On the temperature of the earth and sea, in reference to the theory of central heat : a lecture, delivered at the Royal Institution, February 20th, 1846, Lord de Mauley, V.P. in the chair / by Alfred S. Taylor.

  • Taylor, Alfred Swaine, 1806-1880.
Date:
1846
Catalogue details

Licence: Public Domain Mark

Credit: On the temperature of the earth and sea, in reference to the theory of central heat : a lecture, delivered at the Royal Institution, February 20th, 1846, Lord de Mauley, V.P. in the chair / by Alfred S. Taylor. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    13 PERMANENTLY HIGH TEMPERATURE OF MINES. gressive rise until we have passed below 50, GO, or 80 feet at the least. Since Dr, Forbes’s experiments were performed, in 1819-1822, the Cornish mines have been considerably deepened, and nume- rous observations have been made by Mr. Fox, principally, in the years 1837-1839 Taking the deepest mines, Mr. Fox found that the thermometer rose, on the average, 1° for every 49'6 feet. Similar experiments made by Captain Oats gave a result of an increase of 1° forevei7 48 feet of descent from the surface. Hence the results of Dr. Forbes’s experiments were corroborated, twenty years after their perlbrmance, by those of Mr. Fox and Captain Oats: thus leading to the important con- clusion, that the ratio of increase in descending the Cornish mines continued very uniform for that long period. The trans- mission of heat from the interior of the globe does not, there- fore, appear to be subject to any great disturbing influences; and we have in this an additional proof, that it must be wholly independent of solai’ influence. The fluctuations of temperature are great above the invariable stratum, but in the same locality they are insignificant below it. At the bottom of one of the deepest mines of Cornwall, Mr. Fox found that the temperature of the rock of a gallery, observed for a period of eighteen months, continued uniformly at 7 0°. The ratio of increase given in the table is only an average. In one Cornish mine, 1200 feet deep, it was 1° in 43 feet; in another, not far distant, 1° in 77 feet. These differences are probably due to tbe different degrees of conductibility in the rocks and strata; for experiments lead to the conclusion, that in the same mine there is little or no fluctuation. It is not sui-prising that a difference in the results shoifld be obseiwed in different strata. In the salt mines of Cheshfle, which are less than 500 feet in depth, the increase is 1° for 70 feet. The water of the coal mines of the North of England has been found to give results more nearly approaching to those obtained in Cornwall. One of tbe deepest mines in England is that of Monkwear- mouth in Durham. Some year’s since, when the depth of this