• The Agate Fossil Hills where mammal fossils were excavated in the early 1900's

    Agate Fossil Beds

    National Monument Nebraska

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James Cook looking at a fossil.

One of James Cook's interest was finding the fossils he found in the hills near his ranch.

James Cook

James Cook was born in 1857 in Kalamazoo, Michigan. Just two years later, when his mother died, his father, a Great Lakes captain, placed him and his brother John into separate foster homes.

Ten years later, at age 11 or 12, James left the foster home and went west to Leavenworth, Kansas where he bought a horse for $15.00 and a used saddle for $5.00. He already owned a gun and had established himself as a good shot. He worked for both the cattlemen who gathered Longhorn cattle out of the brush and also for the railroad as a brakeman. In 1874 he participated in his first cattle drive north. He visited Fort Robinson and the Red Cloud Agency in what is now northwest Nebraska, and met Professor O. C. Marsh, an early day paleontologist. He also met, for the first time, Red Cloud, at the Red Cloud Agency, a Lakota Sioux with whom he would enjoy a long friendship.

In 1876 he traveled to Montana to locate good trapping grounds. He made his last trail drive from Texas to Crow Creek, Colorado and from 1878 - 1882 he guided a number of parties on big game hunts in Wyoming. Again he met and visited with early day paleontologists, O. C. Marsh and E. D. Cope, visits which sparked his interest in fossils. In 1882, he traveled to New Mexico and became the manager of the WS Ranch.

James Cook first found the fossils in the Agate area when riding with his sweetheart Kate Graham whose father, E. B. Graham, owned the 04 Ranch in northwest Nebraska. Kate and James married in 1886 and Cook returned to New Mexico. In 1887 James and Kate bought the 04 Ranch from Kate's father and renamed it Agate Springs Ranch for both the Moss Agate in the area and the natural springs of the Niobrara River. They started their ranching business with race horses and cattle. James planted numerous trees at Agate Springs Ranch, many of which are still alive today. These trees form an oasis in a land of treeless mixed grass prairie. He also contacted early-day paleontologists who explored the ranch and found both the Daemonelix Burrows and the 19.2 million-year-old fossils in the Fossil Hills.

James and Kate Cook had two sons, Harold and John. Harold, educated at the University of Nebraska, became interested in fossils and helped the paleontologists when they visited the area. The younger son died at the age of 20 in the flu epidemic of 1918 while attending school in California. James Cook's brother, John, served as postmaster at Agate Post Office for many years.

During his ranching years James remain involved in a myriad of activities. He applied progressive ideas that he learned from the many farming and ranching publications to which he subscribed. He was one of the first ranchers in the area to use irrigation to improve his hay crop. His natural curiosity led him to maintain a lively interest in the area's fossil discoveries. As the Indians continued to visit the ranch, Cooks' friendship with Red Cloud grew. The Indians offered the Cooks gifts, either items made especially for the Cook family or ones of importance to the Lakota Sioux. James Cook preserved these items in the ranch house, hanging some on the walls of his den. People often visited the ranch to view both these Indian artifacts and the fossils. James Cook's desire that these artifacts remain in the area led to the eventual creation of Agate Fossil Beds National Monument.

James Cook died in 1942 at the age of 85 after a long and interesting life. He wrote a book on his life titled Fifty Years on the Old Frontier which is available in the book store at Agate Fossil Beds National Monument.

Harold Cook sitting in front of the Bone Cabin on his homestead which included the Fossil Hills. 1921

Harold Cook in 1921.  He is sitting by the Bone Cabin on his homestead which included the Fossil Hills.

Harold Cook

James and Kate's first son, Harold James Cook, was born July 31, 1887 in Cheyenne, Wyoming. He exhibited an early interest in science, especially paleontology, perhaps fostered by the fossil beds on the ranch. Harold's fossil collecting began in 1892 when he helped Erwin H. Barbour of the University of Nebraska remove a large Daemonelix near the Agate Springs Ranch home. Unidentified skeletal parts were later determined to be pieces of Syndyoceros cooki, named in honor of the young helper.

In 1905, the first of many paleontological field seasons was conducted at the Agate Springs Fossil Quarries by O. A. Peterson for the Carnegie Museum. The young Cook worked with Peterson every moment he could spare from ranch duties, and he read all the pertinent information he could get his hands on. Cook's father also gave permission to Amherst College, the University of Nebraska, and Yale University to collect fossils in closely adjoining deposits, spurring a rivalry between the institutions and adding to Harold's education.

Harold's self-education was so impressive that Professor Barbour invited him to instruct classes in beginning geology in advance of his registration at the University of Nebraska in 1908-09. When Professor Henry Fairfield Osborn brought in a party from the American Museum of Natural History in 1909, he also was impressed by Harold's ability and persuaded him to go to Columbia University to study under Osborn and Dr. W. K. Gregory. Harold worked as research assistant half-time for Dr. W. D. Matthew at the Museum and took 38 hours of class work at the graduate level on Professor Osborn's recommendation; therefore he could cover two year's study in one.

Early in 1910 Harold was forced to return to Agate to help with family and ranch affairs, thus ending his formal education, but not his connections with supporters such as E. H. Barbour, Walter Granger, F. B. Loomis, R. S. Lull, W. D. Matthew and W. J. Sinclair, all of whom contributed to his development. Correspondence with these men and other scientists contributed a major share of the papers in the Cook Library.

Later in 1910, Harold married Eleanor Barbour, daughter of E. H. Barbour, then Nebraska State Geologist. They lived near Agate on Harold's own claim until it was "proved up", (in a small house now called the Bone Cabin), then they moved to the ranch house. Harold and Eleanor had four daughters; Margaret, Dorothy, Winifred and Eleanor. In 1927, Harold and Eleanor were divorced after living apart for several years. Eleanor and the four daughters lived in Chadron, while Harold lived in Denver and at the ranch. Harold then married Margaret F. Crozier from Inglewood, California, but maintained extensive correspondence with his daughters, all of whom became college-educated.

Ranch life did not thwart Harold's scientific exploits. He continued exploring geological formations and paleontological sites on his own time, publishing the results extensively. Although his famous discovery of Hesperopithicus, the ape-man, was a misinterpretation by well-known scientists, his early man discoveries in Oklahoma and New Mexico expanded knowledge for the sciences of paleontology and archaeology alike. Cook was loosely associated with the Colorado Museum of Natural History in the early 1920's, and was appointed Curator of Paleontology in 1925, a position he resigned in 1929 due to differences of opinion with the director and to the pressures of ranch life. During the Depression years, he headed the Historical and Reconnaissance Survey for Scotts Bluff National Monument, and was appointed its' first custodian until mid-1935 when he was removed during political upheavals. Also during the 1920's Harold was appointed and served on the Nebraska State Park Board, and he was President of the Good Roads Association which campaigned for the establishment of Highway 29 the road through Agate.

Did You Know?

James Cook raised horses as well as cattle on the Agate Springs Ranch.

Grasses that make up the mixed grass prairie are excellent for grazing cattle. However, with the low annual rainfall the carrying capacity is 25 acres for one cow and calf. This makes it necessary for ranches in this area to be fairly large. More...