PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION. 457 



separate patent, is very short and straight, and is made self-adjusting by 

 means of a groove in its shank and a spline or small steel rib in the hole 

 for it in the needle bar, D, so that it is impossible to insert the needle in any 

 but the right position; the needles being of one length, when they are push- 

 ed to the bottom of the hole and secured by the nut, E, are sure to be ad- 

 justed properly. The tension on the thread is produced by passing it be- 

 tween two polished glass washers, P, fitted on a screw spindle pressed to- 

 gether by a spring, the pressure of which is regulated by turning the 

 screw. It is very easily understood and managed, and cannot corrode, or 

 get out of order otherwise. The revolving looper, B, by which the stitch 

 is formed, has also been very much improved, and is now a beautiful ex- 

 sample of simplicity and perfection in operation. 



The hemmer fig. 3, and the feller fig. 4, which are also patented, are quite 

 simple, and at the same time very effective; and it is claimed that they 

 have this marked superiority over any others, in that they turn the hem or 

 fell to the under side, so that the stitch is on the right side of the workj 

 They are also self-adjusting, and it is not possible to set them wrong; they 

 do their work with great perfection and celerity. By means of a groove, 

 a, in the cloth pressor, (see perspective view,) I raid can be sewed on cloth 

 in any desired pattern. The length of the stitch is regulated by the lever, 

 G, and the cloth pressor thrown off the plate by the cam, H. The stitch 

 made by this machine is new and peculiar; it is called the " twisted loop 

 stitch," and requires but one thread to form it, producing thereby a beaU' 

 tiful, elastic and durable s(;am, which is so strong that a piece not half an 

 inch long cut from it cannot be pulled apart. It also has this advantage — 

 that it can be easily removed if desired, by unlooping the end of the thread 

 and pulling on it. As a family sewing machine it possesses many advan- 

 tages; among which its extreme simplicity and quietness and ease of ope- 

 ration are not the least noticeable. 



The same subject was selected for the next discussion, after which the 

 Association adjourned. 



American Institute Polytechnic Association, ) 



October 8, 1863. ] 

 Chairman, S. D. Tillman, Esq.; Secretarj^, J. W. Chambers. 

 At the commencement of the miscellaneous business, Mr. Bull read the 

 following extracts from an article in the Atlantic Monthly for October, 1864: 



The United States Armory at Springfield. 



The United States Armory at Springfield, Massachusetts, is the largest, 

 best appointed, and altogether the most productive establishment for the 

 manufacture of small arms i)i the world — those belonging to the Austrian 

 Government, at Vienna, and to the British, at Enfield, being greatly inferior 

 both in size and appointments; while the quality of the guns manufactured 

 here is very superior to that at either of those important establishments. 

 Indeed, the Springfield rifled musket is justly regarded as the most perfect 

 arm of its kind which has ever been produced. To attain this desirable 

 point of excellence has required the skill and perseverance of the best 

 Eiechanical minds which this country — always prolific in inventive genius 



