This clock was made by Charles O’Keenan, later better known for his work on electricity meters. It delivers energy to the escapement via a lightweight DC motor, which spins continually, its rotation geared down through a worm wheel to a hairspring around the axis of the escape wheel. The motor is set to run slightly fast, and as it moves a pair of fine contacts inside the movement gradually move apart; when they separate, the motor coasts until the clock catches up: the motor then resumes once the contacts close. This system allows the clock to be extremely efficient with power, running on only o.5mA.
This is the only known example of an O’Keenan one-second wall clock; it is badged ‘CDC’ and is in a relatively ornate case featuring a pilastered top, inlaid wood and a brass ornamental keyhole. It is conceivable it may have been intended for the public area of an institution such as a bank, department store or factory.
