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en there is not time for actual drying, the best method8tt en ® an .l> e adopted, especially for sappy timber, and, if1 10 ia| 18 not P rinci P al, y required, is immediately, on felling,tnei 'se it in running water, and, after allowing it to1\i a n "‘ere about a fortnight, to set it in the wind to dry.less r ^*. der s timber less apt to crack and warp in drying, andeCt to " e worm ' eaten > especially the more tender< *>t it must be altogether under water, as partial"‘Of' 011 ' S vel y destructive.

■t Uj ste eping generally, whether in cold or warm weather,St " e observed, that it dissolves the substance of thedint - 3 and necessarily renders it lighter; therefore the lessr, °t'vit| neCessar y the better ; indeed, it is known, that,? 0 r l( j ..landing wood that is completely submersed remainstetf a i ° r a ver y great period after the water has dissolved a“til j s °luble part, it is, when taken out and dried, brittle,“P ever y respect unfit for use.

tbe P ur P oses of j oinery, steaming and boiling are verydiey^ ®tnods, as the loss of elasticity and strength whicht'liijjJ. °'mce, and which are so essential in carpentry, is com-'hir a i... by the tendency to shrinkage being reduced ; thehorn lf y also is rather improved than otherwise, at leastea ming. It has been ascertained, that of woods sea-t ' lese methods, those dry soonest which have been^ a 'il ’ but *" e dl 7 in S e 'ther case should be somewhatl, ig . ‘ ’ a ad four hours are sufficient for the boiling or steam-I^°cess.”

Sth e f 0t1 ’ 8 m ethod of seasoning by extraction of the sap, is1,1 ’ s cons ' dered well worthy of notice ; it consists

" le timber into vertical iron cylinders at top ; andV % m ei '. bein S heated, and steam used to produce a partial

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f r * 1116 sap relieved from the atmospherical pressure

'‘tf tl ir °»» the wood, and, being converted into vapour, passesdf]nj r( , u 8h a pjpg provided for the purpose. The time'tgs. _ 18 about ten weeks, and the cost is about ten sliil-1 'cad ; but the sap is wholly extracted, and the tim-!’> \vj t | Und read y f° r any purpose ; the diminution of weightb ytl le „ a Httle more shrinking, similar to that in seasoningSaer ti.

f ° ttl oke I ^ rnon natul ' a ' process.

6li dr y> n g in an open chimney, or the burning of furze,^<1 (Ju^’nigs, or straw under the wood, gives it hardness

’ '•''em ,Ult y i and by rendering it better, destroys and8 Worms; it also destrfor 0a y have commenced.

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bidj 18 Worms; it also destroys the germ of any fungus; have commenced. Scorching and charring areJ dof le Preventing and destroying infection, but have to°'vly, and only to timber that is already thoroughly| 0,1 of a ’ °. t ' 1 erwise, by encrusting the surface, the evapora-j'pO't R0( a y internal moisture is intercepted, and decay in thef l(! 8 Urf. n ensue s ; if done hastily, cracks are also caused on' Jf Mli ^, and which receiving from the wood a moistureler s j, 1 t ' 1 ere is not a sufficient means of evaporation,fa ar iou S °° n "able to decay.

C Sfe Ts 0 S - Itlet bods have been from time to time proposed' v hi .‘," g "mber, and preventing its rapid decay ; buth ars > " ave most engrossed the public attention of latejt^ott’s '° se respectively distinguished asKyan’s, Payne’s,t^Oal, -yX >atents , &c. In the year 1833 to 1836, at thefjj, 611- obj e . t 0o l w ich, experiments were instituted, having fortbe establishing or otherwise the claims of thatand the results of which were of a very satis-S uhn,- Ure ’ the Kyanised specimens generally, whichivjbfee ted to the fungus-pit when taken out at the end!>iiv bel'tg sound, while duplicate pieces unprepared

tij ev er, v, ln v arious stages of decay. Certain questions,' 0r > to Resented themselves :—1st. Whether the impreg-nable u' Ch t *‘ e timber had been subjected, might not be°y some cause, and perhaps generate an atmo-

sphere noxious and injurious to health. 2nd. Whether thestrength of the timber were impaired or otherwise. Thefirst was satisfactorily determined by Dr. Faraday, whoproved by experiment, that the combination was not simplymechanical, but chemical; and that a permanently compoundmaterial was formed ; the second was formed by experimentsmade by Captain Alderson, C.E., upon ash and Christianadeal, and which showed that the rigidity of the timber wasenhanced, but its strength in some measure impaired, itsspecific gravity also being somewhat diminished. Anotherquestion yet remains open—how far, since the impregnationhas not been traced to a depth greater than half an inch,does this process meet our requirements, and after the satis-factory conclusion arrived at as above related, and the evi-dence of the facts upon which it was so reasonably founded,how are we to meet the assertion of Mr. Pritchard, C.E. ofShoreham, made in 1812? The sleepers Kyanised five yearsago, and in use at the W. I. Dock warehouses, have beendiscovered to decay rapidly, and the wooden tanks at theAnti-Dry-Rot Company’s principal yard are decayed.

Mr. Kyan’s infusion is corrosive sublimate, and the processconsists in submersing the timber in tanks for about a week,then taking it out and drying. Sir Humphrey Davy hadpreviously recommended a weak solution of the same thing,to be used as a wash where rot had made its appearance.Dr. Birkbeck made a favourable exposition of the process aspursued by Mr. Kyan. Sir John Barrow and the Duke ofPortland impugn it, and Lord Manners and Dr. Moore followon the same side. The Payanising process, besides profess-ing to preserve timber from dry-rot and the ravages of insects,is said to render it uninflammable, or at least to deprive itin a great measure of combustibility.

Sir William Burnett’s patent process seems to have metwith great, and, as we think, deserved success. The varioustestimonials that we have seen in favour of it, and the timethat it has maintained itself in the opinion of the public,induce us to think well of its efficacy in performing what itprofesses to do. Even if not quite realizing all its inventorsclaim for it, it certainly will effectually preserve timber fora great number of years. The effects ascribed to it are, thatit hardens and improves its texture. It enters into perma-nent chemical combination with the ligneous fibre, and doesnot come to the surface of the wood by efflorescence, likeother crystallizable salts, and no amount of washing or boilingin water, will remove the chemical compound so formed.

It preserves wood and other articles from the adherence ofanimal and vegetable parasites, and also from the attacksof insects, and from ivet and dry rot. Further, it renderswood uninflammable, when used of a certain strength.The basis of his process is chloride of zinc, or, as it is morecommonly called, the muriate of zinc, which seems to havea peculiar affinity to woody fibre, entering into intimateunion with its component particles, and forming as it werea new mineralized substance. There is a chemical combina-tion of the metallic base ; not merely by a mechanical altera-tion of the position of matter, which might again be disunited, jThere is no decomposition produced, but the fibre of the jwood appears to be permanently pervaded by the zinc, and jthe atoms of which they are formed enter into a new |and fixed arrangement. !

SECANT, (from the Latin seco, to cut,) a line that cuts janother, or divides it into two parts. '

In trigonometry, the secant is a line drawn to the centrefrom some point in the tangent, which consequently cuts thecircle.

SECRETARIUM, the vestry of a church, the same asSacristy.