

 insight into their structural peculiarities — showing how the object 

 had been originally built up — in a way which mere variety of tint 

 was quite incapable of doing. He was glad to see this effort on the 

 part of Mr. Hardy to add to the beauty of some of their favourite 

 objects, especially as he felt that the attention given of late to high 

 powers had caused the aesthetics of the Microscope to become some- 

 what neglected. 



Mr. J. Mayall, junr., exhibited the stage by E. B. Tolles, of 

 Boston, U.S.A., which he thought would be of interest to the Fellows 

 after the description of it which appeared in the Journal, I. (1881) 

 p. 944. 



Mr. Beck exhibited an objective (without adjustment collar) of 

 l-6th in. focus, made specially for the binocular with very short 

 setting, so that the back lens would lie close to the prism. 



Mr. Ingpen remarked that the difficulty of obtaining any adjust- 

 ment for cover-glass was the great stumbling-block in the way of the 

 manufacture of such lenses. 



Mr. C. H. Stearn read his paper " On the Use of Incandescence 

 Lamps as Accessories to the Microscope" (see p. 29), the subject 

 being illustrated by the exhibition of the arrangements. 



The President said he felt sure the Society was very much obliged 

 to Mr. Stearn for having shown them this very excellent adaptation 

 of electric lighting to the Microscope. It showed them very plainly 

 what they would have to come to, and he hoped it pointed to a speedy 

 annihilation of all rock-oil abominations. The great convenience of 

 having a light so completely under command struck him as a great 

 point about it ; for in examining such objects as Echinoderms with a 

 2-in. objective, what was specially wanted was a light that could be 

 twisted and twirled round the object in the way shown by Mr. Stearn. 

 He sincerely hoped that the idea would be fully worked out, and that 

 it would be taken up by some of their great makers. No doubt those 

 who saw these little lamps exhibited at their last Conversazione would 

 agree with him in thinking that it was one of the most interesting 

 exhibitions ever brought before them. 



Mr. Stearn, in reply to questions from Mr. Beck and Mr. Crisp, 

 said that the accumulators which were under the table in the room 

 would work the lamps for several hours consecutively, but he was 



