204

^iLACK LKAD.

says, it was a lead-coloured shining stone, smooth asglass; appeared as if rubbed over with oil; it gave tothe lingers an ash-grey tint, with a plumbeous brightness;and adds, pointed pencils were made of it for the use ofpainters and draughtsmen; that it was then called Flan-ders stone, because it was brought from the Nether-lands to Italy . 3 4 A closer description of the substance thanthis cannot he discovered; agreeing in every particular,except its native soil, and which is accounted for.

Somewhere about three years afterwards, a still more per-fect description was furnished by Imperati, who calls theblack-lead grafio piombino; and he says it is much moreconvenient for drawing than pen and ink, because the marksmade with it appear distinct upon a white ground; also inconsequence of their brightness show themselves on black;but because they may be preserved or rubbed out at plea-sure; also, because one can retrace them with a pen, which,he says, lead or chalk will not admit. This mineral issmooth; appears greasy to the touch; has a leaden colour,which it communicates with a metallic brightness. It canresist, for a long time, the strongest fire, and even from itacquires more hardness; it has in consequence beenthought to be a species of talc. This, in the arts to whichit is applied, is a property that highly enhanceth its value;being manufactured into crucibles, &c. with clay. Thesevessels are capable of standing the strongest heat of a chynii-cal furnace.

Sometimes this lead is foliaceous, and may be crumbledinto small pieces or scales; but frequently found denser andmore strong. This latter is v.lmt writing pencils should bemade of; hut the former being more frequently found, and alsocoining from the refuse of the w'orkmen, is too often mixedup with some glutinous substance, and there is reason tosuppose it to be enclosed in the groove in a pliant state;those pencils are commonly hawked about our streets bypedlars aiid Jews .

Out of this last described lead the before-mentioned ves-sels are also manufactured, being mixed with a clay calledrabrica* From what Imperati has said, we may infer, the

3 Puto motybdoidem esse lapidem quondam iu liigro splendentem colore plum-beo, tactu arieo lubrico, ui perunctus vidcutur, inanasque tangentium inlicit, colorecineieo, non sine uiiquo splendore plumbco ; utunlur eo pictorcs coticnlis in cuspi-dcm exrisis, ad fimiras designandas; appellant autcm lapidem Flandriae quia exBelgio atfertur. l)e mutaUicis libri tres. Noribergir., 1602, 4to. p. 186. Firstedition published in Rome , 1,596, 4to.

4 Dili’ kistoriu nuturalc di ferrante Impevato. In Napoli, 1599, fo. p. 122.