MEMOIRS 



OF 



THE GEOLOGICAL SURVEY OF INDIA 



The Alkaline Lakes and the Soda Industry of Sind. 

 By G. de P. Cotter, B.A., Sc.D. (Dub.), F.G.S., 

 Superintendent, Geological Survey of India. 



CHAPTER I. 



INTRODUCTORY. 



THE soda industry of Sind appears to have existed from time 

 Introduction. immemorial, although it has attracted little 



notice, on accoimt of the smallness of the 

 output. No scientific examination has hitherto been made of these 

 deposits, but certain samples of alkali were analysed in 1901 in the 

 laboratory of the Reporter on Economic Products to the Govern- 

 ment of India (Mr. I. H. Burkill). In the maps of the Survey 

 of India, published from 1860 to 1863 (scale 1"=1 mile), one of 

 the lakes of the desert is marked " Natron producing." 1 The soda 

 is also described as Natron in the first edition of the Sind Gazetteer 

 published 1874. 2 "In the desert portion of Khairpur " says the 

 Gazetteer " are pits of natron — an impure sesquicarbonate of soda 

 and always found containing sulphate of soda and chloride of sodium. 

 It is generally obtained by means of evaporation. These natron 

 pits are a source of income to the ruling Mir, as many as a thousand 

 camel-loads of this substance being annually exported to Northern 



1 Sheet 43, Sind Surve}', scale 1*=1 mile. 



2 Sind Gazetteer, 1874, p. 407. 



( ^02 ) B 



