Small three-quarter plate hollow-back movement, the jeweling in place with cap jewels on balance, lever and escape; the train, escapement parts and the as yet uncut compensation balance in place. The 2-size Lancashire frame stamped with the finishers serial number. 32.5 mm diameter and 7 mm deep, not including arbors, etc.
NB: The 81798 serial number could be that of Brockbank, Atkins & Moore who entered Deck Watch No 81789 in the 1897 Greenwich Trials.
All rough movement are rare survivors. In good clean condition.