Part IV. J R. S. Pearson: Antiseptic Treatment of Timber. Ill 
good antiseptic solution. It commences to boil at 221°C. and contains 
oil boiling at over 360°C; and therefore contains no Phenol or Cresol oils, 
which is probably an advantage when considering oils for use in the hot 
climate prevailing in India. Avenarius Carbolineum oil contains even 
higher boiling point oils than Green oil, as only 48 drops of the former 
against 51 drops of the latter, passed over at 300°C. Green oil, on the 
other hand, contains 5 per cent, of acids against 1-51 per cent, in Avenarius 
Carbolineum. 
Solignum contains a high percentage of lighter oils, probably of a 
Phenolic and Cre'solic character and is therefore highly antiseptic. It 
also contains a fair proportion of heavy oils, for at least half the oil 
tested remained in the flask after the temperature had been raised to 
over 300°C. 
The Liquid Fuel oil shows relatively lower boiling points than 
Coal-tar creosotes which, together with their low toxic value, would pro¬ 
bably debar it from being used unmixed with a creosote oil. 
The mixture of Avenarius Carbolineum and Liquid Fuel gives a quite 
satisfactory analysis, indicating that the mixture may be of great value 
fpr treating timber under Indian conditions, especially as it reduces 
the cost of the solution, thus either permitting greater quantities of the 
oil being used or, if that is not desired, considerably reducing the cost of 
treatment. 
The analyses given above are for oils used in the experiments carried 
out and described in Parts III, IV and V ; below are given some standard 
specifications, fixed for creosote oils used in Europe and America. 
The following is the specification for creosote oil fixed by the London 
North-Western Railway :— 
18 per cent, between ...... 205°C. and 245°C. 
12 .,. 245°C. and 270°C. 
22 . 270°C. and 320°C. 
15 „. 320°C. and 420°C. 
33 „ residue above . . . . . 420°C. 
Elsewhere in this note reference has been made to 160,000 creosoted 
Douglas Fir sleepers being imported into India from British Columbia. 
The creosote to be used was to conform to the following specifications :— 
(1) Completely liquid at 38°C. 
(2) Specific Gravity at 38°C.—1-03. 
(3) Only 8 per cent, by volume of tar acids to be soluble in a Caustic 
Soda solution. 
(4) No distillate below 200°C., not over 5 per cent, below 210°C., 
not over 25 per cent, below 235°C., and the residue above 
355°C., if it exceeds 5 per cent, in quantity, should be soft. 
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