Undercutting as a Means and as an End; its Use and Abuse—"Built-up" Work—"Planted" Work—"Pierced" Work.
By undercutting is meant the cutting away of the solid portions of projections in such a manner as to make them invisible, thus throwing the carved surface work into more complete relief by detaching it from the background. This device has often been carried so far, where the projection was sufficient, that entire groups of figures and foliage have been practically detached from the background, like pieces of separate sculpture carved all round. This desire for completeness of relief was more or less a departure from the orthodox aims of the carvers' craft, and led ultimately to what is known as "built-up" work—that is to say, work in which the projecting parts were composed of many different pieces of wood, each carved separately, and afterward glued or pinned together to form the composition. Many of the most elaborate carvings by Grinling Gibbons are of this kind; they have a charm of their own, but it is one of quite separate interest, and belongs to a category entirely removed from the art of carving objects in a solid piece of wood. Apart from this distinction, the difficulty of the method requires the most accomplished mechanical skill and a highly trained eye to either carve or compose such work in a way to command respect. I shall therefore dismiss this branch of the subject as being outside of our present limits.
Undercutting, on the other hand, is an expedient distinctly characteristic of solid wood-carving, and some experiments ought to be made by you in designing work in which it can be used. It may be either partial or complete—complete, of course, only up to a point; that is to say, the connection with the background must in every case be not only maintained but visibly demonstrated. Partial undercutting applies to such portions as the sides of leaves, the receding parts of heads, wings, etc., where the wood between the object and its background is cut away on an inward bend, either completing the projecting form, as in the case of a head, or merely to hide the superfluous wood in the case of a leaf. All this presupposes a certain amount of elevation in the relief; indeed, it is only in such cases that the process is necessary or can be carried out. The use of undercutting of this kind is like every other technical process, liable to abuse through too much being made of its effects. Fortunately the time it consumes is a safeguard against any tendency to run riot in this direction. The point at which it should in all cases stop, and that relentlessly, is where it begins to cause a separation between any entire mass of ornament and its background. If portions are thus relieved almost to complete detachment, but visibly reconnect themselves in another place, a certain piquancy is gained which adds charm without destroying character. A curious use is made of undercutting in the bunch of leaves given in Plate XI from a Miserere seat in Winchester Cathedral; it may be said to be completely undercut in so far that the whole bunch is hollowed out under the surface, leaving from 1/4 to 1/2 in. thickness of wood, in which the leaves are carved, so that you may put your finger in at one hole and see it at the bottom of another. The only end all this extra labor seems to have attained is that of changefulness in the shadows of the holes between the leaves, in which one sees dark rims with light at the bottom, a condition which certainly adds a mysterious lightness to the whole mass. It is a very refined and appropriate use of undercutting, but would only be possible where time could be spent to secure a variant of such epicurean delicacy, as all the superfluous wood must be taken out through the spaces between the leaves, and in this case they are not overlarge for that purpose.
Work which has its background entirely cut away, and which is afterward glued or "planted" on a fresh background to save labor, can not be called "undercut"; this method has generally a cheap look, as it is used with the object of saving time and expense. Carving which is treated in this way, but instead of being "planted" close to the background, is fixed at a little distance from it (as is the case with the lace-like designs fitted into the hollow moldings of fifteenth-century choir-screens), is of quite a different order, although even in this case it can not be strictly described as undercut: it is more nearly akin to pierced fretwork. It has, however, all the general effect of undercut work, and is the only possible way of obtaining this effect in wood where a large quantity of such ornament is required. The face of such carving is generally a little convex, while the back is hollowed out to give an equal thickness of section. The ornaments in Figs. 75, 76, and 77 are of this description, and are calculated to give great play of light and shade, and be seen well at a considerable distance.
Undercutting in the strict and more laborious sense must be reserved for occasions where the labor is repaid by the additional charm. It must be considered in the light of a tour de force, which, on account of its cost in the matter of time, should only be used under exceptional circumstances, care being taken to make it clear that it is an exception to the general rule of solid carving on a solid background.
