| RefNo | MS/119/2/124 |
| Level | Item |
| Title | Letter from E Russell, Makerstoun Kelso to Humphrey Lloyd |
| Date | 9 December 1841 |
| Description | Russell informs Lloyd he is sending the monthly and term day work for November. Russell informs Lloyd he has received the standard barometer and thermometer, and compared the thermometers already in his possession. Discussion on any errors due to the difference in thermometers, however Russell assures Lloyd that these are not very large, but different corrections will need to be made at different parts of the scale. Russell discusses the satisfactory comparisons with the wet and dry, and horizontal force and vertical force thermometers. Discussion on the comparison for the barometers is not yet complete, but Russell notes they have been very unsatisfactory, and possible methods Russell intends to adopt in order to get a fair result. Russell asks Lloyd about what to do with wet bulb thermometers in frosty weather, and discusses the readings from both wet and dry bulbs. Russell describes his work comparing each thermometer independently with the standard thermometers.
Russell was required to insert a new suspension thread, as the suspension roller of the declination instrument had been unwound by the weight of the magnet, the suspension thread came into contact with rough edges of the gap in the copper rings and this caused several of the fibres of the suspension thread to be cut.
Russell informs Lloyd that the term day observations are singularly uniform, and any variation is due to the change in temperature. |
| Extent | 4p |
| Format | Manuscript |
| PhysicalDescription | Ink on paper |
| AccessStatus | Open |
Fellows associated with this archive
| Code | PersonName | Dates |
| NA8252 | Lloyd; Humphrey (1800 - 1881) | 1800 - 1881 |