On the Cork Equatorial Telescope, kc. 357 
The action is as follows :— 
Supposing the shaft A to be revolving exactly 1 per minute, 
and the pendulum to be vibrating exactly 60 per minute, and that 
there are 30 teeth in scape-wheel, it is evident that the Remon- 
toire arm, and therefore the weights W and w, will vibrate 
backwards and forwards the same distance each second, and 
that the mean position of all will be the same each second. Under 
these circumstances, the weight w will be alternately 0°5 second 
in contact with disc Q,and 0°5 second out of contact, and the 
uniform motion clock is rated ev se, just so much fast that the 
resting of the weight w for 0°5 second in each second will bring 
the rate right. 
Now, suppose an error of acceleration to arise in uniform 
motion clock, the mean position of remontoire arm will rise; 
therefore w will fall, and, instead of rubbing in contact with Q 
for 0°5 second, it will rub for 0°6 or 0:7 second according to the 
extent of the error. This will tend to check the rate, and this 
check will continue till the relative position of the uniform motion 
shaft and of the intermittent or scape-shaft becomes as it was 
when clock was going correctly. 
If a retardation occur, the reverse effect will take place, and the 
weight w will rub for only 0:4 or 0°3 second instead of 0°5 until 
the error be corrected. 
So far as described, I do not claim any particular novelty, as I 
believe that most of this arrangement im principle has been tried 
before, the failure that resulted being owing to the fact that it 
was found impossible to prevent the pendulum being influenced 
by the difference of force on the pallets under varying circum- 
stances, the pendulum being in the former case driven by the 
scapement, not by electricity, as in this case. 
I believe I have completely got rid of this difficulty by— 
Ist. Making the pallets (as they are not required to drive the 
pendulum) of such form that the teeth of scape-wheel impinge 
upon them nearly at the angle of repose; and 
2nd. By driving the pendulum by electric current from 
another clock—thus virtually rendering the pendulum, not a 
pendulum at all, but a lever, worked backward and forward by 
electricity, and not subject to alteration in its rate by slightly 
varying force on the pallets. 
An arrangement is also attached (but not shown in figure to 
