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water, especially as it would not exhibit the disturbance of the surface of 

 the water by the needles. 



The President said that he generally used a black screen for the latter 

 purpose. There was one other point upon which he should like to have the 

 opinion of the Club, and that was upon the best way of illuminating things 

 whilst working by daylight. He could not get on very well with the con- 

 densing lens, and found it rather troublesome ; reflected light seemed to be 

 the best, and he had often wondered if a polished hollow cone would be a 

 good sort of thing to use. 



Dr. Matthews said that the idea had occurred to him of adapting some- 

 thing like the " speculum, uteri " to the purpose, which would resemble a 

 Wenham's illuminator inverted. He thought it would answer very well 

 with a lens inserted into the wide end; he was, in fact, on the point of 

 having one made, to try. 



Mr. Charles Stewart was sorry to say that he must differ somewhat from 

 their President as to the valne of the binocular microscope in dissecting, for 

 he had found it of the greatest use in the case of transparent objects, since 

 it enabled him to recognise the precise position of one object above or below 

 another, with a facility which he thought was of the greatest importance. 

 He also wished to bring before them a little matter which he thought might 

 be of interest, as it was in some degree connected with the subject which 

 had engaged their attention. In making minute insect dissections, he had 

 often f onnd the want of a perfectly structureless background upon which to 

 pin the object, and upon which it might be treated with spirit, and set aside 

 to work npon at leisure. He had tried various things, but at length Mr. 

 Field, of the Ozokerit Works, gave him a small quantity of black Ozokerit 

 (or black wax as they called it), and this seemed to answer admirably, for 

 it melted at a low temperature, remained soft enough to stick a pin into, 

 and was absolutely unacted upon by strong alcohol, or water, or by any 

 mixture of them. When required for use it was only necessary to put a few 

 knobs of it in a saucer, and when it was warmed it flattened out over the 

 bottom with as smooth a surface as could he desired. There were two sorts 

 of it, one being a little harder than the other — he had brought some speci- 

 mens of each with him to the meeting, both in the lump and run out in 

 small saucers ; the rims of these little saucers being ground off flat, a glass 

 cover could be laid over them, and the contents would be preserved from 

 dust, and, in a great measure, from evaporation also. One very great ad- 

 vantage about this stuff was, that there was no stain to come out of it; if 

 gutta percha was used, the spirit extracted a kind of gummy product from 

 it, a stain came out of it, and it very soon became brittle, whilst even the 

 best cork contained numerous small cells, which got out after a time, and 

 seemed to have a peculiar proclivity for attaching themselves to the most 

 delicate nerves and filaments. The new substance seemed to him to fill a 

 want, and it was equally useful for large dissections, as it could be made to 

 line a trough with very little trouble. 



The President said it struck him that the idea of using this material was 

 a very important suggestion, and he could see at once that, in comparison 



