PART 3.] 
ILtciet: Saif In Hajpul an a. 
201 
Analysis of day from Lahe-hed .—“ Tlic sample was taken from tlie Lake-bed, 
some feet under the surface, when the reservoir was being excavated, in walled 
enclosure No. 2, in December 1869. 
Water ... ... ... ... ,,, 38'9 
Silica ... ... ... ... ,,, 25'0 
Oxide of alumina, iron, iScc. ... ... ... 8'6 
Carbonate of lime ... ... ... ... 8'1 
,, of magnesia ... ... ... 3-4 
Cliloride of sodium ... .. ... ... 13-1 
Sulphate of soda ... ... ... ... 2’8 
Carboimte of soda ... ... ... ... 0 3 
Total ... 100 
“ Proportion of foreign salts in the soluble substance, 18'1 per cent.” 
The Didn-dna salt lake —is situated about 20 miles to the west of the Ai'vali 
j'ange and 35 miles from the iSambhar lake in a north-westerly direction. It is 
about 4 miles long and 1| miles broad. During the rains there is mostly a foot 
or so of water in the lake, but which soon dries up. When I was there in Nov¬ 
ember it was quite dry, with the exception of a few patches of mud. 
The origin of the lake is similar to that of the Sambhar lake. It i.s situated 
under the lee of a short ridge, between 300 and 400 feet in height above the level 
of the plain, and .so protected from the blown sand, which about here forms long- 
ridges sometimes upward.s of a 100 feet bigb, extending in an east-north-east 
direction. Thi.s is also the direction of the longer axi.s of the lake. 
Two dam.s are built across the lake at about tliree-fourths of a mile from 
either end, to cut off the accos.s of surface water. 
The mode of procuring the salt differ.s from that at the Sambliar lake. At 
Didwana wells of about 6 feet in diameter are sunk in the bottom of the lake to a 
depth of about 15 feet, the bottom of the w-ell is then pierced to a further depth 
of 2 or 3 feet, by a heavy iron-shod pole, when the brine rises suddenly to within 
4 feet of the mouth of the well, at which level it constantly stands during the 
hot weather and the rains. When the wells are first pierced large quantities of 
sulphuretted hydrogen gas are evolved, and even in the old wells the smell of the 
gas is vei-y strong. 
The sections exposed in the wells consist of alternations of sand and sandy 
calcareous tufa. 
The brine from these wells bas a specific gravity of about 1"2. It is lifted by 
tbe clianat, or lever bucket, into shallow pans of about 20 j-ards square and allowed 
to evaporate, when the salt is collected. 
The manager of the works told me that the cost of manufacture was only 
Re. I for 200 maunds. 
The Kadior-Rewassa lake —is situated in Shaikhawati, about 30 miles north of 
the Sambhar lake. It is very shallow, and when I was there, perfectly dry, and 
no manufacture of salt was being carried on. 
F 
