Reference numberMS/119/2/7
TitleLetter from Charles James Buchanan Riddell, Toronto to Humphrey Lloyd, Trinity College, Dublin
Date4 March 1840
DescriptionRiddell informs Lloyd that he has not had word from England in some time due to steamers not sailing. Sailing will commence from Halifax from 1st May to take mail, and Riddell hopes to be in regular communication. Discussion on the delays in constructing the Toronto observatory. Riddell informs Lloyd that he will be constructing a building from logs rather than stone, and its advantages. Using stone will cause delays as well as greater expense. Discussion on the different types of stone. Riddell describes additional office delays that he did account for, and discusses an advertisement placed in a radical newspaper rather than the government published paper, and the delays this caused. Riddell is looking forward to moving into more comfortable quarters, and would like to hear from Lloyd before the work on the building begins. Discussion on Lloyd’s four equations explaining the condition of equilibrium. Riddell discusses Lloyd’s plan for observations at Toronto.

Discussion on instrument adjustments. Riddell has been working on the temperature corrections and other preliminaries before adjusting the bifilar. Riddell discusses the declination magnets.

Riddell discusses observations taken on the last Friday of January.

Riddell hopes that this will be his last letter discussing nothing but delays and notes he has not gained any experience in the last three months owing to this.

An aurora occurred last Friday during the observations and caused a significant change in the readings. Riddell is curious to trace the connection and see if other stations correspond.

The torsion force in the declination magnet is now adjusted. Discussion on the varied strength of Riddell’s magnets.
Physical descriptionInk on paper.

The letter has two holes where presumably the wax seal has been broken. The wax seal has been removed.
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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