The edge of the cutter then slides into the material.

The reason why the sliding cut is easier, is partly because the angle of the bevel with the wood is reduced by holding the tool obliquely, and partly because even the sharpest cutting edge is notched with very fine teeth all along its edge so that in the sliding cut it acts like a saw.

In an auger-bit, both methods of cutting take place at once.

The scoring nib cuts with a sliding cut, while the cutting lip is thrust directly into the wood.
The chisel and the knife, one with the edge on the end, and the other with the edge on the side, are the original forms of all modern cutting tools.
The _chisel_ was at first only a chipped stone, then it came to be a ground stone, later it was made of bronze, and still later of iron, and now it is made of steel.

In its early form it is known by paleontologists as a celt, and at first had no handle, but later developed into the ax and adze for chopping and hewing, and the chisel for cuts made by driving and paring.