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Inquisitions touching the compounding of metals. To make proof of the incorporation of iron with flint, or other stone. For if it can be incorporated without over-great charge, or other incommodity, the cheapness of the flint or stone doth make the compound stuff profitable for divers uses. The doubts may be three in number.
First, Whether they will incorporate at all, otherwise than to a body that will not hold well together, but become brittle and uneven ?
Secondly, Although it should incorporate well, yet whether the stuff will not be so stubborn as it will not work well with a hammer, whereby the charge in working will overthrow the cheapness of the material ?
Thirdly, Whether they will incorporate, except the iron and stone be first calcined into powder? And if not, whether the charge of the calcination will not eat out the cheapness of the material ?
The uses are most probable to be; first for the implements of the kitchen; as spits, ranges, cobirons, pots, etc. then for the wars, as ordnance, portcullises, grates, chains, etc.
Note; the finer works of iron are not so probable to be served with such a stuff; as locks, clocks, small chains, etc. because the stuff is not like to be tough enough.
For the better use, in comparison of iron, it is like the stuff will be far lighter: for the weight of iron to flint is double and a third part; and, secondly, it is like to rust not so easily, but to be more clean.
The ways of trial are two: first, by the iron and stone of themselves, wherein it must be inquired, what are the stones that do easiliest melt. Secondly,
with an additament, wherein brimstone is approved to help to the melting of iron or steel. But then it must be considered, whether the charge of the additament will not destroy the profit.
It must be known also, what proportion of the stone the iron will receive to incorporate well with it, and that with once melting ; for if either the proportion be too small, or that it cannot be received but piece-meal by several meltings, the work cannot be of value.
To make proof of the incorporating of iron and brass. For the cheapness of the iron in comparison of the brass, if the uses may be served, doth promise profit. The doubt will be touching their incorporating; for that it is approved, that iron will not incorporate, neither with brass nor other metals, of itself, by simple fire : so as the inquiry must be upon the calcination, and the additament, and the charge of them.
The uses will be for such things as are now made of brass, and might be as well served by the compound stuff; wherein the doubts will be chiefly of the toughness, and of the beauty.
First, therefore, if brass ordnance could be made of the compound stuff, in respect of the cheapness of the iron, it would be of great use.
The vantage which brass ordnance hath over iron, is chiefly, as I suppose, because it will hold the blow, though it be driven far thinner than the iron can be; whereby it sayeth both in the quantity of the material, and in the charge and commodity of mounting and carriage, in regard, by reason of the thinness, it beareth much less weight : there may be also somewhat in being not so easily over-heated.
Secondly, for the beauty. Those things wherein the beauty or lustre are esteemed, are andirons, and all manner of images, and statues, and columns, and tombs, and the like. So as the doubt will be double for the beauty ; the one, whether the colour will please so well, because it will not be so like gold as brass ? The other, whether it will polish so well ? Wherein for the latter it is probable it will; for steel glosses are more resplendent than the like plates of brass would
be; and so is the glittering of a blade. And besides, I take it, andiron brass, which they call white brass, hath some mixture of tin to help the lustre. And for the golden colour, it may be by some small mixture of orpiment, such as they use to brass in the yellow alchemy; it will easily recover that which the iron loseth. Of this the eye must be the judge upon proof made.
But now for páns, pots, curfews, counters, and the like, the beauty will not be so much respected, so as the compound stuff is like to pass.
For the better use of the compound stuff, it will be sweeter and cleaner than brass alone, which yieldeth a smell or soiliness; and therefore may be better for the vessels of the kitchen and brewing. It will also be harder than brass, where hardness may be required.
For the trial, the doubts will be two: first; the overweight of brass towards iron, which will make iron float on the top in the melting. This perhaps will be holpen with the calaminar stone, which consenteth so well with brass, and, as I take it, is lighter than iron. The other doubt will be the stiffness and dryness of iron to melt; which must be holpen either by moistening the iron, or opening it. For the first, perhaps some mixture of lead will help. Which is as much more liquid than brass, as iron is less liquid. The opening may be holpen by some mixture of sulphur: so as the trials would be with brass, iron, calaminar stone, and sulphur; and then again with the same composition, and an addition of some lead; and in all this the charge must be considered, whether it eat not out the profit of the cheapness of iron ?
There be two proofs to be made of incorporation of metals for magnificence and delicacy. The one for the eye, and the other for the ear. Statue-metal, and bell-metal, and trumpet-metal, and string-metal; in all these, though the mixture of brass or copper should be dearer than the brass itself, yet the pleasure will advance the price to profit.
First therefore for statue-metal, see Pliny's mixtures, which are almost forgotten, and consider the charge.
Try likewise the mixture of tin in large proportion with copper, and observe the colour and beauty, it being polished. But chiefly let proof be made of the incorporating of copper or brass with glass-metal, for that is cheap, and is like to add a great glory and shining.
For bell-metal. First, it is to be known what is the composition which is now in use. Secondly, it is probable that it is the dryness of the metal that doth help the clearness of the sound, and the moistness that dulleth it; and therefore the mixtures that are probable, are steel, tin, glass-metal.
For string-metal, or trumpet-metal, it is the same reason ; save that glass-metal may not be used, because it will make it too brittle; and trial
be made with mixture of silver, it being but a delicacy, with iron or brass.
To make proof of the incorporation of silver and tin in equal quantity, or with two parts silver and one part tin, and to observe whether it be of equal beauty and lustre with pure silver; and also whether it yield no soiliness more than silver? And again, whether it will endure the ordinary fire which belongeth to chafing-dishes, posnets, and such other silver vessels ? And if it do not endure the fire, yet whether by some mixture of iron it may not be made more fixt? For if it be in beauty and all the uses aforesaid equal to silver, it were a thing of singular profit to the state, and to all particular persons, to change silver plate or vessel into the compound stuff, being a kind of silver electre, and to turn the rest into coin. It may be also questioned, whether the compound stuff will receive gilding as well as silver, and with equal lustre ? It is to be noted, that the common allay of silver coin is brass, which doth discolour more, and is not so neat as tin.
The drownings of metals within other metals, in such sort as they can never rise again, is a thing of great profit. For if a quantity of silver can be so buried in gold, as it will never be reduced again, neither by fire, nor parting waters, nor otherways: and also that it serve all uses as well as pure gold, it is in effect all one as if so much silver were turned into gold; only the weight will discover it; yet that taketh off but half of the profit; for gold is not fully double weight to silver, but gold is twelve times price to silver.
The burial must be by one of these two ways, either by the smallness of the proportion, as perhaps fifty to one, which will be but six-pence gains in fifty shillings; or it must be holpen by somewhat which may fix the silver, never to be restored or vapoured away, when it is incorporated into such a mass of gold; for the less quantity is ever the harder to sever: and for this purpose iron is the likest, or coppel stuff, upon which the fire hath no power of consumption.
The making of gold seemeth a thing scarcely possible; because gold is the heaviest of metals, and to add matter is impossible : and again, to drive metals into a narrower room than their natural extent beareth, is a condensation hardly to be expected. But to make silver seemeth more easy, because both quicksilver and lead are weightier than silver; so as there needeth only fixing, and not condensing. The degree unto this that is already known, is infusing of quicksilver in a parchment, or otherwise, in the midst of molten lead when it cooleth ; for this stupifieth the quicksilver that it runneth no more. This trial is to be advanced three ways. First, by iterating the melting of the lead, to see whether it will not make the quicksilver harder and harder. Secondly, to put realgar hot into the midst of the quicksilver, whereby it may be condensed, as well from within as without. Thirdly, to try it in the midst of molten iron, or molten steel, which is a body more likely to fix the quicksilver than lead. It may be also tried, by incorporating powder of steel, or coppel dust, by pouncing, into the quicksilver, and so to proceed to the stupifying.
Upon glass four things would be put in proof. The first, means to make the glass more crystalline. The second, to make it more strong for falls, and for fire, though it come not to the degree to be malleable. The third, to make it coloured by tinctures, compar. able to or exceeding precious stones. The fourth, to