1835.] Exudation J rom Ghazni. 697 



To the chemist some of this may look superfluous, but I was always 

 suspicious (and thought the fact worth ascertaining), that this singular 

 looking compound might be artificial. 



On platina foil, before the blow-pipe, it turr.ifies with strong effer- 

 vescence, blackens, decrepitates with minute sparks, and passes into a 

 whitish mass. The platina scarcely affected. 



The bran-like matter left from the aqueous and muriatic solution, 



No. 2, was heated in a tube in which litmus and turmeric papers 



with a bit of silver foil were so disposed, that the vapour from the 



assay would pass over them. When heated, a strong ammoniacal 



(burnt feather) smell was evolved, followed by a sickly odour like 



that of turf, or tan refuse. The upper part of the tube was browned 



as from turf smoke. The silver foil and test papers were no way 



affected, proving the absence of sulphur or matters affording ammonia 



in this residuum. 



Analysis. 



In a compound necessarily so variable, little more satisfaction was 



to be expected from an analysis than the test afforded, saving that of 



being convinced that nothing had been overlooked ; 400 grains of it 



gave 



D , , , , . f Nitrate of lime, with a little fatty 1 , nn _ 

 By alcohol and water, < , , .-.■■' J > 162*o 

 ' I animal matter, J 



Nitrate of soda, 23*5 



By muriatic acid, Carbonate of lime, from the rocky fragments, 1365 



Water by anindependantexperiment, 62*0 

 Residuum of dung of birds, with"! 

 a very little siliceous matter and > 95 

 sulphate of lime, J 



3940 

 Loss, .... 6*0 



400 

 Assuming the information on the label to be correct, we may sup- 

 pose that the fissure from which this " rock Chetny" oozes commu- 

 nicates with some limestone cavern frequented by birds, (or in which 

 are large deposits of animal matter,) from which or from the decom- 

 position of the dung, as in many similar situations, the nitrates of 

 lime and soda are formed and gradually ooze out. The presence of 

 the vegetable remains and the absence of all traces of bitumen or 

 sulphur, quite exclude the idea of its being " Mumia," as suggested 

 on the label. 1 have somewhere seen it mentioned, that a nitre cave, 

 as they are commonly called (I think in Kentucky), produces a matter 

 assuming this unctuous, but not the viscid, state, but cannot now 

 recollect the work. 



