One of the most interesting problems in Indian Geology is the question of the age and mutual relations of the rocks containing coal in Bengal and Orissa. The fossils from the first named locality have long attracted notice in consequence of the great divergence shewn by them from European types of carboniferous vegetation, and of their identity with those from beds, also containing coal, in Australia. But these fossils being entirely vegetable, and fossil plants not having attracted, until very recently, the attention they deserved, except in the case of the true carboniferous flora of Europe and America, very little progress had been made towards ascertaining the geological relations of the Indian coal fields, until the commencement of the work of the Geological Survey of Mr. Williams. They were almost universally massed together as representatives of the carboniferous era, and the details of their geology were utterly unknown. They had not even received the attention which had been devoted to the rocks of Central, Western and Southern India.
Mr. Williams directed his attention rather to the economical than to the scientific questions presented to him, and he appears, in his examination of the Rániganj field, not only to have accepted the idea of the rocks being of true carboniferous age, but to have supposed that he found in the several beds composing them, representatives of the subdivisions recognized in Great Britain. But his observations on the geological relations of the beds among themselves are generally careful and accurate, his map is singularly correct, considering the very grave difficulties under which he worked, and although, partly perhaps owing to the small area which came under his observation, many essential circumstances escaped his notice, his accurate and trustworthy descriptions have since proved most valuable in shewing the relations of the rocks he surveyed to others which have since been examined.
The only other detailed geological observations are contained in
