Creosoted timer (1900) (14596158397)

Identifier: creosotedtimer00norf (find matches)
Title: Creosoted timer
Year: 1900 (1900s)
Authors: Norfolk creosoting company. (from old catalog)
Subjects:
Publisher: (n. p.)
Contributing Library: The Library of Congress
Digitizing Sponsor: The Library of Congress



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which willbe an insufficient space for receiving the preservative. If,on the other hand, the operation is carried on at too high atemperature, or for too long a time, the resinous portion ofthe bundles of fibrillse will be softened and the wood loseits elasticity in just the proportion that the coherence ofthe fibrillae is lessened. The temperature should never beless than 100° C. or exceeding 130° C. Of the two possiblemethods for the removal of the undesirable portions of thetimber, exposure to currents of dry air, and steamingunder pressure with an after drying in a vacuum, the latteris now the universal practice. While the first-named planmay seem the more rational, and the one least likely tomodify injuriously the physical structure, such is not thecase. Under proper manipulation, a more thorough desic-cation, without harmful change of the organic structure, canbe accomplished in twelve hours less by the latter process,than ig 0ver possible witb air drying which, under the most
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ITS PREPARATION AND USES 35 favorable circumstances, is a long-drawn-out operation, andcannot do more than extract the water from that portion ofthe sap which has not yet reached the semi-soHd stage, thusleaving in the tissues of the wood a very considerableamount of resinous matter which occupies space that shouldbe ready to receive the creosote oil. The consequence ofthis is a failure of the oil to reach many of the interfibrouspassages, which are either left empty or are filled w^ith thegelatinous part of the half-matured growth cells in w^hichare to be found the conditions that make putrefaction possi-ble. In order to remove the sap from wood, it is first neces-sary to vaporize it and then to bring about such externalcircumstances which shall allow^ outflow of all gaseous mat-ter from the interior of the wood. In order to vaporize thesap it is necessary to break down the walls of the cells con-taining the liquid and semi-liquid substances. This isreadily accomplished through the a