OCT. — DEC. 1856.] The Natron Lake of Loonar. 19
No. 8. Quartz.
No. 9. Greenish brown glas?, very fusible.
No. 1. This salt appears to be formed in crystalline masses, and is but slightly contaminated by chloride of sodium, or by any other insoluble impurities ; these, exclusive of the water present, will amount to about 4 per cent.
No. 2. Fine cubical crystals, forming jmasses, in which the pe- culiar structure may easily be tracecf ; this salt contains something more than 92 per cent, of j3ommon salt, or chloride of sodium.
No. 3. Has less crystalline structure than No. 1 ; is efflorescent and white in appearance. Chemical constitution shows a larger amount of water, while the so3a and carbonic acid are nearly in the proportions required to form neutral carbonate.
No. 4 is formed by the aggregation of numerous small crys- tals, is whiter than No. 1, but has almost the same chemical con- stitution as No. 3.
No. 5 appears in larger dirty looking masses, is not homogene- ous in its composition ; in parts, it possesses a beautiful structure, seen in crystals radiating from a centre : contains 16 per cent, of water, 25 per cent, of common salt, and 30 per cent, of insoluble impurities.
No. 6. A greyish looking earth, containing 58 per cent, of in- soluble impurities, 15 per cent, of water, 2^ of common salt, leav- ing 26 per cent, of carbonate of soda.
No. 7. A salt varying from all the other specimens, being com- posed of earthy (not wlkaline) carbonates chiefly, some insoluble impurities, a little common salt.
No. 8 not examined, it evidently consists of crystallized silicic acid, known as quartz.
No. 9. A readily fusible glass, most probably chiefly a silicate of soda, not examined chemically, scratches window glass.
I have made no remarks respecting commercial value, as this must necessarily depend on various circumstances, concerning
