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their eyes to the emporium of magnificent buildings in foreign parts, will they not be convinced, that the long duration of timber was the grand cause for such magnificent erections ? Seldom or ever wanting repair, consequently one stupendous pile was erected after the other. If, with a little expense, the timber of this country, as well as that brought from foreign parts, can be made as durable now as in those times, may not the same spirit for magnificence arise in this country? There is no article of more interest and consequence to Great Britain, than timber, both for ship and other building; yet there is no article so neglected in study or practice to improve its durability; and it is often half decayed before brought into use.

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ON THE EXISTENCE AND PREVALENCE OF DECAY IN TIMBER.

No person, it is supposed, can be so little acquainted with Natural History, as to be ignorant that, although the progress of growth in timber trees is slow and gradual, yet, when once arrived at maturity, its advances to decay are abundantly rapid. Nor is it imagined necessary to inform any one of the fact of the actual existence of the disease in timber, denominated the Dry Rot; or to remind him, how often it has occasioned expensive litigations between builders and their employers, in order, when it has occurred, to ascertain and determine on whom the loss and expense, which it has produced, ought, in justice and reason, to fall : but it may be, perhaps, matter of new and original intelligence to many persons, to be told, that this evil exists, to an astonishing extent, among the shipping in this and all other countries in Europe, whether employed in the Navy, or for commercial purposes ; that no building, in which timber is used, is secure from it, even though the timber has previously undergone the usual process of seasoning ; and that a remedy for it, in the case of the Navy of this country alone, would prove, as has been ascertained on an accurate computation, a saving, in the short period of every fourteen years, of not less than twenty millions, at a time when this country is at war.

By persons best acquainted with the subject, it has been ascertained that, on an average, every ship in the Navy, and in the Mer

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chant service of this country, trading to the East or West, or any hot climate, is, in consequence of repairs from time to time made, for the purpose of taking out decayed planks and replacing them with new and sound, very nearly wholly rebuilt in the course of fourteen years. Besides this, it is not uncommon to see a stupendous ship, which has cost the owners fifty thousand pounds in building, condemned to be broken up in a few years ;-comparatively few, when we consider that timber is of nearly 200 years' growth before it is fit for large ships.

Even in private life, it is no less frequent to find, that whenever a nobleman or gentleman has been at the expense of building or purchasing a noble mansion for his residence, the purchase money has been only a part of what he has had to pay; for the building has been subject to the dry rot, and, in a very short space of time he has had to expend as much more in repairs, in order to remove decayed timbers, and supply their places with sound.

Any discovery or invention, which would in any considerable degree lessen these evils, by retarding, even for a few years, the decay of timber, would so far be entitled to encouragement; but one, if it could be found, which should effectually stop it, by disuniting the principles from which the decay of timber must arise, cannot be too highly praised, or too strongly recommended. That such a discovery is still within the reach of possibility, and even of probability, notwithstanding the failures of those who have hitherto professed to suggest a remedy, it is reasonably presumed will be fully demonstrated in the course of the ensuing pages ; and that such an one has been actually found, will, it is imagined, be no less evident, from consulting and weighing the experiments hereafter stated :-it is not the mere hasty suggestion of the moment, but the result of deliberate investigation. Every experiment, that could be suggested, has been tried ; and although those stated are only a small part of what have been made, because it would have been too tedious to have inserted the whole, yet it may with truth be asserted, that in no one instance has any failure occurred. And to such an extent has the desire for ascertaining the facts been carried, that gentlemen of the best abilities and information, chemists of the first celebrity and talents, and others in various departments, have been, at different times, consulted on the surest methods of evidencing the positions on which it rests. It has stood them all ; and it is conceived that these tests are decisive, and justify its author in asserting, that the desideratum is at length obtained, and that the advantages arising from it will be of the first and highest importance. Some of these will be found hereafter pointed out ; but to anticipate all the modes in which timber or wood may be

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applied, and consequently to state the whole extent of the benefit, is not, perhaps, within the compass of possibility.

SECTION II.

ON. THE CAUSES OF THE INTERNAL DECAY OF TIMBER.

The principal reason why former attempts have not generally súcceeded has been, that their authors have not considered the primitive question in its full extent, but have taken it up only just at that part when decay appears, in which it was evident that the application of some remedy was necessary ; though, it is plain from their failure, that they had no idea of what kind the relief ought to have been. They have not endeavoured to trace the cause and source of the evil, by an investigation of the circumstances attende ing the growth of the tree, from the time when it first begins to shoot up from the earth, or the decay of it, since it arrived to maturity ; but have confined themselves solely to the object of stopping its progress, by the application of some palliative, which might, for a time, counteract or retard putridity. They were not aware, that the natural constitution of the tree might, perhaps, produce some principle hostile to that on which their system was founded: nor have they been sensible, that the union of two principles, innoxious in themselves, might produce a third by no means of the same nature; and that, although their proposed remedy might not be calculated to increase either of the two first, it might yet prove ineffectual to prevent the production of the last, and so be defeated in its intention.

To avoid a similar inconvenience in the present case, the nature, constitution, and growth of timber and other trees, in all their various stages of progress, either to maturity or subsequent decay, have been most assiduously studied and examined; and the inquiry has produced the following observations as its result, which, as being the only solid foundation on which a remedy can be applied with any hopes of success, are here communicated.

The laws of matter and motion, of gravity and attraction, are by no means peculiar to the solar system, but equally prevail in the animal, vegetable, and mineral kingdoms also ; and without the assistance of the laws of motion, no phænomenon in nature can be successfully investigated or explained.

Now, the first law of motion is, that all bodies have an equal indifference to motion or rest, and therefore require some other power to put them into either of those situations. If once at rest they continue so till some power, acting upon them, sets them in motion ; and when once put in motion, they persist in it, moving in the direction of a straight line, unless some other power interposes to check their motion, and set them at rest. Till this power occurs, their motion will still continue the same as at first, even after the power, which set them in motion, is removed; for the power of motion, having been once communicated, does not require constant application or continuance, unless some impediment, such as the air, &c. be encountered.

The second law of motion is, that the degree of motion is always commensurate to the force applied ; and that the change, from rest to motion, or from motion to rest, is never sudden, but gradual, from one degree to a less, and so ultimately to the contrary of its original situation ; and that the proportion of these minor degrees is always adequate to the power opposed. A body at rest, when acted upon by any power, yields to that power, because it has not the contrary faculty or quality of resistance : it moves in the same straight line in which the force applied is directed, and acquires a greater degree of velocity in proportion to the greater degree of the force of the power applied; so that, if the power be increased to twice its original force, it will communicate a double degree of velocity to the object on which it acts. If its power be advanced to three times, the velocity will be increased to three times also.

To apply these principles to the present purpose, it is only necessary to observe, that, by the action and power of fermentation, the effect of heat and moisture united, the vegetation of a tree is set in motion, and that heat and moisture are the vital principles for the growth and nourishment of the tree : by a chemical union they produce fermentation, which creates motion, and would, in itself, destroy the tree, if it were not for a continual supply of cool matter from the roots, and the faculty of discharging, by evaporation, all the superfluities of heat and moisture in perspiration, thus preventing putridity.

But when the tree is cut down, although it contains the quality of being acted upon by heat and moisture, it loses those powers, from the want of a supply of the juices from the roots, and the faculty of discharging, by evaporation, the superfluities of heat and moisture, from which putridity proceeds; the consequence is decay.

The motion of the juices is as necessary for the preservation of the growth of the trec, as rest, in the same matter, is necessary

for preservation of the timber, when cut down. If the former is

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