Reference numberMS/119/2/56
TitleLetter from Charles James Buchanan Riddell, Woolwich to Humphrey Lloyd
Date4 October 1844
DescriptionRiddell is sending Lloyd, [Henry] Lefroy’s northern observations, and would be thankful if Lloyd could particularly look over those relating to the induction inclinometer. Riddell lists the observations that he has sent. Observations included are of the declination bifilar and induction inclinometer at Fort Simpson, Mackenzie, term day observations, report of adjustments at Athabasca and Fort Simpson, and disturbances. Discussion on the induction inclinometer, and its construction which made the iron bar close to the magnet than usual.

Riddell discusses his observations from October 1843, and the increase in permanent magnetism.

Discussion on the first connected services of inclinometer observations.

The two bar instruments have been sent to all of their stations. Riddell recommends changes to instruments of low latitude in future use.

Riddell asks Lloyd to look over his paper and instructions regarding temperature corrections.

Riddell met with [Johann von] Lamont recently at Woolwich and recounts the points that struck him. Riddell describes Lamont observing the declination and intensity with an extremely compact portable instrument.

Discussion on the Toronto volume, and delays on printing.
Physical descriptionInk on paper
Access statusOpen
Fellows associated with this archive
NA7327Riddell; Charles James Buchanan (1817 - 1903)1817 - 1903
NA8252Lloyd; Humphrey (1800 - 1881)1800 - 1881
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