Old clocks and watches & their makers : being an historical and descriptive account of the different styles of clocks and watches of the past, in England and abroad, to which is added a list of nearly twelve thousand makers (1922)
Britten, F. J. (Frederick James), 1843-1913, Britten, Annie · London : E. & F. N. Spon · leaf 623
Fig. 828.—Tompions Regulator. Fig. 829.—Barrows Regulator. lever and other detached escapements which allowed the balanceto have a larger arc of vibration. To lengthen or shorten the acting length of the spring, Tompion
Clocks and watches · Clock and watch makers
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