103 
recently attracted so much attention, and I believe they will 
he found throughout the debris. For all these reasons, there- 
fore, I submit that there is no ground for the theory of 
glacial action as put forth by these gentlemen, but on the 
contrary that the filling of the Victoria Cave was the work 
of long ages, by the action of running water, and that there 
is no reason to suppose that the remains found in it are 
older than the glacial epoch. 
The President exhibited a syphon barometer, the pecu- 
liarity of which consisted in the introduction of a small 
quantity of sulphuric acid over the ends of the mercurial 
column. 
Mr. Spence, F.C.S., communicated to the Society the 
result of an experiment in heating a diamond, which will 
considerably modify the general impression as to that gem 
being combustible only at an extremely high heat. 
A friend of his had brought over a number of diamonds 
from the African mines. Some of these were what is called 
“ off colour,” not being purely white, and he put one of these 
into Mr. Spence’s hands to try some experiments for dis- 
placing the colour if practicable. 
This diamond, the size of a small pea, was immersed in 
fire-clay in a small crucible, the clay being mixed with a 
little carbonate of soda and hydrate of lime, the crucible was 
then placed in a muffle, and for three days and nights 
exposed to a heat, which, at no time, was beyond a low 
cherry red. After cooling, the crucible was broken, and the 
lump of hardened fire-clay was carefully broken up to 
extract the diamond ; after two or three fractures of the 
lump an impression or hole in the indurated clay was 
