Dictionarium Polygraphicum. Arsenick.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol I.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
1735ARSENICK, is a ponderous mineral substance, extremely caustic or corrosive to the degree of a violent poison.

There are divers kinds of Arsenick, viz. yellow or native red, and crystalline.

Native Arsenick is of a yellow or orange colour; whence it is also call'd auripigmentum or orpiment.

It is chiefly found in copper mines, in a kind of glebes or stones, of different sizes and figures.

As to the colour, though it is always yellow, yet admits of divers shades and mixtures, as a golden yellow, reddish yellow, green yellow, &c.

It is found to contain a small quantity of gold; but so little as not to quit the cost of separating. Of this are prepar'd two other sorts of Arsenick white and red.

Red Arsenick call’d Realgal, is only the native yellow rubified by fire.

The white or chrystalline, is drawn from the yellow by subliming it with a portion of sea salt.

White and yellow Arsenick, are also procurable from cobalt, the method of which as practis'd in Hungary, is as follows.

The cobalt being reduc’d to powder, and the light sandy part wash'd off by a current of water, what remains is put into a furnace; the flame of which passing over the powder takes the arsenical part along with it in form of a smoke; which being receiv'd by a chimney, and carried thence into a close brick channel, sticks by the way to the sides, and is scrap'd off in form of a whitish or yellowish powder. From what remains of the cobalt, they proceed to make smalt.

The smallest quantity of any of these Arsenicks, being mixt with any metal renders it friable, and absolutely destroys its malleability.

Hence the refiners dread nothing so much as Arsenick in their metals; nor could any thing be so advantageous to them as a menstruum, that would absorb or act on Arsenick alone; for then their metals would be readily purified, without flying off or evaporating.

A single grain of Arsenick will turn a pound of copper, into a beautiful seeming silver; this hint many persons have endeavour'd to improve on, for making of silver, but in vain, because it could never be brought to sustain the hammer; and some have been hang'd for coining species of this spurious filver.