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CALL FOR MEETING.
BOSTON, Oct. 6, 1891.
DEAR SIR: The stated semi-annual meeting of the Association will be held at the Massachusetts Institute of Technology, Boylston Street, Boston, on Wednesday, Oct. 28, 1891, at 10 o'clock A.M.
Topics heretofore discussed will still be in order if called up by any member; and, in addition, the Board have the pleasure to announce the following: —
Col. JAMES FRANCIS of Lowell, Mass., will present a paper on METHODS OF PRESERVING TIMBER IN SITUATIONS WHICH EXPOSE IT TO DECAY.
Mr. SAMUEL D. CRAFTS of Boston, Mass., will read a paper on WOOD VULCANIZING.
Mr. FRANCIS P. SHELDON of Providence, R. I., will present a paper upon POWER AND SPEED IN COTTON MILLS.
Copies of these papers will be printed in advance of the meeting, and will be supplied to any member who shall apply for them to the secretary.
By order of the Board of Government,
Pursuant to the foregoing notice, the stated semi-annual meeting of the Association was held at the Massachusetts Institute of Technology, Boylston Street, Boston, on Wednesday, Oct. 28, 1891, at 10 o'clock a м.
The President, Mr. WALTER E. PARKER, Occupied the chair. The President submitted the following nominations of new members, recommended by the Board of Government, for election:
The foregoing names were then voted upon separately, and each nominee was duly elected to membership in the Association.
The President then introduced Col. James Francis of Lowell, Mass., who read the following paper:
METHODS OF PRESERVING TIMBER IN SITUATIONS
WHICH EXPOSE IT TO DECAY.
BY JAMES FRANCIS, LOWELL, MASS.
The perishable nature of wood, especially when placed in situations where there is an excess of moisture in the surroundings, has led to many experiments with a view to discover a process of treating timber with salts or oils, that would preserve it from decay.
Dry rot, sometimes called sap rot, the most formidable. disease to which timber is subject, is commonly attributed to a combination of the acids found in the sap with the oxygen of the air, which produces fermentation followed by decomposition. Unseasoned timber, placed in damp situations with but partial ventilation, will soon show signs of dry rot. Beams which presented the appearance of being sound on the outside have been found completely rotten inside. The shell remains sound because it becomes seasoned, and relieved from the sap.
Wet rot, as distinguished from dry rot, is considered to be occasioned by alternate exposure to moisture and dryness, beginning at the surface of the timber and working inwards. Piles and other timber placed in salt or fresh water will show signs of wet rot at the water line, before it attacks other parts. Posts, set in the ground, first begin to rot at the ground line.
Among the earlier investigators on the subject of preserving timber may be mentioned Johann Glauber, the famous chemist of Carlstadt, Germany, who in 1657 experimented with vegetable tar and pyroligneous acid; the wood having been first carbonized by the action of fire, then covered with a coating of
tar and immersed in pyroligneous acid.
Since then up to 1846 no less than forty-seven different processes, adapted for the preservation of wood, are recorded, besides others of more recent date. Of these processes many of them would, no doubt, prove effective, provided they could be carefully and economically applied. It is a difficult problem to treat timber in large quantities and meet with reasonable success.
The condition of the timber that is to be treated should always be considered. It should be sound. The trees should be cut during the season when the least amount of sap is flowing, which in this section of the country is in winter, say from November to February. It should not be treated in a frozen state, and it is advisable to shape the timber to the form in which it is to remain, before the treatment is applied. Seasoning is a very important factor. A few months of exposure to the air and sun will materially add to the durability of the wood. The process of treatment must be rigidly and faithfully performed. The opportunities for gross frauds which cannot readily be detected are many, and the numerous instances of record where cheating has been systematically carried on at works established for the purpose of treating timber, prove that the safest course for parties using preserved timber is to do the work themselves.
Three of the well-known processes for preserving timber are the following, viz. :—
Creosoting, creosote oil, so called, being the antiseptic.
Burnettizing, chloride of zinc being the antiseptic.
The creosoting process consists in injecting timber with hot creosote oil, in a closed cylinder, under pressure. It was invented in 1838 by John Bethel of England, who found that, by forcing at least seven pounds of creosote oil into each cubic