1851 Great Exhibition: Official Catalogue: Class X.: E. J. MacDoual
67. MACDOUAL, E. J., 12 Dorset Place, Pall Mall East — Inventor and Manufacturer.
Patent escapement for chronometers, watches, and clocks, without escape wheel. The same spring by India-rubber.
Drill-stocks: Archimedean; centrifugal Archimedean; vibrating; and duplex, simple, and centrifugal.
A new method of converting rectilinear into rotary motion.
A new decomposition cell. Medals made by the process.