Edmund Arthur Engler, Popular Science Monthly (1883)
“ The primary standard time-keeper of England is a sidereal clock kept in the basement of the Royal Observatory, Greenwich. This clock is of the best construction, and is, moreover, provided with the most approved apparatus for compensation and correction. Experience has shown that the best results are obtained when the connection between the driving-weight and the pendulum of a clock is as slight as possible. This has been accomplished in the Greenwich clock by the use of an elegant escapement, the details of which are shown in Fig. ”
