38 DEPARTMENTAL REPORTS. 



tannin in treatment. A field test of the strength, of zinc chlorid 

 solution was devised, and preliminary work was done on the methods 

 of analyzing and extracting creosote. This included the devising 

 of a new method of estimating tar acids, comparative distillations, 

 and tests to determine the best solvent for extracting creosote from 

 treated timbers. A study of wood distillation, begun during the year, 

 promises a new means of utilizing much of the present waste in 

 lumbering. 



A pulp-testing laboratory was installed at Boston, Mass., to investi- 

 gate the paper-making possibilities of woods hitherto unused for pulp, 

 especially of certain species abundantly supplied by the forest re- 

 serves. An anti-stain process of treating white pinfe sapwood in 

 Michigan was investigated and found effective with proper piling. 



TIMBER TESTS. 



In all 12,033 mechanical tests were made, and as many moisture 

 determinations, as against 8,210 last year. Each test involved an 

 average of 35 measurements, a description and sketch of the stick 

 before and again after the test, and the necessary computations and 

 drawings. The tests were made at the various laboratories as follows : 

 Yale, 1,856; Charleston, 190; Berkeley, 2,496; Purdue, 6,156; Port- 

 land, 259; Eugene, 872; Seattle, 204. 



Tests were completed during the year upon loblolly pine to show 

 the influence of sapwood and knots on the strength of structural tim- 

 ber; on red fir (in cooperation with the University of California); 

 on Minnesota tamarack and Norway pine in large and small pieces; 

 on the holding force of railroad spikes in treated and untreated lob- 

 lolly pine and white and red oak ; on the effect of preservative treat- 

 ment on loblolly pine ; on strength as affected by the speed at which 

 a load is applied ; and on the influence of defects upon loblolly pine 

 harvester poles, which led to improved specifications. 



There are still in progress tests of the strength of California euca- 

 lypts (in cooperation with the State of California) to learn whether 

 the wood can be used in place of such structural timbers as hickory 

 and oak; of the strength of red fir as modified by knots and other 

 defects, rate of growth, and sapwood ; of western hemlock from 

 various localities of the Northwest, including Alaska, and of untried 

 woods from the forest reserves ; of the effect upon strength of various 

 methods of seasoning; of the bending of beams under constant loads 

 for long periods; of the behavior under a blow of buggy spokes, 

 axles, and wagon tongues; of resistance of street-paving woods to 

 abrasion, indentation, and water absorption (in cooperation with the 

 Office of Public Roads) ; of the bearing value of different forms of 

 washers on wood stringers, and of the relative strength of live oak 

 and black locust insulator pins. 



Reports submitted for publication and now in press were : " In- 

 structions to engineers of timber tests," " Effect of moisture on the 

 strength and stiffness of wood," and " Experiments on the strength of 

 treated timber." Reports were also prepared on the strength of 

 various woods in the form of boxes, the strength of Philippine woods, 

 the strength of timber treated by a nonsteaming process, the strength 

 of loblolly and pitch-pine mine props, the strength of common and 

 hardy catalpa, and the strength of African yew and red cedar. 



