| Reference number | MS/257/4/72 |
| Alternative reference number | Sa.1201 |
| Previous numbers | ES4/1/1201 |
| Level | Item |
| Title | Letter from Edward Sabine, 13 Ashley Place to [John Frederick William] Herschel |
| Date | 8 May 1858 |
| Description | Regarding magnetic observations at the Cape of Good Hope, Hobarton and Toronto. Discusses the observatory at the Cape of Good Hope, refers it was burnt down in 1852 and has not been rebuilt since, describes the monthly determinations of the dip and horizontal force. Sabine has completed the laws of declination disturbances, as well as ‘the lunar diurnal variation of the declination’. Discusses the laws Sabine intends to examine next.
Discussion regarding the Hobarton observations which Sabine notes were ‘terminated some time ago’. Refers to a proposition made to the colonial office for the continuation of the observations.
Discusses the observations at Toronto.
Sabine addresses his opinions on ‘what is to be done next and what is to be expected’ regarding the ‘researches to be methodically prosecuted’. Remarks on the Astronomer Royal’s opinion on the papers regarding what has been done. Discusses the results that have been obtained by the colonial observations, referring to ‘the discovery of the decennial period of the magnetic disturbances’. Refers to [François Jean] Arago’s observations. Discussion regarding solar spots.
Sabine remarks it is difficult to make ‘a just estimate of the comparative estimate of results so recently arrived’ in science which is yet in its infancy. Describes ‘the next most important discovery’ in Sabine’s opinion referring to the confirmation that the earth’s magnetic force is greatest when it is ‘nearest to the sun’.
Refers to the translation of the Cosmos. Discusses recent observations in North America, and the ‘secular movement of translation of the isoclinal and isogonic lines’. Refers to the ‘disturbances’ of the three magnetic elements, the ‘diurnal magnetic variation’ caused by the moon, the importance of magnetic surveys.
Remarks on ‘admirable devotion’ of Captain [Rochfort] Maguire and officers who carried out observations on board ‘HMS Plover’ at Point Barrow. |
| Extent | 12p |
| Format | Manuscript |
| Physical description | Ink on paper |
| Access status | Open |
Fellows associated with this archive
| Code | Name | Dates |
| NA8279 | Sabine; Sir; Edward (1788 - 1883) | 1788 - 1883 |
| NA8238 | Herschel; Sir; John Frederick William (1792 - 1871); astronomer | 1792 - 1871 |