It is rare to find an unconverted Arnold escapement; it is even rarer to find one with such unusual compensation. In a regular compensation curb all parts are made fixed and are installed as such; they cannot be adjusted, and they either work correctly or do not. In this watch, the compensation can be adjusted by changing the point at which it acts on the regulator pin: the closer to the center, the greater the compensation, the farther away, the lesser the compensation. It seems that the present compensation was Arnold's answer to Earnshaw's sugar- tong compensation. John Roger Arnold (1769-1843) The son of eminent British horologist John Arnold, he was apprenticed in Paris to A.-L. Breguet in 1792. He was admitted as a member of the Clockmaker's Company in 1796, and became Master in 1817. After the death of his father, John Roger remained in business on his own until 1830, maintaining the reputation gained by his father as one of the foremost makers of his time. In 1830 he moved to 84 Strand and entered into a partnership agreement for ten years with E. J. Dent, during which period business flourished. Much experimental work was carried out during this period, particularly on the influence of magnetism on chronometers. In 1840 Dent left Arnold, setting up next door at 82 Strand. Arnold continued business on his own but died three years later, in February 1843. Immediately, Charles Frodsham purchased the business. Under the name of Arnold and Frodsham, the company flourished until 1858.