John Mills



John Joseph Merlin was born in 1735 and was an inventor in the true sense. Merlin's most famous invention is roller skates. He made his unusual skeleton band clock for an exhibition in 1776 and it differs in principle and method of construction to almost any other clock.

The base is an integral part of the clock which has a fusee and spring barrel of conventional design although the fusee has a left hand thread and revolves clock wise instead of anti clockwise as is usual. The centre wheel turns the escape wheel arbor, unusually for clock work, by a worm which is at eight threads to the inch. The centre arbor turns once every hour. The clock has a dead beat escapement and runs for eight days having 16 turns on the fusee.

The clock indicates the time on two separate bands rotating around the centre arbor with hours on one band and minutes on the other. The minute band revolves with the centre arbor and is held to it by a friction bow spring. The hour band is a loose fit on the centre arbor and is indexed by twelve pins that connect with a small detent at the bottom of the band. When the hour is due to change the minute band has one pin on it that engages with a pivoted arm in the front column. The arm also engages with one of the 12 pins in the hour band and advance the hour band one pin, or one hour. All arbors run in jewelled pivots.

There is a conventional dial at the left hand side and a date calendar indicator on the right hand side.

Two “small modifications” were made by builder, John Mills, to the published plans (aren’t those entasis columns?) and the spring was purchased from a supplier. The chemical etching for the bands was done by a commercial engraving firm but the filling and silvering were done by John.

This wonderful clock was photographed at the National Model Engineering and Modelling Exhibition (then at Harrogate) back in 2009.

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