Dating french clocks
If your grandfather clock has a brass dial, it was probably made in the period between 16, and most likely between 17. Most of them only had one hand, because the average person had no need of knowing the time to the nearest minute, and with a bit of experience you can tell the time to the nearest five minutes on one of these early clocks.
By 1730 the vast majority of grandfather clocks had two hands, for the hours and minutes.
From 1730 longcase clocks ceased being made in London, the clockmakers followed the demands of fashion, and made bracket, or shelf clocks.
Provincial clockmakers, many trained in London, made large numbers of longcase clocks from 1700 right through to 1880, when imports of cheap German and American wall and mantle clocks put an end to the making of longcase clocks altogether.
This feature started to appear C1760, and continued afterwards on good quality work.
Around the same period, with a slightly larger dial and a wooden hood to keep the dust out of the clock movement.Another date clue I have noticed during clock repairs is that any screws in an early movement (1680 to 1750) have square heads.