. Electric railway journal . reclearly shown in the accompanying curves, which aretaken from Bulletin 84 of the United States ForestService. These curves cover the usual practice in airseasoning, but in dry air the process goes on for a muchlonger period than shown, although the loss of waterafter the first few months is, speaking comparatively,very slow. If, instead of piling in the air, the poles are firstsoaked for a few weeks, it is found that seasoning aftertheir removal from the water proceeds at a much fasterrate than in the case of the entirely air-dried ones; thisis due to the fact th
. Electric railway journal . reclearly shown in the accompanying curves, which aretaken from Bulletin 84 of the United States ForestService. These curves cover the usual practice in airseasoning, but in dry air the process goes on for a muchlonger period than shown, although the loss of waterafter the first few months is, speaking comparatively,very slow. If, instead of piling in the air, the poles are firstsoaked for a few weeks, it is found that seasoning aftertheir removal from the water proceeds at a much fasterrate than in the case of the entirely air-dried ones; thisis due to the fact that much of the gum and mineralmatter is washed out, giving the contained water a moreporous material through which to be evaporated. Reduction in Weight Should Be Considered While the chief purpose of seasoning is to cutdown as far as possible the food supply of the fungicausing decay, and in case of preservative treatment,to put the wood in condition to absorb the maximumamount of the chemical used, the reduction in weight,. and consequent savingin freight charges, isno small matter, rang-ing, as it does, fromabout 16 per cent in thecase of chestnut tonearly 50 per cent for Western yellow pine. In theexperiments described in Forest Service Bulletin 84 theresults were as follows: Length of Weight of Pole Treatment Size of Pole Pounds Loss of Y\ < ijdt Spee; Months Top Length Green Seasoned Pounds Per Cent Chtstnut 4 to 6 7 in. 30 ft. 1120 940 180 16 Northern white 6 to 12 7 in. 30 ft. 581 440 141 24 Western red 3 to 5 8 in. 40 ft. 902 683 219 24 Southern white 3 to 8 7 in. 30 ft. 768 540 228 30 Western yellow pine 3 to 9 8 in. 40 ft. 1697 862- 835 49 These figures are for commercial air seasoning; alonger treatment under the same conditions of reason-ably free circulation of air about the poles will resultin still further loss of water, but at a rate which as arule does not warrant it; kiln drying removes morewater in very short time, and if immediately followed
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