68 



BCTLLETIN 1036, V. S. DEPARTMEI^T OF AGRlCIILTUKE. 



Table 18. — Distillation of oil before and after evaporation. 





Creosote 



Creosote 



Temperature 



before 



after 



(degrees C). 



evapo- 



evapo- 





ration. 



ration. 





Per cent. 



Per cent. 



Up to 210.. 



2.2 



0.2 



210 to 235... 



23.3 



0.8 



235 to 270... 



24.1 



14.1 



270 to 315... 



17.5 



32.0 



315 to 355... 



17.1 



27.3 



Residue 



17.5 



25.6 



The actual loss produced by evaporation was 41.5 per cent. The 

 loss calculated from the pitch residue was 43.2 per cent. The loss 

 calculated from the residue above 270° C. was 41.1 per cent. By 

 the pitch-residue method, the maximum difference is 1.7 per cent, 

 and the maximum difference by residue above 270° C. is 0.4 per cent. 

 As the data used in both cases were the same, these differences are 

 due to the method of calculation rather than to any error in analysis. 



In most cases it is impossible to obtain records of any kind that 

 will show the composition of the creosote used in the treatment of 

 old timbers. Two such records are fm-nished by the pole lines of 

 the American Telephone & Telegraph Co. This company has a 

 number of analyses of the original oils used, from which a fair average 

 may be obtained. One line, the Washington-Norfolk line, was 

 erected in 1897; the other, the Montgomery-New Orleans line, was 

 erected in 1899. Five poles in the Washington-Norfolk line were 

 removed in 1906 and one in 1908 for analysis. One pole from the 

 Montgomery-New Orleans line was removed in 1908 for analysis. 



The analysis of the creosote before treatment was obtained from 

 the American Telephone & Telegraph Co., which makes the following 

 report : 



The original reports of the analysis are in our files and from which we have prepared 

 the following table as indicating the average of the oil used in the treatment of the 

 poles for that line. It is, of course, impossible to associate the poles under test with 

 any particular analysis of oil. 



Table 19. — Average of tests of dead oil of coal tar used in treating poles. 



DISTILLATES. 



Per cpnt. 



Loss, water, etc. , 170° 1 



170° to 205° 2 



205° to 210° 4 



210° to 235° 45 



235° to 240° 7 



240° to 270° 16 



270° to 316° 9 



Residue above 316° 16 



100 

 Twenty-eight analyses were available for the above average. 



