| Name and Model Number | Burt's rule |
| Country of Origin | U.K. |
| Date of Manufacture | ~1895 |
| Front Scales | Coggeshall variant |
| Back Scales | Tables of weight, railway rates, and wood measure |
| Scale Length | 11" |
| Type of Rule | Rule |
| Construction | Boxwood and brass |
| Area of Use | Other |
| Comment | A 2-foot, 2-fold rule for transport using the railways.
Burt’s rule, with its very idiosyncratic collection of tables and measures, and a patent that was never awarded, is probably the rarest of the 2-2 slide rules |
| Rarity | RRR |
| Donor | Collection of an English gentleman |
| Match Number | 39 |
| Thumbnail |  |
| RR | = Rare -- 1 of 25 collectors has one; it may take a year to find an example in the marketplace. |
| RRR | = Very rare -- only very few known to collectors; may take several years before one comes up for sale. |
| RRRR | = Extremely rare -- a museum piece; unlikely that an example will ever come up for sale. |