Mr. Roberts's great success with the self-acting mule led to his being often appealed to for help in the mechanics of manufacturing. In 1826, the year after his patent was taken out, he was sent for to Mulhouse, in Alsace, to design and arrange the machine establishment of Andre Koechlin and Co.; and in that and the two subsequent years he fairly set the works a-going, instructing the workmen in the manufacture of spinning-machinery, and thus contributing largely to the success of the French cotton manufacture. In 1832 he patented his invention of the Radial Arm for "winding on" in the self-acting mule, now in general use; and in future years he took out sundry patents for roving, slubbing, spinning, and doubling cotton and other fibrous materials; and for weaving, beetling, and mangling fabrics of various sorts. A considerable branch of business carried on by the firm of Sharp, Roberts, and Co. was the manufacture of iron billiard-tables, which were constructed with almost perfect truth by means of Mr. Roberts's planing-machine, and became a large article of export. But a much more important and remunerative department was the manufacture of locomotives, which was begun by the firm shortly after the opening of the Liverpool and Manchester Railway had marked this as one of the chief branches of future mechanical engineering. Mr. Roberts adroitly seized the opportunity presented by this new field of invention and enterprise, and devoted himself for a time to the careful study of the locomotive and its powers. As early as the year 1829 we find him presenting to the Manchester Mechanics' Institute a machine exhibiting the nature of friction upon railroads, in solution of the problem then under discussion in the scientific journals. In the following year he patented an arrangement for communicating power to both driving-wheels of the locomotive, at all times in the exact proportions required when turning to the right or left,--an arrangement which has since been adopted in many road locomotives and agricultural engines. In the same patent will be found embodied his invention of the steam-brake, which was also a favourite idea of George Stephenson, since elaborated by Mr. MacConnell of the London and North-Western Railway. In 1834, Sharp, Roberts, and Co. began the manufacture of locomotives on a large scale; and the compactness of their engines, the excellence of their workmanship, and the numerous original improvements introduced in them, speedily secured for the engines of the Atlas firm a high reputation and a very large demand. Among Mr. Roberts's improvements may be mentioned his method of manufacturing the crank axle, of welding the rim and tyres of the wheels, and his arrangement and form of the wrought-iron framing and axle-guards. His system of templets and gauges, by means of which every part of an engine or tender corresponded with that of every other engine or tender of the same