242 Records of the Geological Survey of India. [voL. xi. 
‘ arrastro,’ or else a rubbing apparatus should succeed it in the process of 
extraction. 
At tho time of my last visit, the Alpha works were at a standstill, several 
repairs being in course of operation, and the engine waiting for some fitting to 
tho boiler. Tho Manager, however, passed several samples of ordinary burnt 
tailings through the hand-process which clearly showed gold, only part of which 
was, however, taken up by even tho sodium-amalgam, and there was always colour 
of gold to the last of tho rubbing. 
The works of the Wynad Prospecting Company are planted a short distance 
down the slope of tho Carcoor cherrum, and a wire rope, some 400 feet long, is 
stretched from tho entrance of the galleries to tho works, along which tho baskets 
of vein-stuff are shot to a kiln, where the stone is bm-nt prior to being the more 
easily broken up and tipped into tho feed-box. Tho machinery consists of a 
Husband’s pneumatic stamper, driven by a turbine having a fall of about thiity 
feet of water, and capable of crushing half a ton in eight hours, tho working 
of these being remarkably easy and constant, requiring only such care as a well- 
trained native and his assistants can give. Prom the stamping box, the fine 
sandy slime passes over a series of two amalgamated copper tables, with a 
mercury trough at the end of each, whence it flows by a spout to the top of the 
hollow vertical shaft of a gidnding concentrator. The bottom of this shaft is 
screwed into a muUer (continuously hollow with the shaft), or inverted truncated 
cone, revolving inside of a fixed pan, the lip of which is level with the upper 
edge of the muller. After passing down tho shaft, the stuff is ground only in 
a very inefficient manner in tho pan and then agitated, but not rubbed inti¬ 
mately with the mercury, which lies at the lowest level, or out of reach of the 
grinding surfaces. This defect might certainly be obviated to some extent by 
filling up tho pan with a sufficient quantity of mercury; but this was not found 
practicable at these works; indeed, this apparatus was found to be of so little 
use either in grinding or concentration, that its employment was discontinued. 
To a certain extent, as its name implies, this machine is a concentrator; for the 
gold and the auriferous sulphides must, perforce, remain at the bottom of the 
pan longer than the rest of tho crushed material, which is caiaded away by the 
water; and in this way fi’cer scope is given for amalgamating, but effectual 
amalgamation, as far as Wynad gold is concerned, is not secured by such poor 
grinding and agitation. 
There is hero, in fact, very much the same defect as in the Alpha machinery; 
in both cases there is a machine which was expected to grind and amalgamate, 
but the grinding is only well done in tho Alpha pulveriser, while no effectual 
amalgamation takes place in cither apparatus. Prom the pan tho stuff passes 
over a further copper table into a transverse trough, with a fm-ther and last 
supply of mercury. A horizontal pipe, tho under-surface of which is perforated, 
runs along near tho bottom of this trough; water is turned on through the pipe 
with considerable force, and by its rush among tho materials at the bottom a 
violent agitation is caused, tho lighter sand is driven off, and a partial concen¬ 
tration is effected in contact with the mercury. Beyond this, a further series 
