952 EXPERIMENT STATION RECORD. 



less than unsoaked wood but its compression strength is also less than that of 

 wood in the air-dry condition. 



The use of wood soaked in fresli water is strongly recommended for artistic 

 and industrial purposes, whei'eas wood soaked in salt water is only recommended 

 for use where warping in a changeable moist atmosphere is of less consequence 

 than the durability of the wood. Salt water soaked wood should be completely 

 air-dried before being used and should not be used in fine woodwork, as the salt 

 in the presence of moisture is apt to cause rust streaks upon coming in contact 

 with iron. 



The seasoning' and preservative treatment of arbor-vitae poles, C. S. 

 Smith {U. »S'. Dcpt. Aijr., Furest -S'crr. Circ. 136, i>i). 29, figs. 7). — An account 

 is given of experimental work conducted by the Forest Service in cooperation 

 with the American Telephone and Telegraph Company, with the view of inves- 

 tigating the various methods of seasoning and preserving arbor-vitaj poles to 

 increase their length of service. 



The seasoning test included 446 poles. These were peeled immediately after 

 being cut and skidded in the woods in single tiers about 2 ft. above the ground. 

 Each pole was numbered and weighed and its circumference at 6 and 30 ft. 

 from the butt recorded. These measurements were again taken after a long 

 period of seasoning, and a series of circumference measurements was also made 

 at the butt and at successive 5-foot points to determine the volume, weight per 

 cubic foot, and taper of an average pole. Note was also made of checking 

 during seasoning. 



The data secured are presented in several tables and diagrams and show the 

 meteorological conditions in northern Michigan during the entire i^eriod of 

 seasoning, the average volume of poles, the relation of moisture content to 

 seasoning time, the weight and moisture content both by monthly and by 

 seasonal cuts, the percentage of freight weight saved by seasoning, the relative 

 economy of various cutting seasons and shipping times, the effect of rate growth 

 upon seasoning, shrinkage, checking, and action of fungi and insects, and the 

 form, age, and condition of arbor-vitje poles. 



At the conclusion of the seasoning experiment several methods of treating 

 the pole butts were tried, including brush treatments with carbolineum and 

 creosote and open-tank treatments with creosote. Records were kept of dura- 

 tion of treatment, temperature of oil, and depth of penetration. In addition to 

 the 446 seasoned poles 43 green ones were treated, together with 3 tamarack 

 poles. The data secured from this work are given and discussed and several 

 conclusions are reached relative to the methods of seasoning and treating. The 

 poles included in the experiment are to be set in an experimental line and 

 further tested. 



The creosoting' of home-grown timber, W. B. Havelock (Quart. Jour. For- 

 estry, 1 (1907), No. Jf, PI). 350-353). — Tabular results are given of a recent 

 experiment conducted by the author (see also E. S. R., 18, p. 148), in which 

 tests were made to ascertain the absorption of creosote oil by 27 kinds of 

 round timber. The timber was felled in December, 1906, cut into 8 ft. lengths 

 and allowed to season outside protected from the rain until May 29. Previous 

 to the creosoting a vacuum of 9 lbs. was maintained in the cylinder for some 

 time, after which the oil was injected and kept under a pressure of 85 lbs. 

 per sq. in. for 3 hours. The tabulated data show the species of timber treated, 

 the number of pieces, weight previous and subsequent to barking and before 

 and after creosoting, total increase in weight, and weight of creosote oil absorbed 

 per cubic foot, with notes on the penetration in each case. 



A primer of wood preservation, W. F. Sherfesee (U. 8. Dcpt. Agr., Forest 

 Serv. Circ, 139, pp. 15). — This circular treats of the importance and use of 



