The preliminary work on the decomposition of various organic
materials indicated that graphite, coal, and certain kinds of charcoal,
if present in soils, would be found in the part not attacked by hydrogen
peroxide. However, it is not to be expected that graphite, widely
distributed in small quantities, would occur in anything more than
traces in most soils. Coal particles would be restricted to coalbearing
regions. Because of the prevalence of forest fires, charcoal
might be present in almost all soils. The decomposability of charcoals,
however, is evidently variable