| Reference number | NLB/41/347 |
| Alternative reference number | NLB/41 p221 |
| Level | Item |
| Title | Copy letter from Robert William Frederick Harrison, to [Messrs Harrison & Sons] |
| Date | [November 1909] |
| Description | Requests that they prepare an electro of the block illustrating Sir William de Wiveleslie Abney's paper 'on the Change in Hue of Spectrum Colours by Dilution with White Light', for use in the Journal of the Royal Photographic Society. |
| Extent | 1p |
| Format | Carbon |
| Physical description | Typescript |
| Access status | Open |