TILES 997 



The upper cylinder has an iron axis, and is formed of as many rollers as there are 

 threads ; each roller being kept in its place upon the lower one by the guides k, whose 

 vertical slots receive the ends of the axis. 



The yarn delivered by the bobbin I, glides over the rod c, and descends into the 

 trough d e, where it gets wetted ; on emerging, it goes along the bottom of the roller 

 g, turns up so as to pass between it and h, then turns round the top of h, and finally 

 proceeds obliquely downwards, to be wound upon the bobbin m, after traversing the 

 guide-eye n. These guides are fixed to the end of a plate which may be turned up 

 by a hinge-joint at o, to make room for the bobbins to be changed. 



There are three distinct simultaneous movements to be considered in this machine : 

 1, that of the rollers, or rather of the under roller, for the upper one revolves merely 

 by friction ; 2, that of the spindles m, s' ; 3, the up-and-down motion of the bobbins 

 upon the spindles. 



The first of these motions is produced by means of toothed wheels, upon the right 

 hand of the under set of rollers. The second motion, that of the spindles, is effected 

 by the drum z, which extends the whole length of the frame, turning upon the shaft 

 v, and communicating its rotatory movement (derived from the steam-pulley) to the 

 whorl b' of the spindles, by means of the endless band or cord a'. Each of these 

 cords turns four spindles, two -upon each side of the frame. They are kept in a 

 proper state of tension by the weights e', which act tangentially upon the circular 

 arc d , fixed to the extremity of the bell-crank lever e? f g', and draw in a horizontal 

 direction the tension pulleys h, embraced by the cords. The third movement, or the 

 vertical traverse of the bobbins, along the spindles m, takes place as follows : 



The end of one of the under rollers carries a pinion, which takes into a carrier 

 wheel that communicates motion to a pinion upon the extremity of the shaft TO', of the 

 heart-shaped pulley n'. As this excentric revolves, it gives a reciprocating motion to 

 the levers o', o', which oscillate in a vertical plane round the points p', p r . The 

 extremities of these levers on either side act by means of the links tf, upon the arms 

 of the sliding sockets r', and cause the vertical rod s', to slide up and down in guide- 

 holes at t', u', along with the cast-iron step if, which bears the bottom washer of the 

 bobbins. The periphery of the heart-wheel M', is seen to bear upon friction wheels 

 x, x 1 , set in frames adjusted by screws upon the lower end of the bent levers, at such 

 a distance from the point p', as that the traverse of the bobbins may be equal to the 

 length of their barrel. 



By adapting change pinions and their corresponding wheels to the rollers, the 

 delivery of the yarn may be increased or diminished in any degree, so as to vary the 

 degree of twist put into it by the uniform rotation of the drum and spindles. The 

 heart-motion being derived from that of the rollers, will necessarily vary with it. 



Silk thread is commonly twisted in lengths of from 50 to 100 feet, with hand reels, 

 somewhat similar to those employed for making ropes by hand. 



THUYA OCCIDENTAIiIS. A coniferous tree, from which is obtained a 

 yellow body, Thuyin, which is probably identical with Quercitrin. 



TlXiE ORE. (Ziegelerz, Ger.) An earthy variety of red oxide of copper. 



TIKES. Tile-manufacture is a very comprehensive term, embracing the following 

 varieties : Paving bricks or tiles, oven-tiles, foot tiles, plain tiles, pan tiles, hip tiles, 

 ridge tiles, circulars, drain tiles, &c. 



The clay used for making tiles is purer and stronger than that used for making 

 bricks. When the clay is too strong, that is, too adhesive, it is mixed with sand 

 before passing it through the pug-mill. As a usual practice the clay is weathered ; 

 this is effected by spreading it out in layers of about two inches in thickness during 

 the winter, and each layer is allowed the benefit of at least one night's frost before the 

 succeeding layer is put over it. This weathering is sometimes effected by exposing 

 the layers to sunshine, which is said to answer equally well with frost. What this 

 weathering does is by no means clear : it is said ' to open the pores of the clay.' 

 We believe that what really takes place is, that under the influences to which it is 

 exposed, the particles break up into smaller particles, and that we have the clay in a 

 more finely comminuted state. The next process is that of tempering. After the 

 clay has been allowed to ' mellow, or ripen,' in pits, under water, it is passed through 

 the pug mill and well kneaded or tempered. 'It is then slung, that is, cut into slices 

 with a string ; during which process the stones fall out, or are removed by the hand ; 

 it is then ready for the operation of moulding. This may be performed by hand, or- 

 by any one of the many machines which have been devised. 



Fig. 1977 shows Mr. Hunt's machine for making tiles. It consists of two iron 

 cylinders, round which webs or bands of cloth revolve, whereby the clay is pressed 

 into a slab of uniform thickness, without adhering to the cylinders. It is then carried, 

 over a covered wheel, curved on the rim, which gives the tile the semi-cylindrical or 

 other required form ; after which the tiles are polished and finished by passing 



