CARVED AND MOULDED WORKS.

45

combining with the gallic acid of the wood, and forming a natural stain, similar to writing ink. Much of the oak timber of the Royal George that was accidentally sunk at Spithead, in 1782, and which has been recently extricated by Col. Pasley's submarine explosions, is only blackened on its outer surface, and the most so in the neighbourhood of the pieces of iron; the inside of the thick pieces, is in general of nearly its original colour and soundness. Some specimens of cam-wood* have maintained their original beautiful red and orange colours, although the inscription says that they were "washed on shore at Kay Haven, in October 1840, with part of the wreck of the Royal Tar, lost near the Needles twenty years ago, when all the crew perished."

The recent remarks on colour equally apply to the works of statuary, carving and modelling generally: the materials for which are either selected of one uniform colour, or they are so painted. Then only is the full effect of the artist's skill apparent at the first glance; otherwise it frequently happens either that the eye is offended by the interference of the accidental markings, or fails to appreciate the general form or design, without a degree of investigation and effort, that detracts from the gratification which would be otherwise immediately experienced on looking at such carved works.

This leads me to advert to modes sometimes practised to produce the effect of carving: thus, in the Manuel du Tourneurt, a minute description will be found of the mode of making embossed wooden boxes, which are pressed into metallic moulds, engraved with any particular device. The wood is first turned to the appropriate shape, and then forced by a powerful screwpress into the heated mould, (which is made just hot enough to avoid materially discolouring the wood,) it is allowed to remain in that situation until it is cold; this method however only applies to subjects in small relief, and is principally employed on knotty pieces of box-wood and olive wood of irregular curly grain.

The following may be used for bolder designs, more resembling ordinary carving: the fine sawdust of any particular wood it is required to imitate, is mixed with glue or other cementitious matter, and squeezed into metallic moulds, but in the latter case the peculiar characteristic of the wood, namely its fibrous struc* Received from the hands of H. Hardman, Esq. + Second Edition, vol. ii., pp. 441-451.

46

EMBOSSED WORKS, ETC.

ture, is entirely lost, and the eye only views the work as a piece of cement or composition, which might be more efficiently produced from other materials, and afterwards coloured.

Each of these processes partakes rather of the proceeding of the manufacturer than of the amateur; extensive preparations, such as very exact moulds consisting of several parts, and a powerful press, &c., are required,* and the results are so proverbially alike, from being "formed in the same mould," that they lose the interest attached to original works, in the same manner that engravings are less valued than the original paintings from which they are copied.

Another method of working in wood may be noticed, which is at any rate free from the objections recently advanced: I will transcribe its brief description†.

"Raised figures on wood, such as are employed in picture frames and other articles of ornamental cabinet work, are produced by means of carving, or by casting the pattern in Paris plaster or other composition, and cementing or otherwise fixing it on the surface of the wood. The former mode is expensive, the latter is inapplicable on many occasions.

"The invention of Mr. Straker may be used either by itself or in aid of carving; and depends on the fact, that if a depression be made by a blunt instrument on the surface of wood, such depressed part will again rise to its original level by subsequent immersion in water.

"The wood to be ornamented having first been worked out to its proposed shape, is in a state to receive the drawing of the pattern; this being put in, a blunt steel tool, or burnisher, or die, is to be applied successively to all those parts of the pattern intended to be in relief, and at the same time is to be driven very cautiously, without breaking the grain of the wood, till the depth of the depression is equal to the subsequent prominence of the figures. The ground is then to be reduced by planing or filing to the level of the depressed part; after which, the piece of wood being placed in water, either hot or cold, the parts previously depressed will rise to their former height, and will thus form an embossed pattern, which may be finished by the usual operations of carving.

* See the Section on Tortoiseshell.

+ Trans. Soc. of Arts, vol. xlii., p. 52.

CHAPTER V.

PERMANENCE OF FORM, AND COMBINATION OF THE WOODS.

SECT. I.-SHRINKING AND WARPING.

THE permanence of the form and dimensions of the woods requires particular consideration, even more than their comparative degrees of ornament, especially as concerns those works which consist of various parts, for unless they are combined with a due regard to the strength of the pieces in different directions, and to the manner and degree to which they are likely to be influenced by the atmosphere, the works will split or warp, and may probably be rendered entirely useless.

The piece of dried wood is materially smaller than in its first or wet state, and as it is at all times liable to re-absorb moisture from a damp atmosphere, and to give it off to a dry one, even after having been thoroughly seasoned, the alterations of size again occur, although in a less degree.

The change in the direction of the length of the fibres is in general very inconsiderable *. It is so little in those of straight grain, that a rod split out of clean fir or deal is sometimes employed as the pendulum of a clock, for which use it is only inferior to some of the compensating pendulums: whereas a piece of the same wood taken diametrically out of the center of a tree, or the crossway of the grain, forms an excellent hygrometer, and indicates by its change of length the degree of moisture of

* Good box-wood and lance-wood are approved by the Tithe Commissioners for the verified scales to be employed in laying down the plans for the recent Parliamentary survey, as being next in accuracy to those of metal; whereas those of ivory are entirely rejected by them, owing to their material variation in length under hygrometrical influence. See their printed papers.

Mr. Fincham says he has found a remarkable variation in the New Zealand pine the Kourie or Cowrie, corrupted into Cowdie, which expands so much as to cause the strips constituting the inside mouldings of ships to expand and buckle, probably from the comparative moisture of our atmosphere and Colonel Lloyd says he found the teak timbers used by him in constructing a large room in the Mauritius, to have shrunk three quarters of an inch in thirty-eight feet, although this wood is by many considered to shrink sideways least of all others.

48

SHRINKING AND SPLITTING.

the atmosphere. The important difference in the general circumstances of the woods, in the two directions of the grain, I propose to notice, first as regards the purposes of turning, and afterwards those of joinery work, which will render it necessary to revert to the wood in its original, or unseasoned state.

The turner commonly employs the transverse section of the wood, and we may suppose the annual rings then exhibited, to consist of circular rows of fibres of uniform size, each of which, for the sake of explanation, I will suppose to be the one hundredth of an inch in diameter.

When the log of green wood is exposed to a dry atmosphere, the outer fibres contract both at the sides and ends, whereas those within, are in a measure shielded from its immediate effect, and nearly retain their original dimensions. Supposing each of the outside fibres to be reduced to the one hundred and tenth, or the one hundred and twentieth of an inch, as the external series can no longer fill out the original extent of the annual ring, the same as they did before they were dried; they divide, not singly, but into groups, as the unyielding center, or the incompressible mass within the arch, causes the parts of which the latter is composed to separate, and the divisions occur in preference at the natural indentations of the margin, which appear to indicate the places where the splits are likely to com

mence,

Fig. 12.

The ends being the most exposed to the air are the first attacked, and there the splits are principally radial, with occa

AS REGARDS TURNED WORKS.

49

sional diversions concentric with the layers of fibres, as in fig. 12, and on the side of the log, the splits become gradually extended in the direction of its length. The air penetrates the cracks, and extends both cause and effect, and an exposure of a few weeks, days, or even one day, to a hot dry atmosphere, will sometimes spoil the entire log, and the more rapidly the harder the wood, from its less general penetrability to the air. This effect is in part stayed by covering the ends of the wood with grease, wax, glue, paper, &c., to defend them, but the best plan is to transfer the pieces very gradually from the one atmosphere to the other, to expose them equally to the air at all parts, and to avoid the influence of the sun, hot drying winds, &c.

The horizontal slice or block of the entire tree, is the most proper for the works of the lathe, as it is presented by nature the most nearly prepared to our hand, and its appearance, strength, grain, shrinking, &c., are the most uniform. The annual rings, if any be visible, are, as in fig. 13, concentric with Figs. 13.

14.

15.

the object, the fibres around the circumference are alike, and the contraction occurs without causing any sensible departure from the circular form. Although thin transverse slices are necessarily weak from the inconsiderable length of the fibres of which they are composed, (equal only in length to the thickness of the plate,) they are strengthened in the generality of turned works by the margin, such as we find in the rim of a snuff-box, &c., which supports the bottom like the hoop of a drum or tambarine.

The entire circular section is therefore most appropriate for turning, next to it the quartering (fig. 14,) should be chosen, but its appearance is less favourable; and a worse effect happens as the shrinking causes a sensible departure from the circle, the contraction being invariably greater upon the circular arcs of fibres, than the radial lines or medullary rays. If such works