| RefNo | MS/119/2/99 |
| Level | Item |
| Title | Letter from John Henry Lefroy, Toronto to Humphrey Lloyd |
| Date | 15 February 1841 |
| Description | Lefroy discusses his arrival in Canada in October [1840], he notes there have been no disturbances for the past six months at the Toronoto Magnetic and Meteorological Observatory, and therefore he is still ignorant of all the characteristics of this station. Discussion on Lloyd's suggestion that they should discontinue the regular turn days and rely on extra observations, and Lefroy mentions Dr [Alexander Dallas] Bache from the Philadelphia observatory did not agree with this. Discussion on lack of funds for the Philadelphia observatory which is in Lefroy's opinion the best in the United States. Discussion on the observatory in Washington. Lefroy compares the observatory at Philadelphia with Toronto. Lefroy sends results of experiments on Lloyd's [tatical] needle in comparison with Mr [Robert Were] Fox's needles for measuring small changes of total force [not enclosed].The results show that Lloyd's needles are much more superior for this task. Discussion on new instructions by [Edward Sabine] that have been acted on. Discussion on changes to the apparatus and problems with it. Discussion on Sabine's St Helena observations that show an effect of the moon's daily passage on the mean pressure . Discussion on the magnetic survey. |
| Extent | 4p |
| Format | Manuscript |
| PhysicalDescription | Ink on paper |
| AccessStatus | Open |
Fellows associated with this archive
| Code | PersonName | Dates |
| NA7669 | Lefroy; Sir; John Henry (1817 - 1890) | 1817 - 1890 |
| NA8252 | Lloyd; Humphrey (1800 - 1881) | 1800 - 1881 |