The earliest recorded weight-driven mechanical clock was built in 1283 in Bedfordshire in England.
有记载的最早的重量驱动机械钟是1283年在英国贝德福德郡建造的。
2
It is weight-driven and at the time he wrote (1987) resident in the Rotunda at Greenwich.
它是重量为主导，在当时他写道：（ 1987 ）居住在中央大厅在格林威治。
3
A quarter of the weight of HB-SIA is accounted for by its lithium-polymer batteries, which will power the four electrically driven propellers during the first test flights.