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The general results of his observation seem to have been these. He noted that the rocky masses of country in the western parts of England generally inclined to the east and south-east; that the red sandstones and marls above the coal measures passed beneath the lias, clay, and limestone, that these again passed beneath the sands, yellow limestones and clays, forming the table-land of the Cotswold Hills, while these in turn passed beneath the great chalk deposits occupying the eastern parts of England. He further observed, that each layer of clay, sand, and limestone held its own peculiar classes of fossils; and pondering much on these things, he at length came to the then unheard-of conclusion, that each distinct deposit of marine animals, in these several strata, indicated a distinct sea-bottom, and that each layer of clay, sand, chalk, and stone, marked a distinct epoch of time in the history of the earth.

This idea took firm possession of his mind, and he could talk and think of nothing else. At canal boards, at sheep-shearings, at county meetings, and at agricultural associations, 'Strata Smith,'

as he came to be called, was always running over with the subject that possessed him. He had indeed made a great discovery, though he was as yet a man utterly unknown in the scientific world. He proceeded to project a map of the stratification of England; but was for some time deterred from proceeding with it, being fully occupied in carrying out the works of the Somersetshire coal canal, which engaged him for a period of about six years. He continued, nevertheless, to be unremitting in his observation of facts; and he became so expert in apprehending the internal structure of a district and detecting the lie of the strata from its external configuration, that he was often consulted respecting the drainage of extensive tracts of land, in which, guided by his geological knowledge, he proved remarkably successful, and acquired an extensive reputation.

One day, when looking over the cabinet collection of fossils belonging to the Rev. Samuel Richardson, at Bath, Smith astonished his friend by suddenly disarranging his classification, and re-arranging the fossils in their stratigraphical order, saying -"These came from the blue lias, these from the over-lying sand and freestone, these from the fuller's earth, and these from the Bath building stone." A new light flashed upon Mr. Richardson's mind, and he shortly became a convert to and believer in William Smith's doctrine. The geologists of the day were not, however, so easily convinced; and it was scarcely to be tolerated that an unknown land-surveyor should pretend to teach them the science of geology.

But William Smith had an eye and mind to penetrate deep beneath the skin of the earth; he saw its very fibre and skeleton, and, as it were, divined its organization. His knowledge of the strata in the neighbourhood of Bath was so accurate, that one evening, when dining at the house of the Rev. Joseph Townsend, he dictated to Mr.

Richardson the different strata according to their order of succession in descending order, twenty-three in number, commencing with the chalk and descending in continuous series down to the coal, below which the strata were not then sufficiently determined.

To this was added a list of the more remarkable fossils which had been gathered in the several layers of rock. This was printed and extensively circulated in 1801.

He next determined to trace out the strata through districts as remote from Bath as his means would enable him to reach. For years he journeyed to and fro, sometimes on foot, sometimes on horseback, riding on the tops of stage coaches, often making up by night-travelling the time he had lost by day, so as not to fail in his ordinary business engagements. When he was professionally called away to any distance from home - as, for instance, when travelling from Bath to Holkham, in Norfolk, to direct the irrigation and drainage of Mr. Coke's land in that county - he rode on horseback, making frequent detours from the road to note the geological features of the country which he traversed.

For several years he was thus engaged in his journeys to distant quarters in England and Ireland, to the extent of upwards of ten thousand miles yearly; and it was amidst this incessant and laborious travelling, that he contrived to commit to paper his fast-growing generalizations on what he rightly regarded as a new science. No observation, howsoever trivial it might appear, was neglected, and no opportunity of collecting fresh facts was overlooked. Whenever he could, he possessed himself of records of borings, natural and artificial sections, drew them to a constant scale of eight yards to the inch, and coloured them up. Of his keenness of observation take the following illustration. When making one of his geological excursions about the country near Woburn, as he was drawing near to the foot of the Dunstable chalk hills, he observed to his companion, "If there be any broken ground about the foot of these hills, we may find SHARK'S TEETH;" and they had not proceeded far, before they picked up six from the white bank of a new fence-ditch. As he afterwards said of himself, "The habit of observation crept on me, gained a settlement in my mind, became a constant associate of my life, and started up in activity at the first thought of a journey; so that I generally went off well prepared with maps, and sometimes with contemplations on its objects, or on those on the road, reduced to writing before it commenced. My mind was, therefore, like the canvas of a painter, well prepared for the first and best impressions."Notwithstanding his courageous and indefatigable industry, many circumstances contributed to prevent the promised publication of William Smith's 'Map of the Strata of England and Wales,' and it was not until 1814 that he was enabled, by the assistance of some friends, to give to the world the fruits of his twenty years'