068v - - - - - [continued]
and immediately you will be able to crumble it between your fingers and to easily grind it in a metal mortar, or better yet, in an iron one. Next, it will be easy to grind it, not only on common marble that would corrode, but on porphyry, and it is necessary that it be finely ground with water so that when putting it on your fingernail, you find it soft without any asperity like the colors that the painters grind for oil. You can use au lii this one, once dry, in a box mold instead of sand, without moistening it with anything nor reheating it. If you do not like it, fumigate the cavity with sulfur smoke or de p with the tip of the flame of a wax candle that barely makes smoke, and it will make a very neat & shiny & polished work, in pure lead & tin. I would say the same for finely pulverized tripoly that does not want to be not reheated or moistened. Burnt linen gives less trouble than others, because it does not need to be reheated, nor moistened, & molds and releases very neatly & very, subtlety & releases well neat, like the previous ones & withstands several castings. First you ought to burn it with a flame, then leave it to rest & to be consumed with its fire until it is completely dead, then finely grind it on marble or on a paper. But because a lot And if you reheat it in a crucible, red hot due to the fire, to render all of it fine & impalpable, I believe it will be even better. But because a lot of linen is reduced to very little when burned, if you want to save some, you can sprinkle only the medal that you want to mold & cover it, and fill the box mold with crushed slate, which molds also very neatly, but note that the first cast is always the most beautiful & the neatest. If you cast at your convenience soft tin that seems to be burnished in little wheels that pewterers sell, comes out very neatly & approaching the color of silver, without mixing in anything else, it is true that one ought to cast it rather hot, & so that the molded object should be four fingers away from the cast. In order to know its heat, first melt it well, so hot with such a degree of heat that it promptly burns a paper or straw placed inside, by simmering. Then remove it from the fire & leave it to rest a little & cast the tin mixed
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