PREFACE. 
ix 
were used up to this point, and a very thorough collection of the Natural History products was made, and 
sent back by Lieut. Saxton, who, coming eastward from the Pacific coast, met them there and descended 
the river in a boat to Fort Leavenworth. 
Dr. Evans, geologist to the eastern division, who had crossed Nebraska in a northwest direction from 
Fort Pierre, also met them there and contributed some specimens to the collections. 
Leaving Fort Benton September 22, Dr. Suckley traveled with the main party by way of Hell Gate 
Pass to St. Mary's in Bitter-root Valley, where he arrived on the 29th, making the distance of two hund- 
red and thirty-five miles in that time. This rapid riding over a more difficult country than before, 
and without wagons for transportation, prevented large collections being made in the most interest- 
ing portion of the route, yet the few specimens preserved proved especially valuable. The country 
is about half wooded, and rich in vegetable and animal life, particularly west of the Rocky Mountains. 
The deficiencies of this part of the route were afterwards supplied in a great measure by the collections 
made by Lieut. Mullan in Bitter-root Valley during the following year, and sent to Dr. Suckley. 
At this point Dr. Suckley received orders to make an exploration by water down Clark's Fork and the 
Columbia. He left St. Mary's, October 15, in a skin boat made of three bullock's hides, in company 
with two white men and an Indian. They traveled in this way for twenty-five days, reaching Lake 
Pend'Oreilles, where they left the boat and crossed by land the distance of sixty miles to Fort Colville, 
arriving there November 13. The diflSculties and exposures of this trip so late in the season, prevented 
the collection of many specimens, but the numerous and important observations made, are found in his 
report, published in vol. I. Pacific Eailroad Ecports, p. 291, 1854. Obtaining wooden canoes 
at Fort Colville, Dr. Suckley continued down the river and arrived at Fort Vancouver, December 6, nine- 
teen days later. A few days after he proceeded to Puget's Sound, and receiving an appointment as As- 
sistant Surgeon United States Army, was stationed at Fort Steilacoom through the winter, making one 
voyage down the Sound the following March, as far as the Straits of Fuca. Here ended his ofiScial con- 
nection with the railroad exploration. 
The western division of the expedition under the command of Brevet Captain George B. McClellan, 
U. S. Engineer, went from New York by the Panama route to Fort Vancouver, W. T., where Dr. Cooper, 
the surgeon and naturalist arrived June 14, two weeks in advance of his collecting equipment. During 
the four weeks ensuing, while the party was being organized, and the supply train of Lieut. Saxton 
fitted out for his journey to meet the eastern division in the Rocky Mountains, little could be collected. 
On July 18 the party left Fort Vancouver, badly provided with the means of transportation, which was 
confined to pack-horses and mules of inferior quality and very heavily laden. For this reason the col- 
lections were limited to the most interesting objects until the party reached the summit of the Klickatat 
Pass on Aug. 6, having made only 93| miles, at a rate of 6^ miles a day. 
Two days were spent in the mountain pass, but too far from the Alpine peaks to reach any of their 
peculiar products. Descending the eastern slopes, Aug. 10, the route turned northward, and on the 20th 
a stationary camp was pitched near the " Wenass," a branch of the Yakima River. Here an attempt 
was made to obtain fresher and better animals from Fort Steilacoom, and many of those broken down 
were taken there by Lieut. Hodges ; but finding none in exchange, the only resource was to send back the 
military escort and others, by which means the party was reduced nearly one-half. Dr. Cooper was 
obliged to save his horse by exploring the neighboi-hood on foot only. 
Sept. 3, the stationary camp was removed 14| miles, to the valley of the main Yakima, where it re- 
mained two weeks longer — detached parties exploring, during that time, the whole course of that river. 
A few specimens were brought in by Mr. Gibbs, and Dr. Cooper collected a considerable number near 
