SEWING MACHINE 359 SEWING MACHINE 1, which thereupon was released and drawn tight, a chain stitch was thus formed, and the cloth being moved for- ward the length of a stitch, the process was repeated and continued. Between 1832 and 1834, Walter Hunt, a New York mechanician, invented and sold several sewing machines which made a practical lock stitch. He, however, ne- glected to apply for a patent. The invention of the eye-pointed needle by Newton & Archibald, patented in 1841, and applied by them to the stitching and tamboring of the back of gloves, formed the most important step in the progress of developing the sewing machine, and in no essential principle did their machine differ from the single-thread machines now in use. In 1844 an invention by John Fisher was patented jointly with James Gibbons, in which a shuttle and needle were used for producing a lock stitch, and by a different combination the patent covered the production of what subse- quently was known as the Grover & Baker, or knotted stitch.^ Elias Howe's invention was patented in the United States by himself, and in England by William Thomas in 1846. Howe, after several years' labor and study, worked out the idea of his sewing machine with- out any guidance from or knowledge of what had been previously accomplished; and he moreover secured such effective combinations of parts as made the Howe machine in reality the acknowledged par- ent of all the forms since introduced. His patent-right for Great Britain was sold for $1,250 to Mr. Thomas, in whose employment Mr. Howe worked for about two years. On returning to the United States in 1849, Howe found that notwith- standing his patent right, several indi- viduals had made, exhibited, and used sewing machines, though not a single machine had yet been made in the United States under his patent. He had, there- fore, to face the task of vindicating his rights. It was not till the end of 1850 that the manufacture of his machine ac- tually began, and it was 1854 before a decision in his favor against I. M. Singer was obtained. The modifications, improvements, and additions made to the sewing machine since its introduction are innumerable. It has now been adapted to produce al- most all kinds of stitching which can be done by the hand; and every variety of work required on garments. The leading classes of machines are: (1) Single- thread machines, (2) machines with two or more threads, and (3) overhead or glove-stitch machines. Single-thread Machines. — The stitch made by the ordinary form of single thread machine is precisely what is known as the crochet stitch, and when the thread is broken at any point the whole work readily undoes. Ordinary single-thread machines, unless for limited applications, such as glove embroidery, are passing out of general use. It is different, however, from the Wilcox & Gibbs single-thread machine, in which a revolving double hook or looper is employed which gives each loop a twist and produces thereby the twisted chain stitch, combining a solid fastening with great elasticity and smoothness. Two-thread Machines. — Of these ma- chines two subdivisions may be recognized — the lock stitch, and the knotted or double chain stitch, commonly called the Grover & Baker machines. Of these, the lock stitch machines are by far the most common, and for general purposes are in almost universal use. For producing the lock stitch there are two forms of apparatus: (1) the reciprocating shuttle which carries a thread through the loop made by the needle, and (2) the lenticu- lar spool or thread case over which the loop is passed by a revolving hook. Of the first kind — shuttle machines — the Howe, the Singer, the Wanzer, and others are familiar forms; the second, or spool and hook appliance, is a peculiarity of the Wheeler & Wilson alone. The needle was originally fixed at the end of a vi- brating arm, and, describing the arc of a circle, it required to be curved. Singer first introduced the straight needle car- ried by a slide, and it now is in general use. Next to the invention of the eye- pointed needle the designing of an efficient feed motion was the most important im- provement made in the sewing machine. Singer introduced what is called the wheel feed, but the plan now adopted is one of the many ingenious and beautiful mechanical devices introduced by A. B. Wilson, of Wheeler & Wilson. It is called the four-motion feed, and consists of a serrated plate to which a forward, down, backward, and upward motion is com- municated, the forward and backward motion being varied according to the length of stitch. The tension of the thread in the shuttle is maintained by a small nipping spring which presses against the thread. In the Wheeler & Wilson machine the use of the shuttle is entirely avoided, and the lock stitch is formed by carrying the loop from the up- per thread over and around the under thread, which is contained within a small lenticular spool, which fits snugly but free in a recess in the side of the revolv- ing hook. This exceedingly ingenious de- vice, together with the four-motion feed above alluded to, place Mr. Wilson, their inventor, in the front rank of improvers of the sewing machine. The Wheeler &