ABSTRACT
Since coal is derived chiefly from vegetal matter, it consists mainly of the elements that go to compose plants, but it differs from plants in composition in as much as certain proportions changed during the fermentation and metamorphic processes that have caused the formation of coal. As the plants accumulated under water, some silt also settled along with them. Thus at a later stage, some mineral matter got mixed with the coal as it formed. In addition to the plant and mineral matter, an appreciable amount of animal matter may have been imprisoned in the coal and this may have caused a variation from normal composition, especially in nitrogen and phosphorous content.
