Reference numberMS/119/2/16
TitleSecond half of letter from Charles James Buchanan Riddell, Toronto to Humphrey Lloyd, Trinity College, Dublin
Date27 July 1840
Description[This is a continuation of MS/119/2/14]

Discussion on reason for placing the weak magnet in the declination. Riddell discusses the magnets that are currently being used at the Toronto observatory and their arrangement. Riddell discusses his intentions to remagnetise the bars if necessary, and the forces will be decreased to bring the magnets as close to their position of equilibrium.

Discussion on the vertical force magnet. Riddell asks Lloyd regarding the placement of the decimal points when recording his readings.

The building work on the Toronto observatory has been halted for three weeks. Discussion on the four bars having slight rust on them having been left in the water too long. Riddell regrets not starting his observations on the vibrations immediately after the magnets arrived, to trace their gradual decrease. Discussion regarding the unfinished observatory, and [Edward] Sabine’s proposal to attach another office to the building.

Sabine’s application for [Charles] Younghusband to remain in Toronto to assist with the work at the observatory.
Physical descriptionInk on paper
Access statusOpen
Related records in the catalogueMS/119/2/14
Fellows associated with this archive
NA7327Riddell; Charles James Buchanan (1817 - 1903)1817 - 1903
NA8252Lloyd; Humphrey (1800 - 1881)1800 - 1881
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