| RefNo | MS/119/1/123 |
| Level | Item |
| Title | Letter from Humphrey Lloyd, Fitzwilliam Square, Dublin to Edward Sabine |
| Date | 4 November 1847 |
| Description | Lloyd has been busy with [Trinity] College examinations therefore unable to reply to Sabine’s letter. Lloyd does not prefer the microscopes to the mirror scale in the balance magnetometer, but he has not used that instrument in a long time finding it ‘hopeless’ and does not have any improvements.
Discussion on the induction inclinometer and Lloyd’s confidence it it’s ability to function adequately. Lloyd refers to the Director of the St Helena observatory and notes the immediate readings of the induction inclinometer are made together with the declinometer, and that the changes of inclination depend on the difference of the arc changes. Lloyd informed Riddell that the process in the instructions for obtaining the coefficient for the induction inclinometer should not be relied upon. [Johann von] Lamont has devised a similar but better method, and Lloyd will write to Sabine describing the particulars soon. The results achieved by Lamont’s method are independent of the permanent polarity if the iron bars.
‘Cooper has determined differences of longitude by means of shooting star’. |
| Extent | 6p |
| Format | Manuscript |
| PhysicalDescription | Ink on paper |
| AccessStatus | Open |
Fellows associated with this archive
| Code | PersonName | Dates |
| NA8279 | Sabine; Sir; Edward (1788 - 1883) | 1788 - 1883 |
| NA8252 | Lloyd; Humphrey (1800 - 1881) | 1800 - 1881 |