PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION. 



471 



distance from the edge, and the latter rising from beh)w tl)rough the button 

 hole. The straight needle has three ej'es, the curved one two. 



These needles work together, the curved being placed at such an angle 

 as to give a loop to the straight in the downward motion of the latter, and 

 to receive one as it ascends. This forms a double interlocking stitch, pre- 

 senting, when the threads are loosely drawn, a double ptarl as it is term- 

 ed, or two rows of knots, as shown in fig. I. The positions of these pearls 

 npon the edge of the cloth are changed at will by varying the tension of 

 the threads, and may be drawn together so as to present but one row of 

 knots. (Fig. 2.) 



Figure 1. Figure 2. 



Although the stitch and mode of laying it were successfully perfected, the 

 inventors now experienced the greatest difficulty in the way of final success. 

 Many machines for stiching button holes had theretofore been attempted. 

 Years and fortunes had been expended in inventions, but although several 

 ingenious machines were produced, the^' were of no practical value, as all 

 inventors seemed to start with the idea that, as in other sewing machines, 

 the needle or needles must remain stationary, and the garment in which 

 the hole was to he worked, moved around it. This effectually prevented 

 complete success, as it was found impossible to turn the cloth with suffi- 

 cient accuracy and rapidity to insure a straight-sewed edge and perfect 

 eyelet at the end of the hole. 



Aware of these failures, the Messrs. House determined, if possible, to re- 

 verse this njotion and hold the cloth still while the needles moved around 

 the edge of the button hole. 



After several attempts they succeeded in producing the present machine, 

 which was first patented on the Ilth of November, 1862, and afterward 

 became the property of the Wheeler & Wilson Sewing Machine Manufac- 

 turing Company. 



The movements by which the result is obtained are beautifully exact. 



They consist of a screw and gripe-wheel, 

 the former of which, attached by a nut 

 to a bracket in the lower case, drives 

 the stitching mechanism along the 

 straight side or edge of the button hole, 

 and the latter enclosed in a wheel turns the same ar(.)und the eyelet or 

 rounded end of the hole. (See figure I.) 



The needles, threads, &c., are mounted on a travelling rotating disk, and 

 both work from below through a slot or opening in a cloth plate. Upon 

 this plate the garment in which button holes are to be stitched is fastened 

 by a clamp, the needles projecting through a button hole. 



In working the straight side of a hole, the screw carries the disk upon 

 which the stitching mechanism is mounted at stated intervals along the 



