1825.] Specimens of the Soil of the Cavern of Kiihlock. 293 



examined with the blowpipe gave a small quantity of phosphate 

 only ; lastly, the solution of t])ese crystals precipitated neither 

 oxalate of ammonia nor acidulous nitrate of silver. 



24. When exposed in a glass tube to a gentle heat they 

 decrepitated and effloresced, losing water and some ammonia ; 

 at a higher temperature they yielded ammonia, mixed with au 

 hydrocyanic odour, a little sulphuretted hydrogen and sulphur, 

 and a large proportion of sulphite of ammonia, which crystallized 

 as it cooled in long needles ; this salt was recognised by its 

 taste ; by the sulphurous gas which was evolved by muriatic 

 acid ; and lastly, by the yellow precipitate which it gave with 

 sulphate of copper. The residue of the distillation was entirely 

 soluble in water ; this solution when concentrated was shghtly 

 acid ; but when strongly calcined, it became slightly alkaline ; 

 nevertheless it did not effervesce while dissolving in nitric acid; 

 this solution precipitated platina in the state of a double salt of 

 potash, and with the nitrate ofbarytes it gave sulphate. I con- 

 clude from these experiments that these lamellar transparent 

 crystals were sulphate of ammonia and potash, a double salt 

 first described by Link in 1796. 



Crystals in fine Needles, and of a Straw Colour. 



25. Examined with a glass they appeared to be formed of 

 several kinds of substances; unfortunately I had too few to 

 attempt a separation of them. 



26. These crystals put in excess into distilled water of the 

 temperature of52°Fahr. gave a solution of a pale yellow colour, 

 consisting of water 199 parts and 1 of crystals. This solution 

 was rendered slightly turbid by heat ; gave an abundant precipi- 

 tate of sulphate of barytes witii the nitiate, and of oxalate of 

 lime with the oxalate of ammonia; it gave no chloride of silver 

 \\ith the nitrate; lastly, these crystals were not altered by sul- 

 phuric acid, and yielded ammonia with potash. 



27. O'lo? gramme of the crystals yielded by distillation, first, 

 aramoniacnl water, having an hydrocyanic smell ; secondh', 

 sulphur ; odly, sulphate of ammonia ; fourthly, a residuum, 

 which, after incineration, weighed 0*122 oramme : this dissolved 

 in nitric acid without effervescence, except a few flocks of 

 silica : ammonia precipitated 0-007 gramme of a matter which 

 appeared to be phosphate of lime, magnesia, iron, and manga- 

 nese ; there remained 0'112 gramme of sulphate of lime in 

 solution. 



28. It is evident that the yellow needle-form crystals contained 

 a large proportion of sulphate of lime and a small quantity of 

 yellow colouring principle ; but was this sulphate simply mixed 

 with the sulphate of ammonia and potash, or was in combination 

 with the sulphate of ammonia ? or, lastly, was it mixed with the 



