ce Oa 
liar preparation of solidi , called alum ores. 
At Tolfa, near Civita-Vecchia, where Wink itivn stars 
af is made, the ore is alum-stone, or sulphuretted clay, found © 
in large stratified masses among compact iron-shot las 
it large strated but at ees ae 
nent of Europe and in Great Britain, it is manufactured 
from pyritaceous clay, which is in black, hard, brittle 
iecinlih dices aluminous ores, a white saline earth 5 
‘shale alum slate, which occurs amorphous, or in concentric 
balls. At Hurlett, near Paisley, the largest alum mine in 
Britain, the schistus lies ten inches thick above the coal 
beds. An alum i is found near Moscow, which contains 
ted by Dr. Hoffinan, who denied that it it could — 
be detected in these waters, in their natural state ; after- 
“ wards ascertained that martial vitriol, or sulphate of iron, 
“38 gives these waters a sourish taste, and had probably been 
‘= ~ mistaken foralum. Yet Dr. Layard assures us, that the 
ee ae Somersham chalybeate, in the county of Huntingdon, in 
— had contains alum. Dr. Morris obtained it from this 
eo erent sath, Seperation of five grains, in crystals 
= %. of alum, to two pounds of water. Dr. Rutty suspects that 
s*S the mineral water at Ballycastle, in the county of Antrim, 
“2 in Ireland, contains a pittance of alum. i 
ae It has been supposed by Mr. A. T. Thompson, that alum 
__ -was unknown to the ancients, since the erurrig of the 
a Greeks, and the alumen of the Romans, were mere vitriol 
ic earths. lsh. by the Asaticy n the mid to have 
been by the esietion ie the ages 
of alast callenbieeat ae re - 
Europe was supplied, seg gy 
works were andseve at Tolfa aa Voter lin a ober 
= Satire im that country, are t on, the estates. 
of Lord 5 ah Saleh: soe Seaeareeaee Dowd 
and Mul; reat Whitby, nthe same nty. The best 
octohedral masses, powdery on one ae contains 
- no ammonia in its composition. i ciaaheva, in eulie 
eS ee ee 
—— Gray, 
