Reference numberMS/119/2/15
TitleLetter from Charles James Buchanan Riddell, Toronto to Humphrey Lloyd, Trinity College, Dublin
Date27 August 1840
DescriptionRiddell updates Lloyd on the work undertaken at the Toronto observatory. Riddell has sent Lloyd the observations for last month [not enclosed], he discusses his results, and how he has recorded the curves. Discussion on the curve of May and June observations. Riddell discusses the placement of the telescope which gives a very fair angular value, and suggests making the tube longer at both ends and giving a greater range to the scale. Lloyd confirms the need for a separate building to house the anemometer.

Discussion on Henry’s experiments at the [Magnetic and Meteorological Observatory, Girard College] Philadelphia, in which bars in a spiral were, magnetised at a distance of 12 feet.

Riddell notes that building the observatory has been delay after delay, but the work should finish at the end of the week, and intends to move in next week.

Riddell asks Lloyd about the number on the long scale sent by [Thomas] Grubb.
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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