336 
MR. KATER’S DESCRIPTION OF CAPTAIN RATER’S 
by inclined planes or pallets. At the top of each inclined plane is a projecting de- 
tent, on which the tooth of the scape-wheel rests, after having, by sliding along the 
inclined plane, raised the detent through a space equal to the height of the plane. 
The pendulum, meeting a wire which projects from the arm, forces the detent from 
the tooth which rested upon it, carries the arm before it to a certain height, and is 
pressed by the arm in its descent through a space increased by the height of the in- 
clined plane or pallet, the excess affording the impulse. 
Although my father admitted that this escapement performed admirably, he still 
objected to it, first, because it is dependent upon the train, and consequently a greater 
or less pressure of the tooth of the scape-wheel upon the detent will oppose a corre- 
sponding resistance to the pendulum in unlocking ; and secondly, because the beat 
is scarcely audible. If to remedy this, weight be added to the clock, it will then be 
liable to trip. 
The little success with which attempts to improve the astronomical clock had been 
attended, my father considered might be accounted for by the circumstance, that 
attention had been almost exclusively paid to effecting, by means of superior work- 
manship, a regular transmission of the moving power through the train, instead of 
merely viewing the train as an assemblage of wheel-work for registering the number 
of vibrations made by the pendulum ; whereas, he conceived that the great object was 
to discover a mode of communicating equal impulse to the pendulum through some 
principle, perfect in itself, and not dependent for its success on superior execution. 
In the construction of some chronometers, this idea has been partially kept in view, 
especially in the Remontoir escapements ; and in such escapements the train is em- 
ployed merely to wind up a spring, which is detained in its place by means of a detent. 
This detent being removed by the balance, the spring is again at liberty to act and 
give the impulse. 
The objection, however, to the Remontoir escapement is, that the balance has to 
unlock a detent, and thus the delicacy and freedom of motion of that part, the undis- 
turbed action of which should be as much as possible preserved inviolate, is interfered 
with, and this, my father conceived, was the reason that chronometers with Remon- 
toir escapements proved in some respects less perfect in their performance than 
those of the usual superior construction, in which the impulse is given directly through 
the train. 
The pendulum of the escapement which I am about to describe merely raises a 
weight, and is impelled by that weight through an increased space in its descent; it 
neither unlocks a detent, nor has anything to do with the train ; and as the weight 
raised and the spaces described are constant quantities, this escapement is in the 
strict meaning of the term one of equal impulse. 
I shall now proceed to give the general description of the escapement and its mode 
of action, together with the precautions necessary to be observed in its construction, 
which I have collected from the notes left by my father, and as I wrote many of 
