Mapping the Laramie Plains, Part I In pursuit of the third dimension
In the spring of 1893, Albany County Surveyor W.O. Owen received a set of maps from the US Geological Survey for review. Owen had known what to expect, but the others who viewed them were surprised. "The maps are of a very interesting character ...", wrote a reporter for the Laramie Boomerang, "almost every hill and cañon can be determined at a glance!"
Indeed, the new map was astonishing—mountains and depressions around Laramie had been clearly mapped using squiggly lines! But this achievement was long in coming. For millennia, mappers had struggled to show topographical relief, to capture the third dimension on a two-dimensional sheet of paper.
Line + cones = valley
In 1160 B.C. Scribe-of-the-Tomb Amennakhte made a map for Pharaoh Ramesses IV, who was planning a trip to quarry sandstone suitable for statues. On papyrus, he drew a broad winding line with bumpy cones lying flat on either side. With a bit of imagination, we see this is a valley lined with hills.
Amennakhte's hills look terribly crude to our eyes. Yet they aren't all that different from those appearing on maps for the next two millennia. As late as the 16th century, during early exploration of North America, mountains were shown as oversized cones, though sometimes shaded to suggest depth. Often their locations were based on distant views from sea, or rumors.
Lewis & Clark map new territory
The next centuries brought significant improvements in surveying and mapping, fortunately. In the early 1800s, the young United States was in desperate need of good maps. The Louisiana Purchase had doubled the country's size. Little was known about the new territory—not even its size, nor how to traverse it.
In May 1804, the Corps of Discovery Expedition, led by Meriwether Lewis and William Clark, headed up the Missouri River in search of a route to the Pacific Ocean. In preparation for the trip, Lewis was trained in celestial navigation. President Thomas Jefferson personally provided instructions for mapping:
"... you will take observations of latitude & longitude, at all remarkable points on the river [e.g., rapids, river mouths, islands]. The interesting points of the portage between the heads of the Missouri, & of the water offering the best communication with the Pacific ocean, should also be fixed by observation ..." [Jefferson assumed they could reach a west-flowing river by carrying their boats overland.] "Your observations are to be taken with great pains & accuracy, to be entered distinctly & intelligibly for others as well as yourself, to comprehend all the elements necessary, with the aid of the usual tables, to fix the latitude and longitude of the places ..." They faithfully executed Jefferson's instructions, for three years, four months, ten days and 8000 miles.
Clark's map reveals a multitude of mountains
William Clark took on the job of mapmaker. In addition to the Expedition observations, he used information from explorers, trappers, natives, and earlier maps to include areas not covered by the expedition. His first map showed the Corps’ route in great detail and was necessarily huge—50+ large sheets. He then produced a single map 52 inches long and 31 inches wide, engraved and published in 1814: “A Map of Lewis and Clark's Track, Across the Western Portion of North America ...”
Among the discoveries visible on Clark's map is the structure of the Rocky Mountains. They are not a single long ridge as previously thought, but a complex system of mountain ranges and foothills. In fact, after reaching the headwaters of the Missouri, the Corps of Discovery had to travel for weeks on horseback and foot to reach west-flowing waters. A portage across the Rockies was out of the question.
Clark drew mountains using hachures—short parallel lines looking something like eyelashes. Length and curvature gave a sense of height and steepness. Hachures were denser and darker on east and south slopes of ranges, suggesting a third dimension.
In general, Clark's map was accurate by the standards of the day. But there is a glaring error in the southern part. The Laramie Plains and surrounding mountains are missing! Little was known about the territory that would become southern Wyoming, so future Colorado and Kansas were moved north to fill the gap. This is why the Kanzas [sic] River was shown flowing where Rawlins and Laramie are today.
Pathfinder puts Laramie Plains on the map
In July 1843, a small contingent of the US Army Corps of Topographical Engineers climbed out of the canyon of the Cache-à-la-Poudre River, where they had hoped to find a route over the Rocky Mountains. Instead, they crossed the broad divide to the north.
In command was a young ambitious lieutenant—John Charles Frémont, the Pathfinder. This was the second of five expeditions he would lead through the American West, each time making significant contributions to geographical knowledge. He also would be court-martialed, lose a presidential election, squander large sums of money in mining schemes, and die in poverty. But all that was far in the future on that lovely summer day when the Laramie Plains came into view.
"The weather was pleasant and cool, we were disturbed by neither musquitoes [sic] nor flies; and the country was certainly extremely beautiful," Frémont would write in his report. "The slopes and broad ravines were absolutely covered with fields of flowers of the most exquisitely beautiful colors. ... As we emerged on a small tributary of the Laramie river, coming in sight of its principal stream, the flora became perfectly magnificent; and we congratulated ourselves, as we rode along our pleasant road, that we had substituted this for the uninteresting country between Laramie hills and the Sweet Water valley."
Challenges: stones, sagebrush, longitude
That evening, they camped on the Main Fork of the Laramie River, where Frémont took astronomical readings to determine latitude and longitude (see map). While latitude seems to have been accurate, his calculation of longitude put them too far west, in the Medicine Bow Mountains near Lake Owen (according to Google Earth). But that's not surprising. Estimating longitude was difficult, requiring careful tracking of stars with a precision telescope and a chronometer [clock] that kept steady time, or at least lost time at a steady rate.
For three days the party traveled northwest along the Medicine Bow mountain [sic]. The going was easy at first, but near the mountain they were slowed by large round stones in the soil. Equally difficult were ridges "made extremely rough by the stiff tough bushes of artemisia tridentata, in this country commonly called sage" [as it is today].
On August 2, they camped on the Medicine Bow River near "an isolated mountain called the Medicine Butte [Elk Mountain], which appeared to be about 1,800 feet above the plain, from which it rises abruptly, and was still white nearly to its base with a great quantity of snow". Frémont made more astronomical observations, this time including "an immersion [eclipse] of the first satellite of Jupiter." Even so, the calculated longitude again put them too far west.
After passing south of Elk Mountain, the party dropped down to the North Platte River, followed it to the Sweetwater, and continued on to California and Oregon. They would return home in August 1844, after about 15 months and 10,000 miles of travel.
Dramatic report, spectacular map
Frémont wrote a colorful report about his adventures, with the help of his wife, Jesse, whose father—the powerful Senator Thomas Hart Benton—had secured funding for the expedition. Ten thousand copies were published the following year, to rave reviews. Included was the spectacular “Map Of An Exploring Expedition To The Rocky Mountains,” measuring 52 x 30 inches, and stretching from the Missouri River west to the Pacific Ocean and from Los Angeles north to Mount St. Helens.
However, much of the map was blank—to Frémont's credit. In a Notice to the Reader, he explained: "The map may have a meagre and skeleton appearance to the general eye, but is expected to be more valuable to science on that account, being wholly founded upon positive data and actual operations in the field." Indeed, this map is now considered a milestone, having set a new standard of cartographic accuracy for the American West.
The mapmaker was Charles Preuss, a trained surveyor and topographic artist from Prussia. He would accompany Frémont on three expeditions, making "continuous topographical sketches of the regions through which we passed, and which were never interrupted by any extremity of fatigue or privation" (Frémont's words). The large beautiful maps secured his reputation as a great cartographer.
Laramie Plains up close
Like William Clark, Preuss drew mountains using hachures, but in greater detail. In the excerpt included here, small narrow drainages are visible on mountains slopes, and low ridges and buttes dot the plains. Preuss varied hachures to show height and steepness. Lower ridges were drawn with shorter lines. Denser darker hachures indicated steeper slopes—for example Laramie Peak (top center of map) and, a short distance southeast, the canyon where the Laramie River crosses the Black Hills (Laramie Mountains).
However, if we continue our examination, it isn't long before we're confused. What is that low mountain range paralleling the Medicine Bows—Jelm and Sheep Mountains? Or the ridge east of the Main Fork? Most puzzling is the “Right Hand Fork,” shown joining the Main Fork of the Laramie River before it enters the canyon.
Errors at this scale aren't surprising. With the great expanse of unknown territory ahead, there was little time for finer details, and though Preuss' map was highly accurate in its time, it's a far cry from the "very interesting map” showing every hill and canyon, which would so excite a Boomerang reporter 50 years later. [Stay tuned. More on this next week in Part II.]
View maps online
For more about Amennakhte's map for Ramesses IV, check out "Turin Papyrus Map" on Wikipedia. The Lewis & Clark and Frémont maps are available at the wonderful David Rumsey Map Collection (online). Go to www.davidrumsey.com and search for "William Clark 1814" and for "Frémont 1845." These images are high resolution, so zoom in super close—and maybe solve the mystery of the Right Hand Fork!
By Hollis Marriott
Editor’s Note:Hollis Marriott is all but retired, after working for forty years as a field botanist in Wyoming and South Dakota. Now she has time to enjoy her other interests, including outdoor recreation, music, natural history, and the history of scientific exploration of the American West
Laramie Plains from expedition map by Frémont and Preuss. Stars are astronomical observatories where they measured latitude and longitude. Triangles mark points where latitude was measured using the sun's height at noon. Today's state line added. Courtesy David Rumsey Map Collection, public domain.
Southern part of Map of Lewis and Clark's Track; note hachured mountain ranges. The Arkansas and Kansas Rivers were mapped hundreds of miles northwest of their true location, putting them in the vicinity of today's Rawlins and Laramie (added). Courtesy David Rumsey Map Collection, public domain.
Excerpt from Amennakhte's map for pharaoh Ramesses IV (correct order of fragments is debated); housed at Museo Egizio in Italy. Photo of "Turin Papyrus" from Wikimedia Commons; public domain.