90 



On the Fossils of the Eastern Portion 



common salt and a little sulphate without any carbonate of soda, which 

 is no doubt produced in the same manner as the Lonar salt. I did not 

 ascertain whether it was also a sesquicarbonate, but I have examined a 

 portion of native carbonate of soda from another part of India, with 

 which Mr. Faraday had the kindness to furnish me, and I found it to be 

 composed of a mixture of that salt with muriate of soda and a little sul- 

 phate. The same is probably true of the carbonates found in other 

 countries in similar situations*. A specimen, however, procured from 

 the water of a deep well near London, passing through the London clay 

 into the chalk, which I received from Professor Daniell, contained the 

 carbonate ; but as the sesquicarbonate is decomposed by a low heat, no 

 inference can be founded on the examination of specimens obtained, as 

 this was, from the boiler of an engine. 



The absence of Lime in the water of the Lonar Lake is a remarkable 

 circumstance, but easily accounted for, as the sesquicarbonate of soda 

 and the water itself precipitate the sulphate and muriate of lime, not- 

 withstanding the mutual decomposition they undergo when in a semifluid 

 state. The Lake of Ourmia, in Persia, is stated by Dr. Marcet to con- 

 tain no lime, although of a specific gravity of 1 165-07, and abounding in 

 sulphates and muriates. This appeared very remarkable in an inland sea 

 nearly 30O miles in circumference, situated in a volcanic country. On 

 referring to the works of travellersf , it appeared that the streams flowing 

 into it abounded in lime, which is deposited in large quantity in the form 

 of a beautiful travertine. The lake is shallow, and at certain seasons 

 much of it is nearly dry ; the water is clear and transparent, but the mud 

 of the bottom is loaded with sulphuretted hydrogen, and thick layers of 

 salt, formed in it under the water, are redissolved on any agitation. No 

 fish can live in it. All these phenomena are exact counterparts of those 

 exhibited at Lonar, but no information is given as to the salt collected 

 fi:om its saline mud, except that Sir John Malcolm states, the salts are 

 bitter and different from those of the sea. I am, therefore, strongly im- 

 pressed with the conviction, that sesquicarbonate of soda is formed from 

 its waters as at Lonar, and precipitates the lime. Dr. Marcet, however, 

 has given, in the Philosophical Transactions for 1819, the results of an 

 examination of a small quantity of this water, which he states to be as 

 follows ; 



* The carbonate of soda formed by the incineration of saline* plants in the deserts of 

 Northern India, and by the deflagration of nitrate of soda and charcoal in the south ot 

 the Peninsula, must not be confounded with the natron found in the soil. 



+ Sir John Malcolm's History of Persia; Sir Ker Porter's Travels ; Ouseley's Travels ; 

 Journal of the Geographical Society, vol. iii. &c. 



