But that we may get a certain knowledge of distinguishing the said stones, I think it altogether necessary to treat of them more at large.
Therefore although this kind of stones are plentifully enough, to be found every where in the World, yet they are not known, or regarded, because we cannot perswade our selves, that there is any the least portion of Salt-petre contained in them; for albeit, that an hundred pounds of such stone should contain in it ten pound of Salt-petre, and we should reduce the same into a most subtile powder, and should labour to extract from thence a Lixivium or Lee, with either cold or hot water, yet should we not hereby get so much as one Ounce of Salt-petre. The reason is this, because there is not to be found in such a stone as soon as ever it is digged out of the earth, any Corporal Salt-petre, which may be extracted by means of water, but there lies hidden only a certain Soul or Magnet of Salt-petre, by the virtue of which, that which gives a Corporeity thereunto is to be first attracted out of the air, to the end that Salt-petre may arise thencefrom. And this is hereby evident, for were it otherwise, and were there in that stone any Corporeal Petre at the first digging, it must necessarily be extracted thencefrom by the help of water; but we find it impossible to make any such extraction, unless that stone be before laid for some certain time in the air, and doth, together with its softness, acquire (or make) Salt-petre in a Magnetical manner.
But for all this, we know that this our reason so exceedingly well founded, will not yet satisfie the unskilful, unless we make it yet more clear unto them with other Expressions, and various Examples; but I pray how is it possible to declare all such Circumstances to one that is utterly ignorant. ’Tis too much labour to boil Meat for another, and to thrust it into his Mouth too. It is surely sufficient enough to have shown the truth, and discovered the way by which the operation is to be contrived, though all things be not founded on such palpable Reasons.
But forasmuch, as the work, which I treat at present of, is an altogether new thing, and unknown to any men, the necessity of the thing requires, that we do a little more openly and clearly exhibit (and set down) the whole knack.
We presuppose, that it is a thing well known already, even to all, that each thing hath in it its peculiar magnet, by the benefit of which, it attracteth unto it self from the air, or earth, whatsoever is profitable for it; and especially, because we have largely treated thereof in our Works; insomuch, that we deem it altogether needless to repeat the same here. However ’tis requisite that I add thus much, viz. That the Minerals do abound with a certain Magnetick Virtue, more than other things do; and that they do attract their Life, Figure, or Shape, and Essence, out of the air, like as the Animals do, that so they may be nourished, and encrease; but being destitute, or deprived thereof, they are observed to be as it were dead, and bound, or wholly void of vigor.
As for Example. Let the Minera, or Ore of Vitriol, or Alum, be digg’d out of the Earth, that the Vitriol, or Alum in this Minera, be already duly digested and ripened, the salt may even presently be extracted thereout of, with common water. But if they have not as yet attained their full maturity, there is no salt extracted thence, unless the Minera be first torrified, or calcined. Nay more, a Minera, or Ore, that is yet less ripe, will not yield any Salt, neither by the force of the fire, nor without it; but must be yet farther exposed to the air for some time, that so it may first attract that out of the air, that is requisite to make Vitriol or Alum of, and thus (these things being first done) the Alum, or Vitriol, is most easily gotten thereout of, by a convenient Extraction and Evaporation.
We made mention in the second part of the Philosophical Furnaces, of a certain Minera, or Ore of Vitriol, which is plentifully found at [Herckeroda in Hassia] sticking in that Earth, which in that place they make their Crucibles or Pots, in great quantity with; and we shewed a way of making a red and sweet Oil of Vitriol thereof, yet with this Caution, viz. That we shall not have from the said Minera, not the least portion at all of this Oil, if we do not expose it, broken in bits, to the cold air, for half a year, that so it may fall into powder. Such as have heeded this going to work, have made thereof amost sweet Oil; but such as have neglected the doing this, which I published out of a sincere heart, and have reduced the said Mineral into fine powder, and laboured to extract a salt thencefrom, by boiling it in simple water, bestowed their labour in vain, because of their refusing to expose that Minera for a while to the air, and they received not so much as one Grane of Vitriol; and thereupon they took occasion to slander me, and to accuse me of Lying.
But now, when they have observed that this Mineral that they cast away, being exposed to the air, had attracted therefrom a salt by its Magnetick Virtue, when it had lain so long as to mould into powder of its own accord, and that thereout of a Vitriol doth proceed, they were enforced to believe that there lay hidden some Vitriol in those stones; which notwithstanding, could not be extracted by means of water, and so they have afterward publickly confessed, that what they afore gainsay’d, or oppos’d, was agreeable to the truth.
Thus likewise, there are various sorts of Copper (Ores) endued with an attractive power, and upon that account, there cannot be separated any Metal, by fusion, when it is first taken out of the Earth, unless we have first exposed it for some Months unto the Air.
Every Nitrous Earth, out of which Salt-petre hath already been extracted, doth (when it is again exposed to the air) attract Salt-petre anew, and this we observe to happen in all Wood-ashes, but especially in Lime-stones Calcined; for, it attracteth more salt out of the air, than its weight was afore its being Calcined. For, at the first time, you will scarce get ij. or iij. ℔. of salt out of a centenary, or hundred weight; now by how much the longer it lies exposed to the air afterwards, so much the more plenty of salt doth it yield, as is sufficiently well known already. He that is ignorant of that we speak, or else cannot understand it, let him make trial, and he shall find that what we say is a truth. Such as are Ideots do extreamly need these kind of Admonitions, that so, the business being the better understood, we may take from them all occasion of ignorantly detracting from my Writings.