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Bulletin 51: Report on the Condition of Treated Timbers Laid in Texas, February, 
1902. 
Results secured from various timbers which received preservative treatment and 
were then laid in an experimental track on the Gulf, Colorado and Santa Fe Railway 
near Pelican, Tex. — 
*Bulletin 70: Effect of Moisture on the Strength and Stiffness of Wood. Price, 15 
cents. 
The results of strength tests, principally on longleaf pine, spruce, and chestnut 
under compression parallel to grain, compression at right angles to grain, bending, 
and shearing. Factors are given for computing strength at 1° of moisture from the 
known strength at another. The character and behavior of the test pieces are shown 
by plates, and curves furnish graphic illustration of the relation of strength to moisture. 
Special studies of case-hardening, prolonged soaking, resoaking, and soaking followed 
by drying, as well as discussion of the fiber-saturation point, are included. 
Circular 12: Southern Pine: Mechanical and Physical Properties. 
Circular 15: Summary of Mechanical Tests on Thirty-two Species of American Woods. 
Three progress reports, of which the first two deal with the earlier series of timber 
tests conducted by the Division of Forestry. . 
Circular 38: Instructions to Engineers of Timber Tests. 
Circular 39: Experiments on the Strength of Treated Timber. 
A brief description of tests on treated timber, and of treating methods, begun at 
the St. Louis Exposition in 1904 and afterwards completed at the timber-testing 
station of the Service at Purdue University, Lafayette, Ind. The conclusions show 
that a high degree of steaming weakens wood; that zinc chlorid does not weaken 
wood under static loading, but may render it brittle under impact; and that the effect 
of creosote is not to weaken the wood, since it does not enter the cell walls, but appar- 
ently only retards seasoning. 
Circular 40: The Utilization of Tupelo. 
Circular 46: Holding Force of Railroad Spikes in Wooden Ties. 
Circular 47: Strength of Packing Boxes of Various Woods. 
Circular 48: Kiln-drying Hardwood Lumber. 
A brief statement of the problem of hardwood kiln-drying and a description of the 
kilns and processes in common use. f 
Circular 80: The Fractional Distillation of Coal-Tar Creosote. 
Circular 98: Quantity and Character of Creosote in Well-Preserved Timbers. 
Circular 101: The Open-Tank Method for the Treatment of Timber. 
Circular 103: Seasoning of Telephone and Telegraph Poles. 
Circular 104: Brush and Tank Pole Treatments. 
Circular 108: The Strength of Wood as Influenced by Moisture. 
The points brought out in Service timber tests to determine the comparative strength 
of wood when green or resoaked and when dry, with formulas for calculating the 
strength of the tested woods at various degrees of moisture and also the margin of 
safety required in using timbers where they will be exposed to moisture. A briefer 
statement of the facts and laws given in Bulletin 70. 
Circular 111: Prolonging the Life of Mine Timbers. 
A description of the different forms in which timber is used in mines and of the 
conditions which render the life of mine timbers so short; also of experiments In 
peeling and seasoning the timbers and in treating them by brush, in open-tanks, 
and in closed cylinders with creosote, cabolineum, and zinc chlorid, to determine 
-what method of preservative treatment will give the greatest service at the least 
expense. 
[Cir. 36] 
