| Reference number | MM/11/148 |
| Level | Item |
| Title | Copy of a letter from Lieutenant Yule, Bengal Engineers, Aden, to the East India Company |
| Date | 22 September 1840 |
| Description | On the poor condition of the instruments with which he was expected to make magnetic observations and the resulting effect on establishing an Observatory in Aden. |
| Extent | 7 sides |
| Format | Manuscript |
| Access status | Open |
| Related material | See MM/11/149, MM/11/150-151, MM/11/191 and MM/11/193 |