526 



The Mines of Klietree in Bajpootana. 



[No. 5, 



are employed in breaking it up into small pieces. The broken shale 

 mixed with the crust from the refuse heap, (hereafter alluded to,) is 

 then put into gurrahs till they are half full. The gurrahs previously 

 arranged along the edges of the heap are then filled with water. The 

 whole is turned and mixed three or four times a day by one of the men 

 with a bit of broken gurrah in his hand, so as to expose every 

 part. 



At the end of 24 hours, the water, which now holds a considerable 

 quantity of the sulphates in solution, is poured off into other gurrahs, 

 holding a fresh portion of shale, and surface refuse, whilst fresh water 

 is added to the first shale. The operation is repeated a third time 

 with the shale, after which, the latter having parted with a considerable 

 quantity of its sulphates, though not by any means with the whole, (as 

 the shale was at first only coarsely broken and not pounded,) is 

 thrown along the slope of the refuse heap, which is purposely kept 

 smooth and hard. 



The refuse heaps Plates VI, VII, are formed as truncated cones and 

 #re very regularly and evenly kept ; so much so, that they appear as if 

 prepared and kept smooth by a spade. They rise in successive layers to 

 & considerable height, each being less than that below it, by the 

 breadth of terrace left at its base ; this terrace is bordered by a low 

 ridge for the gurrahs containing the shale, and which give to the 

 whole so peculiar an appearance. The ridge also serves to retain 

 any water that may be spilt on the terrace, and any rain water, which 

 sinking into the heap, carries portions of the sulphates to the surface 

 slopes, where efflorescence takes place as the heap dries. It is this 

 surface shale which is mixed with the 

 fresh shale from the mines in equal 

 quantities, to form the material with 

 which the gurrahs are charged. The 

 section of a pile would be something 

 like the accompanying figure. Year 

 after year the heap increases by the 

 deposition of half exhausted shale, and many of the existing heaps are 

 formed of the refuse materal accumulated by many generations. 



It has been already said that each charge of shale is exposed to 

 three changes of water. The water on the other hand is changed in 

 the gurrahs, till it has taken up, the sulphates from seven different 



