The Origin of Volcanic Products

Abstract

I HAVE not yet had the advantage of seeing Mr. Mallet's translation of Palmieri's late work on Vesuvius, but have read with interest Mr. Forbes's review thereof and Mr. Mallet's reply in NATURE of Feb. 6 and March 20. I have no desire to enter into a controversy, but as I have for the past fifteen years taught and defended a theory of the origin of volcanic products identical with that now maintained by Mr. Mallet, I may be permitted to say a few words. That the source of all such matters was to be found not in the earth's nucleus but in sedimentary strata, was taught by Referstein in his Naturgeschichte des Erdkörpers, in 1834; and again, doubtless independently, by Sir J. F. W. Herschel in 1837; while, for my own part, I was led to the same conclusion before I became aware of the views of either of my predecessors, solely from a consideration of the varying composition of plutonic rocks and of the stony and vaporous products of volcanic action. To the views of Herschel I first called attention to the Canadian Journal for March 1858, and again in the Quar. Geol. Journ. for November 1859, pp. 488–496, § vii.).