PROCEEDINGS OF SOCIETIES. pA) 
melted glue and drop it on, and it fixed itself. I could prepare 
200 or 300 of them in the course of an evening, if necessary. If 
the object will bear a little warmth, we have only to heat the thin 
glass dise with which I cover it, put it on to the marine glue, and 
it cements itself. The whole thing is done without any difficulty. 
Mr. Wenuam.—lI beg to confirm what Mr. Shadbolt has said as 
to the use of paper being unsafe in damp places, and I also wish 
to call attention to a substance for making cells which is not 
generally known. In mounting Podura scales and other similar 
objects on thin glass, it is generally my practice to put the scales 
on the thin glass covers, and fix them with common heel-ball, 
drawing a hot iron round the edge of the thin glass, which cements 
it perfectly. 
Mr. Surrotx.—lI have another material to mention—pure tin, 
which is a soft metal, and can be cut with a knife or pair of © 
scissors, or punched. It is acted on by nothing but nitric or 
hydrochloric acid, and I have used it both for wet and dry objects. 
I have only obtained one thickness, but the metal will roll to any 
degree of thinness that may be necessary. 
Mr. Broox.—I have to mention one other material for the 
mounting of dry objects, for which, as far as I know, we are 
indebted to Dr. Golding Bird, who used it extensively for mount- 
ing specimens of Bryozoa, viz., small vulcanized India-rubber 
bands cemented down to the glass with a solution of India rub- 
ber, and then the slide was cemented on with the same material. 
They certainly entirely obviate the difficulty of any moisture 
getting in, as they are wholly impervious to wet. I have fre- 
quently made use of card discs myself, especially for mounting 
dry objects. I merely punched out small discs on the card, and 
then, with a small punch, punched out the centre so as to leave 
an annulus. That has been attached to the glass slide, and the 
thin glass laid over that with any kind of adhesive material; but 
I have always taken the precaution of varnishing round the whole 
of the slide, to prevent the growth of Conferva. With that pre- 
caution, I think a cardboard cell safe; but to protect the edge 
from the transmission of moisture by a layer of varnish only is 
wholly insufficient. 
The Rey. J. B. Reapz, F.R.S.—I may mention that Mr. Water- 
house, of Halifax, has used sheets of ebonite for the purpose of 
making cells; and he approves of it very highly, and speaks of 
it in the strongest terms of satisfaction. It is better than paper, 
certainly. 
Mr. Deane.—I think, where economy is an object, that there is 
a great advantage in the paper cell according to Mr. Smith’s plan. 
Ebonite cells and glass cells, and many others, are very expensive ; 
but if you can multiply paper cells and render them impervious 
to water in the way proposed by Mr. Smith, I think a very great 
service will be rendered to those who cannot furnish themselves 
with the more expensive descriptions of cells. I know Mr. 
Matthew Marshall used to mount-a great many objects in paper 
VOL. VI.—NEW SER. I 
