| RefNo | HS/19/175 |
| Level | Item |
| Title | Notes on [Thomas] Maclear "base" work to measure the Arc of Meridian, by Sir John Frederick William Herschel |
| Date | 1840s |
| Description | Note in Sir John Frederick William Herschel's hand summarising the work conducted by Thomas Maclear in South Africa for a baseline to measure the Arc of Meridian and correct the previous arc calculated by Abbé Lacaille.
Includes the triangulation method with landmarks of reference, specifically for the Zwartland Plain, [Swartland] and Saldanha Bay and Schapen Island [Schaapeneiland]; also includes the list of people "at work": [Thomas] Maclear; Charles [Piazzi-]Smyth; Captain [Alexander] Henderson; Lieutenant Cust?; [William] Mann noted 'occasionally'. |
| Language | English |
| Extent | 2 pp. |
| PhysicalDescription | Ink on paper |
| Digital images | View item on Science in the Making |
| AccessStatus | Open |
Fellows associated with this archive
| Code | PersonName | Dates |
| NA8238 | Herschel; Sir; John Frederick William (1792 - 1871); astronomer | 1792 - 1871 |