III. — Remarks on a late Paper in the Asiatic Journal on the Gyp-
sum of the Himalaya. By the Rev. R. Everest.
In the July No. of the Asiatic Journal, there is some information given us on the gypsum of the Himalaya, for which the thanks of all lovers of geology are due to the writer (Capt. Cautley). But as it is accompanied by a theory of the formation of gypsum in general, which seems to have been hastily adopted, and which a more mature consideration of the subject would probably induce him to reject, I shall make no apology for pointing out what I believe to be his error, lest others should be misled by his authority.
Having stated a doubt among geologists respecting the gypsum of the Alps, viz. whether it is primitive or transition, he proceeds to describe the gypsum of the Himalaya, and having done so, thus express- es his opinion as to its origin.
" A question of considerable interest arises from the appearance and position of the above-mentioned deposits, which, as mentioned in a former part of this paper from their position under rocks of the primary and secondary classes ac- quire an appearance of antiquity, not borne out by the general history of the mi- neral ; viz. that the gypsum throughout the globe is simply an infiltration ana- logous to the tufa, and calcareous deposits ; and depending on causes chemically similar ; the sulphuric acid being the active generator instead of the carbonic. If in the proximity of sulphur an excess of oxygen would produce sulphuric acid, a difficulty is removed, and the contact with lime-rock, or carbonate of lime would, it may be supposed, produce its sulphate or gypsum ; and I cannot perceive the impro- bability of such a process having been, or being still in force ,• or that nature's labora- tory might not have been as active in the dissemination of gypsum, as it is in the present day, of the calcareous tufa." — vide p. 293. And again, p. 295. " If there- fore, where carbonate of lime, sulphur, and water are abundant, the chemical change above-mentioned is allowed, or is supposed from analogy, to be a probable con- sequence, gypsum can no longer be entitled to a place in either primary, tran- sition, or secondary classes ; but must be considered as an adventitious formation common to all ages, and produced by causes analogous to the present rapid for- mation of calcareous tufa. Among our primary and transition rocks, none can be assimilated to the stalactitic carbonate of lime ; among our secondary or latest class of general rocks, there is none like the gypsum, that is to say, we know of none actually forming at this day. Causes that led to the formations of such abundance of gypsum formerly may, from unassignable reasons, no longer exist ; and those which produce the tufaceous carbonates, then at rest, may now be in full vigor."
Did the writer, when he thus proposes as original the opinion of the formation of sulphuric acid from the proximity of sulphur and water, forget that it is the common solution of one of the most common phoenomena in geology, I had almost said, in nature; and never
