57 



well as that of the creosote, so far-as that may appear profitable to the 

 main problems in hand. 



The test pieces for these experiments so far prepared are of Doug- 

 las fir sapling, about 5 inches in diameter and 6 inches long. They are 

 weighed with an accuracy of 0.1% and are now being treated with a 

 good creosote oil. The size of pieces is sufficient to absorb oil enough 

 for a complete analysis on being extracted, and yet small enough so 

 that the whole piece can be made into shavings and thus carried 

 through the experiment, which is necessary to obtain data of sufficient 

 accuracy for this study. One piece will be used for the immediate 

 extraction of its oil; two pieces will be placed in the air, and seven in 

 the Bay, for removal and inspection or analysis from time to time. 

 Sawdust representative of the wood used for the test pieces is being 

 Analyzed as to its composition, and some of the test pieces will be 

 analyzed after extraction of their oil, to determine whether treatment 

 and exposure have made any change in the wood composition. 



These two series should give information regarding the physical 

 and chemical nature of changes occurring in both the creosote and the 

 wood, under exposure of treated wood in air and water, respectively, 

 and regarding the relation of these changes to the creosote held in the 

 wood by absorption and adsorption, respectively. In particular, its 

 recorded compositions should permit a sufficiently accurate determina- 

 tion of the time-loss curves, both as to quantity and character, of 

 creosote lost from treated wood; which certain evidence seems to indi- 

 cate may be a critical factor in the explanation of the mechanism of 

 creosote protection. 



Analyses have been made by the Committee Chemist, of oils ex- 

 tracted from piles which had been in service for periods of from one 

 to thirty years. The short-service piles used for analysis had been 

 treated and driven in recent years, and analyses of the original oils 

 with which they had been treated were available. The long-service 

 piling used was from Oakland Long Wharf. It is recognized that the 

 methods of analyzing extracted oils so far used involve certain ele- 

 ments of possible error; but the analyses made by the Committee were 

 identical in method, and checked very closely in results, with those re- 

 ported to this Association in 1920. Comparison of the analyses made 

 by the Committee seems provisionally to indicate that the oils extract- 

 ed from piling "of as short service as one year had already lost light 

 oils and reached a composition closely similar to that shown by the 

 Long Wharf piling after 29 years' exposure. 



W'ork is already in progress in schedules 1, a, 2 and 3 above listed. 

 Work is projected in 1, fo, .) and 5, and mutual agreement is being 

 reached with respect to the details of the former. On the work already 

 started, it is believed that preliminary results of some value should be 

 available by June 30, 1922. 



