Lewis and Clark Weren't the Only Explorers to Map the American Frontier

Victory by the United States in the Revolutionary War didn't mark the end of its problems with European conquest of North America. As Julie M. Fenster describes in Jefferson's America, her remarkable history of the exploration of the American frontier, without proper mapping and settlement, the Louisiana Purchase was little more than a few words on paper, the territory ripe to be plucked away, part and parcel, by Spain, France, and England.

"The French," writes Fenster, "sold Louisiana and intentionally left the detail of drawing boundaries to the new owners." She later writes that the Spanish, who had a significant military and administrative presence in the western frontier, "had come to the sensible conclusion that without money or soldiers or people in abundance, a territory can't be controlled. It can only be held, and rather gently ... Exploration could assert control, because accurate information was another basis of power."

The Louisiana Purchase was France's idea. With the French and British on the cusp of war, Napoleon didn't dare attempt to hold a North American front in addition to the European theatre. He knew that the British would invade from Canada at the first opportunity. Moreover, France's grip on its North American holdings was tenuous at best, the U.S. Congress making things worse with its increasing disposition in favor of an armed seizure of New Orleans. The whole continent was just more trouble than it was worth, and so the French government offered to sell its territory for a song.

Jefferson jumped at the opportunity and, as he later wrote, "by a reasonable and peaceable process, we have obtained in 4. months what would have cost us 7. years of war, 100,000 human lives, 100 millions of additional debt."

For Jefferson, it was about more than territory and political intrigue. While holding the offices of the vice presidency and later the presidency, he also ran the American Philosophical Society, one of the first science institutions in the United States. The frontier presented a bonanza of unknown flora, fauna, ecosystems, and geology, and it was Jefferson's personal obsession to have the frontier thoroughly mapped and studied.

Such exploration would be no small task either physically or intellectually. In his own words, he sought in his ideal explorer "a person who to courage, prudence, habits & health adapted to the woods, & some familiarity with the Indian character, joins a perfect knowledge of botany, natural history, mineralogy & astronomy." Though he doubted such men existed in America, a blizzard of correspondence issued by his own hand would turn up a few explorers up to the task. These explorers were sometimes called "Jefferson's Men," and they managed the seemingly impossible: the exploration, mapping, and surveying of the west. Here are seven explorers of the American frontier, and how they did it.


Public Domain, Wikimedia Commons

Captain Meriwether Lewis and Lieutenant William Clark were tasked by Jefferson to explore the Louisiana territory and map a route across the western half of North America. They were to satisfy Jefferson's hopes for information on flora and fauna, and to establish trade with the American Indians they encountered along the way. Moreover, they were to assert American sovereignty over the areas explored—in other words, to let everyone they encountered know that this land was our land. There and back, the expedition lasted just under two-and-a-half years. The journey started out in Wood River, Illinois, and ended at the mouth of the Columbia River in present-day Washington State.

The return trip, which lasted six months, saw the group split so as to more efficiently explore even more territory, which included Yellowstone and the Continental Divide. The expedition ended on September 23, 1806. This expedition is notable for the inclusion of Sacajawea, whose contributions involved some work as a guide, but far more significantly, as a multilingual ambassador to tribes encountered along the way.


William Dunbar / Public Domain, Wikimedia Commons

Fenster describes George Hunter as an "animated tourist," who "delighted in everything from the howl of wolves in the distance to the sight of another vessel on the river." He was "a good frontiersman and always a resilient one." He was also a chemist of some repute, which fit Jefferson's bill for someone able to truly study the land. William Dunbar, meanwhile, was a wealthy trader whose loyalties were ever in motion. Spanish, French, American—it was all the same to him. He just wanted to be out there. He had a love of, and talent for, science, and word of this reached the vice president of the United States and president of the American Philosophical Society. In Fenster's words, Jefferson "initiated correspondence, capturing Dunbar as though he were a bird formerly believed extinct."

While Lewis and Clark explored the northern part of the Louisiana Purchase, Dunbar and Hunter, soon brought together, were charged with the Ouachita River, an "alligator-infested, lumber-clogged river in the parched Southwest." The expedition brought them to the hot springs of Arkansas. Ultimately, the men completed a geologic and zoological study of the land along the river, as well as a chemical analysis of the hot springs.


In 1806, Thomas Freeman and Peter Custis embarked on an exploration of the Red River. Freeman was a highly accomplished surveyor who had completed the highly contentious survey of what would be the nation's capital on the Potomac, and later helped survey the 31st Parallel separating U.S. and Spanish territory in the Southeast. (A present-day map of the United States will reveal a straight line dividing part of Louisiana from Mississippi, and Florida from Alabama. That is the 31st Parallel. His work in D.C. and in establishing the borders of southern states has stood the test of time.) Custis brought to the expedition his expertise as a naturalist and a physician-in-training.

The men traveled from Natchez, Mississippi to present-day New Boston, in northeast Texas. Along the way, they encountered "almost impenetrable Swamps & Lakes for more than 100 miles," according to Custis. In Texas, they encountered Spanish soldiers who had been tipped off about their expedition, and were made to turn back. Still, the scientific observations gathered from the 600-mile stretch of frontier proved invaluable to Jefferson, who now knew the land to be worthy of settlement. It also established warm relations with native tribes along the way, and the fallout from the Spanish confrontation would force Spain to allow American expeditions along its Red River holdings.


Public Domain, Wikimedia Commons

Zebulon Pike first joined the Army at the age of 15, and 12 years later would be placed in charge of an expedition that would cross the Great Plains and the Rocky Mountains. Pike was, according to Fenster, "born supremely, even mythologically, confident in his sense of mission." The expedition wasn't an easy one. After crossing present-day Kansas, they arrived at the Rockies in time for winter and with but a single layer of cotton clothing.

"They had no coats," writes Fenster, "Or even socks." When trying to make their way and accurately ascertain where they were, Pike led a group of men to a "blue-tinted mountain" where they might look down and survey the terrain. What seemed a one-day hike turned into four, and even then the mountain "now appeared at the distance of 15 or 16 miles from us, and as high again as what we had ascended." Fenster describes the mountain as having been "apparently on wheels," seeming always to be those 15 miles away. Pike eventually turned around, the mountain being "the only thing on earth that ever made him give up."

The ensuing winter was unkind to the explorers, bringing frostbite, illness, near-starvation, and subzero temperatures. Still, his men believed in Pike and his indomitable spirit, and they survived; they eventually reached the Rio Grande in Spanish territory, where they were rescued (and captured) by the Spanish. Pike and his men were brought to Mexico, and later escorted to the Louisiana border at Natchitoches. The blue-tinted mountain was, of course, what is now called Pike's Peak.

Interactive Map Shows Where Your House Would Have Been 750 Million Years Ago

Your neighborhood traveled a long way over several hundred million years to reach the spot it occupies today. To trace that journey over the ages, check out Ancient Earth, an interactive digital map spotted by Co.Design.

Ancient Earth, a collaboration between engineer and Google alum Ian Webster and Paleomap Project creator C.R. Scotese, contains geographical information for the past 750 million years. Start at the beginning and you'll see unrecognizable blobs of land. As you progress through the ages, the land mass Pangaea gradually breaks apart to form the world map we're all familiar with.

To make the transition even more personal, you can enter your street address to see where it would have been located in each period. Five hundred million years ago, for example, New York City was a small island in the southern hemisphere isolated from any major land mass. Around the same time, London was still a part of Pangaea, and it was practically on top of the South Pole. You can use the arrows on your keyboard to flip through the eras or jump from event to event, like the first appearance of multicellular life or the dinosaur extinction.

As you can see from the visualization, Pangaea didn't break into the seven continents seamlessly. Many of the long-gone continents that formed in the process even have names.

[h/t Co.Design]

Illustration by Mental Floss / Images: iStock
11 Facts About the Appendix
Illustration by Mental Floss / Images: iStock
Illustration by Mental Floss / Images: iStock

Despite some 500 years of study, the appendix might be one of the least understood structures in the human body. Here's what we know about this mysterious organ.


The human appendix is small, tube-shaped, and squishy, giving ancient Egyptians, who encountered it when preparing bodies for funerary rites, the impression of a worm. Even today, some medical texts refer to the organ as vermiform—Latin for "worm-like."


The earliest description of a human appendix was written by the Renaissance physician-anatomist Jacopo Berengario da Carpi in 1521. But before that, Leonardo da Vinci is believed to drawn the first depiction of the organ in his anatomical drawings in 1492. Leonardo claimed to have dissected 30 human corpses in his effort to understand the way the body worked from mechanical and physiological perspectives.


The appendix is a small pouch connected to the cecum—the beginning of the large intestine in the lower right-hand corner of your abdomen. The cecum’s job is to receive undigested food from the small intestine, absorb fluids and salts that remain after food is digested, and mix them with mucus for easier elimination; according to Mohamad Abouzeid, M.D., assistant professor and attending surgeon at NYU Langone Medical Center, the cecum and appendix have similar tissue structures.


The appendix has an ill-deserved reputation as a vestigial organ—meaning that it allegedly evolved without a detectable function—and we can blame Charles Darwin for that. In the mid-19th century, the appendix had been identified only in humans and great apes. Darwin thought that our earlier ancestors ate mostly plants, and thus needed a large cecum in which to break down the tough fibers. He hypothesized that over time, apes and humans evolved to eat a more varied and easier-to-digest diet, and the cecum shrank accordingly. The appendix itself, Darwin believed, emerged from the folds of the wizened cecum without its own special purpose.


The proximity and tissue similarities between the cecum and appendix suggest that the latter plays a part in the digestive process. But there’s one noticeable difference in the appendix that you can see only under a microscope. “[The appendix] has a high concentration of the immune cells within its walls,” Abouzeid tells Mental Floss.

Recent research into the appendix's connection to the immune system has suggested a few theories. In a 2015 study in Nature Immunology, Australian researchers discovered that a type of immune cells called innate lymphoid cells (ILCs) proliferate in the appendix and seem to encourage the repopulation of symbiotic bacteria in the gut. This action may help the gut recover from infections, which tend to wipe out fluids, nutrients, and good bacteria.

For a 2013 study examining the evolutionary rationale for the appendix in mammal species, researchers at Midwestern University and Duke University Medical Center concluded that the organ evolved at least 32 times among different lineages, but not in response to dietary or environmental factors.

The same researchers analyzed 533 mammal species for a 2017 study and found that those with appendices had more lymphatic (immune) tissue in the cecum. That suggests that the nearby appendix could serve as "a secondary immune organ," the researchers said in a statement. "Lymphatic tissue can also stimulate growth of some types of beneficial gut bacteria, providing further evidence that the appendix may serve as a 'safe house' for helpful gut bacteria." This good bacteria may help to replenish healthy flora in the gut after infection or illness.


For such a tiny organ, the appendix gets infected easily. According to Abouzeid, appendicitis occurs when the appendix gets plugged by hardened feces (called a fecalith or appendicolith), too much mucus, or the buildup of immune cells after a viral or bacterial infection. In the United States, the lifetime risk of getting appendicitis is one in 15, and incidence in newly developed countries is rising. It's most common in young adults, and most dangerous in the elderly.

When infected, the appendix swells up as pus fills its interior cavity. It can grow several times larger than its average 3-inch size: One inflamed appendix removed from a British man in 2004 measured just over 8 inches, while another specimen, reported in 2007 in the Journal of Clinical Pathology, measured 8.6 inches. People with appendicitis might feel generalized pain around the bellybutton that localizes on the right side of the abdomen, and experience nausea or vomiting, fever, or body aches. Some people also get diarrhea.


Treatment for appendicitis can go two ways: appendectomy, a.k.a. surgical removal of the appendix, or a first line of antibiotics to treat the underlying infection. Appendectomies are more than 99 percent effective against recurring infection, since the organ itself is removed. (There have been cases of "stump appendicitis," where an incompletely removed appendix becomes infected, which often require further surgery.)

Studies show that antibiotics produce about a 72 percent initial success rate. “However, if you follow these patients out for about a year, they often get recurrent appendicitis,” Abouzeid says. One 2017 study in the World Journal of Surgery followed 710 appendicitis patients for a year after antibiotic treatment and found a 26.5 percent recurrence rate for subsequent infections.


You might imagine a ruptured appendix, known formally as a perforation, being akin to the "chestbuster" scene in Alien. Abouzeid says it's not quite that dramatic, though it can be dangerous. When the appendix gets clogged, pressure builds inside the cavity of the appendix, called the lumen. That chokes off blood supply to certain tissues. “The tissue dies off and falls apart, and you get perforation,” Abouzeid says. But rather than exploding, the organ leaks fluids that can infect other tissues.

A burst appendix is a medical emergency. Sometimes the body can contain the infection in an abscess, Abouzeid says, which may be identified through CT scans or X-rays and treated with IV antibiotics. But if the infection is left untreated, it can spread to other parts of the abdomen, a serious condition called peritonitis. At that point, the infection can become life-threatening.


In 1894, Charles McBurney, a surgeon at New York's Roosevelt Hospital, popularized an open-cavity, muscle-splitting technique [PDF] to remove an infected appendix, which is now called an open appendectomy. Surgeons continued to use McBurney's method until the advent of laparoscopic surgery, a less invasive method in which the doctor makes small cuts in the patient's abdomen and threads a thin tube with a camera and surgical tools into the incisions. The appendix is removed through one of those incisions, which are usually less than an inch in length.

The first laparoscopic appendectomies were performed by German physician Kurt Semm in the early 1980s. Since then, laparoscopic appendectomies have become the standard treatment for uncomplicated appendicitis. For more serious infections, open appendectomies are still performed.


When the future King Edward VII of Great Britain came down with appendicitis (or "perityphlitis," as it was called back then) in June 1902, mortality rates for the disease were as high as 26 percent. It was about two weeks before his scheduled coronation on June 26, 1902, and Edward resisted having an appendectomy, which was then a relatively new procedure. But surgeon and appendicitis expert Frederick Treves made clear that Edward would probably die without it. Treves drained Edward's infected abscess, without removing the organ, at Buckingham Palace; Edward recovered and was crowned on August 9, 1902.


On August 26, 2006, during an autopsy at a Zagreb, Croatia hospital, surgeons obtained a 10.24-inch appendix from 72-year-old Safranco August. The deceased currently holds the Guinness World Record for "largest appendix removed."


More from mental floss studios