42 Reports and Proceedings— 
resorted drift is exactly similar to the material which had accumu- 
lated against the old fence, the very existence of which had been 
denied. The swallow-hole action to which he referred the pheno- 
mena was proved by the opened fissures and vertical cylindrical 
holes in the limestone and by the occurrence of a land-shell (Zonites 
cellarius). He held that there had been a breakdown of the roof 
and wall of the cave under the drift, and that angular masses of 
limestone, due to this cause, were found all along in front of the 
upper opening to the cave. No bones were found outside that 
barrier, there being no bones in the shell-bed and no shells in the 
bone-bed except the land-shell washed down through a fissure. 
Instead, therefore, of the difficult task of proving that there were 
in the district many well-known processes connected with subter- 
ranean denudations, which might explain the superposition of the 
marine drift upon the bone-earth, each of which had played a part 
in producing the results observed, he maintained that we had now 
the clearest evidence as to the exact manner in which it was all 
brought about, namely, that the marine drift was deposited before 
the occupation of the cave by the animals whose remains have been 
found in it; that at the time of the occupation of the cave the 
upper opening now seen did not exist, but the animals got in by 
the other entrance; that against the wall of the cave where it 
approached most nearly to the face of the cliff, the drift lay thick 
as we now see it; that by swallow-hole action the cave was first 
partially filled, and then the thinnest portion of its wall gave way 
gradually, burying the bone-earth below it, and letting down some 
of the drift above it, so that some of it now looks as if it might 
have been laid down by the sea upon preexisting cave-deposits. 
II.—December 7, 1887.—Prof. J. W. Judd, F.R.S., President, in 
the chair.—The following communications were read :— 
1. “A Letter from H.M. Secretary of State for the Colonies, en- 
closing an account of recent Discoveries of Gold in the Transvaal.” 
The deposits in which gold has been found, locally known as 
“ banket,” consist of a quartz-conglomerate forming so-called * reefs,” 
which traverse the veldt paralled to, but at a short distance from 
the rocky ridge of Witwatersrand. These masses always dip to the 
south, but at angles varying from 50° up to 90°. The “reefs” are 
believed to have been discovered by Mr. Struben, an English gentle- 
man long resident in the country. The “main reef” has been traced 
for twenty-five or thirty miles, and varies in breadth from 5 feet 
6 inches to 15 feet; parallel and branching “reefs” of smaller 
dimensions have also been found. The yield of gold is said to be 
very variable in different portions of the “reef,” different samples 
with from 8 0z. to 4.0z. per ton occurring in close proximity. So 
far as observation has gone (and the deepest workings have only 
reached a depth of from 70 to 150 feet), the yield of gold has gene- 
rally increased as the reefs are followed downwards. 
2. “On the Age of the Altered Limestone of Strath, Skye.” By 
Dr. Archibald Geikie, F.R.S., V.P.G.S. 
