IG The Natron Lake of Loonar. [xo. 1, new series, 
A fresh portion of salt was dissolved, and treated by a little ni- 
tric acid ; after effervescence and filtration, solution of nitrate of 
baryta was added — no reaction — absent sulphuric acid. Phosphoric 
acid being evidently in small quantity, if present at all, was not 
looked for. The preliminary examination of each sample of salt 
was conducted in a similar manner. 
Guided by the qualitative examination above shown, the quan- 
titative determinations were carried out. The usual methods 
adopted by chemists were empfoyed throughout in these determi- 
nations. To ascertain the constitution ^f the salt, some special 
experiments were required. Frezenius and Will's method for the 
determination of the carbonic acid was ntade use of, to ascertain 
whether it was really a sesquicarbanate with the formula 2 N&O, 
3 CO 4 like the natural compounds of soda( and carbonic acid in 
Africa, or whether it had the more ordinary formula of the neutral 
or bicarbonate. These experiments showed in the c?se of the 
" Dulla" salt, that there is a mixture of carbons te and sesquicar- 
bonate, in the proportion of 54 per cent, of the neutral carbonate 
and 30 per cent, of the sesquicarbonate ; but in the others, a neu- 
tral constitution was found to exist, as exhibited by the formula 
NaO, CO 2- The point of interest connected with the constitution 
of the Dulla salt is purely a scientific one, since natural sesquicar- 
bonates are very rare, having hitherto been found only in Fezzan 
in Africa, in the soda lakes of Hungary, and in Venezuela, South 
America ; to this list we may now however add the Loonar lake in 
the Nizam's country. An artificial sesquicarbonate can only be 
obtained with difiiculty, and under certain conditions involving a 
very careful employment of temperature. 
The following is a statement of the composition of the several 
specimens of salts from the Loonar lake, calculated on 100 parts. 
No. 1. " Dulla." 
^ 83-82; equal to 77-30 of neu- 
tral carbonate consisting of — 
31'48 cf carbonic acid 
y 45-82 of soda. 
Carbonic acid 38 00 
Soda 45-82 
77-30 neutral carbonate an- 
hydrous. 
