| Popis: |
Mr. T. V. Barker has lately shown that the parallel growth of isostructural substances upon one another is conditioned by similarity of molecular volume. This very important conclusion invites further investigation from this new point of view, and Professor H. A. Miers suggested to me, while working in his laboratory last summer, that I should make experiments on the parallel growth of sodium nitrate on the pseudo-rhombohedral mineral barytocalcite.The first experiments, which were made on crystals of barytocalcite in the Oxford collection, were unsuccessful, the crystals employed being small and somewhat impure. Later, I received, from the Museum of Practical Geology in London, some very good and perfectly pure crystals of barytocalcite from Blagilt, near Alston, in Cumberland. |
