SILK MANUFACTURE 



789 



the silk districts of France the throwing-mills are generally small, not many of them 

 turning off more than 1,000 pounds of organzine per annum, and not involving 5.000/. 

 of capital. The average price of throwing organzine in that country, where the 

 throwster is not answerable for loss, is 7 francs ; of throwing trame, from 4 fr. to 5 fr. 

 (per kilogramme ?) Where the throwster is accountable for loss, the price is from 

 10 fr. to 11 fr. for organzine, and from 6 to 7 for trame. In Italy, throwing adds 

 3s. 9d. to the price of raw silk, upon an average. It seems probable, from the perfec- 

 tion and speed of the silk-throwing machinery in this country, as about to be described, 

 that the cost of converting a pound of raw silk either into organzine or trame must be 

 considerably under any of the above sums. 



The first process to which the silk is subjected, is winding the skeins, as imported, 

 off upon bobbins. The mechanism which effects this winding off and on, is techni- 

 cally called the engine, or swift. The bobbins to which the silk is transferred, are 

 wooden cylinders, of such thickness as may not injure the silk by sudden flexure, and 

 which may also receive a great length of thread without having their diameter 

 materially increased, or their surface velocity changed. Fig. 1767 is an end view of 



1767 



the silk-throwiug machine, or engine, in which the two large hexagonal reels, called 

 swifts, are seen in section, as well as the table between them, to which the bobbins 

 and impelling mechanism are attached. The skeins are put upon these reels, from 

 which the silk is gradually unwound by the traction of the revolving bobbins. One 

 principal object of attention, is to distribute the thread over the length of the bobbin- 

 cylinder in a spiral or oblique direction, so that the end of the slender semi-transparent 

 thread may be readily found when it breaks. As the bobbins revolve with uniform 

 velocity, they would soon wind on too fast, were their diameters so small at first as to 

 become greatly thicker when they are filled. They are therefore made large, are 

 not covered thick, but are frequently changed. The motion is communicated to that 

 end of the engine shown in the figure. 



The wooden table A, shown here in cross section, is sometimes of great length, 

 extending 20 feet, or more, according to the size of the apartment. Upon this the 

 skeins are laid out. It is supported by the two strong slanting legs B, B, to which the 

 bearings of the light reels c are made fast. These reels are called swifts, apparently 

 by the same etymological casuistry as lucus a non lucendo, for they turn with reluctant 

 and irregular slowness ; yet they do their work much quicker than any of the old 

 apparatus, and in this respect may deserve their name. At every eighth or tenth leg 

 there is a projecting horizontal piece D, which carries at its end another horizontal 

 bar a, called the knee-rail, at right angles to the former. This protects the slender 

 reels or swifts from the knees of the operatives. 



These swifts have a strong wooden shaft b, with an iron axis passing longitudinally 



