Note 1706 — BOOK XXXIV. THE NATURAL HISTORY OF METALS. (continued 2)

We may conclude that the “plumbum nigrum,” or “black lead” of Pliny is the Galena or sulphuret of lead of the moderns; it is frequently what is termed argentiferous, i.e. united with an ore of silver, and this in such quantity as to cause it to be worked for the purpose of procuring the silver.—B. See Beckmann, Vol. II. p. 210.