1841.

WALTON

v.

POTTER.

and it will be evident, that, by varying the thickness of the metallic surface, the proper thickness of the caoutchouc will be cut off: a sharp knife, kept occasionally wet with water, and supported on guides, is then pressed with a sawing action against the India rubber or caoutchouc by the operator, at the same time that he forces the India rubber or caoutchouc forward between the guides by turning the roller N, and thus severs or cuts off a piece of the exact thickness required: the pieces thus cut off may be joined together to form fillets or sheets, according to the nature of the card intended to be made, and, when the teeth or dents are set therein, may be nailed to the board in the usual manner, or cemented on it: this apparatus is shewn at figure 4, which represents a side view, and figure 5 an end view of the same: in these figures, L represents the knife, and h h the rests on which it is supported; N N is the block of caoutchouc or India rubber, and none of the layers cut off seen in figure 5; M represents the roller pressed upon the caoutchouc or India rubber N N by weights attached to the small rods m m on each side: in cutting the layers of caoutchouc or India rubber, I have found the operation greatly facilitated by using water and keeping the knife constantly wet: but I would here observe that I lay no claim to the cutting apparatus hereinbefore described, as I have only shewn it as the best method I am at present aware of to effect the purpose. The apparatus for grinding or point- Apparatus for ing the wires forming the cards hereinbefore described, is pointing the represented in figure 1, which is an elevation of a portion of a shaft having a series of cutters or files placed thereon, as will be described hereafter: this shaft must be fixed in suitable bearings, and rotatory motion be communicated thereto from any first mover: CC is the shaft, of any required length, d d d are a number of circular steel rings or discs, having bevelled edges on each face, with grooves or notches in them similar to files, for the purpose of

teeth.

Figure 1.