T H R 



401 



T H 



in exile. After the Syracusans had thus delivered them- 

 selves of the tyrant, they granted to his mercenaries free 

 departure, and also assisted other Greek towns in Sicily in 

 recovering their freedom. (Diodorus Sic., xi. 67 and 68.) 



THRASYMEXE LAKE (Trasimenus Lacus, in the best 

 Latin MSS. ; in Greek writers, } X/^vi; Tfavvplvij, or 6pa- 

 mfiivij), the antient name of the Lago di Perugia in Italy. 

 It was in Etruria, and was the scene of the third defeat of 

 the Romans by Hannibal after he had crossed the Alps. 

 rHANXiBAi..] " The lake itself is fully described under 

 '-.KroiA. 



THRAULITE. Hisingerite. Hydrated Silicate of Iron. 

 Occurs in roundish nodules. Fracture uneven or imper- 

 fect conchoidal. Structure curved, foliated. Brittle. 

 Splendent. Nearly opaque. Lustre vitreo-resinous. Colour 

 brownish-black. 



Gives out water when heated in a glass tube ; imper- 

 fectly fused by the blowpipe, and is, after heating, attracted 

 by the magnet. 



It, occurs at Riddarhyttan in Westmanland (1) and at 

 Bodenmais in Bavaria (2), accompanying iron pyrites. 



Analysis by 



(1) HUinger. (2) Kobell. 



Silica . . 36-30 31-28 



Peroxide of Iron . 44-39 50-86 



Water 20-70 10-12 



101-39 101-26 



THREAD (French, Fil ; German, Zicirn ; Dutch, Garen ; 

 Italian, R-/K ; Spanish, Hilo, Torzal ; Russian, Nitki}, a 

 small line formed by twisting together fibres of vegetable 

 or animal substances, as flax, cotton, or silk. Sewing- 

 thread, and the various kinds of thread used in the manu- 

 facture of bobbin-net, lace, and some other kinds of textile 

 fabric, consist of two or more yarns, or simple spun threads, 

 firmly united together by twisting, just as a rope-strand 

 consists of several yarns or distinct cylinders of hemp. 

 [RopK. vol. xx., p. 154 ; SPINNING, vol. xxii., p. 34!).] 



In a paper on the manufactures of Paisley, printed in 

 the Appendix to Anderson's ' History of Commerce' (.edi- 

 tion of I~s7-!)), it is stated that ' the manufacture of thread 

 \va-i first attempted in this country by Mrs. Millar, of Bal- 

 garran, in 1722, on having received some information and 

 machinery from Holland.' Her example was speedily fol- 

 lowed by several families in Paisley, where the manufac- 

 ture soon became of considerable importance. The first 

 manufacturers imitated the kind called Nuns' or ounce 

 thread, which was made up in hanks of forty threads each, 

 reeled upon reels a yard in circumference ; but when 

 the profits of the manufacture were diminished by com- 

 petition, it was injured by the surreptitious practices of 

 some of the manufacturers, who reduced the number of 

 threads in each hank from forty to thirty, and when this 

 became notorious in the market, put but twenty-eight 

 threads in the hank, or reduced the diameter of their reels, 

 and consequently the length of the threads. These frauds 

 were carried to such an 'extent that it became necessary, 

 in 1~8, to pass an act of parliament requiring all manu- 

 facturers of this description of thread to use uniform stand- 

 ard reels of thirty-six inches in circumference, and to put 

 thirty threads or rounds of the reel in each hank. From 

 the statement above referred to, it appears that the num- 

 ber of machines employed at Paisley in twining thread, in 

 1784, was not less than 120 ; and that the number employed 

 in the thread manufacture in the whole of Scotland at that 

 time was at least 500, of which about 200 were engaged in 

 the production of the different species of ounce threads. 

 These consumed upon an average 2400 spindles of yarn 

 each, or 480,000 in the whole ; and these spindles, valued 

 at 4*. Gil. each, when manufactured into thread, amounted 

 to 108,000/. The 300 machines employed in making other 

 kinds of thread consumed upon an average 2000 spindles 

 each, or 600,000 spindles in the whole, which, estimated 

 . !)-/. each when manufactured, amounted to 112.000/. 

 Thus the total annual value of the thread manufactured in 

 land about 1784 was 220,000/. ; and it is stated that 

 the manufacture gave employment in its various operations, 

 from the ginning of the" flax to the finishing of the 

 thread, to upwards of 20,000 women, besides 4000 or 5000 

 men. 



The manufacture of thread from fibres of cotton-wool, for 

 sewing and other purposes, is one of the many important 

 dep;t: lintish industry called into exercise by the 



;'. C., No. 1538. 



improvements effected by Arkwright and his successors m 

 spinning-machinery, and forms a considerable branch of 

 business both in Manchester and in Scotland, for exporta- 

 tion as well as for home consumption. 



The operation of combining yams of cotton or linen into 

 thread is performed by a mauilme called a doubling and 

 twisting frame, somewhat resembling the throstle of the 

 cotton-spinner. Engravings of this machine, with a minute 

 description, are given in Dr. Ure's ' Cotton Manufacture of 

 Great Britain,' vol. ii., pp. 226-234, and ' Dictionary of 

 Arts,' pp. 1239-1241, from which authorities the following 

 account is derived. Along the centre of the machine is 

 an elevated creel or frame-work, which supports two parallel 

 rows of cops or bobbins of yarn, one row towards each side 

 of the macnine. The cops or bobbins arc placed vertically, 

 or nearly so, and the lower ends of their axes rest in oiled 

 steps or hollows, while the upper ends are supported by 

 wire eyes, so that they may revolve with facility. The 

 number of cops or bobbins of yarn is twice as great as that 

 of the twisting spindles when the thread is to consist of 

 two yarns, three times as great for thread formed of three 

 yarns, &c. ; and the yarn with which they are charged is 

 frequently gassed, or passed quickly through a series of 

 coal-gas flames, to singe off' any loose downy fibres, before 

 it is taken to the doubling and twisting frame. From the 

 cops the yarns are conducted over horizontal glass rods, 

 which are fixed parallel with the creel, and thence down- 

 wards into troughs filled with water or very thin starch- 

 paste, which by moistening the yarns facilitates the sub- 

 sequent process of twisting. To ensure the equal moisten 

 ing of the yarns they are, while being drawn through the 

 troughs, made to pass either under a glass rod, or through 

 eyes which may, if necessary, be lifted out. of the trough 

 without wetting the fingers, by means of upright stems 

 provided for that purpose. The wetting-troughs and other 

 apparatus are alike on each side of the machine ; but in 

 further tracing the progress of the thread we shall confine 

 our attention to one side, and to the apparatus necessary 

 for producing one thread, although a great number of such 

 trains of apparatus are combined in one frame, and set in 

 motion by one train of impelling machinery. After being 

 wetted the yarns pass over the rounded edge of the trough, 

 which is covered with flannel for the purpose of absorbing 

 the superfluous moisture ; and thence under and partly 

 around an iron roller, which is made to revolve with any 

 required velocity by a train of wheel-work. Upon this 

 roller rests another, of box-wood, which revolves solely by 

 contact with the iron roller, its axis playing in vertical 

 slots. In passing under the iron roller, then between it 

 and the wooden roller, and finally over the latter, the yarns 

 required to form the thread are brought together and 

 slightly compressed ; but although thus prepared for a 

 more intimate union, they are not yet twisted together. 

 The action of the winding and twisting apparatus may be 

 illustrated by a diagram, in which none but the essential 

 parts are shown. In this figure a a represents the un- 

 twisted thread, or rather the united yarns which are to 

 form the thread, and b is a fixed eyelet through which 

 they are conducted to the flyer c, which is mounted upon 

 and revolves with a long vertical spindle set in motion by 

 a whorl or pulley and strap at d. e is the bobbin upon 

 which the finished thread is wound by the revolution of 

 the flyer, which also gives to it any predetermined degree 

 of twist. The spindle passes freely through a hole in the 



centre of this bobbin, which rests upon a bar called the 

 copping-rail, the transverse section of which is indicated 



VOL. XXIV. 3 F 



