Curb Pins
The two brass pins that stand on either side of the hairspring near its stud attachment, and are attached to the regulator. They effect the time of the vibration of the balance according as they are shifted by means of the regulator to or from the point of attachment of the spring. Some authors advise timing in positions by the curb pins. This should never be attempted. The regulator should always stand as near the center of the index as possible. The curb pins should never be far from the stud and should be just wide enough apart to let the spring move between them and no more. Instead of disturbing the curb pins when timing in positions, add to or take from the weight of the balance. See Balance Screw Washers.
CUSIN, CHARLES. A watch manufacturer of Autun, Burgundy, who in consequence of the great persecutions which protestants had to endure, went and settled in Geneva in 1587, where, it is claimed, he was the first to establish the watch trade.
CUSTER, JACOB D. The third maker of American watches, Jacob D. Custer, was born in Montgomery County, Pa., in 1809. In 1831 he went to Norristown, Pa., and began the began the manufacture of "Grandfather" clocks. In 1840 he began the first of a series of twelve watches. The writer has in his possession one of these watches, which is numbered 5 and bears the date February 4, 1843. It is a three-quarter plate, lever escapement, and about 14 size. It has a fuzee evidently of English make, as is also the dial. The balance bridge is made of steel and is countersunk into the plate so that it is flush with the surface of the upper plate. The rest of the movement was undoubtedly made by Custer, including the case, which is of silver and of the old English type of boxed cases. The gilding is extremely thin. In 1842 Prof Bache, of the U.S. Coast Survey asked him to make an estimate on clocks to propel lights in the government light houses. His estimate was $200, and he subsequently furnished several hundred of them. He had little or no educational advantages, and never learned a trade, and his sole knowledge of mechanics was acquired by associating with those who learned a mechanical trade and the knowledge gained by years of experience and experiment. He built several large clocks, one of which may still be seen in the Norristown Court House. He died in 1879.