In connection with the development of the sewing machine the name of A. B. Wilson stands next in rank to that of Howe. Wilson invented the rotary hook carrying a bobbin, which took the place of the reciprocating shuttle. This was patented by him June 15, 1852, No. 9,041, and is shown in Fig. 145. He also invented the far more important improvement of the four-motion feed, which is a characteristic feature of nearly all practical family sewing machines. This four-motion feed was pooled in the early sewing machine combination with the Bachelder and other patents, and earned for its promotors a far greater pecuniary return than the original Howe sewing machine itself. Estimates place this profit high in the millions. The four-motion feed was patented December 19, 1854, No. 12,116, and it is a comparatively simple affair. Divested of its operating mechanism, it consists simply of a little metal bar serrated with forwardly projecting saw teeth on its upper surface, to which bar, by means of an operating cam, a motion in four directions in the path of a rectangle is given. The serrated bar first rises through a slot in the table, then moves horizontally to advance the cloth, then drops below the table, and finally moves back again horizontally below the table to its starting point. Upon these two important features--the rotating hook patented by Wilson in 1852, and the four-motion feed, patented in 1854--a large and important business was built. In this business Mr. Nathaniel Wheeler was associated with Mr. Wilson, and the well-known Wheeler & Wilson machines are the result of their enterprise and ingenuity. [Illustration: FIG. 146.--ORIGINAL SINGER SEWING MACHINE.]