interior layers of the wood are annually acquiring more and more solidity, by assimilating to themselves the sap in its ascent, and a portion of which is indurated. Thus the sap, which by the ordinary method of seasoning timber it is intended to expel, is in this manner, for a certain period, filling up the pores of the wood, until its functions completely cease.

There is an evil, to which timber is much exposed in the progress of seasoning, to wit, that of rifting or cracking, caused by the sudden contraction of the exterior surfaces of the wood which have first parted with their moisture. It will readily be perceived that, as the timber when used is placed upright, each of these cracks or rifts becomes a channel to convey water into the very body of the wood. This very serious inconvenience is only to be obviated, if at all, by a gradual and uniformly accelerated desiccation, which we think is in a great degree effected by this mode of drying timber; for as the functions continue gradually to diminish until the tree expires, the sap juices are withdrawn from the interior to the exterior of the tree, and either evaporated, or exhausted in the formation of buds.

The usual mode of treating timber appears to us to be very imperfect. The tree is cut down in the autumn, or beginning of winter, under the idea of its containing at that time less sap than at any other season of the year; it is then hewn and housed under sheds open all round to admit a free passage of the air: both of these procedings are founded in error. The pores of the wood contain nearly as much sap in the early part of winter, as at any other season of the year. For as the sap which produces the leaves and buds in the spring cannot have been transmitted from the roots that season; the supply must be derived from the cells of the wood, which are a kind of storehouse of sap to furnish a stimulus for the latent energies of the spring shoots, and which, from the physiology of vegetables, as well as the ordinary operations of nature, are first brought into action by the returning heat of summer. The roots are much later in being acted upon by this heat, and therefore do not acquire sap until some time after the buds of spring have put forth. It is reasonable therefore to infer, that the pores of the wood are most clear of moisture at some moment after the first budding and before the full development of the leaves, and that the tree should then be cut down. The cold, or frost of winter, is also an important agent in hardening the soft portion of wood formed in the previous summer; a circumstance which is not sufficiently estimated in the preparation of timber. We think, therefore, that the tree should be felled in

the spring, and left, with its leaves and branches undisturbed, until the spring following, before it is trimmed for use. In order to avoid as much as possible rifts or cracks in timber, it is necessary that it should be seasoned gradually, and that the process of drying should, as far as it may, not be interrupted or too rapidly accelerated by the alternations of heat and cold, dry and wet this can alone be accomplished by placing the timber in close buildings, into which air may be admitted or excluded at pleasure. Still experience has shown us, that this treatment is not sufficient to prevent those openings in the wood which admit water.

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The subject of seasoning timber, or expelling the internal causes of decay, which generally produce what is called dry-rot, was first treated of by Vitruvius, who wrote in the reign of Augustus Cæsar: and it is truly remarkable, that the learning and experience of eighteen centuries should have added so little to the stock of information which the world then possessed upon this important subject. Ware, who wrote about the year 1767, remarks, that There are many rules laid down respecting the felling, management, and seasoning of timber; and they are re'peated through all the works of those who have written upon the subject. The English reader will smile to hear that they ' are all extracted from the Roman oracle, Vitruvius; but when 'he sees how little the moderns have been able to add, he will 'be pleased to find those rules are confirmed by the experience of 'so many centuries.' Vitruvius' method is then stated to be the felling the tree in winter, and on the decrease of the moonthe timber to be laid up in a dry airy place, where the rain and sun do not come. Evelyn, who wrote in 1662, says, 'Lay up 'your timber very dry in an airy place, yet out of the wind or 'sun, and not standing upright, but lying along, one piece upon ' another, interposing some short blocks between them, to pre'serve them from a certain mouldiness which they usually con'tract while they sweat, and which frequently produces a kind ' of fungus, especially if there be any sappy parts remaining.' The injury arising to timber from splitting, which is almost always produced by this mode of seasoning timber, was early noticed: hence Evelyn observes: 'Some there are yet who keep their timber as moist as they can, by submerging it in water, which 'they let it imbibe to hinder the cleaving; and this is good in fir, 'both for the better stripping and seasoning; yea, and not only ' in fir but in other timber. And again, Elm, felled ever so green for sudden use, if plunged four or five days in water, (especially salt water,) obtains an admirable seasoning, and may 'immediately be used. I the oftener insist on this water season'ing, not only as a remedy against the worm, but for its efficacy ' against warping and distortions of timber, whether used within VOL. III.

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or exposed to the air." Pursuing the same subject, he remarks again, Timber which is cleft is nothing so obnoxious to rift and cleave as what is hewn; nor what is squared as what is 'round and, therefore, where use is to be made of huge and massy columns, let them be bored through from end to end; it is an excellent preservative against splitting, and not unphilosophi'cal.' The Venetians (says Ware) sink their oak two or three years under water before they use it, and no method better prevents its splitting.' And again, It is found that split pieces are not 'so apt to crack as the entire ones; and even that which is only squared escapes better than such as are left round.'

We have been thus full in our extracts from these authors, in order to show the coincidence of opinion and of practice, in seasoning timber, from the earliest periods to this time. Notwithstanding the increased interest of the subject, produced by the wonderful extension of ship building both for merchants' and government's service, our knowledge of this matter remains pretty much the same as it did eighteen hundred years ago :— For if the report of our Commissioners be properly considered, it recommends nothing more than was then taught, and what seems never to have been doubted-that is, to protect the timber while seasoning from the weather, or, in other words, to frame the ship under cover, and let it so remain until wanted for use.

The English nation, from whom we inherit so many valuable institutions, and from whom, above all others, we should have expected something progressive and satisfactory upon a subject in which both their pride and their safety are so intimately concerned, have made no improvements in the art of preserving timber from decay and, indeed, it would seem from the following observations in one of their periodical journals, (the retail stores of their greatest learning,) that they had lost, or at least neglected to make use of, the little valuable information upon this subject, which their ancestors had bequeathed to them. The writer, in commenting upon the observation of Mr. Pering that the duration of a modern built fleet of government ships may be limitted to eight years, remarks :—

This is indeed a gloomy prospect, but is it a faithful representation of the fact? We are inclined to think it is not, and we shall come nearer the truth in stating, that except in some particular cases, the period of ten years may be assigned to ships of war, built in merchants' yards, and fifteen to those built in the king's yards, and that twelve and a half may safely be taken as the average duration of a fleet of modern built ships Even this is sufficiently discouraging, when compared with the duration of ships in earlier periods of our naval history. The Royal William, for instance, a first rate, was built at Portsmouth, in 1719, was among the first ships sent to the re

lief of Gibraltar, in 1782, and at the age of near a century bears the flag of the port admiral at Spithead. The Queen Charlotte, a first rate, was launched at Deptford in 1810, sent round to Plymouth under jury-masts in 1811, found too rotten to be sea-worthy, and is now undergoing repairs which we imagine will cost at least £20,000. These, we admit, are extreme cases of durability and decay: but we could easily furnish a hundred instances of the superior quality of ships built in former days to those built in our own time. The Sovereign of the Seas,' afterwards named the Royal Sovereign, was built at Woolwich, in 1637, and stood forty-seven years' service. The Barfleur, built at Chatham, in 1768, is still a good ship, and now under repair for further service. The Montague was launched at Chatham, in 1779; after undergoing several repairs, she now carries the flag of Admiral Dixon, at Rio de Janeiro; whilst the Ocean, the Foudroyant, the St. Domingo, the Rodney, the Ajax, the Albion, and many others, were falling to pieces within five years after launching, and some of them in less than three.'

If this be a true picture of the state of the navy of England, we think her considerably behind the other nations of the world in one of the most important branches of ship building, to wit, the durability of the materials: for we feel confident that there is no nation, the Turks probably excepted, who can exhibit a parallel case to this. We are not as yet old enough, as a naval nation, to enable us to estimate with precision what term of duration belongs to our ships of war; but we have sufficient information upon the subject to justify us in stating that their term of duration will equal, if not exceed, twenty years. It would have been not a little satisfactory to learn, what were the peculiar circumstances under which those vessels were built, that have proved so creditable to the former, and so discreditable to the present race of Britons: but, in truth, England, strange as it may appear, has systematized no plan by which experience can furnish any lessons of wisdom upon this subject; and the whole amount of their intelligence seems to be derived from tradition, or general report and opinion, rather than from any connected series of records and ob servations. Hence the relation between cause and effect, which can only be made manifest by observing, link by link, the chain of connection, rests entirely upon conjecture.

Some attempts have been made, however, to arrive at a better state of things; which, feeble as they are, deserve our notice. In the year 1691, Dr. Plott read before the Philosophical Society of London, a paper, in which he recommends the practice of barking the tree intended for ship timber, in the spring, and suffering it to remain standing for two or three years; observing, that if thus treated, the sappy parts become as firm and durable as the heart: and as an evidence of the efficacy of this mode of managing timber, he states, that the "Sovereign of the

Seas," after 47 years' service, was then a sound ship, and that the antient timber remaining in her was so hard that it was no easy matter to drive a nail into it. In the year 1738, Buffon read before the Royal Academy of Sciences at Paris, a paper containing the results of many years' experiments, which fully confirmed the hypothesis of Dr. Plott. In 1787, the Navy Board of England caused some trees to be stripped of their bark, after the manner before recommended; and directed the Hawke sloop of war to be built in 1793, one half with this timber, and the other with timber obtained in the usual way. It is said that the experiment did not result favourably to the timber which was barked; for, this vessel having been broken up ten years after she was built, no visible difference could be observed in the timber, all of which, it is stated, was found to be equally decayed. No experiment seems afterwards to have been tried, at least as far as we are informed; and indeed such has been the peculiar situation of England, since that period, that her necessities did not allow, it would seem, either time, opportunity, or materials for experiment-her immediate safety, until recently, having been the chief object of her concern. Admitting that the instance of the Hawke sloop of war is against our hypothesis, yet we should have been much better satisfied to be made acquainted with all the circumstances having a bearing upon the question; such as whether she was faithfully and carefully built; upon what service she was occupied; whether employed in a hot or cold climate; and whether her commander was a neat, or a slovenly and careless man. We should have been glad to know, how many, and what timbers of each kind were destroyed, and to what extent. Each of these considerations enters materially into the subject; and without them we cannot form a proper conception of its true state. Meagre as the information is, however, we think it makes against us—and must, for want of more light upon the subject, oppose to it the opinion of enlightened men. Dr. Plott is very positive in his assertion of the efficacy of this mode of preparing timber, mentioning, as an instance, the "Sovereign of the Seas;" and Buffon, in a series of experiments, has fully proved that timber thus treated acquires additional solidity, firmness, and strength. The French nation have, for a long time past, entertained the opinion that stripping the bark from the tree, while standing, contributed to its durability; and we are not aware of their having, in practice, been disappointed in the expectations they had formed of its efficacy. Upon every principle, therefore, of estimating testimony, we must consider our case fully made out; and until farther experiment, judiciously conducted, shall disprove our positions, we shall hold the plan proposed by us, as highly conducive to the durability of ship timber.