The metallic salt is first prepared; it is added to the coloring and talciform earth, the mixture is allowed to digest with phosphoric acid and a lime is obtained; metallic which, over high heat, flows into a translucent glass or resembles a slag.
It only lacks the fuel39 for this slag to be a real metal. It was mixed with charcoal powder and subjected to the fusion fire in a tightly closed refractory retort. We then get the real metal.
37 This experience should be compared with the previous ones. Note the qualitative and quantitative multiplication procedures. It would be wrong to take this projection powder for the result of a "particular". The author has here in view not the principle salt, but the harmoniac salt, useful in the wet way, indispensable in
the dry voice. It is naturally insoluble in ordinary water. He will come back to this later, in the chapter on pyrites.
"Brennbar". To understand what the author hears, we must refer to what he says about charcoal and the principle that
