EVALUATION OF WOOD PRESERVATIVES 



467 



Calculated losses in the outer 1 inch of these two posts — • assuming 

 8-inch diameter — are 64.0 and 70.3 per cent, respectively, or an average 

 of 67.2 per cent; and this figure corresponds very closely with the four- 

 year loss figure of 69.2 per cent calculated for the empty cell posts in 

 Table XXI. The posts represented in Tables XXII and XXIII were 

 obviously treated to retentions that were too low to be effective; but 

 they illustrate what is likely to happen when too low retentions of highly 

 volatile light creosotes are used in wood in contact with the ground. 



Bateman discusses a laboratory experiment to determine creosote 

 losses, over a 70-day period from pieces of round post sections, 5 inches 

 in diameter and 2 feet long; and he extends his comparison to data 

 derived from experiments conducted for the San Francisco Marine Piling 

 Commission. He reports the following treatment data for the three creo- 

 sotes involved: 



1. 18 Ib/cu ft of a creosote with 92 per cent distilling below 275°C; 



2. 10 Ib/cu ft of a creosote with 40 per cent distilling below 275°C ; and 



3. 27.5 Ib/cu ft of a creosote with 42 per cent distilling below 275°C. 

 His comparative loss data are condensed in Table XXIV. 

 Waterman and Williams report creosote losses based on periodic 



extractions of comparable lots of specimens from treated round southern 

 pine saplings exposed in the Gulf port test plot. Their data are condensed 



Table XXIV — Creosote Losses 

 By weight, from round southern pine post sections*, and from pile sections- 

 Madison (Bateman) data. 



■^ Five inch diameter posts, 2 feet long 

 t See text for group and creosote data. 



i; 



