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TIME RECORDING CYLINDER
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cylinder to be divided by eight lines, drawn parallel to its axis at equal distances from each other, and that the cylinder makes one revolu-
Fig. 25.— Original chronograph of Thomas Young. a, cylinder rotating on vertical axis; b, falling weight acting as motive power; c d, small halls for regulating by centrifugal action the velocity of the cylinder; e, marker recording a line on the cylinder.
tion in one second, the distance between two of the lines will represent the one-eighth of a second, and any movement drawing a curve on the cylinder between the two lines must have
