As to calcined lead, it is washed, like stibi[1733] and cadmia. Its action is astringent and repressive, and it is promotive of cicatrization. The same substance is also employed in preparations for the eyes, cases of procidence[1734] of those organs more particularly; also for filling up the cavities left by ulcers, and for removing excrescences and fissures of the anus, as well as hæmorrhoidal and condylomatous tumours. For all these purposes the lotion of lead is particularly useful; but for serpiginous or sordid ulcers it is the ashes of calcined lead that are used, these producing the same advantageous effects as ashes of burnt papyrus.[1735]
The lead is calcined in thin plates, laid with sulphur in shallow vessels, the mixture being stirred with iron rods or stalks of fennel-giant, until the melted metal becomes calcined; when cold, it is pulverized. Some persons calcine lead-filings in a vessel of raw earth, which they leave in the furnace, until the earthenware is completely baked. Others, again, mix with it an equal quantity of ceruse or of barley, and triturate it in the way mentioned for raw lead; indeed, the lead which has been prepared this way is preferred to the spodium of Cyprus.
CHAP. 51.—FIFTEEN REMEDIES DERIVED FROM THE SCORIA OF LEAD.
The scoria[1736] of lead is also made use of; the best kind being that which approaches nearest to a yellow colour, without any vestiges of lead, or which has the appearance of sulphur without any terreous particles. It is broken into small pieces and washed in a mortar, until the mortar assumes a yellow colour; after which, it is poured off into a clean vessel, the process being repeated until it deposits a sediment, which is a substance of the greatest utility. It possesses the same properties as lead, but of a more active nature. How truly wonderful is the knowledge which we gain by experiment, when even the very dregs and foul residues of substances have in so many ways been tested by mankind!
A spodium[1737] of lead is also prepared in the same manner as that extracted from Cyprian copper.[1738] It is washed with rain water, in linen of a loose texture, and the earthy parts are separated by pouring it off; after which it is sifted, and then pounded. Some prefer removing the fine powder with a feather, and then triturating it with aromatic wine.