CHAPTER IX.

ON THE CAUSES OF DECAY IN FURNITURE, WOOD CARVINGS, ETC., AND THE MEANS OF PREVENTING AND REMEDYING THE EFFECT OF SUCH DECAY.

Although trunks and boxes are of themselves of little importance, they derive great consequence from the valuable deposits of written papers, deeds, books, &c., which they frequently contain, that are subject to destruction from timber-destroying insects. It is well known that the smell of Russian leather, which arises from an essential oil, is a preservative of books. Leather or woods impregnated with petroleum, or with oil of coal-tar (which has a smell not much dissimilar) would be productive of the same effect, because known to be peculiarly obnoxious to insects: these oils are, however, very inflammable.

At all times beech-wood is exposed to the attacks of beetles, and it cannot be used, even for household furniture, without being impregnated with some kind of oil or varnish, as a defence against these insects--a very curious fact, for the growing trees are remarkably free from the attacks of wood-devouring insects. Larch being solid, and its juices hot, pungent, and bitter, is rarely affected with the larvæ of insects.

Mr. Westwood, Hope Professor of Zoology, Oxford, says: “The insects which in this country are found to be the most injurious from their habit of burrowing into the wood of furniture, belong to three species of beetles, of small size, and cylindrical in form (the better to enable them to work their way through the burrows in the wood), belonging to the family _Ptinidæ_, and known under the systematic names of _Ptilinus pectinicornis_, _Anobium striatum_, and _Anobium tessellatum_.

“In the perfect state, the insects of the genus _Anobium_ are well known under the name of the “deathwatch,” as these insects produce the ticking noise occasionally heard in old houses. It is also the _Anobium striatum_ which is so injurious in libraries; the grub burrowing through entire volumes, and feeding upon the paper, and especially the _pasted_ backs of the books.

“The destruction of these insects, when enclosed in articles of furniture, is by no means easy, although with care much mischief might be prevented. The saturation of the wood with some obnoxious fluid previous to its being used up in the manufacture of objects of value would be beneficial.

“A strong infusion of colocynth and quassia, spirits of turpentine, expressed juice of green walnuts, and pyroligneous acid, have all been proposed. In hot climates the ravages of the _Anobium_ on books have been prevented by washing their backs with a fluid compound of corrosive sublimate (ten grains) and four ounces of alcohol, and the paste used in the book covers is there also mixed with alcohol.”

Sir H. Davy and Professor Faraday hesitated to employ corrosive sublimate as a means of preventing the ravages of the bookworm in Earl Spencer’s library, at Althorp, not feeling certain as to whether the quantity of mercury used would affect the health of the inhabitants. Amongst all the combinations of mercury, perhaps the bi-chloride, or corrosive sublimate, is the most terrible poison. It should be remembered that there are two chlorides of mercury--one the proto-chloride, ordinarily known as calomel; the other, bi-chloride, ordinarily known as corrosive sublimate; the respective compositions of which are as follows:

------------------------------------------------+---------------------- | Parts by Weight. Calomel, and Corrosive Sublimate. +-----------+---------- | Chlorine. | Mercury. ------------------------------------------------+-----------+---------- Calomel, or proto-chloride of mercury | 36 | 200 Corrosive sublimate, or bi-chloride of mercury | 72 | 200 ------------------------------------------------+-----------+----------

Hence the ratio of chlorine in these two chlorides is as one to two.

Botanists have long used a solution of corrosive sublimate in alcohol, known by the name of Smith’s solution, to preserve the specimens in their herbaria from the aggressions of insects.

The Rev. J. Wood, writes:[34] “I know to my cost sundry Kaffir articles being absolutely riddled with the burrows of these tiny beetles (_Anobium striatum_), and not to be handled without pouring out a shower of yellow dust, caused by the ravages of the larva. The most complete wreck which they made was that of a New Guinea bow, which was channelled from end to end by them, and in many places they had left scarcely anything but a very thin shell of wood.

“In such cases I have but one remedy, viz. injecting into the holes spirits of wine in which corrosive sublimate has been dissolved. This is not so tedious a business as it may seem to be, as the spirit will often find its way from one hole to another, so that if half a dozen holes be judiciously selected, the poison will penetrate the whole piece of wood, kill all the insect inhabitants, and render it for ever impervious to their attack. The above-mentioned bow cost me but little trouble. I first shook out the greater part of the yellow powder, and then, placing the bow perpendicularly, injected the spirit into several holes at the upper end. The effect was magical. The little beetles came out of the holes in all directions, and not one survived the touch of the poisoned spirit; many of them, indeed, dying before they could force themselves completely out of the holes. The ticking of the deathwatch is, in fact, the call of the _anobium_ to its mate, and as the insect is always found in old woods, it is very evident why the deathwatch is always heard in old houses. There is, by the way, a species of cockroach which acts in a similar manner, and generally disports itself on board ship, where the sailors know it by the name of ‘Drummer.’”

The earliest account[35] we can find of the use of corrosive sublimate to destroy worms in woods is a few words mentioned, in 1705, by M. Homberg, French Academian. In that year he stated that a person of position in Provence, France, knew how to make a parquet floor which would resist the worm, viz. by soaking the wood in water in which corrosive sublimate had been mixed, and this process he had always found to be very successful.

Herr Temmnick preserved his books from the _anobium_ by dipping them in a solution of quassia. Except on a small scale, however, the saturation of furniture seems scarcely practicable. Fumigation seems, however, to be more available. For small objects, the practice adopted at the Bodleian Library, Oxford, on Professor Westwood’s recommendation, appears good, viz. to enclose a number of volumes in a box, shutting quite close, and placing a small quantity of benzine in a saucer at the bottom of the case. The same plan might be adopted with small ornamental wood-works, enclosing them in glass cases shut as nearly air-tight as possible.

The Report of the Commission appointed by the Department of Science and Art to inquire into the causes of decay in wood carvings, and the means of preventing and remedying the effects of such decay, which was published in 1864, states that the action of the worm in wood carvings may be arrested, and the worm itself destroyed, by vaporization, more especially by the vapour of benzine; and that, after the worm has been destroyed, further attacks from it can be prevented by treating the carved work with a solution of chloride of mercury, either in methylated spirits of wine, or parchment size, according to the surface character of the carving or woodwork; the strength of the solution in each case being 60 grains of the chloride of mercury to a pint of fluid, whether spirits of wine or parchment size. The carving or woodwork should be placed in a box, made as air-tight as possible, but with means of renewing the benzine placed in saucers from time to time as it evaporates without opening the lid of the box. Gilded carved work and panels on which pictures have been painted, and which have been attacked by the worm, can only be treated by applying the fumes of the benzine to the back of the pictures or gilded carved work: there is no reason to suppose that the vapour of the benzine would influence either the gilding of the one or the colours of the other.

The process should always be carried out during the spring and early summer months, according to the state of the temperature and the observations of those in charge of the carved or other work, as to the action of the worm, which is manifested by the fine dust falling from the worm-holes, crevices, &c.

Mr. Henry Crace was engaged in 1855 to restore some of the wood carvings in the Mercers’ Hall, London, which had been perfectly honeycombed by a small brown beetle about the size of a pin’s head. The carvings being first washed, a number of holes were bored in the back by a gimlet, and also into every projecting piece of fruit and leaves on the face. The whole was then placed in a long trough, 15 inches deep, and covered with a solution, prepared in the following manner:--16 gallons of linseed oil, with 2 lbs. of litharge finely ground, 1 lb. of camphor, and 2 lbs. of red lead, were boiled, for six hours, being well stirred the whole time; 6 lbs. of bees’-wax was then dissolved in a gallon of spirits of turpentine, and the whole mixed while warm thoroughly together.

In this solution the carving remained for twenty-four hours. When taken out the face was kept downwards, that the oil in the holes might soak down to the face of the carving. The dust was allowed to remain to form a substance for the future support of the wood, and as it became saturated with the oil it increased in bulk, and rendered the carving perfectly solid.

No insect has since been found to touch these carvings, as they could not subsist on this composition.

In 1855 the carvings of Grinling Gibbons, at Belton House, were in such a condition as to render it absolutely necessary that something should be done to prevent their complete destruction. To this end they were placed in the hands of Mr. W. G. Rogers, who undertook to experiment upon their restoration. This gentleman reported that the first step he took was to have the various pieces photographed, as a means of recording the position of each detail of the ornamentation, &c. The whole of the works were in a serious state of decay, portions being completely honeycombed by the worm. In order to destroy or prevent any future development of the insect within the wood, Mr. Rogers caused the whole to be saturated with a strong solution of corrosive sublimate (bi-chloride of mercury) in water. The colour of the wood, however, suffered so seriously by the action of the mercury that it was found necessary to adopt some means of restoring the original tint. (It gives a dark colour to the wood, which is caused by the metal contained in the sublimate.) This was effected by ammonia in the first instance, and subsequently by a slight treatment with muriatic acid. After this the interior of the wood was injected with vegetable gum and gelatine, in order to fill up the worm-holes and strengthen the fabric of the carvings. A varnish of resin, dissolved in spirits of wine, was afterwards spread on the surface, and then the dismembered pieces were put together in conformity with the photographs taken, as records, prior to the work of restoration having been commenced.

In order to ascertain the present condition of these carvings, seven years after the operations detailed had been completed Mr. Rogers communicated with the Hon. Edward Cust, one of the trustees of the Earl Brownlow who desired him to communicate with the clerk of the works at Belton. Mr. G. A. Lowe. Mr. Lowe, in writing to Mr. Rogers, informed him that “there is never any appearance of worm dust from the very beautiful carving by Gibbons since you preserved it some years back.”

Mr. Rogers stated, at a meeting of the Royal Institute of British Architects, a few years since, that similar carvings at Ditton Park, Cashiobury, and Trinity College, Oxford, are in a state of decay, the surface or skin, in some instances, being, covered with a deceptive white vegetable bloom, which assists in completing the work of destruction.

Painting hastens the work of destruction. In the library of Trinity College, Cambridge, some of the finest carved work at some former time was thickly painted over, preventing the escape of the insects within, which were compelled to feed on the last bit of woody fibre, leaving nothing but the _skeleton_ of what it once was. At Cashiobury, where can be seen room after room of the finest of Gibbons’ work, all this charming carving (about thirty years ago) was covered over and loaded with a thick brown paint and heavy varnish, destroying all the delicate feathering of the birds and veining of the leafage, the repairs being done in plaster or a composition. Flowers, each about the size of an orange, were thus left with nothing but a skin of dust, with just enough fibre left to save them from collapsing in the handling. All the glorious work of Gibbons in the chapel of Trinity College, Oxford, was some years since covered with a dirty, undrying oil.

We dislike painters who paint carvings as much as the servant who applied to Mrs. H---- (wife of the celebrated landscape painter) for an “appointment” as cook, and having ascertained that the master of the house was a “painter,” remarked, “I cannot take the situation, ma’am, as I have never lived in a _tradesman’s family_.”

It is a difficult process to remove paint from carvings, as it is not possible to scour and wash it off in the ordinary way: it must be eaten off by an alkaline solution.

With reference to the restoration of carvings which have not been painted, but only blackened by time, they must be scoured by the careful hand of an experienced man.

Mr. Penrose, the present architect to the Dean and Chapter of St. Paul’s, a short time ago examined the beautiful carvings in St. Paul’s Cathedral, and he was able to state that they have not hitherto been attacked by worms. “Some portions had been broken by violence, but the state of preservation was marvellous.” Mr. Rogers also observed that “he was greatly and agreeably surprised--contrary to his expectations--to find the carvings in St. Paul’s in so good a state of preservation, and so free from the attacks of insects; but such was undoubtedly the fact. How it was so he was not able to say.” Why was this? Well, Sir Christopher Wren was a wise man, and when he erected St. Paul’s Cathedral, he engaged an experienced mason to remain at the Portland stone quarries, whose duty was to select every block of stone for the Cathedral, and when it arrived in London it was placed _on its natural bed_. The good results of this precaution can now be seen in the good preservation of the stone at the present time. If he was so careful of the stone for the walls, no doubt equal care was taken in the selection of the wood for carvings. Besides, the _instructions_[36] to the commissioners for rebuilding St. Paul’s were drawn up with a view of preventing decay. The following is an extract from these instructions:

“And to call to your Aid and Assistance such skilful Artists, Officers, and Workmen as ye shall think fit, and to appoint each of them his several Charge and Employment; to minister to such Artists and Officers, and to all and every other person and persons to be imployed in the said service, to whom you shall think meet, such Oath or Oatlis for the due performance of their several Duties, Employments, Offices, Charges and Trusts to them or any of them to be committed as shall by you be thought reasonable and convenient; and out of such Money as shall be received for this Work, to allow to them, and every of them, such Salaries, Wages, and Rewards respectively as to you shall seem fitting and proportionable to their Employment and the Service they shall do.”[37]

Sir Christopher Wren was descended from Dutch ancestors: he was building for a Dutch king, and we therefore perceive the reason why so much Dutch wainscot was introduced by him into England.

It seems a great pity that the beautiful carvings of Grinling Gibbons and others should be allowed to go to decay for want of proper attention. Why should this be? We are acquainted with some of Gibbons’ carvings, particularly those in St. James’s Church, Piccadilly, London; but whether they are in a state of decay unknown to any one, whether any one looks after them, or whether it is “nobody’s business” to do so, we cannot say. Every now and then the owner of some beautiful wooden carvings suddenly becomes acquainted with the fact that they are thoroughly riddled through by worms, and instead of having them looked after, they are pointed at as curiosities. Even the makers of “old furniture” take care that it shall be bored all over, to imitate the borings of worms.

But what can be the cause of this decay? It must arise from one of two causes; or, it may arise from both, viz. either the wood was not seasoned when fixed; or else the quality and description of the wood for carving purposes was not attended to. There cannot be smoke without cause, and worms cannot exist unless a suitable habitation is first provided for them. Hard white oak is close grained, and will scarcely admit moisture; whilst on the other hand the soft foxy-coloured oak from some parts of Lincolnshire, and other places, is so porous as to imbibe it easily and retain it; and consequently is liable to early decay: in fine, the heart of this is scarcely equal to the sap of hard white oak.

The English woods least liable to the worm for carvings are cedar, walnut, plane, and cypress; those most liable are beech, pear, alder, ash, birch, sycamore, and lime. All the fine carvings at Blenheim, Kidlington, and Wimpole are in _yellow deal_, while in the age just before nothing but lime-tree and soft wainscot were used. The beautiful carvings of Gibbons, in the chapel of Trinity College, Oxford, are wrought in costly scented cedar and rich dark oak; those in Trinity College, Cambridge, in white lime-tree wood.

There is no doubt that wood to be used for carving should be hot, pungent, and bitter: thoroughly obnoxious to wood-destroying insects. If we cannot obtain this wood in England, we certainly can abroad, and one shipload would last a long time for such purposes. Take, for instance, the _Jarrah_ of Western Australia; the _Determa_, the _Cabacalli_, and _Kakatilly_, of British Guiana; and the _Sepe_, of Trinidad: these woods are much valued where they grow, and no insects ever attack them. We do not say that they are suitable for wood carvings, but they might be tried, and we certainly know they are not likely to be worm-eaten at the end of a few years. They need not be discarded on account of their hardness; boxwood is hard, but some good carvings have been executed with boxwood. We can relate an anecdote about this wood. On 3rd June, 1867, Mr. W. G. Rogers, the celebrated wood-carver (would that he were alive now to read these words), was asked, at the Royal Institute of British Architects, if boxwood is objectionable for wood carvings,[38] and he did not reply to the question; if he had given his opinion it would have been a valuable one, coming from such an authority. We must therefore get Mr. Rogers’ opinion of this wood in another way. If the reader will refer to the “Reports by the Juries,” English Exhibition, 1851, vol. ii., page 1555, he will find the following words:

“W. G. ROGERS, of London.--A cradle executed in boxwood for Her Majesty Queen Victoria, and richly ornamented with carved reliefs; also, a group of musical instruments, among which may be especially noticed a violin. These works show an extraordinary dexterity in the treatment of the material, and the ornaments of the cradle are in excellent taste. Prize medal.”

We have already referred to the Report of the Commission on the Decay of Wood Carvings, and as this report is now rather difficult to be obtained, we propose condensing some extracts from it, which may prove of value to the reader.

Of the three species of beetles injurious to furniture and carved work, the first, _Ptilinus pectinicorius_ is about one-fourth of an inch in length, and the male is distinguished by its beautiful branched antennae; the second, _Anobium striatum_, which is by far the commonest and most destructive, is about one-eighth of an inch long and of a brown colour, with rows of small dots down the back; and the third, _Anobium tessellatum_, is about one-third to one-fourth of an inch long, the back varied with lighter and darker shades of brown scales.

These insects are produced from eggs deposited by the females in crevices of the woodwork, from which are hatched small white fleshy grubs resembling the grubs of the cockchafer in miniature, which generally lie curled upon their sides,’ making very little use of their six small feet fixed near the head; it is in this state that the insect is chiefly injurious, although the perfect insect itself also feeds on the wood. These grubs make their burrows generally in the direction of the fibre of the wood; but when it becomes thoroughly dry and old, they burrow in all directions.

When full grown they cease eating, cast off their larva skins, and appear as inactive chrysalids with all the limbs lying upon the breast inclosed in little sheaths: after a short time the perfect insect bursts forth.

The appearance of the insects in the perfect state takes place uniformly during the first hot days at the beginning of summer. Where they take a liking to a piece of woodwork, they seem to devour every particle of it, and as the perfect insects possess large wings beneath their hard wing sheaths, they are often seen flying in the hot sunshine out of doors, evidently in search of suitable woodwork for themselves and their progeny.

Experiments were made by Mr. G. Wallis, Secretary to the Commission, with a view of ascertaining the best means of stopping the decay when commenced. The course pursued, as well as the results arrived at, will be best illustrated by a summary of Mr. Wallis’s report on the subject.

The experiments may be placed under two heads, viz. Vaporization and Saturation.

I. VAPORIZATION.

At the end of April, 1863, when, from the appearance of certain specimens of carved work, the worm appeared to be developed and active, a large glass case, made as air-tight as circumstances would permit, was filled with examples of furniture, &c.

The bottom of this case was covered with white paper, and the specimens of woodwork were raised above the surface by placing blocks of wood at convenient points. This insured the free circulation of the vapour over the whole surface of the objects. A dozen small saucers, with pieces of sponge saturated with carbolic acid, were distributed about the bottom of the case.

The raising of the objects on blocks of wood facilitated the placing of these saucers at any desirable point.

The carbolic acid was, in this experiment, renewed every three or four days for a month, and a strong vapour pervaded the case for that period, daring which there was no appearance of worms, dead or alive. At the end of May the saucers were removed, and the doors of the case thrown open, so that it might be well ventilated and cleared of vapour, after which it was closed again; but the saucers were not replaced. This closing of the case without using the vapour was to prevent the escape of any beetles which might make their appearance, in the event of the vapour of the creosote not having destroyed the worms. About the middle of June, a fortnight after the case was closed again, beetles were seen crawling upon the white paper with which the bottom was covered. These beetles would, no doubt, deposit their ova in the usual course, as they could not escape, and a considerable number of them were found dead upon the white paper with which the surface underneath the carved work was covered.

In order to test the efficacy of chloroform and benzine, two small glass cases, as nearly air-tight as possible, were selected, in which were arranged early in May specimens of ornamental woodwork, all more or less in bad condition from the worm. The bottom of each, as in the previous experiments, was covered with white paper; and the objects to be acted upon raised upon small blocks of wood. In one case chloroform was used, and in the other benzine in a similar manner to the carbolic acid, i. e. by placing small pieces of sponge in saucers and saturating them with the liquid, using five saucers in each case. Both the chloroform and the benzine had to be renewed much oftener than the carbolic acid, as the liquid evaporated much quicker.

Within a week after the experiment commenced it was evident that the action of the chloroform had destroyed the worms as they came to maturity, and in a fortnight all the specimens of carved work having been taken from the case, and the dust produced by the action of the worms shaken out, a number of dead ones were found, as also some dead beetles; but these were evidently those of past seasons remaining in the crevices of the woodwork.

On examining the specimens of carved work placed in the case treated with benzine, there was no appearance of worms or beetles dead or alive.

The two cases, with their contents, were then kept open for a week, and thoroughly ventilated to clear them as far as possible of all fumes of either chloroform or benzine.

After this they were closed again, being then free from all traces of vapour, and were not opened for some months. Throughout the summer, the temperature being the same as that under which beetles appeared in the case treated with carbolic acid, no traces of worms or insects were visible, nor could the remains of any be discovered on the white paper, with which the lower surface of each case was covered.

It would appear then, as far as vaporization is concerned, that the action of the vapour of carbolic acid is not sufficient; in fact, it is sluggish and heavy, whilst chloroform and benzine are volatile and penetrating. The experiment with chloroform appears to prove that the vapour kills the worm, and, as no beetles appeared in the case during the summer, it may be inferred that it _killed all_ the worms within its influence.

From the pungency and penetrative action of the benzine, as also its volatile character and the fact that no life in the form of either worm or beetle was manifested in the case in which it was used, it seems fair to infer that it is more effective than even the chloroform.

Vaporization on a large scale might be adopted by having a room made as air-tight as possible, stopping up the chimney, pasting the window frames, &c., and placing infected furniture in the room, burning brimstone, or filling the room with fumes of prussic acid, chloroform, or benzine. It would have to be practised at the time when the perfect beetles made their appearance; their destruction at that time involving, of course, the prevention of further injury by their progeny.

II. SATURATION.

The experiments made with bi-chloride of mercury (corrosive sublimate) and methylated spirits of wine were not so successful as by vaporization, on account of the woodwork when dry (after having been saturated with the solution) having a varnished appearance.

No experiment as to the effect of saturation in a solution of corrosive sublimate in water was made: 1st, because of the great risk to delicate carvings or pieces of furniture by their immersion in water, or the bringing up of the grain of the wood by treatment with a brush; and 2nd, because the vaporization by benzine appeared to be quite sufficient to destroy the larvæ.

* * * * *

Before terminating this chapter, we trust a few words about carvers and carvings will not be out of place.

There are two kinds of carvers, the _house carvers_ and the _ship carvers_; the former are used to flat and square surfaces, the latter to the rake or fay, as was the old term.

About the period of Louis XIV. Malines was remarkable for its wood carvers, and the inhabitants might be seen sitting at their doors in the streets, plying their art in the same manner as now in many of the German and Swiss towns. Many works of art and decoration of Flemish origin are still preserved in England;[39] the works of Flemish carvers in wood were in great esteem, and there are numerous fine examples in the churches of Norfolk, and other parts of England which may be regarded as their productions. Evelyn remarked that Gibbons came from the Low Countries.

Grinling Gibbons created a school of carvers in England, and adopted a style and manner in building up his fruit and flowers to produce a grand effect. He chose but very few varieties of these out of his own garden, and it is wonderful how he varied and played with those few. He originated a peculiar description of light interlacing scroll-work, which is to be met with in his best works; no one has successfully attempted to carry it on since his time. There are several examples at Belton, and in the chapel and state rooms at Chatsworth, in the fine trophies at Kirthington Park; but the upper part of the reredos of St. James’s, Piccadilly, is a marvellous specimen.[40] The horizontal bands on the great organ in St. Paul’s Cathedral are the perfection of this character of foliated scroll-work.[41]

Gibbons’ carvings have a loose freedom about them. At Chatsworth he educated his workmen, who partook of his inspiration. There is a great deal of his work scattered over the rooms, great hall, and staircase of Lyme Hall, near Disley, which was erected under the direction of Sir C. Wren. It was executed by the persons who were employed at Chatsworth, and took nine years to complete.

At Blenheim there are some fine specimens of Chippendale’s work, but what it all means is a mystery. Such a mixture of scraggy birds, and flowers cut into shreds, pagodas, and rustic waterfalls--all this fine workmanship employed to produce nothing but an incongruous whole of absurd objects. There is a leading line in all these works, indicating what the old carvers used to call the C and G style; because if you attempt to draw it, it will resolve itself into these two letters. There is also the S and G style.

Abolish painting and we shall again have some fine house carvers.

We have already given the conclusions at which the Commission appointed by the Department of Science and Art arrived, as to the prevention of decay or attack by these insects, and will now conclude this chapter by quoting Dean Swift’s recipe for getting rid of the Anobium or Death watch:--

“But a kettle of scalding hot water injected, Infallibly cures the timber affected; The omen is broken, the danger is over, The maggot will die, the sick will recover.”