The firm of S Davall & Son Ltd of 262/266 St John's Street Clerkenwell, London was registered December 1931.
Their "Tower" clock movement was shown at the 1933 trade fair and claimed to be the smallest striking clock on the market.
A version with quarter chime and self correcting gear was introduced in 1932.
In 1937 a new night silent Westminster chime was introduced.
Production appears to have ceased at the beginning of WW2.
In "Collectable Clocks", by A and R Shenton, which has a fair sized entry about Davall clocks, the authors quote several identifying features and there is an illustration of a lantern type clock made to commemorate the coronation..
Shenton appears to consider Davall an above average maker.