Do the Mining Operations affect the Climate of Kimberley? 7 
DO THE MINING OPERATIONS AFFECT THE CLIMATE 
OF KIMBERLEY ? 
By J. R. Sutton. 
(Read October 27, 1898.) 
In essentials diamond-mining differs little from any other enterprise 
whose object is to obtain possession of minerals lying at any depth 
beneath the surface of the earth. Shafts have to be sunk, and 
tunnels driven, and the diamond-bearing rock (‘‘ Kimberlite’’ or 
‘‘blue-ground’”’) has to be excavated and hauled to the surface for 
treatment before its wealth can be proved, in much the same way as 
though the quest were gold or iron. But diamond-mining differs 
from most other extensive mining operations in this: that Kimberlite 
being for the most part easily pulverable by ordinary atmospheric 
influences continued long enough, is more advantageously and 
cheaply treated by spreading it, as soon as it leaves the mine, 
over the ground, where sun and rain can act freely upon it and 
disintegrate it, than it would be by crushing, or by any other process 
having the same objects. The depositing sites for blue-ground fresh 
from the mines are known as Floors. The floors belonging to the 
De Beers and Kimberley Mines extend, practically without interrup- 
tion, some four miles east and west, and from one to two miles north 
and south; and in order that they shall be as convenient as possible 
they are cleared of every trace of vegetation—trees, bushes, and 
grass all being sacrificed. The blue-ground is spread upon the 
floors to an average depth of about 10 inches, and remains there 
for a period which may run into many months until it is sufficiently 
disintegrated to be ready for washing and sorting. It is seldom that 
any floor is clear of blue-ground for many consecutive days; for the 
tipping of fresh material follows closely upon the removal of the old. 
Thus the floors-area, so far as vegetation is concerned, may be 
regarded as a small desert of blue-earth and rock, with here and 
there large mounds of the waste material from which the diamonds 
have been extracted. Kimberley extends along the southern boundary 
of this desert, and the village of Kenilworth (Griqualand West) 
touches it on its northern edge. Surrounding the whole is the 
virgin veldt of the country, consisting of thorn-bushes at intervals, 
