Reference numberMS/119/2/94
TitleLetter from John Henry Lefroy, Longwood, St Helena to Humphrey Lloyd, Trinity College, Dublin
Date6 May 1841
DescriptionLefroy conveys observations and issues in results at the St Helena observatory. Lefroy hopes Lloyd found improvement in observations of the vertical force. Discussion on the times of the vertical plane in January and February being too small. Second apparatus fixed on a pedestal, but Lefroy has not yet made the experiment. Discussion on why Lefroy has not yet made the variations of the vertical force. Discussion on the abstract for the [declination] for April there is a change in the readings not resulted from movement of the telescope, but from the thread having been under a [twist] of 180 degrees.
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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