new item

new item


Who Mapped the Course of the Humboldt River on the 1848 Frémont-Preuss Map?


Page UnderConstruction

From the 1848 Fremont-Preuss Map of Oregon and California*
*Oregon, before 1848, refers to the jointly occupied by the United States and England north of latitude 42 degrees, and before the Treaty of Guadalupe Hidalgo, California included Mexican territory south of 42 degrees, and east to the Rocky mountains.

This was a watershed map, the basis of all other maps of the West that followed it for decades, and it was the first map to accurately show the course of the Humboldt River, that great artery that brought thousands of gold seekers and settlers to California.
I had never considered the question "Who mapped it?" until Scott Stine put it to me.

The Frémont-Preuss maps--the 1843 map of the 1842 first expedition route, the 1845 map of the 1843-44 second expedition route, the seven section large scale roadmap of the Oregon Trail, and the 1848 map of Oregon and California--were a collaboration based on the coordinates determined by Frémont's astronomical observations, and his cartographer Charles Preuss' map sketches, topographical notes, and compass bearings. The maps were drawn by Charles Preuss and published at very great expense by Congress. The engraving and printing costs for the 30" x 52" 1:1,950,000 1845 map amounted to some $10,000.

On that second expedition in 1843-44, Frémont was looking for the river (he then called it Mary's River) when coming south from the Columbia River along the western edge of what he would later describe and name the Great Basin, but he was west of its sink. And because he was never on, didn't see, the Humboldt, it does not appear on the 1845 Frémont-Preuss map--a white-paper map, that showed only where they traveled and what they saw.
The 1845 Frémont-Preuss map.

The river Frémont named Humboldt in 1845 is very perfectly delineated on the 1848 Frémont-Preuss map. It is shown as a detail at right, compared with a modern map of the river.
Problem! neither Frémont nor Preuss were on the Humboldt River during either the second or third expedition. And no one else had accurately mapped it before them.
The 1848 Frémont-Preuss map.

Frémont of the start of the 3rd expedition:

"Mr. Preuss was not with me this time, but was now in assured employment and preferred in his comfortable home to rest from the hardships of the last journey. In his place Mr. Edward M. Kern, of Philadelphia, went with me as topographer. He was besides an accomplished artist; his skill in sketching from nature and in accurately drawing and coloring birds and plants made him a valuable accession to the expedition."

After passing around the southern end of Great Salt Lake on November 8, Frémont made the first ever crossing of the salt desert to Pilot Peak.

"I now divided the party, giving to Mr. Kern the charge of the main body with instructions to follow down and survey the Humboldt River and its valley to their termination in what was called "the Sink." This is a broad valley of fertile land; probably once the bed of the lake when over all this region, at a time not very remote, the waters were higher. When I passed there two years later it was covered with grass and several varieties of clover. Thence to continue on along the eastern foot of the Sierra to a lake to which I have given the name of Walker, who was to be his guide on this survey."

Frémont gave it the name Humboldt River on the 1848 map. Previoussly it has been called Paul's River, Unknown River, Swampy River, and Mary's River (a fork still is) by Peter Ogden, Barren River by Joseph Walker, and Ogden's River by Bonneville,.

Kern wrote of the start of the Talbot-Walker division of the exploring party:

"November 5, 1845--Whitten's Spring. To-day we parted company, the captain passing to the southward with a small party, to examine that portion of the Great Basin supposed to be a desert, lying between the Sierra Nevada and the Rocky Mountains. The main body of the camp, under the guidance of Mr. Joseph Walker, are to move toward the head of Mary's or Ogden's River, and down that stream to its sink or lake. From thence to Walker's Lake, where we are again to meet. I am to accompany the latter party in charge of the topography, &c."

Edward Meyer Kern, usually called Ned, was born in Philadelphia in 1822 or 23. Trained as an artist, he was engaged as artist and topographer on Frémont's 3rd expedition, replacing Charles Preuss of the first and second expeditions. Kern's drawings documented the expedition, but because it was terminated by the Mexican War, no report was published. They were later made into paintings, and then plates not published until in Frémont's Memoirs of My Life in 1887.

Finding Edward Kern's 1846 vantage for his beautiful third expedition drawing of the Sutter Buttes.

Ned Kern made no notes in his diary of any activities relating to mapping. It is assumed that he, like Charles Preuss had on the two previous expeditions, was throughout each day's travel taking compass bearings of visible landmarks, keeping a record of miles traveled, and noting and sketching topographical features. But there is no indication anywhere that he had any navigational instruments, any training in the use of instruments, or the mathematical knowledge to reduce celestial observations. Charles Preuss also lacked these skills.

Frémont on his hiring of Charles Preuss for his first expedition:
"There were astronomical observations remaining unreduced. That work, I told him, I could get for him. This he said he was not able to do. His profession was topography--in this he excelled, but that was all. The only thing I could devise was to get for him this astronomical work and do it myself, which I could by working in the evenings. It troubled him greatly that I should have to do this for him, but it was the only way I could come in aid ; and so it was done."

Did Frémont also map the river himself in the summer of 1847, returning east following Brigadier General Steven Watts Kearny? Frémont wrote of Kearny:

"Taking away from me the command of my topographical party; taking away the scientific instruments which I had so long, used; leaving behind my geological and botanical specimens of near two years' collection; leaving behind the artist of the expedition, (Mr. Kern,) with his sketches and drawings; leaving behind my assistant, (Mr. King;) he and Mr. Kern both standing in a relation to be material witnesses to me in any inquiry into my conduct; denying me the privilege of returning to the United States by any new route which would enable me to correct previous explorations, or add to geographical and scientific knowledge; making me follow on his trail in the rear of his Mormon escort."

His remark that he was not able to "add to geographical and scientific knowledge" on this trip suggests that he did not map the course of the Humboldt. But even if he had mapped the river by compass, sketch maps, and estimated daily mileage, as Kern, or Preuss, would have done, who mapped the expedition course south from Walker Lake, along the base of the Sierra Nevada and Owens River and Lake, and into the San Joaquin Valley via Walker's Pass and the Kern River?

Frémont was never on that route, but his topographer Ned Kern was.

It seems most probable that the Humboldt River, as it appears on the 1848 Frémont-Preuss Map of Oregon and California was mapped by Edward M. Kern,.
Because it is certain that the route south of Walker Lake was Kern's mapping.

Edward Meyer Kern should be recognized for his important contributions not just as an artist and explorer, but as a mapper.

Frémont did honor Kern in naming the Kern River, upon which Kern traveled and mapped, as he had named the Carson River and Lake, Walker River and Lake, the Owens River and Lake, after other third expedition members Christopher Kit Carson, Joseph Rutherford Walker, and Dick Owens.

But in regard to the first mapping of the Humboldt River, as it says on the reverse of one of Frémont's own presidential campaign medals, Honor to Whom Honor is Due. Note the Capitol still sports the low 1818 Bullfinch dome.

goFrémont's describing and mapping of the Great Basin--"The Great Interior Basin...with no outlet to the sea."
goLongitude and the Buenaventura River--was Frémont really looking for the river depicted on so many maps?
go Frémont routinely made telescopic observations of the Galilean moons of Jupiter for longitude. Here is a naked-eye observation of Jupiter, apparently never recorded in the history of astronomy.
go Never determined or put to map before, the route of Frémont's 3rd expedition as it crossed the Sierra into California in December 1845.
goAbout John Charles Frémont
goHow did Frémont become a surveyor and mapmaker? How good was he?
goWatching the heavens change, How Polaris has moved 2 degrees closer to the celestial pole during recorded California history, and why Frémont got up at 3:00 a.m. and stand in the snow to sight polaris--hadn't it there all night long?


  • Blodget, Lorin, Climatology of the United States and the Temperate Latitudes of the North American Continent, J. B. Lippincott and Co., Philadelphia: 1857.
  • Bowditch, Nathaniel, Ll. D., The New American Practical Navigator, E. and G. W. Blunt, New York, 23rd Edition, 1853.
  • Cline, Gloria Griffin, Exploring the Great Basin, University of Oklahoma Press, Norman, 1963 (and University of Nevada Press reprint 1988).
  • Fletcher, F. N., Early Nevada--the Period of Exploration, 1776-1848, Reno, 1929.
  • Francaviglia, Richard. V., Mapping and Imagination in the Great Basin: a Cartographic History, University of Nevada Press, Reno, 2005.
  • Frémont, Jesse Benton, The Origin of the Frémont Explorations, The Century Magazine, March, 1891.
  • Frémont, Jesse Benton, The Origin of the Frémont Explorations, The Century Magazine, March, 1891.
  • Frémont, John Charles, Geographical Memoir Upon Upper California, Senate. 30th Congress, Misc. No. 148, Wendell and Van Benthuysen, Washington, 1848. Contains the 1848 Frémont/Preuss map.
  • Frémont, John Charles, Letter of John C. Fremont to the Editors of the National Intelligencer, communicating general results of a recent winter expedition across the Rocky Mountains, for the survey of a route for a railroad to the Pacific, Senate, 33d Congress, 1st Session, Mis. Doc No.67, Washington, June 13, 1854.
  • Frémont, John Charles, Memoirs of My Life, Belford, Clark & Company, Chicago, 1887.
    Now (Nov. 2001) available in Paper Back from Cooper Square Press, New York.
  • Goetzmann,William H., Army Exploration in the Americn West 1803-1863, Yale University Press, New Haven, 1959.
  • Hine, Robert V., In the Shadow of Frémont: Edward Kern and the Art of Exploration. 1845-1860, University of Oklahoma Press, Norman, 1982.
  • Jackson, Donald, and Mary Lee Spence, The Expeditions of John Charles Frémont, Vol. 2, The Bear Flag Revolt and the Court-Martial, 1973.
  • Kelly, Charles, Salt Desert Trails, Western Printing Co., Salt Lake City, 1930.
  • [Kern, Edward M.] Report of Explorations across the Great Basin of the Territory of Utah for a Direct Wagon-route from Camp Floyd to Genoa, in Carson Valley (1876)], Appendix Q, Journal of Mr. Edward M. Kern of an Exploration of the Mary's or Humboldt River, Carson Lake, and Owens River and lake, in 1845.
  • Nevins, Allan, Frémont--the West's Greatest Adventurer (2Vols), Harper and Brothers, New York, 1928.
  • Scrugham, James G., Nevada: The Narrative of the Conquest of a Frontier Land , American Historical Society, 1935, vol. I, pp. 85-100
  • Senate of the United States, The Proceedings of the Court Martial in the Trial of Lieutenant Colonel Frémont, 1848, and General Order No. 7.
© Bob Graham, 2014

©1999, 2014
Bob Graham