Reference numberMS/119/2/11
TitleLetter from Charles James Buchanan, Toronto to Humphrey Lloyd, Trinity College, Dublin
Date1 May 1840
DescriptionRiddell updates Lloyd on the building of the Toronto observatory. Only the foundations had been dug so far, therefore Riddell was able to alter the azimuth according to Lloyds results. Discussion on the azimuth of the axis of the building, the new position, and the position it was in before. Includes a small diagram of the proposed building with little detail on the position of the vertical force instrument, horizontal force instrument and the transit room.

Riddell notes it has been three months since he first made absolute determinations, however there were causes that rendered the first inclined to error.

Discussion regarding Riddell resetting the plane of the vertical force. Riddell informs Lloyd that he has moved one of the magnetometers to the site of the observatory.

Riddell discusses putting up a conductor from the anemometer, and that it shouldn’t be placed on the observatory itself, as he had previously intended. Riddell asks Lloyd’s opinion on the placement.

Discussion on the axis of the building.
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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