Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/150

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It is easier to shew, that these characters are for the most part erroneous, than to substitute others more precise, and consequently better, in their stead: a negative truth is however in my opinion always of some value.

Monte Rosa is we know, next to Mont Blanc, the highest mountain in Europe; there being a difference of only ninety-six feet between them. All mineralogists and geologists agree that it is an assemblage of primitive mountains. Brochant does not state the extent of that vast deposit of newer serpentine which he tells us exists at Zoeblitz in Saxony; I think however, that a circuit of mountains of serpentine, the internal diameter of which is thirty thousand feet, and which is bounded by walls, if I may so express myself, fourteen thousand five hundred and eighty feet high, cannot be considered as a deposit of very limited extent.

As a cap of eternal snow completely covers the upper part of the mountain, it is only by analogy we can say that the serpentine reaches to the top, it can however be traced to a very considerable height. I have observed it myself at ten thousand four hundred and sixteen feet above the level of the sea, at the fort of St. Theodule, in the passage of Mont Cervin. This may serve as a reply to the assertion of Brongniart, that the serpentine of oldest formation does not rise very high. He does not omit, it is true, to mention Monte Rosa as an exception, but he has forgot to produce a single example in support of his opinion. The potstone which is found at Alagna at the foot of Monte Rosa, at the height of three thousand eight hundred feet above the level of the sea, may be considered, I think, by all