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rudiments of life develop into its highest consummations.

To those unacquainted with the results of geological investigation the history of the mountains as deciphered in the rocks seems almost incredible.

The recently published sections of the Himalaya, due to H. H. Hayden and the many distinguished men who have contributed to the Geological Survey of India, show these great ranges to be essentially formed of folded sediments penetrated by vast masses of granite and other eruptives.  Their geological history may be summarised as follows

The Himalayan area in pre-Cambrian times was, in its southwestern extension, part of the floor of a sea which covered much of what is now the Indian Peninsula.  In the northern shallows of this sea were laid down beds of conglomerate, shale, sandstone and limestone, derived from the denudation of Archaean rocks, which, probably, rose as hills or mountains in parts of Peninsular India and along the Tibetan edge of the Himalayan region.  These beds constitute the record of the long Purana Era[1] and are probably coeval with the Algonkian of North America.  Even in these early times volcanic disturbances affected this area and the lower beds of the Purana deposits were penetrated by volcanic outflows, covered by sheets of lava, uplifted, denuded and again submerged

[1] See footnote, p. 139.

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beneath the waters.  Two such periods of instability have left their records in the sediments of the Purana sea.

The succeeding era—­the Dravidian Era—­opens with Haimanta (Cambrian) times.  A shallow sea now extended over Kumaun, Garwal, and Spiti, as well as Kashmir and ultimately over the Salt Range region of the Punjab as is shown by deposits in these areas.  This sea was not, however, connected with the Cambrian sea of Europe.  The fossil faunas left by the two seas are distinct.

After an interval of disturbance during closing Haimanta times, geographical changes attendant on further land movements occurred.  The central sea of Asia, the Tethys, extended westwards and now joined with the European Paleozoic sea; and deposits of Ordovician and Silurian age were laid down:—­the Muth deposits.

The succeeding Devonian Period saw the whole Northern Himalayan area under the waters of the Tethys which, eastward, extended to Burma and China and, westward, covered Kashmir, the Hindu Kush and part of Afghanistan.  Deposits continued to be formed in this area till middle Carboniferous times.

Near. the close of the Dravidian Era Kashmir became convulsed by volcanic disturbance and the Penjal traps were ejected.  It was a time of worldwide disturbance and of redistribution of land and water.  Carboniferous times had begun, and the geographical changes in

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the southern limits of the Tethys are regarded as ushering in a new and last era in Indian geological history the Aryan Bra.