[ n I 



ing this feveral times, I obtained a full drachm of 



perfect cryftals, which diminifhed in their fize as the 



procefs advanced; and afterwards a fcruple more of 



thin lamellae, which on examining with a magnifying 



glafs appeared to be made up of imall fquare cryftals ; 



there remained a fmall quantity of a fait ley, which 



probably would have yielded a few more fuch lamella; 



The liquor which remained after the two firfl 



parcels of fait were feparated, was next evaporated * 



but no pellicle appearing, the operation was continued 



till it was quite dry, when it formed one tranfparent 



yellow or amber-coloured ..fait cake, which weighed 



one drachm and 34. grains. This fait on being put 



into a tea cup, prefently began to run per deliquium y 



and difTolved entirely by ftanding in a cupboard which 



was in a room where there was a fire ; but the fire 



having been let .out in the evening, and the night 



proving cold, I found next morning that a cryftallifa- 



tion had taken place, for there was a cryftallifed cake- 



at the bottom of the cup, which was covered with an 



amber-coloured leys it at firft feemed to be all one 



piece, with a number of , fmall points ftanding up on> 



its furfaces j but on reclining the tea cup to a fide, it 



then appeared to be made entirely up of a number of 



oblong cryftals about the length of a barley-corn, but? 



not . fo , thick, and. that the points beforementioned. 



were the ends of thefe cryftals. Not having time to. 



examine them particularly in the morning, and to, 



know their exact; figure and number of fides, I fet 



them by, till I fhould come home again, about one, 



o'clock ; but the day proving warm, they were moft- 



\y difTolved before that time. 



Oil of vitriol, dropt into a tea cup in which there 

 was. fome of .this ley, immediately occafioned a white 



