.S7A' U'lI.LIAM SIEMENS, F.R.S. 69 



Plate '2, is a side elevation ; Fig. 8, Plate 3, an end elevation 

 partly sectional ; and Fig. f>, Plate 4, a plan partly sectional. 



The machine consists of two grooved pressing rollers A and B, 

 Fig*, l, 2, and 8, Plates 2 and 8, and of two cutting or shearing 

 rollers CC, all of which are of hardened steel, and are shown 

 enlarged to half full size in the section, Fig. 4, Plate 8. On 

 each side of the groove in the pressing rollers A and B is a small 

 cylindrical portion, as shown enlarged to double full size in Figs. 

 9 and 10, Plate 5, of a breadth equal or nearly so to the thick- 

 ness of the intended coating to be applied ; but these cylindrical 

 sides must be slightly rounded off' towards the groove and sharp 

 on the outer edge, as shown at DD. The cutting rollers C are so 

 placed on each side of the grooved rollers that in turning round 

 their cutting edge crosses the edges of the grooved rollers a little 

 before the centre line of the machine, as shown double full size in 

 Figs. 7 and 9, Plate 5, at a point where the distance between the 

 edges of the grooved rollers is about equal to half the thickness of 

 one of the strips of india-rubber used. The axis of the cutting 

 rollers is slightly inclined to the axis of the grooved rollers, as 

 shown in the end elevation, Fig. 3, and plan, Fig. 5 ; so that 

 being pressed against the latter by means of set screws, they only 

 touch hard at the shearing point, as seen in Figs. 9 and 10, Plate 

 5. The wire to be covered and the two strips of india-rubber 

 for covering it are guided into the machine by suitable guides E, 

 Figs. 1 and 5. The two strips in closing upon the wire are drawn 

 tight over it by the inner edges of the grooved rollers A and B ; 

 and being caught between the closing cylindrical portions of the 

 grooved rollers, are compressed to one-fourth their original thick- 

 ness, the material being forced outwards from the middle ; the 

 cutting rollers C then suddenly intersect them, as in Fig. 9, Plate 

 5, cutting off' the superfluous breadth of strips, and at the same 

 time preventing further escape of the material towards the sides. 

 As the edges of the grooved rollers continue to close upon one 

 another, the material remaining between them can only escape 

 inwards, by which means the two fresh-cut edges are brought one 

 upon the other under a heavy rolling pressure, from which they 

 glide inwards towards the groove, as in Fig. 10, and in so doing 

 form a complete and permanent joint, Fig. 11. In order to effect 

 several successive coatings, a train of machines is provided, as 



