| RefNo | RB/1/10/46 |
| Previous numbers | BP 10, fols. 63-4 |
| Level | Item |
| Title | Fragment of the original version of 'Usefulness'. |
| Date | 1650s or early 1660s |
| Description | MS version of section of text on experiments with aqua fortis, partly published in section V of Essay X, partly unpublished (in order 64, 63).\r\nHand: rounded 1650s |
| Language | English |
| Extent | Fols. 63-4 (2 leaves) |
| Format | Manuscript |
| AccessStatus | Open |
| RelatedMaterial | 'Works', vol. 6, pp. 533-4.\r\nPreviously unpublished section in 13, pp. 307-10 |