Volume 1

The gallery of nature and art; or, a tour through creation and science / [Edited] By the Rev. Edward Polehampton [assisted by distinguised writers in the various departments].

Polehampton, Edward (Edward Thomas William), 1777?-1830.

Date:: 1817

Credit: The gallery of nature and art; or, a tour through creation and science / [Edited] By the Rev. Edward Polehampton [assisted by distinguised writers in the various departments]. Source: Wellcome Collection.

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$brandies of the same rivulet which do not pass immediately near these fissures, remain cool and limpid; and thus you may with one hand touch one rill that is at the boiling point, and with the other hand touch another rill which is of the usual temperature of water in that climate. The exhalations of sulphur do not at all times proceed from the same fissures, but new ones appear to be daily formed, others becoming, as it were, extinct. On the margins of these fissures, and indeed almost over the whole place, are to be seen most beautiful crystallizations of sulphur, in many spots quite as fine and perfect as those from Vesuvius, or indeed as any other specimens I have ever met with. The whole mass of decomposed rock in the vicinity is, in like manner, quite penetrated by sulphur. The specimens which I collected of the crystallized sulphur, as well as of the decomposed and undecomposed porphyry, were left inadvertently on board the packet at Falmouth, which prevents my having the pleasure of exhibiting them to the Society. I did not perceive at this place any trace of pyrites, or any other metallic sub* stance, except indeed two or three small fragments of clay iron- stone at a little distance, but did not discover even this substance any where in situ. It is very probable that the bed of the glen or ravine might throw some light on the internal structure of the place; but it was too deep, and its banks infinitely too precipitous, for me to venture down to it. I understood that there was a similar exhalation and deposition of sulphur on the side of a mountain not more than a mile distant in a straight line; and a subterranean communication is supposed to exist between the two places. \De Borda, Journaldes Mines, Geological Transact. Vol. I.] CHAP. XVI. ISLANDS SUDDENLY THROWN UP PROM THE SEA. Besides the convulsions of nature displayed in volcanoes, other operations are carried on below the fathomless depths of the sea, the nature of which can only be conjectured of by the effects pro-$