Floating of Solid on Molten Metal

Abstract

I OBSERVE in NATURE (vol. xviii. p. 397) a note of some experiments on this subject. The results of these experiments (unless with lead) are, I think, very similar to some which I have made, and described in your pages (see NATURE, vol. xvi. p. 23), viz., that with heavy pieces the metal first sank and then rose to surface; with light pieces the “skin” formed on the surface of the ladle was sufficient to keep them afloat. From these experiments I drew the conclusion that the cold solid metal was specifically heavier than the molten metal, but after a short immersion, depending on size of pieces, these pieces had expanded by the great heat around them so as to have their bulk increased sufficiently to enable them to float. My experiments with solid pieces of lead showed that they sank and did not come to the surface, and could be felt lying at bottom. Pieces of sheet lead rolled up floated.