On the following day I met Dr. Frankland in the Finstermuntz pass, and that night we bivouacked together at Mals. Heavy rain fell throughout the night, but it came from a region high above that of liquidity. It was first snow, which, as it descended through the warmer strata of the atmosphere, was reduced to water. Overhead, in the air, might be traced a surface, below which the precipitate was liquid, above which it was solid; and this surface, intersecting the mountains which surround Mals, marked upon them a beautifully-defined _snow-line_, below which the pines were dark and the pastures green, but above which pines and pastures and crags were covered with the freshly-fallen snow. [Sidenote: THE STELVIO. 1856.] [Sidenote: COLOUR OF FRESH SNOW. 1856.] On the 2nd of September we crossed the Stelvio. The brown cone of the well-known Madatschspitze was clear, but the higher summits were clouded, and the fragments of sunshine which reached the lower world wandered like gleams of fluorescent light over the glaciers. Near the snow-line the partial melting of the snow had rendered it coarsely granular, but as we ascended it became finer, and the light emitted from its cracks and cavities a pure and deep blue. When a staff was driven into the snow low down the mountain, the colour of the light in the orifice was scarcely sensibly blue, but higher up this increased in a wonderful degree, and at the summit the effect was marvellous. I struck my staff into the snow, and turned it round and round; the surrounding snow cracked repeatedly, and flashes of blue light issued from the fissures. The fragments of snow that adhered to the staff were, by contrast, of a beautiful pink yellow, so that, on moving the staff with such fragments attached to it up and down, it was difficult to resist the impression that a pink flame was ascending and descending in the hole. As we went down the other side of the pass, the effect became more and more feeble, until, near the snow-line, it almost wholly disappeared.