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is on the present occasion produced by the mere use and application of the composition.

The next succession of experiments was intended for the purpose of ascertaining, whether the composition could or not, in any way or to any extent, be extracted or expelled, or forced out by any high degree of temperature, or by the alternate variation from high to low, or from low to high.

12. To decide whether the composition could be disturbed or set free by heat, some pieces of all sorts of wood were desiccated, or well seasoned, and then saturated fully with the composition : after the composition became somewhat concrete, they were for three days placed in an oven, heated to not less than 80 degrees, but it had no effect; for no loss of weight was sustained, or next to none, that being fixed air, for it amounted to no more than a drachm in a pound, which does not exceed a one hundred and twenty-eighth part; nor was there any appearance of external motion, which proves the composition immoveable by confined heat.

13. They were then placed in water for several days, and again deposited wet in the oven, heated as before ; but still there was no effect to disturb the composition, although the pieces had sustained alternate heat and moisture, and afterwards been again subjected to heat.

14. A piece of larch, weighing six ounces, having three ounces of composition in it, which is a very great portion, and must have moved, if it were moveable, was boiled for two hours in water ; but still there was no effect, either to dissolve the composition, or admit

any

fresh quantity of water; if it had been possible to dislodge or extract any of this composition, surely this experiment would have done it.

15. A piece of oak, of about two inches square, having in it full half an ounce of composition, was also boiled in water for six hours; but there was still no effect towards disturbing or setting free the composition; and it was considered, on this occasion, that the smaller the cuttings or sections, the more severe the effect.

16. Sections of deal boards, prepared with the composition, and others not prepared, have been laid in the ground in a wet ditch for several weeks together : in this case, the sections prepared have become somewhat heavier, but when placed in the oven, they returned to their former weight as before put in the ditch, but not less. The increase in the weight would, however, never have occurred, had the wood been completely saturated, which it was

not.

The case was evidently different from that above described, with the sections not prepared with the composition, for those pieces were double their original weight when taken out of the

ditch, but much reduced in their original weight after desiccation in the oven : these circumstances evince, that there was in the latter case some degree of decomposition, but none in the sections which had been prepared, as they could not be reduced below their original weight when put in the ditch.

Though wood becomes, in consequence of being repeatedly wet and dry, liable to be sometimes heavier, and sometimes lighter, in proportion as heat or moisture most prevail at the time, yet the tendency of seasoning or desiccation of timber is at all times to render it lighter than before, and intended to give it the power of always afterwards continuing so, without experiencing any increase of weight in consequence of any moisture to which it might be afterwards exposed: but this can be only to a certain extent;, and after it is once thoroughly dry and seasoned, it will still always vary in weight when exposed afresh to wet and dry, unless it is prepared with this composition.

The foregoing experiments, though made at first only with a view to substantiate the facts which they are here adduced to prove, have also led to a very important discovery, by means of which timber, of any dimensions, may to a certainty be perfectly seasoned, without cracking, rending, or splitting at the ends, and this by a method completely practicable.

So important are the points decided by the foregoing experie ments, that it is imagined few other tests can be suggested ; and at present, indeed, only the following question has occurred to the mind of the author of this Treatise, as necessary to be solved, whether the composition has or not, the power and ability to prevent the formation of fungi in decomposed wood ?' For the ascertainment of this, several experiments were tried : no one failed; and the result of the whole resolves itself into the following conclusions, which, in order to render them more intelligible, it has been thought necessary only thus briefly to state.

17. A section of decomposed light elm slab, about twelve inches square, all sap, but apparently dry, unprepared with the composition, was placed in a cupboard, and produced, at the end of ten weeks, an appearance of fungus, covering about two inches in length and one in breadth.

18. Two similar sections from the same slab, prepared with the composition, but deposited in a damp vault, known to contain carbonic acid gas, at the end of the same period of ten weeks, produced none.

The unprepared section above-mentioned (17), which had lain for ten weeks in the cupboard, and on which a fungus had already appeared, was cut in half: one of these half sections was placed in the vault, and in four days the fungus had considerably increased.

At the end of ten days, the whole piece was completely covered with a milk-white Turk's cap and Jew's ear fungus. This section was several times disturbed for the purpose of exhibiting, which broke off the fungus ; but, upon being replaced in the vault, it always again recovered its growth : one of the sections (18) which had been prepared, and which had lain in the vault for ten weeks, without any appearance of fungus, was brought up and placed in the same cupboard for twenty weeks, with intention to ascertain whether the change might encourage the production of fungi; but at the end of that time it exhibited no appearance of fungus whatever.

The other section (18) of the prepared slab had now lain in the vault thirty weeks: at the end of that period no one symptom of fungus was produced ; a sufficient proof, as it is contended, of the impossibility that fungi should generate on wood so prepared, even although it should have been decomposed.

19. In order that no question might remain behind unsolved, it was, in consequence of the effect which the composition was found to have had on the porous or soft woods, determined to try also what would be its effect on the sap or alburnum of oak.' The composition was applied to some sappy loppings of oak, and it succeeded beyond the most sanguine expectations which could be formed. The specimen on which this experiment was made is to be seen, as well as all the others here mentioned, and without exaggeration, although no description can do justice to the effect; suffice it to say, that the sap or alburnum is harder and closer than the heart, and is equal to any purposes to which the heart can be applied.

20. and last experiment, was to prove, that oak or fir, that would not rend straight before prepared, is found to rend in great perfection after prepared, which is another proof of its compressive powers

Timbers of large dimensions (if 18 inches square, and 80 feet long) can be done with facility, and with greater effect, as to strength and durability, than the small sections here taken for experiments.

SECTION VI.

CONCLUSION.

TIMBER can never so alter in its constitution, as that what will affect a small piece, should not equally operate upon a larger. And such has been the success of the experiments, already stated, as to justify an assertion, that, if tried on a larger scale, their result would be the same. The only thing, therefore, which can now be wished for, would be a full and fair opportunity of trying, on an extended scale, the effect of the composition, by applying it, under the direction and inspection of its inventor, to some of the frigates or other ships now building or repairing in the several public and private dock-yards in this kingdom. To the granting such an indulgence, and the further additional means necessary for its success, by those persons, in whose power, from their situation, it is to grant the permission, and whose object it must unquestionably be to introduce into their several departments every really beneficial invention and improvement, very strong reasons may be adduced. For it is to be remarked, that every one of the above experiments is directed to, and tends to establish some very essential point ; that the process and result have been so clearly stated as plainly to show how, and why it has succeeded ; that

these means, the whole is rendered so extremely intelligible, that almost any one can judge of it; and that a failure in success is by no means probable, as it is manifest, from the evidence which he has produced in his pamphlet, that the author has a clear conception of the nature and extent of his subject; and has consequently expressed himself in terms, which cannot be mistaken or misunderstood, and it is the intention of the author to apply his remedy for the public good, if supported. This has not been the case with those, who have undertaken to suggest remedies : the whole of the pamphlets before written on the present subject, only recommend the public to try the remedies they propose, and publish their book for sale': the present treatise is not intended for sale, but may be had gratis. At some future period, a more elaborate treatise of the present matter, and all new matter that may arise, will be published in the usual way.

On the present occasion, it may fairly be asked, What more could have been done, than what was actually tried, to ascertain the real power of the remedy suggested? Can any one point out an error in the facts ? a failure in the conclusions or deductions ? or a fallacy in the arguments or reasons assigned ? or can any, impartial person, among all those best'acquainted with the principles of chemistry, and the rules of logic and reason, affirm, with any hope of establishing such an assertion, that the facts here adduced do not amount, not only to probability, but even to mathematical demonstration ? It cannot be denied, but that the object is one of the greatest importance to the nation at large, and to all individuals who have any concern with the use or employment of timber; and, under the above circumstances, it is hoped that those, in whose department it particularly lies, will in earnest exert themselves to enquire into the evidence of the facts here stated ; a degree of atten

for a

tion to which, from their importance, those facts seem justly entitled. Further hopes and expectations are also entertained, that the result of that inquiry will be an inclination or disposition to adopt, if it is properly substantiated, the remedy proposed; and a readiness to grant and furnish every necessary means in their power full and fair trial, on the largest and most extended possible scale. And lastly, the author trusts, in full confidence of establishing his assertions and conclusions, that neither prejudice in favor of former erroneous opinions, nor particular interest, should any such be exerted in opposition to sentiments better entitled to reception, shall be permitted to operate to the ultimate total exclusion, or as any impediment to the admission, of a project, which, if duly established, as it will be by experiment, may be justly considered as being, in its extent and utility to the public, perhaps one of the most valuable discoveries that has taken place, within the compass of the two last, or indeed of any preceding, centuries,

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