Q74 Instrument to measure and register [Ocr. 
wheels or cylinders: the most elevated of these, marked F, is that 
upon which the line J is wound to suspend the float G in the tube 
Hi: upon the extreme end of the axis of the wheel F is a small 
cylinder R to receive the cord d of the balance weight I, which is 
such as so far to balance the weight of the float as tokeep the line 
b always extended : on the opposite end of the axis of the upper 
wheel is fixed a long pinion k of 30 teeth; this gives motion to the 
cylinder K, upon which the shect of paper is wrapped, by means of 
a wheel of 360 teeth. As the wheel and pinion are in the propor- 
tion of twelve to one, it follows that any motion which is given by 
the float line 4 will be communicated to the cylinder K upon the 
scale of an inch to a foot; that is, a rise or fall of one foot in the 
float will produce a motion of an inch in the paper with which this 
cylinder is covered, or one inch of the paper will pass by the 
pencil, which is to mark by the hammer of the clock L. 
This clock is mounted upon four pillars e from the table; fis the 
weight of the clock, and g a small counter-balance, which, being 
pulled down, will draw up the great weight to wind it up, and will 
then serve for eight days; the hour-hand, which is seen in the 
front, is carried immediately by the arbor of the barrel of the clock, 
and shows 24 hours; the circle above this, divided into 10, shows 
the minutes, as it makes its revolution in 10 minutes; and the 
upper circle is for the seconds, 
The disposition of the train of wheel-work, for the clock 
not being at all essential, ‘is not therefore shown in the drawing; 
but any clock-maker to whom the construction is committed will 
be able to make a proper clock from the number of the wheels, 
which are as follows. 
The great wheel on the barrel, which carries the hour-hand, 96 
teeth, revolves in 24 hours. ; 
The centre wheel, pinion, eight leaves, and the centre wheel $4; 
these will revolve in two hours. 
The third wheel, pinion, seven leaves, aad the third wheel 70 - 
teeth; they complete their revolution-in ten minutes ; and the arbor 
carries the minute-hand. 
Lastly, the pinion of the swing-wheel having seven leaves, it 
will revolve in one minute, carrying the second-hand and swing- 
wheel, which having 30 teeth, and acting with two anchor pallets, 
they will suffer the wheel to advance + a tooth at every vibration of 
the pendulum N, which is performed in a second. 
The train must be made rather stronger than usual to enable it to 
carry a greater weight f, in order that the regularity of the motion 
may not be deranged by the resistance of lifting the hammer O 
which makes the marks upon the cylinder K. This hammer is fixed 
upon an arbor extended between the clock plates, and has two arms 
or levers proceeding from it, one to reach the third wheel, and the 
other to the centre wheel. The former wheel, which revolves once 
in ten minutes, has one pin fixed in its circumference, and the latter 
has 12 pins. Now as it turns in two hours, it is plain that one pin 
