| Description | Having completed his diary from last year, Dobbs has copied it to send to Jurin. He describes the location of Castle Dobbs above the Bay of Carrickfergus, its latitude, and surroundings. He notes that the diary is composed in columns, according to Jurin's formula ['Invitatio ad observationes meteorologicas communi consilio instituendas', by James Jurin, Philosophical Transactions of the Royal Society, v.32 (1723), pp.422-427]. His portable barometer is by Maple of Dublin, after Hauksbee's in London. The thermometer is also by Maple, after Hauksbee. His hygrometer was of whip cord and he had no means to compare it with the moisture in London. He prepared a vane for the wind, according to the description in volume 2 of Lowthorp's Abridgement [of the Philosophical Transactions] on p.42, but eventually found that he could estimate wind force of gusts by calculating the mean. He records when clouds move differently from the wind direction, or in calm, with the aspect of the sky. Dobbs describes his method of collecting rain. The thermometer was in a room, but he moved on the few occasions when a fire was required. He concludes by hoping that the observations will be of use.
Endorsed [p.4]: 'Mr. Dobbs Jan. 18 1726/7 Arthur'. |