William Smith (1769-1839)

Fossils have been long studied as great curiosities, collected with great pains, treasured with great care and at a great expense, and shown and admired with as much pleasure as a child's hobby-horse is shown and admired by himself and his playfellows, because it is pretty; and this has been done by thousands who have never paid the least regard to that wonderful order and regularity with which nature has disposed of these singular productions, and assigned to each class its peculiar stratum.

William Smith, notes written January 5, 1796

William Smith was born on March 23, 1769, into a family of small farmers. He received little formal education, but from an early age took an interest in exploring and collecting fossils in his native Oxfordshire in England. At the same time, he learned geometry, surveying, and mapping; at the age of eighteen he became an assistant surveyor, learning his trade from the master surveyor Edward Webb. Surveying required Smith to travel all over England; in 1794 he toured the entire country, and then he began to supervise the digging of the Somerset Canal in southwestern England, a job that lasted six years.

The job of surveying canal routes required detailed knowledge of the rocks through which the canal was to be dug. This led Smith to examine the local rocks very carefully. While doing this, Smith observed that the fossils found in a section of sedimentary rock were always in a certain order from the bottom to the top of the section. This order of appearance could also be seen in other rock sections, even those on the other side of England. As Smith described it,

. . . each stratum contained organized fossils peculiar to itself, and might, in cases otherwise doubtful, be recognised and discriminated from others like it, but in a different part of the series, by examination of them.
This is a statement of the "principle of faunal succession." The layers of sedimentary rocks in any given location contain fossils in a definite sequence; the same sequence can be found in rocks elsewhere, and hence strata can be correlated between locations. The principle is still used today, albeit with some alterations; for example, some fossil species may not be distributed over a wide area and therefore not be useful for long-range correlation.

In 1796, Smith was elected to the agricultural society at Bath, and began to discuss his ideas with others who were interested in rocks and fossils. He began to write notes and draw up local geologic maps. Smith was not the first to make geologic maps, but he was the first to use fossils as a tool for mapping rocks by their stratigraphic order, and not necessarily by their composition. Previous mapmakers had attempted to use the composition of rocks as indicators of their position in the stratigraphic column.

In 1799, Smith's employment with the canal-building firm came to an end. Smith then took a series of engineering jobs in several parts of Britain, and made a number of side trips all over England and Wales. His goal was to produce a complete geologic map of England and Wales, using the principles of fossil succession. Progress was slow, and money to finance the publication of such a map was hard to find. Finally, with the aid of 400 subscribers underwriting the project, production of the completed map began in 1812, and in 1815 the map was finally published.

Unfortunately, Smith's map was overlooked at first by the scientific community of the time; his humble origins and limited education were an obstacle to success in learned society. Not until the later part of his life was his contribution to geology appreciated in full. His contribution may best be summed up this way: In 1831, the Geological Society of London instituted the Wollaston Medal, its highest honor, awarded each year for outstanding achievement in geology. Smith received the first Wollaston Medal that same year. The geologist Adam Sedgwick, then President of the Society, presented the award to Smith with these words:

If, in the pride of our present strength, we were disposed to forget our origin, our very speech betrays us: for we use the language which he taught us in the infancy of our science. If we, by our united efforts, are chiselling the ornaments and slowly raising up the pinnacles of one of the temples of nature, it was he that gave the plan, and laid the foundations, and erected a portion of the solid walls, by the unassisted labour of his hands.