All About Inventions and Discoveries
The Romance of modern scientific and mechanical Achievements

362 Ali About Inventions taken to secure the utmost protection which the law allowed. The unassuming cabinet-maker was A. B. Wilson, and the outstanding feature of his machine was the mechanism for moving the work forward automatic- ally and accurately after each stitch had been formed. The movement became known as the “ four-motion feed” or “drop feed,” and it constitutes the greatest improvement which has been made in connection with sewing machines since Saint demonstrated by his drawings for the first time that mechanical sewing was possible. Indeed, every sewing machine worthy of the name to-day incorporates this feature. Upon the cloth plate, beside the point where the needle passes to penetrate the fabric, are one or two tiny serrated and moving surfaces. When a stitch has been formed these teeth rise a fraction of an inch to grip the surface of the material. Then it is moved forward the predetermined distance. This consti- tutes the second motion. The third motion is the descent of the teeth to release the fabric, followed immediately by the fourth motion, which is to move backwards preparatory to rising to grip the material once more. By the introduction of this feature Wilson rendered the movement of the material not only automatic, whereas hitherto it demanded to be moved by hand, but made the distance or move- ment of the material after each stitch positive and accurate. The labour involved in sewing by machine was appreciably decreased, inasmuch as by this means one merely had to guide the work. Needless to say, this novel mechanism met with the success which it deserved, and enabled the erstwhile journey-