Dent’s new Compensation Balance for Chronometers. 93 
Fig. 6, isa Perspective view of a balance Fig. 6. 
a F 
sation of the balances shown in figures 4 and 
5, if in excess, the staples must be shortened 
or thickened; and the reverse must be done, if in defect : the p primary compensa- 
tion is iifjasiod: by thes the height of the weight v, on the screw w, according 
to the usual practic 
My patent further consists in the introduction of a remontoire- 
escapement into a chronometer or other portable timekeeper. The 
remontoire-spring being wound up at regular intervals by the 
main-spring through the train of wheels, gives an invariable im- 
pulse to the balance by means of an impulse-escape-wheel. 
The principle of this escapement, now introduced into a chro- 
nometer, may be considered the same as that lately invented by 
G. B. Airy, Esq., Astronomer Royal, who furnished me with 
the drawings from which I recently conistracted the first astro- 
_ homical clock containing his escapement. 
r. Airy having generously given his invention to the public, 
T have adopted those parts of it which were applicable to a chro- 
nometer ; and have succeeded in preserving the ordinary detach- 
ed ascapemént, (which has so long and so deservedly maintained 
its undisputed preéminence,) and uniting in conjunction with it 
such adaptations as to convert it into a remontoire-escapement for 
a chronometer 
The result of this eouibiiiitidn is, that a constant impulse is 
given to the balance by the impulse-escape-wheel, without its re- 
ceiving any lateral pressure from the usual train of wheels ; for 
that of the remontoire-spring can hardly, with justice, tic so 
called. : 
~ London, Nov. 1, 1842. 
