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Outdoor Problems of the Householder: Coal-tar

Still better results can be obtained by soaking the timbers in the preservative for ten hours at ordinary temperatures. Coal-tar and crude petroleum are not as suitable for this purpose as creosote. This is liquid at ordinary temperatures, soaks into the timber readily and has strong antiseptic properties. Coal-tar creosote must be warmed slightly to liquefy COTTONWOOD The MAPLE ELM SYCAMORE HICKORY PIN OAK WHITE ASH LODGEPOLE PINE Sections of posts of various woods treated with creosote by the open-tank process. All the posts are drawn to the same scale, and are approximately 5 inches across. ely 5 inches across .

The black areas show the creosote penetration, which corresponds generally to the sapwood. (C. P. Willis.) various antiseptic coal-tar products are best suited to this purpose. Two or more coats should be applied hot.

A fifty gallon barrel of creosote will give 300 posts 3 coats for the butts and 2 for the tops.

Dipping. A somewhat better result may be secured by dipping the timbers so that the preservative can soak into the cracks and checks.

This plan takes less labor than painting but consumes more of the preservative, since the tank or barrel must be kept full to the proper depth. Either petroleum-tar or coaltar creosote may be applied by this it. All timber thus treated must be thoroughly seasoned and dried to get as much water as possible out of the cells and thus allow the oil to come in and take its place. The kinds of woods most suitable to this treatment are beech, cottonwood, the gums, pin and red oak, the pines, sycamore and tulip tree.

Impregnation with Creosote.-Undoubtedly the best method is the impregnation of timbers with creosote by the so-called "open tank process." This consists in heating the wood so as to expand its cells and drive out of them a portion of the air and water they contain and then emersing the timber in a preservative bath to cool. As the air and water remaining in the cells contract during the cooling process, a partial vacuum is formed. The cool preservative is then forced into this by atmospheric pressure. The illustrations show sections of different kinds of woods treated by this process.

Materials and Equipment. - To thoroughly impregnate posts and other farm timbers with creosote requires one or more barrels or tanks with some suitable provision for heating their contents. Two common creosote barrels may be used. Set these about 7 or 8 feet apart and connect them by a 3 or 4-inch iron pipe fitted with lock (jamb) nuts.

Build a fire under the middle of the pipe. Shield the sides of the barrel from direct heat by an apron or screen, preferably of some kind of metal as an old piece of sheet iron, tin or zinc. This outfit is inexpensive and, while the barrels are neither large nor deep enough for the best results and will usually leak after a few days, they answer well enough for a small number of posts or other timbers or shingles. A single barrel may be heated by means of a U made of 1½-inch pipe. Set the barrels in shallow boxes or on a platform provided with a gutter to carry off the oil to a neighboring tub, if the barrels suddenly spring a leak. But if many posts are to be treated, and especially if one desires to preserve timber for sale or do this class of work for others on a commercial basis, the best plan is to purchase a light (14 gauge) cylindrical galvanized iron tank. Such a tank 3 feet in diameter by 4 feet high, fitted with a U of 3-inch pipe, will cost about twelve or fifteen dollars.

With good care it will last indefinitely. Or a similar tank can be set in brick or masonry in such a way as to be heated from beneath like a set kettle. In addition, a rectangular tank for the cold bath about 8 feet long, 8 feet wide and 3 feet deep will be necessary if the entire post is to be immersed. Provision must be made to heat this, when necessary, to a temperature of about 100° or 120° F. to liquefy the creosote and cause it to penetrate freely. A thermometer reading to 250° F. is necessary. Preparation of Posts. - Select preferably round posts not exceeding 5 inches average diameter, of soft and porous wood as gum, pine, maple and the like. These are cheaper than hard wood, easier to treat, yet when properly treated are equally as durable. Do not attempt to treat hard woods which are naturally durable in contact with the ground such as cedar, locust, white oak and black walnut. Do not treat split posts having highly colored heart wood such as oak and yellow pine. The creosote will not penetrate hard wood and such posts will readily decay. In fact the advantage of this process is to make cheap posts of small size and soft wood, durable. Bevel the top of the post, preferably with an axe, so as to leave a smooth slanting surface to shed rain. Peel carefully. Remove even the papery inner bark, especially from pine and basswood. Season at least five weeks. Treat only when bone dry and not less than three or four days after exposure to heavy rains. To test posts when seasoning, weigh an average sample at intervals of five days. If the loss of moisture in that period is less than one pound per post of 5-inch average diameter, it may be safely used.

Treatment. This differs according to the kind of wood and the method employed. Soft wood absorbs more than hard wood. But, as a rule, limit the absorption to 0.4 gallon per post, if only the butt is treated, or 0.6 gallon, if the top is also impregnated. The best method is that which gives the deepest penetration in the shortest time.

To treat posts with creosote fill the tank th oil to such a point that the butts will be submerged 6 inches higher than they will stand in the OUTDOOR PROBLEMS OF THE HOUSEHOLDER 293 ground when set. Raise the temperature to 220° F. before putting in the post, and keep it there throughout the bath. If only one tank is used, the cold bath is brought about by removing the fire and leaving the Barrel Outfit. (C. P. Willis.) posts in the tank to cool until sufficient oil has been absorbed. More oil must be added from time to time to keep them submerged to the proper depth.

If two tanks are used, liquefy the oil in the cold bath by warming to a temperature of from 100° to 120° F.

Transfer the posts from the hot to the cold bath as quickly as possible.

Immerse to the same point as the post stood in the hot liquid. Add more oil from time to time to keep the posts immersed at that level. Or, if desired, only the butts may be heated but the whole post may be submerged in the cold bath. Thus the butts will receive a heavy, and the tops a light treatment. The cost varies with the kind of wood, cost of materials and method of treatment employed. It may be estimated at from twelve to fifteen cents per post exclusive of fuel and labor. If posts are properly creosoted they will last twenty years. Roughly speaking, this process will result in a net saving equal to the original value of the post.

The best results may be secured by treating the various woods about as follows, assuming that all posts are round, peeled, seasoned and average about 5 inches in diameter. Use the single tank treatment as follows for the following woods, viz., white ash, immerse in hot oil 5 hours, cooling oil 12 hours; cottonwood, hot oil 1 hour, cooling oil 12 hours; butternut, white elm and bitternut hickory, hot oil 6 hours, cooling oil 12 hours. Use the double tank treatment as follows: basswood, sweet (bay) magnolia and sycamore, hot oil 1 hour, cold oil hour; for beech, sweet (red) gum, pin oak and red oak, hot oil 1 hour, cold oil hour; for black gum, cotton (tupelo) gum, hot oil 1 hour, cold oil 1 hour; for loblolly and lodgepole pine, hot oil 1½ hours, cold oil 1 hour; for slippery elm, hot oil 14 hours, cold oil 1½ hours; for tulip tree, hot oil 2 hours, cold oil hour, for river birch, pitch pine and short. leaf pine, hot oil 3 hours, cold oil 1 hour; for sugar maple and scrub pine, hot oil 2 hours, cold oil 2 hours: for white willow, hot oil 4 hours, cold oil 1 hour; for red maple, hot oil 3 hours, cold oil 2 hours; for white poplar, hot oil 6 hours, cold oil 12 Taylor وہ Light iron tank heated by the pipe method of direct heating. (C. P. Willis.) hours. White willow requires an especially thorough seasoning. Preserving Shingles.-Shingles are sometimes preserved from warping and decay by painting or applying other preservatives with a brush.

But this process is not to be recommended. To dip the shingles separately in paint or coal-tar derivatives is a better method. But far more satisfactory results can be had by impregnating shingles with creosote by the above plan. Cheap pine shingles, clear and free from knots, can by this process be made superior to the best cedar shingles. And the life of the best shingles can be much prolonged. An apparatus similar to that used for posts may be employed or any kind of tank used in which one or more bundles of shingles can be immersed. But choose a deep tank rather than a shallow one to prevent loss of oil from volatilization. The exact treatment required for a given lot of shingles can be determined only by experiment. Weigh a sample bundle before and after treatment and time the treatment so that the shingles will absorb from twelve to thirteen pounds of oil per bundle or six gallons per 1,000 shingles. The cost should range from $1.25 to $1.50 per thousand. Have the hot bath relatively longer than the cold. Objections to this process are that creosote has a strong odor, contaminates cistern water and gets on shingle nails so that the workmen cannot hold them in their mouths. All these difficulties may be obviated by treating the shingles a few weeks in advance. Or a shingle nailing machine may be employed. The water may be diverted from the cistern for three or four days or a week; no taint will then be observed. The odor also passes away after a few days.

To color creosote shingles red or reddish brown, mix eight to twelve ounces of the required pigment ground in oil with an equal bulk of linseed oil and add to each gallon of the preservative. To color green, it is necessary to dip or paint the shingles. The green pigment is too expensive to mix with the creosote.

Other Timbers. - In addition to posts and shingles, the life of other timbers which come in contact with the soil or are exposed to moisture may be greatly increased by the above method. Among these may be mentioned foundations, sills, beams, wooden walks and planking, the lower portion of board fences, and all lumber used near the ground in sheds or barns. The treatment to be given is similar to that for posts.