An attempt toward obtaining invariable measures of length, capacity, and weight, from the mensuration of time / [John Whitehurst].

  • John Whitehurst
Date:
1792?]
Catalogue details

Licence: Public Domain Mark

Credit: An attempt toward obtaining invariable measures of length, capacity, and weight, from the mensuration of time / [John Whitehurst]. Source: Wellcome Collection.

    40/86 (page 12)
    [ .* ] The plate A, Fig. 2, is fixed to the frame as be- fore directed. The two pillars being inferted at P P for that purpofe : and the apparatus L is immovably fixed to the frame by means of feveral fcrews. L, Fig. 5, reprefents a tranfverfe fedlion of the plate A, to which the moveable point of fufpenfion M is connected, and in which the pendulum wire is in- clofed ; whence fome idea may be formed of its labi- lity. d d, fig. 4, reprefents the crutch through which the wire pafles; ft the counterpoife to the pallats; b the moveable ball whereby their center of gravity may be adjufted, to render the vibration equal to thofe of each pendulum, viz. 42 and 84 per minute. Fig. 3 reprefents the form of the pillars which are inferted into the plate A, and pafs between the planks to connedt the apparatus to the frame. Fig. 6 reprefents the inftrument adapted to draw the two lines on the ruler when the pendulums are adjufted : but more of this hereafter. Plate III reprefents not only the dial plate, but alfo the front plate of the movement frame; the in- dexes