Papers on meteorology : relating especially to the climate of Britain, and to the variations of the barometer / by Luke Howard.

  • Howard, Luke, 1772-1864.
Date:
1850-1854
Catalogue details

Licence: Public Domain Mark

Credit: Papers on meteorology : relating especially to the climate of Britain, and to the variations of the barometer / by Luke Howard. 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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    32* ON A REMARKABLE DEPRESSION OF THE BAROMETER IN NOVEMBER 1840, AGREEING VERY CLOSELY IN ITS MOVEMENTS AND RESULTS WITH THAT OF DECEMBER 182F*. The commencement of the present winter was attended with stormy weather, causing serious inundations and many shipwrecks; since which we have had a long and severe frost. The barometer showed in part of the months of October and Novem- ber, in a remarkable degree, that rarefaction or loss of quantity in the European atmosphere, which is always more or less connected with these rapid and extensive movements: and there appears in nearly the whole of the phsenomena a close corre- spondence with former atmospheric changes, in November and December 1821. Of these I gave an account to the Society in January 1822, which appeared in the Philo- sophical Transactions for that year, p. 113f. On the 13th of November 1840, in the present case, the pencil of my clock baro- meter, after about thirty days of desultory variation tending downwards, had attained, at 8 p.m., the very low point of 28'03 inches. A very good upright barometer indicated at the same time 28'20 inches, which is probably nearer the true minimum, though I think rather above it. I have already stated elsewhere, that from the imperfect construction of the instrument the pencil on my clock ranges about 12 hundredths of an inch at each extreme beyond the scale,—a circumstance which however affects but little the results I am about to draw from its indications, as compared with each other. From the low point above mentioned, began a rise carrying the curve in twenty- four hours up to 29-10 inches; and in about twelve hours more it had reached 29 40 inches, or the part of the scale from which this rapid fall had commenced. A second depression of 8 tenths, and a corresponding elevation followed; after which the curve went up in two days by desultory movements to about 30 inches. Prom the 19th (where this occurs) to the 22nd we have another instance of rapid depression to below 29 inches, followed by as rapid a recovery. The movement then takes a bold swell of a week’s continuance, carried up to 3036 in., where we leave it; observing that the present results were obtained at Ackworth, Yorkshire, the former at Tottenham. My first thought on discovering the barometer so near the bottom of the scale, * Read before the Royal Society on the 11th of March, 1841. See Proceedings, No. 47 (vol. iv. p. 292). [f Reprinted in the present collection, p. 13a.]