the Dead Escapement for Clocks. 335 
known, any improvementin the method of executing it, whereby 
the practice is made more exactly to agree with the theory 
than has hitherto been the case, may not be unworthy of notice. 
The principle of the dead-escapement is well known ; the 
motion of the pendulum is maintained by the action of the 
wheel on the inclined planes of the pallets, which occupy a 
portion of the arc of vibration of the pendulum, equal to the 
angle of the pallets ; during the remainder of the vibration, the 
tooth bears on the circular parts, or rests of the pallets, which 
are portions of two circles, concentric with the axis of the 
verge, or centre of motion of the pallets, and consequently there 
ought not to be any recoil in the escapement, if properly exe- 
cuted. Various constructions and shapes of pallets and pallet- 
frames, each supposed to possess some peculiar advantage, 
have, at various periods, been adopted; but the whole have 
been executed with the file. The construction of the dead- 
escapement, of which the following is a description, and which 
I have employed, is, with the exception of the inclined planes 
of the pallets, and forming the frame out of the turned piece 
or pieces, entirely executed in the lathe; and if the parts are 
accurately turned with a slide-rest, must of course possess a 
degree of precision, independent of its other advantages, which 
pallets executed with the file cannot possess. 
Fig. 1, of which Fig. 2. is a section, represents a circular 
brass plate, with a square groove, AB, turned in it. Fig. 3, 
represents a steel ring, of which Fig. 4, is a section, turned 
very exactly of width and thickness to fit perfectly into the 
groove A B, portions of which form the pallets. Fig. 5, repre- 
sents the pallet-frame made out of the circular piece of brass, 
represented Fig. 1, L and M; Figs. 2, 5, and 8, are two 
pieces, fixed with screws to the frame to retain the pallets 
immovably in the grooves. Figs. 6 and 7, represent each a 
pair of pallets, made of part of the steel ring, the one with 
short, the other with long, inclined planes; 1, 2, and 3, 4, are 
the inclined planes of both pair of pallets. Fig. 8, represents 
the pallets placed in the frame, and held firmly in their places 
by the pieces Land M. The preferable mode of making the 
