238 
Records of the Geological Suneg of India. 
[vOL. XI. 
positions, one showing a westerly dip, I am the more inclined to view the case 
as one of displacement, in preference to one of sudden absence of the reef altoge¬ 
ther over any appreciable area. 
A further source of disappointment in the present system of mining may also, 
I think, lie in a possible mechanical distribution of some of the gold irregularly 
throughout the reefs by the mere percolation of water in this zone of varied 
decompositions; and that thus the gold may be found not only more fitfully dis¬ 
tributed than is at times usual with the precious metal, but even to some extent 
washed out of the reef. Although there is no certain evidence that gold may be 
thus distributed through reefs, the possibility of such a mechanical process seems 
quite conceivable when the conditions of some of the reefs and their gold are 
considered in conjunction with the effects of such an exceptionally moist climate 
as that of Wjmad, where the movement of water underground must bo propor¬ 
tional to that on the surface. The quartz of many reefs, as far as is disclosed by 
the old excavations, and later by recent workings, particularly in the Skull reef, 
is much fis.sured and very often minutely, and even in part continuously, cavernous, 
or, again, quite crumbling and rotten from having been so largely charged with 
sulphides, while the gold left is generally in a minute state of division; and 
throughout this style of vein-stone there is tolerably free percolation of water in 
quite sufficient force to cany off minute gold. In nearly all the old excavations 
which I examined, and some of these are at the base of the Dayvallah ridges, 
water was dripping freely from the exposed surfaces of quartz. Nearly all the 
long outcrops of the reefs are really just catch-surfaces for water; while the reefs 
themselves and their clayey selvages must be, in many instances, only so many 
channels for the flow of water through the zone of decomposed rock. Among 
other modes of occurrence, the gold is found in empty cavities, once also occupied 
in part by sulphides, which have left their impressions on the quartz ; or it is 
intimately associated with sulphides in partially filled cavities; or, again, it and the 
sulphides fill up such hollows. In the first and second cases, more or less sul¬ 
phides have been removed, more generally by solution, but still to some extent 
mechanically; most likely as fine ochre. The gold associated with these was 
then either left behind, as is often the case, or it might, if minute enough, have 
been carried along with the solutions, or subsequently, by the ever-recurring 
passage of water, to be caught again in favourable hollows, or collected in and 
against the clayey casing,^ or gravitated to the plane of constant saturation, or 
finally, carried out altogether by springs in the Ghats.® 
With the possibilily, then, of such a secondary distribution of part of the gold, 
and an extreme probability of encountering more or less disturbance of the reefs, 
in the ground within the reach of atmospheric influences, it becomes an import¬ 
ant question how far those influences may extend beneath the surface, or, in 
' Tlie frequent richness of casing and wall-rock, though generally accounted for by chemical 
action, may be in part also due to this, as it were, secondary process of distribution; for there is 
free gold here as well as in the veins. 
^ For some interesting remarks upon the possible removal of gold by solution, see Raymond’s 
Mining Statistics West of the Rocky Mountains (1871), p. 508. 
