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,
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:
. . . 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.
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.