The Charnley Forest stone is generally preferred for the first stage or for striking off the wiry edge of the blade. The Turkey oilstone is sometimes used for the same purpose. The Green hone or Welsh hone, which is harder than the Charnley Forest, and generally in smaller pieces, is occasionally used for razors, and is by some preferred to Charnley Forest for finishing pen and pocket knives, and especially for setting surgeons' instruments.

The yellow German hone, particularly the slabs from the lower strata known as old rock, is greatly preferred to all the above for the principal office in setting razors, as it cuts more slowly, smoothly, and softly, than any of them. The Iron stone or slabs of the hematite iron ore, are occasionally used for giving the final edge, it consists principally of oxide of iron, and chemically resembles crocus, but that it is in a compact, instead of a disentegrated form. The iron stone is however so very hard that it appears to act more as a burnisher than a hone, and renders the edge almost too smooth, so that when at all used, the razor is in general only passed once or at most twice on each side along the iron stone.

Taking the razor from the last stage of its manufacture described at page 1051, it is to be observed that as the glazers and polishers revolve away from, and not towards the edge, they always leave a thin filmy edge, which as the first step towards setting, is struck off on a Charnley Forest stone. The blade is grasped in the right hand by its tang, and near to the cutting part, and is placed square across the one end of the stone but tilted about ten or twenty degrees, and is then swept forward along the stone, edge foremost in a circular arc, so as to act on the entire edge; each side in general receives only one stroke, and this produces a comparatively obtuse edge measuring from forty to sixty degrees. Should this fail to remove the wiry edge, the blade is placed perpendicularly upon, and drawn with a little pressure across, a strip of horn, (generally a spoiled razor handle,) which is fixed down to the bench, the friction of the horn against the edge generally suffices entirely to remove the wiry film, otherwise the blade is struck once more on each side along the stone. Should the film of steel be left on the stone, it is removed before another blade is applied.

One object in the striking off, is to avoid the necessity for so far wearing down the back of the razor, as to give it the appearance of an old one that has been repeatedly set, and it is also especially required in wide blades ground on large stones, as the wiry film is then very difficult to remove otherwise.

The next and principal part of the setting is accomplished almost invariably on the German hone. The razor is held as before, but it is now placed quite flat down, or so as to touch on the back and edge. Some prefer a long sweeping stroke backwards and forwards, others prefer small circular or elliptical strokes, and others a short zig zag movement, but all gradually work from heel to point, or draw the razor forward so as to act on all parts alike, and most persons lift the razor endways towards the conclusion, allowing its point still to rest on the hone, with the view of sharpening the circular end of the blade. The choice of these methods seems to be principally a question of individual habit, and to be nearly immaterial, provided the entire edge is acted on alike, and that at very short intervals the razor is turned over so as to whet it upon its opposite sides alternately, but it is general to conclude the process by sweeping the razor edge foremost, once on each side steadily along the hone, as if in shaving off a thin slice of the hone, this lessens the disposition to the wire edge.

The line of policy is just to continue this secondary process, until the new facets constituting the wedge of seventeen to twenty degrees, exactly meet at the extremity of the more obtuse angle given by the striking off, and which if mathematically done, would prevent the formation of the wiry film, which is one of the most troublesome obstacles in the process.

Should the film nevertheless arise, it is to be removed by passing the blade occasionally across the slip of horn, and continuing the whetting for shorter periods on each side, some persons indeed suffer the film if very minute to be abraded on the razor strop, but which latter unless very cautiously used is a very mischievous instrument. It is of course to be understood that the hone is not given up, until at any rate the notches are no longer perceptible, when the blade is drawn across the thumb or finger nail, which detects them more faithfully than the slip of horn, and that when viewed edgeways, the edge is merely discovered as the meeting of the two sides of the blade, and not from possessing itself any visible thickness or width.

As before observed, the blade is by some persons passed once on each side along the iron stone, but this practice is by no means common, and may, according to the questionable doctrine advanced by some cutlers, spoil the blade by rendering it too smooth, or too free from the saw-like teeth, but which it would appear can hardly be the case, unless it also increase the angle of the edge, or render it less acute and keen.

When the edge of the razor admits of being drawn smoothly across the horn, and the edge is not distinguishable by the eye, the hone may be considered to have fulfilled its purpose, and the razor is slightly stropped, but in this case, as the edge of the blade becomes somewhat embedded in the leather, it would cut if moved forwards as in setting, and therefore the razor is always stropped backwards, and usually from heel to point.

Disregarding the high sounding names and praises bestowed on various razor strops, it may be added that within moderate limits, they are the better the harder their surfaces, and the less they are supplied with abrasive matter. As when they possess the opposite qualities of softness and superabundance of dressing, or that they are used in excess, they rapidly round the edge of the razor, and change its edge from the well-defined angle of seventeen or twenty degrees produced by the stone, to twice that angle or more, and entirely unfit it for use.

Perhaps for the razor strop a fine smooth surface of calf skin, with the grained or hair side outwards, is best, it should be pasted or glued down flat on a slip of wood, and for the dressing almost any extremely fine powder may be used, such as impal-pably fine emery, crocus, natural and artificial specular iron ore, black lead, or the charcoal of wheat straw; each of these two latter act as abrasives in consequence of containing a minute portion of silex. Combinations of these and other fine powders, mixed with a little grease and wax, have been with more or less of mystery applied to the razor strop. The choice appears nearly immaterial, provided the powders are exceedingly fine, and they are but sparingly used.

One side of the strop is generally charged with composition; on the other side the leather is left in its natural state, and the finishing stroke is in general given on the plain side.

It is of great importance that all razor strops be kept scrupulously clean, and with which view they are provided with sheaths, which should be marked so as to prevent the composition being accidentally carried over to the clean side of the instrument. The strop should be always employed in the most sparing manner, so as rather to wipe than rub the razor; many, indeed, never strop the razor after use, but simply wipe it dry on clean wash leather, a silk handkerchief, or a soft towel, and only employ the strop before using the razor. A good mode was suggested to preserve the edges of surgical instruments from rusting when laid by, namely, the drawing them lightly through a tallow candle; this leaves a minute quantity of grease on the edge, which defends them from the air, and becomes deposited on the strop before the blade is used.

When a razor, from continued use and stropping, has become dull, it mostly arises from the edge having been rounded and thickened as explained by the diagram, figs. 1037 and 1038; in this case the setting, if attempted by the amateur, may with advantage be only so far pursued as barely to remove the rounded part. On close inspection it will be seen the part of the facet towards the back is first touched by the hone, the effect of which is seen by the less polished surface it leaves; and if the setting be only continued until the bright rounded part is all but removed when examined with a magnifier, no wire will be formed, and the blade will be again brought within the province of the razor strop. The razor, after having been repeatedly set, becomes so wide in the bevil or facet, as to require to be re-ground, to thin it away to the first state, as the blade should always be so thin as to be sensibly pliant at the extreme edge, when pressed flat on the thumb nail and slightly tilted; but the re-grinding should be done with a proper regard to the relative width of the back of the blade, and the preservation of its proper temper.