These figures are much the same as those given by Judd and Acree,0 except that their tar contained an unusual amount of water and their distillations were not carried to the coking of the pitch.

Table 1410 shows the boiling point and percentage volume of the fractions obtained on redistilling the total oils from a hardwood tar.

These figures on tar composition do not agree with those given by Klar11 in that the percentage of oils is much higher and the percentage of pitch correspondingly lower. This can be accounted for only by difference between the commercial hardwood tars produced in Europe and this country.


The charcoal is so complex that no single chemical constituent has ever been .separated and identified. It has been shown to contain methoxyl groups, however (see p. 60), and may be considered as consisting of still higher members of the series found in the tar and the pitch (the secondary charcoal constituents, see p. 53) deposited on the primary charcoal, which as the residue, of the ligno-cellulose decomposition is probably more complex than the original raw material.

Amount and Composition of Charcoal Produced at Different Maximum Temperatures.

Distillation temperature

Composition of charcoal

Yield of charcoal in percentage weight of dry wood



Oxygen, etc.

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