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true principles of draining ; and fortunately many practical works of 

 this kind were carried on under his immediate inspection. 



In 1787 (when eighteen years of age) he was employed in survey- 

 ing and inclosing extensive tracts of common-land : this gave him a 

 further insight into the minutest modifications of structure in his native 

 country ; and within the two next years his surveys extended beyond 

 the oolite hills into the plain of the new red sandstone. The regular 

 stratification of the lias and the peculiarities of the red ground, at 

 that time new to him, made a lasting impression on his mind. Carry- 

 ing with him his acquired habits of accurate observation, he continued 

 his surveys (during 1790) to the coast of Hampshire, and to the 

 country round Salisbury and Bath ; and he became gradually familiar 

 with the outline of the chalk downs, and the external characters of 

 large agricultural districts. In 1791, while employed in making ex- 

 tensive surveys in a part of Somersetshire, he remarked the identity 

 of the red marl and lias of that county with the corresponding for- 

 mations of Gloucestershire, and recognized their discordant position 

 on the coal measures. During the same year he made several detailed 

 sections of the coal strata; collected fossil plants which he found cha- 

 racteristic of particular beds in his sections ; and remarked that none 

 of the many fossils of the lias were found either in the coal strata or 

 the red marl : and at this time he also began to make practical obser- 

 vations and inquiries with a view of ascertaining the range and extent 

 of the successive deposits, and the reality of a general line of dip to- 

 wards the east, of which he had already seen so many local instances. 



I think these facts of great importance, as they contain the germ 

 of all Mr. Smith's future discoveries. And we must bear in mind — that 

 his attention was distracted by the duties of a laborious profession — 

 that he had barely reached the age of manhood — and that he had not 

 received a glimmering of direction in his general speculations. 



In the course of the two following years, while continuing the duties 

 of a surveyor and civil engineer, he became gradually acquainted with 

 all the minute facts of stratification in the country round Bath : and 

 for the purpose of bringing to the test the inquiries suggested by his 

 surveys in 1791, he made two transverse sections along the lines of 

 two parallel valleys intersecting the oolitic groups (determining the 

 actual elevation of these lines by means of levels carried from the 

 Somerset Coal Canal); and ascertained that the several beds, found 

 in the high escarpments around Bath, were brought down by an 

 eastern dip, in regular succession, to the level of his lines of section. 

 During these two years Mr. Smith was in the constant habit of ma- 

 king collections of fossils, with strict indications of their localities ; and 

 in completing the details of his transverse sections, he found, where 

 the beds themselves were obscure, that he could by organic remains 

 alone determine the true order of succession. During this period he 

 also extended his surveys through the Cotteswold Hills, and became 

 acquainted with the general facts of the range of the oolitic escarp- 

 ment towards the North of England. 



In the year 1794? he crossed the whole series of formations, and 

 marked their escarpments between Bath and London ; and afterwards 



