| Reference number | NLB/55/775 |
| Alternative reference number | NLB/55 p422 |
| Level | Item |
| Title | Copy letter from Robert William Frederick Harrison, Assistant Secretary of the Royal Society; to The Director General of the Ordnance Surveys |
| Date | 19 September 1918 |
| Description | Letter enclosing a set of six diagrams with Mr. Walker's corrections and notes in pencil together with the originals |
| Extent | 1p |
| Format | Carbon |
| Access status | Open |