Reference numberMS/119/2/100
TitleLetter from John Henry Lefroy, Toronto to Humphrey Lloyd
Date8 December 1846
DescriptionLefroy discusses the bifilar coefficient and inconsistencies between them. Lefroy sends a trace of the curves for July. Discussion on the law of changes of force shown by the small and large bifilar, Lefroy suggests running an independent test of the coefficients of force by vibrating a magnet at 10am and 5pm, as well as trying Mr Brown's method of obtaining the coefficients experimentally. Includes a table with quantities and corrected means of both the small and large bif for July 1846. Discussion on the curves monthly mean. Lefroy conveys the importance of establishing a self registering instrument, especially since there have been numerous aurora and disturbances this year. Lefroy mentions [Charles] Younghusband leaving Toronto and assisting Edward Sabine. Lefroy discusses his and his wifes journey, as well as other voyages to America that have not been successful.
Physical descriptionInk on paper
Access statusOpen
Fellows associated with this archive
NA7669Lefroy; Sir; John Henry (1817 - 1890)1817 - 1890
NA8252Lloyd; Humphrey (1800 - 1881)1800 - 1881
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