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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    Winds from the south, south-east and west prevailed under the apogee on twenty days, under the perigee on thirty-eight days. The winds from the south-west show thirty-one days for the higher, and but twenty- four for the lower apsis. In the remainder, and in the calm days, there is no marked preponderance; and if we class together the south-west and north-west with the va- riable, and divide the latter between them, the account shows an equal number for each. The fair inference from the whole, on the concurrent evidence of the vane, the ba- rometer, the thermometer and the rain-gauge, appears to be this,—That in the climate of London, as now treated of (and the precise or apparent limits of which we have yet to determine), the moon in her perigee brings over us the southern atmosphere, which, on the whole of the effects, tends to lower the density and raise the tem- perature of the air, occasioning also a larger precipitation of rain : That the apogee, on the contrary, gives occasion to a freer influx of air from the northward, by which we obtain, on the whole of the effects, a higher barometer, with a lower temperature and less rain—subject still to an occasional compensation by a large addition to the rain under this apsis—and that, occurring twice in a cycle of nine years (at the times when also the extremes of wet and dry take place) upon the whole account of the year. But the phaenomena here exhibited cannot be finally appreciated without reference to the connexion of the apsides with the phases of the moon, and of both with the declination. I have treated this last cause already, and shown its effects on the den- sity, temperature, winds and rain of our climate in the very dry year 1807, and the very wet one of 1816*; but I now purpose to resume the inquiry into its compara- tive influence through the cycle of nine years which I have in hand; and I may possibly be able also to treat briefly the subject of the combined effects of the three causes on the whole of the phaenomena of our seasons, but in this I still feel that I greatly need the help of minds prepared by the requisite familiar acquaintance with astronomical science. Tottenham, April 11, 1840. [* See ‘Climate of London,’ vol. i. p. 181-197.]