Take one part of the Regulus of Antimony and four parts of pure Tin; melt them in a crucible and pour them out, and let them cool; this mass makes all iron and steel fusile, therefore when you would melt iron or steel, fill a crucible with either of the metals, set it in a Wind Furnace, and leave it so long in the Coles till all the matter wax highly red hot. Then take off the cover and put into the crucible, half as much of the said mixt mass of Regulus of Antimony and Tin, as the iron or steel put in the crucible weighed, then put on the cover, and cover it over with the Coles, and urge the fire as strongly as ever possibly you can, that so the mass you put in, may cause the iron or steel to melt. When ’tis all well molten, pour it presently forth, least the Tin flying away in fume, leave the molten iron, and so it returned to its former hardness and not suffer it self to be fused.
This matter consisting of the Regulus of Antimony, Tin, and Iron, or Steel, is so hard, that you may strike fire thereout of with a flint.
Now then if you would experiment the abovesaid combustion or burning up, take a good strong crucible made of potters earth, and fill it with salt peter, set it on live Coals so that the salt peter may melt, then having cast your tin and iron in the form of small rods, heat one end of the rods so as not to melt, hold the other end in a pair of Tongs, and put it into the molten salt peter, that the iron together with the tin and Regulus of Antimony may be burnt up as if it were wood, and vanish away with the flame into a fume. For almost all tin and iron are a meer sulphur, and being consumed by the flame, leave nothing else in the crucible save Scoria’s, which being washed with water, and boiled on a cupel or test with lead and blown off, do leave behind, the true gold and silver hidden in both metals.
For when by the flame of so pure a salt peter, the impure sulphur of the iron and tin is burnt up, it must necessarily be that what good soever was in the metals do remain behind.
I do not therefore here set down this operation, as if I would thereby promise any one golden mountains. No such matter. For I onely manifest these, and such like labours meerly for this end, that every one may know, that salt peter being brought to a requisite purity, is wont to burn up imperfect metals as one burns up wood; and it may be easily gathered thencefrom, that such a pure salt peter doth as to its virtues much exceed the common peter.
As for such like labours of burning up the imperfect metals by salt peter purified in a due manner, and of getting pure gold and silver with profit, they shall be taught in the following Century (God willing.)
For even as this first Century doth for the most part treat of fire and salt; so the chiefest part of the following Century shall treat of the wonderfull and great efficacy of purified salt peter in destroying, and reducing metals, and that with great bettering of them, and with no small profit. And albeit I was desirous of inserting in this first Century, such like profitable betterings of the metals, yet it could not well be done; principally because that there are many other things concerning the profitable use of the con-centrated spirits of salt, that I must necessarily pass over here, because the number of this Century is already up, and therefore must I refer them to the following Centuries.
And forasmuch as there is frequent mention made in this Century, of glasses and crucibles, which none can be without in the preparing and use of these moist fires, because of the many hazards and losses wherewithal common instruments are accompanied, for they often break, or else easily let out or spill the boiling matters; it is altogether requisite that I should here have manifested this excellent invention of mine, which preventeth all such discommodities; and which I hinted at in the second part of my Miraculum Mundi.
But whereas I have bestowed both those inventions there on the poor, of meer gift, it would be an unjust thing to take away from them what is theirs; nay rather they should have by good right more bestowed on them. So then being not able to proceed any farther as to this case, this thing onely remains, viz. an affirmation that neither Medicine nor Alchymy can want or be without such excellent Inventions. But yet if any one desires to have them, he may write to those two men, to whom I have given them, that they may trade for the poor; whatsoever any one that is desirous of knowing those secrets shall bargain with them for, he will not be repulsed but obtain his desire, and purchase from them the secret; the which process I will nevertheless describe, omitting the naming of the matters.