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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 pans, 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 may 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, comparable to or exceeding precious stones. The fourth, to
make a compound body of glass and galletyle; that is, to have the colour milky like a chalcedon, being a stuff between a porcelane and a glass.
For the first, it is good first to know exactly the several materials whereof the glass in use is made; window-glass, Normandy and Burgundy, ale-house glass, English drinking-glass: and then thereupon to consider what the reason is of the coarseness or clearness; and from thence to rise to a consideration how to make some additaments to the coarser materials, to raise them to the whiteness and crystalline splendor of the finest.
For the second, we see pebbles, and some other stones, will cut as fine as crystal, which if they will melt, may be a mixture for glass, and may make it more tough and more crystalline. Besides, we see metals will vitrify; and perhaps some portion of the glass of metal vitrified, mixed in the pot of ordinary glass-metal, will make the whole mass more tough.
For the third, it were good to have of coloured window-glass, such as is coloured in the pot, and not by colours
It is to be known of what stuff galletyle is made, and how the colours in it are varied; and thereupon to consider how to make the mixture of glass-metal and them, whereof I have seen the example.
Inquire what be the stones that do easiliest melt. Of them take half a pound, and of iron a pound and half, and an ounce of brimstone, and see whether they will incorporate, being whole, with a strong fire. If not, try the same quantities calcined: and if they will incorporate, make a plate of them, and burnish it as they do iron.
Take a pound and a half of brass, and half a pound of iron; two ounces of the calaminar stone, an ounce and a half of brimstone, an ounce of lead; calcine them, and see what body they make; and if they incorporate, make a plate of it burnished.
Take of copper an ounce and a half, of tin an ounce, and melt them together, and make a plate of them burnished.
Take of copper an ounce and a half, of tin an ounce, of glass-metal half an ounce; stir them well in the boiling, and if they incorporate, make a plate of them burnished.
Take of copper a pound and a half, tin four ounces, brass two ounces; make a plate of them burnished. Take of silver two ounces, tin half an ounce; make a little say-cup of it, and burnish it.
To inquire of the materials of every of the kind of glasses, coarser and finer, and of the proportions.
Take an equal quantity of glass-metal, of stone calcined, and bring a pattern.
Take an ounce of vitrified metal, and a pound of ordinary glass-metal, and see whether they will incorporate, and bring a pattern.
Bring examples of all coloured glasses, and learn the ingredients whereby they are coloured. Inquire of the substance of galletyle.