The octagon wall clock with a lever movement and an 8in. Dial with brass bezel became popular c. 1850 as a timepiece for travelling by sea or rail. The drop octagon, with pendulum movements, striking and silent, installed, is believed to have been introduced by Chauncey Jerome for the London Great Exhibition of 1851. The case design was a modified, abbreviated English Act of Parliament type. The usual dial size was 12in. The earliest models had a veneered octagon top with a projecting compartment at the base and a glass-paneled door revealing the pendulum. Frequently, carved pieces were mounted flanking the door and extending on each side of the base octagon section. This style of timepiece was available as an eight-day striker and was occasionally furnished with an alarm. It was the forerunner of what became known in North America as the 'schoolhouse' clock, manufactured in millions until c. 1930.