EVALUATION OF WOOD PRESERVATIVES 



433 



creosote 5286B at 9.3, 9.7 and 12.5 pounds (see Table X) apparently have 

 not operated to increase the average life of the group treated with this 

 oil as much as appears to be the case in the group treated with creosote 

 5283. The difference in behavior at the 6-7 year interval of the stakes 

 that were treated by a full cell process with treating solutions made by 

 dissolving the creosote in toluene is even more marked than it is in the 

 empty cell groups. 



The average per cent condition of the stakes over the 9-year test 

 period up to 1950 is shown in Table XII. Data are included on the 

 number of stakes in each lot, and on the average treatment retention in 



34567 89 10 



TREATMENT RETENTION IN POUNDS PER CUBIC FOOT 



Fig. 17 — Distribution of ratings in relation to retention by weight at treat- 

 ment; creosote No. 5283, full-cell treatment (toluene dilution), six years exposure. 



