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THE BELL SYSTEM TECHNICAL JOURNAL, MARCH 1953 



tions, and with the assumptions made. About the difference in the quali- 

 tative changes that take place during creosote losses there is much, but 

 not enough, information. 



An Interpretation of Creosote Losses 



Frosch,^^ in describing certain physical characteristics of the Fulvveiler 

 oils, states that they may be considered as truly viscous solutions in 



Table XXXI — Creosote Losses, by Weight, from Impregnated 



Filter Paper, and Calculated Increase in Residue 



BTL (Boving) data 



* Assuming that all loss occurs in fraction below 355°C. 



Table XXXII — Theoretical Changes in Creosote 

 Loss of volatile fractions by evaporation; amount remaining of total fraction 

 below 355°C. 



* Time periods 1 and 2 represent exposures that would result in the per cent 

 losses determined from Boving's 7 and 14 day tests, respectively. See text. 



