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THE BELL SYSTEM TECHNICAL JOURNAL, MARCH 1953 



either in sectors cut from discs or in boring samples. A summary of the 

 distribution of the retentions will be found in Table XV. 



If the overall retention data for post groups 1-11 are distributed in 

 2-pound retention lots the evidence falls into the categories represented 

 by Table XVI and Fig. 28. The inference is clear. One would expect a 

 satisfactory service life if the treatment retention by extraction, based 

 on the whole cross section, was at or above 8 pounds per cubic foot. This 

 is perhaps over-simplification. The variations shown in Tables XIV and 

 XV in the behavior of the posts in Groups 7 and 9, and possibly to a 

 certain extent in Group 8, disturb what looks like reasonably straight 

 reasoning. 



In order to extend the reasoning and provide another method of 

 interpretation, let it be assumed that the posts average 8 inches in di- 

 ameter at the ground line, which is close to their actual size. Calculation 

 of the pounds per cubic foot in the outer inch of such average posts is 

 shown in Table XVII. The influence of posts in groups 7 and 9 on the 

 averages is still evident. If there are differences in the efficiency of the 



Table XVI — Creosoted Southern Pine Test Posts 

 Condition at 1950 inspection by retention groups; 14-19 years in test; Gulf- 

 port test plot. 



* The distribution into retention lots was made on the basis of both weight 

 and extraction data, depending on information applicable to the eleven groups in 

 Table XIV. 



