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8Other kinds of winter-dials are made, which are called Anaporica. They are constructed as follows. With the aid of the analemma the hours are marked by brazen rods on their face, beginning from the centre, whereon circles are drawn, shewing the limits of the months. Behind these rods a wheel is placed, on which are measured and painted the heavens and the zodiac with the figures of the twelve celestial signs, by drawing lines from the centre, which mark the greater and smaller spaces of each sign. On the back part of the middle of the wheel is fixed a revolving axis, round which a pliable brass chain is coiled, at one of whose ends a phellos or tympanum hangs, which is raised by the water, and at the other end a counterpoise of sand equal to the weight of the phellos.
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