On the four visible ingredients in banded bituminous coal; studies in the composition of coal, No. 1

Even after a century of investigation coal remains a complex mass of which the component parts can neither be handled nor separately identified. Many authors have recognised a variety of plant remains in coal, and the specific identification of these organisms and tissues has made good progress; but such work is truly palæontological, and the points of interest in it are the organisms and not the coal mass of which they form a part. From another point of view coal is a rock, but, unlike most rocks, the nature and orientation of its component parts are scarcely known. One of the most distinguished of living geologists once said to me that he would like to have available about microscopic sections of coal rationalised data comparable with those already obtained by petrologists about thin rock sections. The present paper is a contribution in that direction. It is an attempt to present systematically certain observations made incidentally in the course of the joint researches Dr. R. V. Wheeler and I have been follow­ing out on various other aspects of the hydra-headed “coal-problem.”