Surface Film of Aluminium

Abstract

IN NATURE of May 7, p. 673, I have read with a good deal of interest an account of some experiments made on aluminium foil which had been treated by the Bengough anodic process. In some experiments made on ordinary aluminium foil in connexion with a research on the determination of oxide in aluminium, details of which work was published in the Jour. Soc. Chem. Ind., vol. 45, p. 170, the writer, in collaboration with Miss H. E. Millar, had previously made the same observations as Messrs. Sutton and Willstrop. In our experiments, and employing the same method, it was even possible to notice the film on such thin foil as 0.00075 in. in thickness, and moreover we were able to identify surface markings on the layer which were originally present on the original metal. Messrs. Sutton and Willstrop are probably unaware that we had previously made this observation, and therefore the correctness of our conclusions becomes the more certain.