380 PROCEEDINGS OF SOCIETIES. KSLlEfi?rS 
secure. It is equally available for objects requiring to be mounted in 
deep cells, and there is no danger of leakage, as is the case with all 
fluids ; it can be readily removed from slide and cover with hot water, 
if necessary. The refractive powers of the glycerine are sufficient to 
render all inert structures transparent, whilst even the delicate lines 
upon the scales of a mosquito's wing are as distinctly visible as though 
mounted dry. 
" Finally, I desire, in bringing the subject before the Department, 
and mentioning my experience with its use, to interest other members 
in the matter, to induce them to try it, and to bring together from 
time to time the results we may severally arrive at. For I conceive 
it to be almost as important to arrive at a means of preserving per- 
manently objects suitably prepared for scientific observations, as to be 
able to prepare them for such observation without reference to their 
preservation. Since we can only hope to arrive at accurate conclu- 
sions by repeated study, not by one, but many observers, this can only 
be done by having the object suitably prepared and permanently 
preserved. 
" The formula for making glycerine jelly is as follows : — 
" Take one package of Cox's gelatine, wash repeatedly in cold water, 
then place in a vessel and add sufficiently cold water to cover it. 
Allow it to soak an hour or two, pour off superfluous water, add one 
pint of boiling water, place vessel on fire and boil for ten or fifteen 
minutes. Eemove from fire, and when cool, but still fluid, add the 
white of an egg, well beaten, replace on the fire and boil until the 
albumen of the egg coagulates. Strain while hot through flannel, and 
add an equal portion by measurement of Bower's pure glycerine, and 
fifty drops of carbolic acid in solution ; boil again for ten or fifteen 
minutes, and again strain through flannel, place in water-bath, and 
evaporate to about one-half, then filter into two oz. broad-mouth vials. 
(Cotton is the best filtering medium.) 
" To use the jelly in mounting objects : — Place the stock bottle in a 
small jar of boiling water ; when it becomes fluid, a sufficient quantity 
must be removed to the slide (previously warmed) with a glass rod ; 
the object (previously soaked for some hours in equal parts of 
glycerine and distilled water with a few drops of alcohol) is to be 
placed in the drop of fluid jelly, a cover applied and slight weight 
placed upon it to exclude superfluous jelly. When cold, clean off the 
slide with a knife and wash in cold water ; finish with a ring of gold 
size or shellac varnish. 
" Dr. Carpenter cautions against use of Glycerin with objects of a 
calcareous nature, as it is a solvent of carbonate of lime." 
Mr. Chas. Bullock remarked that it is important to give the 
gelatine frequent washings previous to use, to remove traces of sul- 
phuric acid, which invariably remain from the process employed in its 
preparation. 
Mitchell W. McAllister, S. Fisher Corlies, and Dr. J. G. Eichard- 
son, were this evening chosen members of the Department. 
Prof. O. Holmes, of Boston, was chosen a corresponding 
member. 
