LIME. 85 



haps some small pits, could be opened. Considerable quantities of cal- 

 careous boulders are washed down by some of the streams, but they 

 vary in composition from a rock like the above, containing 70 per cent, 

 or so of carbonate of lime, to a merely calcareous clunch, so that it 

 would be difficult to obtain a stone for cement purposes having a uni- 

 form composition. A rough approximation to the composition can be 

 gleaned from the fracture, which is rough and uneven in the calcareous 

 clunch ; both becomes finer as the proportion of lime increases, until in 

 a rock like that of which the analysis is given it is smooth and con- 

 choidal. 



One or two of the thickest beds of limestone have been marked 

 on the map ; but even these do not exceed a few feet. A 



The lime used in the Darjiling district is derived entirely from 

 calcareous tufa. In the Rumtek naddi, where a 

 quarry is at present worked by a Lepcha, I had 

 an opportunity of observing the way in which it is burned. 



The kilns, which are over 15 feet in internal diameter, consist 

 each of a circular wall about 10 feet high and % feet thick, built 

 of flattish stones from the bed of the adjacent stream. The interstices 

 on the inside are luted with clay, and at the bottom at opposite 

 sides are two orifices, about 3 feet high by 2 feet broad, for the ad- 

 mission of air, and from one of which the lime is withdrawn. There 

 is a rough shed close to the orifice, under which the lime is stored. 



The kiln is filled to within % feet of the top with logs of wood, 

 and then the tufa, in pieces averaging 2 to 4 inches long, is thrown 

 in and piled up into a low cone, the edge of which is on a level with 

 the top of the wall, and the apex some feet above it. After being 

 lighted, the kiln burns for about a week, and when tolerably cool, the 

 lime is extracted from below and slaked with water, in which state it 

 is sold. The uppermost part of the heap of tufa, which is exposed to 

 the air, and which merely acts as a blanket to keep that nearer the fire 

 hot, is scarcely burned at all, and is returned to the kiln at the next 



( 85 ) 



