Note 23 — PRINCIPLES OF CHEMISTRY CHAPTER XV THE GROUPING OF THE ELEMENTS AND THE PERIODIC LAW
George Kamensky translation
As an example we will take indium oxide, In2O3. Its sp. gr. and sp. vol. should be the mean of those of cadmium oxide, Cd2O2, and stannic oxide, Sn2O4, as indium stands between cadmium and tin. Thus in the seventies it was already evident that the volume of indium oxide should be about 38, and its sp. gr. about 7·2, which was confirmed by the determinations of Nilson and Pettersson (7·179) made in 1880.