356 Miscellanies. 



the face of the fortress in that direction, with a cream colored deposit; 

 nay, the hill itself on which the old city was built, 50 feet high above 

 the plain, may probably have been raised in the same way, the pres- 



ent small lake being only the remains of a much larger one formerly 

 level with the plain; and this may explain why the present lake ap- 

 pears to be fathomless. The hill thus raised by the waters became 

 eventually covered by a noble city, the ruins of which are now in 

 turn covered more or less by the calcareous deposit. 



28. Limestone with Shells. — At Kerefto there are vast caverns 



wrought by art in limestone, or natural caverns enlarged and modi- 

 fied by art ; in this limestone were remains of shells ''resembling 

 cockles, and of nearly the same size ;" the caverns were very nu- 

 merous and curiously wrought.— Vol. II, pp. 550, &c. 



29. Limestone Promontory on Island Oroomia- — It rises 800 

 feet high out of the lake, and is an island in the winter when tlic water 

 is high, but becomes a peninsula when it is low. It is called Gooro- 

 hin Shala. It has been made a fortress, and has but one entrance into 

 its natural or artificial caverns, in which there is abundance of the 

 most pellucid fresh water in a rock rising out of one of the saltest 

 lakes in the world; The ridge of the rock is scarcely six feet broad, 

 and while the observer stands upon it at the giddy height of 800 feet 

 above the azure Oroomia, the hollow roarings of whose waters dash- 

 ing into the caverns they have worn through the rock at its base, 



serve to increase his nervous giddiness. 



30. Mica containing Potash and Litliia, — M. V. Regnault has analyzed 

 these micas; they fuse easily at a red heat, and without sufTerincj any 

 sensible loss of weight, and are afterwards easily reduced to a fine pow- 

 der. 



The analysis was performed by acting upon the mica, previously fused 

 and reduced to fine powder, with hydrochloric acid, and separating the 

 silica in the usual way. The alumina and peroxide of iron were precip- 

 itated together by carbonaie of ammonia; the liquors being evaporated, 

 after the addition of sulphuric acid, left a residue, which, when calcined, 

 yielded the alkaline sulphates, which were dissolved in water, and decom- 

 posed by chloride of barium. The excess of barytes added was after- 

 wards precipitated by dihue sulphuric acid, added gradually; and the 

 solution containing the alkaline cldorides, after the addition of chloride 

 of platina, was evaporated nearly to dryness. By the addition of alcohol, 

 the double chloride of potassium and platina was separated; the lithia 

 was determined by difference, and by the composition of the sulphates. 



