Page:Theophrastus - History of Stones - Hill (1774).djvu/293

 cloed by a Crut formed of the Matter within; and o well topped, that no Vapour ecaped.

After this the Retort became corroded in a great many Places: Fumes iued, at them all, for a little While; but they were afterwards topped by Cruts of the fame Kind as the former.

When the Operation was finihed, there were found in the upper Part of the Retort a Kind of Flowers, dry and powdery; and in the Neck a thick, limy, moit Subtance.

The Retort was corroded all round, jut above the Top of the Reiduum; and this corroded Part crumbled to Dut between the Fingers; having lot the Nature of Glas.

Here then is found a Foil capable of diolving Glas; a Power not known in any other Body:

Subliming an abolute Stone during the Ditillation; a Quality equally unknown in other Bodies:

And burning with a violet, centles Flame: A Thing equally unknown; and the more trange, as the Stone holds no Copper.

To hew the violet Flame, ome of the Stone is to be broken mall with a Hammer; and prinkled on a red hot Heater, in the dark: The Flame ries very freely, and continues ome Time; and the Stone plits into thin irregular Flakes

The Ues of the pure Acid may be infinite: And it is eay to ee the Knowledge of this Subject will lead us to a thouand unknown Truths in the Mineral Hitory. The