PART 3 .] 
ITaclid.: Salt in Kajpulana. 
199 
of 100 feet in height above the level of the lake; thus the northern shore of the 
lake near Guclha is 1,184 feet above sea level, whilst An, about 1 mile from 
the southern shore, is 1,262 feet, Singla, 4 miles from the southern shore, 
1,292 feet, and Duri, about 6 miles east of the lake, 1,363 feet above sea level. 
These ridges of sand arc formed by the west wind bringing the sand through 
the gaps in the ridges of quartzite forming the range. The lake is merely a hollow 
in the sand, lower than the surrounding country, from the fact of its lying under 
the lee of one of the.se high ridges and so protected from the blown sand. 
The drainage area of the lake is about 2,200 square miles. 
Of the two princi25al streams that flow into the lake, one talces its rise about fiO 
miles to the north-ea.st, and the other near Ajmore about 40 miles to tho south. 
As the lake becomes dry, a deposit of black mud is left at tho bottom, which, 
when diy, contains numerous small crystals of salt. Mr. Adams, tho Assistant 
Commissioner of Inland Customs at Sambhar, gives the following section of a j)it 
sunk 10 feet dee}) in the bottom of the lake near the low water level opposite 
JajDOg. “ After penetrating through a layer of about one and a half feet in 
thickness of the dark gieyish sand which, when covered with -water, becomes the 
black mud of the lake, about half a foot of quicksand with brine was met 
with. Below this a black micaceous sand occurred, which was much decomposed 
on the surface, but which became gradually harder downwards. A very similar 
stratum of micaceous schists' occurs in wells about 4 miles to the south¬ 
east of Ja 2 )og.” (Inland Customs Rejsort, 1870-71, p. 113). 
Outcrojis of these schists occur on the shores of the lake near Japog and 
several other places. They belong to the Arvali series of rocks, of which mention 
will presently be made. 
Calcareous dej^osits of considerable thickness are of frequent occurrence I’ound 
the shores of the lake. They are well developed near Sambhar and Nan-^va. 
Those dejiosits are apparently formed by the infiltration of water into the blown 
sand forming the banks of the lake. Upwards of 20 feet of this concretionary 
limestone is exjjosed in a well sunk on the southeni shore of tho lake near 
Kotarsina. 
Tho followdng statements relating to the specific gra'('ity of the lake water is 
taken from Mr. Adams’ report for 1870-71 {1. c. p. 115) “ The specific gravity 
of the lake w'ater during the past rains never -was less than that of sea -water, 
the siiecific gravity of sea -water being given as 1'03, while tho lake wuter on 
30th July gave 1‘03. In August about 5 inches of rain fell, and as the evajjo- 
ration, owing to the humid state of the atmosphere, -was alight, tho specific gravity 
was the same as that at the end of July. During September the specific gravity 
kept at 1’04 ; in October it increased from 105 to 1'07; in November it varied 
from 1-08 to TIO; in December, owing to some slight showers of rain, it was 
reduced to 1‘095; in January it increased from I'll to 1-14; in February it 
increased from I'lo to 1-20, and at this specific gravity salt began to deposit. 
No difference of gi-avity was at any time observed in tho brine taken from the 
.surface and that taken from the deepest part of the lake. 
> It is to 1)0 presumtd tLat the ‘ sand ’ of the preceding seiitciico is decomposed schist. 
