Quadrant

Two almost identical clinometers to measure the maximum inclination of a rolling ship. Both are made of brass, mounted on a wooden backplate with the center of the arc at the top. The scale on the arc runs from 0° to 45° to each side. The outer edge of the arc is toothed, each side in the opposite direction. The two pointers have pallets against the back, which engage in the teeth: this allows them to move only outward along the arc. The pallets can be released by hand to return the pointers to 0°. Due to a small interruption in the pallet edge, the pointers cannot land in each other's eighth of the arc. The teeth of one quadrant (a) divide the arc into quarter degrees, which on the second (b) are half degrees. The pointers on the first quadrant (a) run with small rollers over the protractor. If the ship rolled, each pointer would swing out to the side where the ship leaned and indicate the maximum inclination. [combined description]