The crucible is of metal and considerably larger than the ingot, the latter being surrounded by a mass of unreduced material which protects the crucible from the intense heat.
The silver in this case is obtained as a yellowish grey heavy powder, which is easily washed by decantation; but it' tends to retain unreduced chloride, which can be removed only by fusion with carbonate of soda.
It was taken by the French in 1751, and was retaken in 1752 by Clive, after which it proved invaluable to the British, especially when Lally in his advance on Madras left it unreduced in his rear.
A dry method of purification consists in a liquation on a hearth of peculiar construction, which occasions the separation of the unreduced bismuth sulphide and the bulk of the other impurities.
Q 1 The Unreduced Generating Function Which Enumerates The Covariants Of Degrees 0, 0' In The Coefficients And Order E In The Variables.