We have followed the four main lines of influence from the old shop at Windsor; one, through Lawrence, to Hartford; one, through Howe, to Providence; one, through Stone and later Gridley, at Windsor; and the fourth, through Hartness and the Jones & Lamson Machine Company to Springfield. Another line of influence comes through Charles E. Billings, who learned his trade under Robbins & Lawrence, went to the Colt Armory, and as we have seen elsewhere, founded the Billings & Spencer Company. Like Mr. Hartness, he also has been a president of the American Society of Mechanical Engineers. There are other lines of influence in Ohio, Pennsylvania and elsewhere which we cannot follow out here. CHAPTER XVI THE BROWN & SHARPE MANUFACTURING COMPANY Two companies, both in New England, have been conspicuous for their leadership in tool building and the introduction of precision methods in manufacture. One of them, the Pratt & Whitney Company, we have considered. The other, the Brown & Sharpe Manufacturing Company, of Providence, calls also for special notice. It was founded in 1833 by David Brown and his son Joseph R. Brown.[189] For nearly twenty years its business comprised the making and repairing of clocks, watches and mathematical instruments, in a small shop without power. Its influence was hardly more than local and only fourteen persons were employed in 1853, when Lucian Sharpe was taken into the partnership, and the firm became J. R. Brown & Sharpe.[190] [189] David Brown retired in 1841. For the early history of David and Joseph R. Brown see Van Slyck: “Representative Men of New England.” [190] The writer would acknowledge his indebtedness to Mr. L. D. Burlingame for much of the material in this chapter. The real development of the business had begun a few years before. In 1850 J. R. Brown had invented and built a linear dividing engine which was, so far as is known, the first automatic machine for graduating rules used in the United States. It was fully automatic, adapted to a wide variety of work, and provided with devices for correcting the inaccuracies of the machine as built, and such as might develop on account of wear. Various improvements were made in this machine within the next few years and two more were built, one in 1854 and one in 1859, essentially like it. These three machines are in use today and doing work which meets modern requirements of accuracy. [Illustration: FIGURE 42. JOSEPH R. BROWN]