COAL-TAR AND WATER-GAS TAR CREOSOTES. 
63 
the creosotes tested. Beyond the time of 304 days the blocks gained 
in weight, probably because of the absorption of moisture. The 
results of these tests are plotted in figure 31c, in which the ordi- 
nates are the percentages distilling at 270° C. and the abscissas are 
90 

• 
80 
• 
• 
O 
• 

o io 
N 
4 
1 ' A 
P 
o 
£ 90 
» L 
• 
o$ 
• 
» 
OS 
• 
© 
o 
• 
• ■ 
• 
B 
i > 
70 80 10 
PERCENTAGE LOSS 
Fig. 31.— Relation between the loss by evaporation and the per cent of 
the oil volatile below 270° C. 
A. Loss of coal-tar creosote by evaporation from open pans. 
B. Loss of coal-tar creosote by evaporation from creosoted wood. 
C Loss of coal-tar creosote by evaporation from pans and creosoted 
wood. Lots — Open pans. Circles — Maple blocks. Double 
circles — Pine blocks. 
D. Loss of water-gas tar creosote by evaporation from open pans. 
the percentages of loss by evaporation. The three points lying in 
the lines parallel to the abscissae are obtained by using the same 
creosote in the three different methods of test. 
