Page:Theophrastus - History of Stones - Hill (1774).djvu/111

 XXXIX. The different Sorts alo vary from one another in Colour, Compactnes, and Gravity.

XL. As to their Colour, there is a black Kind found on the Sicilian Shores, which is compact and weighty, and omething reembles that kind of the Pyrites called the Molaris: for there is a natural Pumice of this Texture, heavy and compact; and this is of more Value and more ueful than many of the others; this Kind from the Shores is a better Abtergent than the light white Kind: But the mot abtergent of all others, is that from the Sea itelf.