Aluminium and tin may be melted together in all proportions to give uniform fluid mixtures. The melting cannot be done in the ordinary fireclay or
plumbago crucibles, since the admixture of tin appears to increase greatly the power which aluminium has to reduce the silicates of fireclay, the
reduced silicon becoming absorbed in the body of the metal. In our earlier experiments on these alloys we learned that, even with careful melting at a
temperature not higher than about 750° C., it was impossible to prevent this rapid reduction of silicon. In a few minutes the alloys became badly
contaminated with the m etalloid; in one instance as much as 11 per cent., partly crystalline and partly amorphous, was found in the cooled ingot.
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