258 Ml', H. M. "Witt's Chemical Examination of certain 



Its specific gravity was 1'18812, and ou evaporation it gave a 

 total quantity of solid residue amounting to 21856'5 grains in 

 the gallon ! 



In the imperial gallon (of 70,000 grains) there were present 

 10470-439 grains of chlorine, corresponding to 17254-27 grains 

 of common salt ; the remainder of the saline matter, amounting 

 to 4602-23 grains, consisted chiefly of alkaline carbonates, but 

 also contained small quantities of the sulphates and carbonates 

 of lime and magnesia ; the smallness of the quantity of water 

 in my possession prevented the possibility of determining their 

 actual amount. 



To indicate the position of the Lake of Urumia among natural 

 brines, 1 append a Table showing the specific gravities, total quan- 

 tities of solid residue, and of common salt, in the gallon of several 

 of the mineral springs of Harrogate (analysed by my friend Mr. 

 Northcoteand myself for, andunder the directionof,Dr.Hofmann), 

 as well as of other brine-springs, and the waters of certain seas. 



* Pfaff,Schwartze's.i4%emeiweMWc?spmeWeHei/g?/eZfeKZeAre. Leipsic,1839. 

 t Laurens and Schweitzer, Phil. Mag. Ser. 3. vol. xv. p. 51. 

 X Pliil. Mag. for 1855, vol. ix. p. 39(), " Ou the Temperature and Den- 

 sity of the Seas between Southampton and Bombay." 



§ Hofmann, Quart. Jourii. of Chem. Soc. vol. vii. p. 161. 

 II Marcet, Nicholson's Journal, vol. xx. p. 25. 

 t Northcote, Phil. Mag. Jan. 1855. 



