>t>o 



SILK. 



where silks of the best description are manufactured, 

 is performed in the following manner: the cocoons 

 are placed in an oblong copper boiler, a foot and 

 a half in length, and six inches deep; the boiler is 

 supported upon a brick stove, and the water in it- 

 heated by charcoal. The boiler is divided into 

 transverse portions, into each of which, generally, 

 live cocoons are placed. The ends of the filaments 

 are led from the cocoons in the boiler, and guided 

 by passing on hooked wires, so as to be separated 

 from each other, and also made to cross, so that by 

 rubbing on one another, they may be cleaned. 

 The threads then pass through a guide, which 

 moves alternating transversely, from which they 

 pass upon the revolving reel. The reel consists of 

 four arms, which support rails parallel to the axis, 

 and these rails are placed at such a distance from 

 each other, that one turn of the reel winds off one 

 yard in length of the filament. One of the arms 

 of the reel is furnished with a joint, so that it may, 

 as occasion requires, fold down, and, by slackening 

 the coil, allow it to be slipped easily off the reel. 

 Motion is given to the machine by a crank on the 

 axis of the reel, or by a revolving pully connected 

 to it and the traverse by bands and wheel work. 

 The water in the copper is kept nearly at the 

 boiling point, to soften the gummy matter of the 

 cocoons. Four or more threads being led from the 

 copper together, and uniting by the gum, form one 

 thread. When any one of the filaments breaks, a 

 union must be made by laying on another, the gum 

 being sufficient to cause the adhesion without tying. 

 Great care is required in reeling, however simple 

 the process may appear. The filament grows 

 smaller as the cocoon is unwound, so much so that 

 when a cocoon is half unwound, the filament is 

 only half the thickness of what it was at the 

 beginning. A woman, with the assistance of a 

 girl, can, on an average, wind off one pound of silk 

 per day, when the silk is of the finest description; 

 but if of the coarsest, six or eight times that quan- 

 tity. The cocoons which have been pierced by 

 the worm, are treated in a different manner. After 

 being boiled and placed in a basin, they are wound 

 upon a distaff; the silk thus obtained is called 

 fliuret, and from its superior quality sells at a 

 much higher price than that procured by the former 

 process. By the latter method, a good spinner will 

 not produce more than one ounce of thread in a 

 day. The factory in which the reeling is carried 

 on is called a filature, and the silk thread produced 

 in the manner we have described is called raw 

 silk. 



Raw silk is not adapted for the purpose of the 

 fabrication of cloth; and it must undergo the 

 operation of throwing ere it passes to the hand of 

 the weaver. By the throwing operation, the silk 

 is produced in either of the three forms of singles, 

 tram, or organzine. 



In the throwing mill the first operation is the 

 winding of the silk upon bobbins, which is effected 

 by a winding engine, similar in its construction to 

 those employed in the cotton manufacture for 

 winding off the hank. The bobbins are made to 

 wind off the silk from the beginning to the end of 

 the process at a uniform speed, by being made to 

 rest upon cylinders of metal, revolving uniformly by 

 the geering of the machine, the rollers being turned 

 by the friction arising from their weight pressing 

 upon the cylinders. 



This being done, and the silk assorted as to its 

 fineness, it is carried to the throwing mill. This 



machine will be easily understood by a reference <o 

 our description of the bobbin and tiy frame, under 

 the article Cotton Manufacture. But in the 

 throwing mill the process is somewhat different 

 from the cotton spinning machine. On consulting 

 the article above referred to, it will be seen that 

 the thread or rove (according as the apparatus we 

 are speaking of is used as a fly frame or throstle), 

 is wound upon the bobbin ; but in the silk throwing 

 machine the process is reversed, the thread being 

 unwound from the bobbin, twisted by the revolu- 

 tion of the flyer, and wound upon a reel. In the 

 passage of the silk threads from the bobbins to the 

 reel there is no drawing, or in other words, then- 

 are no rollers between which the threads pass, so 

 as to be drawn out, as in the water frame of Sir 

 Richard Arkwright. The silk is only twisted. 

 The twist of the silk thread may be altered ac- 

 cording to circumstances, by varying the relative 

 velocities of the reel and flyer. The silk intended 

 for organzine receives the greatest number of twists 

 in the inch. The silk thus prepared is called 

 singles. 



The next operation is to bring two or more of 

 these threads twisted upon one bobbin. This is 

 done in a throwing machine, like that we have 

 spoken of above, and the silk thus spun is called 

 tram silk, commonly used for the woof of the silk 

 weaver. In its formation, the twists have been 

 given all in one direction, and it is accordingly ot 

 the nature of twine, or the strands of which a rope 

 is composed. 



Two or more of these threads of tram silk 

 twisted in the throwing mill together, constitutes 

 organzine, a species of silk thread employed for 

 warps. There is, however, this distinction between 

 organzine and tram silk, that whereas the threads 

 of the latter are all twisted in one direction, 

 forming individual strands, like twine, the threads 

 of the former are twisted in an opposite direction, 

 like rope, that is, if in a thread of organzine each 

 strand be twisted to the right, then the collected 

 threads are spun or twisted to the left, as in the 

 formation of a rope or cable. 



In the state to which we have now brought the 

 silk, it is said to be hard, in consequence of the 

 gum, which, however, is separated by boiling. The 

 boiling process requires great care, and in conse- 

 quence of ignorance or negligence often destroys 

 the silk. It is much more safe to separate the gum 

 by steam. The hanks of raw silk are not boiled 

 but soaked in a tub of tepid soap water. 



The throwing machine has been greatly improved 

 both as to accuracy and produce, by assimilating it 

 to the cotton throstle. The speed of the spindles 

 of the machines in this country, till very lately, and 

 still on the continent, was not above 1200 revolu- 

 tions hi the minute; but now, from the exertions of 

 Messrs Fairbairn, Lillie and Ritson, the speed has 

 been raised to 4500. 



Another form of process in the manufacture of 

 silk thread has been lately made the subject of let- 

 ters patent, and brought into successful operation. 

 The use of this process, or combination of proces- 

 ses, is to spin into thread the waste of the throw- 

 ing mill. 



The waste from the throwing mill is made to 

 pass through an endless heckle of a construction 

 that will be understood from what follows. The 

 ends of the silk waste are placed between the 

 edges of two boards, which are then firmly screwed 

 together, so that the silk hangs out like a fleece; a 



