Making and Knowing
A minimal edition of BnF Ms Fr 640

[TOC] | [diplomatic]

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Casting gold

Take a crusol that can contain a certain amount, as you wish to place roughly crushed borax into it. Place the borax at the bottom and then the gold on top of it. Arrange the coal in the forge in such a way that the wind of the bellow will blow above the crusol and no on its side as it would cool it down and would not heat it enough. Also, make sure it is three good fingers away from the wall of the forge so that it is quite surrounded by coal. Allow the crusol to anneal until it is quite red. Then, have your boy strongly blow the bellow with long pushes, as in this manner it heats it better. Meanwhile, once the gold will be melted, blow a small bellow above it. Because otherwise the gold would turn sour and would acquire some kind of coat. As long as there will be some swirling smoke as you blow this way, it means that it is not soft enough for the cast. Therefore, uncover the melting pot and without displacing it and without stopping the bellow, tilt it towards you so you may well see what is inside. Throw a ferue of borax in it and blow wind towards it with the small bellow in a jerky fashion. Should there be coal inside, blow a bit stronger to make them come out. And if the gold still smokes and swirls, add borax again and blow above it. Beware that it is still sour and not soft enough, it will show a coat when you blow it as if it had cooled down. By contrast, if it does not show this sign, it is soft enough. Then, blow strongly so that it the gold is quite heated and once you think it is hot enough, throw colour on top of it in the crusol and the colour should be composed as following: verdigris, saltpeter, sal ammoniac, and a bit of borax. And continue blowing with the small bellows, and the gold will turn shiny like

at left top margin

If you cast in gold some piece of important dimensions, lute your mold with the same sand or put crocum on it.

at left top margin

If you wish to cast some large work, or of important dimensions, create at the bottom or at an extremity of the forge a vented furnace where you may hold your mold in the sand so red.

at left middle margin

One may cast two or three pounds of gold.

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