Geotimes is now


Customer Service
Geotimes Search

GeoMarketplace Link

EARTH magazine cover


Lifting the Veil On History’s Unsung Earth Scientists
Geotimes staff

A Renaissance artist, two U.S. presidents, a First Lady and a groundbreaking physician all shared a common interest — geology. Granted, at the time some of them were studying the world around them, the term “geology” did not even exist or was not well-known, but their interests in understanding the planet’s systems were manifold, whether collecting fossils or surveying a mine. Here, we take a look at these famous people who were little-known geoscientists — surely only a few among many — and their surprising contributions to the earth sciences.

Leonardo da Vinci: Rocking the natural sciences world
Thomas Jefferson: Founding father of American paleontology
Edward Jenner: From speckled monster to sea monster
Herbert and Lou Hoover: A dynamic and geologic pair

Leonardo da Vinci: Rocking the natural sciences world

The Mona Lisa is arguably Leonardo da Vinci’s most famous painting and is widely recognized around the world. That said, try to describe the painting without looking at it. The figure’s ambiguous “smile” and wandering eyes probably come to mind first. But “can you remember what’s in the background?” asks Cherry Lewis of the University of Bristol in the United Kingdom. “Nobody can, really,” she says.

Close inspection of the background of Leonardo da Vinci’s famous painting the Mona Lisa reveals jagged rocks and rushing water. That da Vinci’s paintings and notes show such close attention to nature’s details reflects the artist’s interest in geology and other sciences. Image is courtesy of the Louvre Museum.

Behind the figure, torrents of water cascade down between dark, jagged rocks, before flowing into a river that sweeps across the back of the painting and passes under a bridge. The background is straight from the Arno Valley in Tuscany, where da Vinci grew up, according to “The Mona Lisa,” the third, final episode of a 2004 BBC television series about da Vinci to which Lewis contributed. But the scene is also a reflection of one of da Vinci’s keen, yet lesser-known interests — geology.

Of course during da Vinci’s lifetime, from 1452 to 1519, the term “geology” did not yet exist: Chemistry, biology, physics and Earth were studied together within the natural sciences. “They didn’t distinguish one from another in the way that we do today,” Lewis says. Da Vinci excelled at all the natural sciences, as well as engineering and art, she says. “That was what was so fantastic about him.”

In fact, it was da Vinci’s work engineering bridges and canals that led him to profound realizations about water and erosion — that land gradually becomes uplifted, and rivers act to erode rock and cut down through sediments, forming valleys and mountains. He recorded evidence for the process in the Alps, where rock layers in the mountains on each side of a river appeared to match, wrote Stephen Jay Gould, the late paleontologist and evolutionary biologist who worked at Harvard University and the American Museum of Natural History, in a May 1997 article for Natural History.

Erosion and uplift may seem like obvious ideas today, 487 years after da Vinci’s death, but in his time, such ideas required independent thinking. Most people followed a literal interpretation of the Bible and thought that God created Earth about 6,000 years ago and that Noah’s flood was responsible for carving Earth’s features. But da Vinci “didn’t believe in Noah’s flood,” Lewis says. “He went out, looked at the rocks, watched the rivers, observed what was happening, and then put two and two together.”

Da Vinci also countered the era’s commonly held ideas about fossils. Some people held that fossils were “sports of nature,” meaning that some other being had put them within the rocks to look like once-living objects, Lewis says. Others thought that fish eggs, upon becoming lodged in cracks in rocks, grew into fossils, or that the stars influenced fossil formation. Da Vinci, however, “was one of the very early people to realize that they were simply the remains of creatures that had once lived on Earth and became buried by mud when they died,” she says.

By observing layers of fossil seashells in the mountains, which he realized had started out as layered sediments in the sea, da Vinci began to understand the scope of geologic time. While he didn’t comprehend scales of millions or billions of years, Lewis says, he concluded that the shaping of Earth took much longer than the 6,000 years as called for by the Bible.

Most of da Vinci’s notes on water, erosion, rock layers and fossils appear in one of his famous notebooks now called the Codex Leicester (which is currently owned by Microsoft’s Bill Gates and is on a traveling exhibit around the world). But the “great tragedy,” Lewis says, is that da Vinci never published any of his work. Had da Vinci published during his lifetime, “he individually might have progressed science by hundreds of years,” she says.

Without da Vinci’s notebooks, generations of scientists after him independently arrived at similar conclusions about Earth processes — it just took some extra time. Ajoy Baksi, a geophysicist at Louisiana State University in Baton Rouge who has read part of the translated Codex, says he was surprised by da Vinci’s sudden statement in the text that the “sun does not move.” Baksi first thought that da Vinci was referring to ideas from Copernicus, the astronomer widely credited for the idea of a sun-centered solar system. “Then I realized that could not be so,” Baksi says. Copernicus’ book was published on his death bed in 1543, whereas da Vinci’s “observation” was made at least 30 years earlier, he says.

Despite his genius, some details eluded da Vinci, such as the exact process that changes life forms into fossils, Lewis says. He was also led astray by the idea that processes on Earth (the macrocosm) were analogous to processes in humans (the microcosm). He thought, for example, that water circulated on Earth in a similar fashion as blood circulates in humans.

Nonetheless, da Vinci’s observational powers were “amazing” Lewis says, which thanks to the Codex, we now know go far beyond art and engineering. As Gould wrote in his 1997 article, da Vinci was a “Victorian geologist somehow trapped in the early sixteenth century.”

Kathryn Hansen

Back to top

Thomas Jefferson: Founding father of American paleontology

The East Room of the White House has been the backdrop for many notable and dignified events over the course of its history: from bill-signing ceremonies and receptions honoring Nobel Prize laureates, to elegant dinners and presidents lying in state. But for several months in 1808, the original East Room housed rather unusual guests: the fossilized remains of several ancient animal species, including the American mastodon. The president in residence at the time was Thomas Jefferson.

In addition to being the third U.S. president, Thomas Jefferson, shown here in 1805, was also one of America’s earliest paleontologists. Image is from James L. Dick/Rembrandt Peale, courtesy of Monticello/Thomas Jefferson Foundation, Inc.

Jefferson, author of the Declaration of Independence and the third U.S. president, was also a learned man who pursued myriad interests outside the realm of politics. He was an architect, farmer, inventor, musician, scholar — and, perhaps most surprisingly, one of America’s earliest paleontologists.

Jefferson, in fact, was “probably the single most important person at the turn of the [19th ] century with respect to paleontology,” says Dennis Murphy, who developed the Thomas Jefferson Fossil Collection, an online exhibit of the Academy of Natural Sciences (ANS), in Philadelphia, Pa. Jefferson was a fossil enthusiast who contributed to the field as a collector, promoter and benefactor, he says.

An interest in fossils came naturally to Jefferson, who, as a product of the Enlightenment, was “very invested in learning how the world worked” and “avid in studying the natural world,” Murphy says. But Jefferson’s entry into the young science of paleontology was perhaps spurred by pride in the new nation as much as by a quest for knowledge.

In the mid-1700s, French naturalist Georges-Louis Leclerc, Comte de Buffon published his Theory of American Degeneracy, arguing that the animals of the New World — and even transplanted Europeans — were smaller and less virile than those of the Old World. He attributed their inferiority to an unfavorable climate in the New World.

Jefferson took offense to Buffon’s claim. In 1785, Jefferson rebutted Buffon’s ideas in his Notes on the State of Virginia, in which he compared the sizes of American and European animals. The coup de grace of his rebuttal was the mastodon, regarded by Jefferson as a “giant beast” with “giant teeth” that was “clearly bigger than anything in Europe,” Murphy says.

Jefferson knew of the mastodon — which at the time was thought by some people to be an elephant or perhaps a mammoth — only from teeth and other bones discovered mostly in the Hudson and Ohio river valleys earlier in the 18th century. But because Jefferson believed in a “perfect creation” by a divine being, he found the idea of extinction difficult to swallow and believed the mastodon still existed, perhaps somewhere in the vast and unexplored American West, Murphy says. Nearly two decades later, in fact, President Jefferson would instruct Meriwether Lewis and William Clark to search for mastodons during their Western expedition (see Geotimes, September 2006).

This molar tooth from an adult mastodon, discovered in an expedition commissioned by Thomas Jefferson, once graced the White House and is now kept at the Academy of Natural Sciences. Roots extend downward from the tooth, which has cusps that are well-worn from use.Image is courtesy of The Academy of Natural Sciences.

In the meantime, however, Jefferson became the president of the American Philosophical Society in Philadelphia, and, in 1799, initiated an appeal for naturalists to find a complete skeleton of the mastodon. The appeal fueled an interest in paleontology among the scientific community that spilled over to the public in 1801, after an expedition party recovered two nearly complete skeletons (each was missing the top of the skull) that eventually were displayed in several cities, including Philadelphia and New York.

Along with the mastodon, Jefferson took a keen interest in the fossils of an animal he named Megalonyx, or “great claw,” after the large, menacing claws of its hand. Jefferson initially believed that the fossils, sent to him by a friend sometime in the late 1700s, were of a lion-like animal much larger than any European lion. Later, however, he heard about similar fossils found in Paraguay that belonged to Megatherium, a relative of the sloth, and reconsidered his interpretation.

In 1797, Jefferson presented a talk about Megalonyx to the American Philosophical Society, giving his own interpretation of the fossils as those of a large cat. But as an “intellectually honest” thinker, Jefferson also acknowledged, albeit skeptically, the possibility that the fossils were instead of a sloth-like creature, Murphy says. Indeed, they were, as Jefferson would later concede. He also asserted that, like the mastodon, Megalonyx was probably still alive — although he would later change his mind on this, too, and accept the idea of extinction. In 1799, Jefferson became the author of what is arguably America’s first scientific paper about paleontology, when his talk was published in the Transactions of the American Philosophical Society.

In 1807, Jefferson — who still wanted to find more mastodon remains, especially an intact skull — personally financed an expedition by Clark at Big Bone Lick, a fossil-rich site in Kentucky. Clark’s party eventually recovered several hundred specimens from the mastodon and other species, including ancient bison, moose and horses.

In 1808, Clark shipped these fossils to the White House, where Jefferson spread them out in the East Room. With the help of a prominent Philadelphia anatomist, Jefferson divided the fossils into three groups, sending one group to the Museum of Natural History in Paris and another to his home in Monticello. The third group went to the American Philosophical Society, which later transferred it to ANS.

Today, ANS still houses some of the fossils that once graced the White House, as well as others Jefferson collected, such as Megalonyx. Although the fossils are not available for public viewing, armchair paleontologists can glimpse the virtual Thomas Jefferson Fossil Collection and a detailed account of its history anytime at its Web site:

Jennifer Yauck

"September 23, 1806: Lewis and Clark return home," Geotimes, September 2006 Print Exclusive
The Academy of Natural Science, the Thomas Jefferson Fossil Collection

Back to top

Edward Jenner: From speckled monster to sea monster

For most people, discovering the fossilized remains of a large ancient animal would be a noteworthy event, if not the accomplishment of a lifetime. But when a person’s life accomplishments include pioneering a means to prevent one of the world’s most feared diseases, even spectacular paleontological achievements can get lost in the shuffle.

Edward Jenner, best known for his work with smallpox, dabbled in geology and paleontology throughout his life. The Berkeley countryside, visible in the background of this painting, inspired his interest in these pursuits. Image is from John Raphael Smith/William Pearce, courtesy of the Edward Jenner Museum.

Edward Jenner, an English physician, is renowned for his work with the “speckled monster,” smallpox, which was a leading cause of death in the 18th century. Jenner suspected that cowpox, a mild viral infection of cows that can be transferred to humans, protected people against smallpox. In 1796, he famously tested his hypothesis by inoculating an eight-year-old boy with cowpox, and then later with smallpox, to which the boy indeed resisted infection. Jenner’s experiment — the first-ever documented vaccination (from vacca, the Latin for cow) — became the basis for a procedure that would eventually eradicate smallpox worldwide and ensure Jenner a place in medical history.

A lesser known fact about Jenner, however, is that long before he began his legendary work in medicine, he was drawn to natural history. “He was very interested in it as a child because he lived in the countryside,” says Sarah Parker, director of the Jenner Museum in Jenner’s hometown of Berkeley, England. Growing up in the rural town in the mid-1700s, the young Jenner frequently explored the local geology and visited the banks of the nearby River Severn to search for fossils.

Jenner’s interests in geology and fossils carried over into his adult life, Parker says. He kept abreast of the latest geologic theories of his time, reading the works of people such as William Smith, the geologist who developed the concept of stratigraphy and designed the famous “map that changed the world,” the first geological map (see Geotimes, October 2003). In 1809, Jenner was elected an honorary member of the Geological Society of London.

According to Parker, Jenner was “an astute observer” who noted that the “ooliths” that made up some of the local limestone beds were formed by calcium crystals layered around sand grains or shell fragments. He also protested the quarrying of an outcrop of columnar rock near Berkeley that he recognized as a rare geological wonder, saying it was even more impressive than the Giant’s Causeway, the famous outcrop of polygonal basalt columns in Northern Ireland, Parker says.

From about 1812 to 1814, Jenner belonged to the Barrow Hill Club, a group of friends that met regularly to collect fossils. Some of Jenner’s finds, including a fern imprinted on coal, a clam shell and a shoulder bone from a whale, are on exhibit at the Jenner Museum.

But Jenner’s most significant paleontological find came in 1819, when he discovered the remains of a “sea monster” — a plesiosaur — at the base of Stinchcombe Hill near Berkeley. The find was “one of the earliest in Britain,” Parker says, and occurred several years before the plesiosaur was officially recognized as a species distinct from the better-known ichthyosaur. According to Roger Clark, curator of geology at the Bristol City Museum and Art Gallery in England, Jenner gave his plesiosaur specimen to the Bristol Institution, the forerunner of the museum, in 1823, making it one of the earliest objects in the institution’s collection.

Physician Edward Jenner discovered the fossilized remains of a plesiosaur, perhaps similar to this sketch of Plesiosaurus published by Richard Owen in 1860. Image is courtesy of Mike Everhart.

But like the “speckled monster,” Jenner’s “sea monster” has disappeared. Unfortunately, Clark says, Jenner’s plesiosaur is currently unaccounted for among the museum’s holdings and likely “went the way of others of our prized possessions when the museum building was completely burned out when Bristol was bombed” during World War II. Jenner’s scientific legacy, however, remains.

Jennifer Yauck

"Searching for The Map," Geotimes, October 2003

Back to top

Herbert and Lou Hoover: A dynamic and geologic pair

Herbert Hoover is best known as the 31st U.S. president — the unlucky man on whose watch the stock market crashed in 1929, kicking off the Great Depression of the 1930s. Only a single-term president, Hoover’s dry, deliberate manner quickly alienated a public desperate for the warmth and charisma offered by Franklin Delano Roosevelt, who succeeded him in 1933.

Herbert and Lou Hoover, both trained geologists, cross the White House lawn on March 4, 1929, the day of Hoover’s presidential inauguration. Image is courtesy of Herbert Hoover Presidential Library.

Hoover’s methodological approach to governing was not the result of a cold, callous nature, however, but was instead closely connected with his background as a geologist and mining engineer, says Timothy Walch, director of the Herbert Hoover Presidential Library and Museum, which is part of the National Archives and is located in Hoover’s birthplace of West Branch, Iowa. A pragmatic, energetic and dedicated public servant — with no talent for public speaking — Hoover believed that the scientific method, although sometimes slow to achieve results, was the surest way to get things done properly in office, just as in the field.

“He always felt engineers and scientists were called to a higher order,” Walch says. Raised on a farm in a moralistic Quaker family, Hoover prized straightforward rationalism and thought that reasoned, dispassionate scholars would be “better leaders,” who would apply scientific principles and methods to the running of a government and would not succumb to the same kinds of temptations as other politicians, Walch says.

Attracted to math, Hoover wanted to become an engineer and was drawn to the new, tuition-free Stanford University in Palo Alto, Calif., which offered a mining engineering program. He entered Stanford in 1891, where he met his future wife, Lou Henry. Lou, also from Iowa, shared a love of the outdoors with Hoover, and had early aspirations to become a geologist after studying rock formations on long hikes with her father. She later became the first woman to receive a geology degree from Stanford.

Hoover, meanwhile, studied geology under John Caspar Branner, the former state geologist of Arkansas. Working summers at the Arkansas Geological Survey and California Geological Survey, Hoover embraced geological fieldwork, and hoped for a permanent position with the U.S. Geological Survey once he graduated. The survey, however, was burdened with financial difficulties, and without the prospect of employment there, Hoover turned back to mining.

Starting as a miner on the night shift in the gold mines of Nevada County, he eventually got a job as a typist for a consulting engineer, where he was able to demonstrate his skills and was promoted to an assistant position. From there, he worked his way up through the mining business.

Hoover traveled with Lou through 57 countries during his mining career, first as an engineer and then as a mine manager, displaying an efficient, accurate talent for sizing up a mine’s potential. “He frequently found rich veins of minerals where others said the property was played out,” Walch says.

Lou stayed at his side and displayed her own talent for languages. During their travels, she and Hoover translated a 16th-century Latin text on mining by Agricola called De Re Metallica. First published in English in 1912, it is the oldest known work on mining in the Western world that is still in print.

In the end, Hoover’s mining career made him a millionaire. Although intensely private about his income, Walch says, he lived off of his earnings as an engineer throughout his life and never accepted any salary as president, instead donating the money to charity.

By the onset of World War I in 1914, Hoover had turned his attention from engineering to public service. He became head of the American Food Administration during World War I, organizing shipments of food to millions of people in Central Europe. He then became secretary of the Department of Commerce in 1921 under President Warren G. Harding, and maintained that position under Harding’s successor Calvin Coolidge. As secretary, he developed projects for land irrigation, electrical power and flood control.

In 1927, he reached a high point in public popularity when he helped mobilize state and local authorities, militia, the Coast Guard and the American Red Cross to deal with the aftermath of the Great Mississippi Flood and control disease outbreak. In 1928, he became the Republican candidate for president, campaigning on a platform of efficiency and prosperity.

After the stock market crash and the severe drought that followed in the summer of 1930, however, Hoover was unable to restore confidence in economic recovery. He initiated a number of government-funded programs and raised taxes in an effort to combat the ensuing Great Depression, which won him no one’s favor.

The downfall of Hoover’s presidency, Walch says, was at least partially due to bad timing. Hoover “didn’t have the temperament we needed at that moment,” Walch says, while Roosevelt was “intuitively inspirational.” A fundamental difference between the archetypal politician and scientist personalities may also have worked against Hoover, he says.

“Politicians often have to promise more than they can deliver,” Walch says, “but Hoover had a scientific, dispassionate mind. Give us the facts — that was his style.”

Carolyn Gramling

Back to top


Untitled Document

Geotimes Home | AGI Home | Information Services | Geoscience Education | Public Policy | Programs | Publications | Careers

© 2018 American Geological Institute. All rights reserved. Any copying, redistribution or retransmission of any of the contents of this service without the express written consent of the American Geological Institute is expressly prohibited. For all electronic copyright requests, visit: