Current Literature 605 



in an aggressive rather than a cooperative spirit, since there is no 

 great industry of the coiintry which is more vital to the general 

 welfare of the people; therefore an investigation of the above 

 character shotild be carried on in a constructive manner rather 

 than a destructive one. 



R .C. B. 



Relative Resistance of Various Conifers to Injection with Creosote. 

 By C. H. Teesdale. Bui. No. 101, U. S. Dept. Agr., Washington, 

 D. C, 1914. Pp. 43, ill. 



One of the most perplexing problems in timber preservation is 

 the varying resistance different woods and parts of woods offer 

 to the penetration of creosote. This is especially the case where, 

 instead of treating to refusal, a limited or partial treatment is 

 given. The average injection per cubic foot is obtained by divid- 

 ing the total amount of oil consimied in the process by the total 

 cubic contents of the material treated. This does not take accotmt 

 of the distribution of the oil. If just enough oil is injected to 

 give an average of, say, ten pounds per cubic foot, some pieces will 

 probably receive too much and others scarcely any. 



What is wanted is uniformity of treatment and to this end 

 extensive experiments have been made with a view of devising 

 some practical means of grading material before treating The 

 investigation reported on in this bulletin was concerned with the 

 relation between the structure of wood and the ease of injecting 

 with creosote. 



This appears to be an excellent piece of work very painstakingly 

 done, but imfortxmately it does not settle the question at issue. 

 In the words of the author, "No satisfactory theory has yet been 

 offered to explain the penetration of wood by creosote." It would 

 appear from the apparently conflicting results obtained that 

 penetrability is not dependent upon structure alone, but that 

 the chemical properties also are concerned. 



The following conclusions are given as a result of the experi- 

 ments: "1. Radial and longitudinal resin ducts penetrate inti- 

 mately the interior of the wood and thus form passages for the 

 preservative. Radial resin ducts were foimd to be especially im- 

 portant. Where these occiured the wood was usually penetrated 

 radially from one-fourth to three-fourths as far as longitudinally,. 



