10 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 1 10 



merits in the road, laying out new sections over better terrain or 

 shortening the distances to be traveled, decreasing the number of 

 necessary river crossings. When a new section of road was to be 

 laid out, Sohon moved ahead with a small party to mark out the 

 road and make detailed observations on the features of the country. 

 The party wintered at Cantonment Wright at the junction of the 

 Hell Gate and Big Blackfoot Rivers. In June 1862 Sohon was in 

 charge of the main party which followed Lieutenant Mullan's advance 

 party west. Lieutenant MuUan disbanded his expedition at Walla 

 Walla in late August, 1862. 



After more than 4 years of work, the wagon road was completed. 

 It was the first road to connect the head of navigation on the Missouri 

 with the head of navigation on the Columbia. Some 624 miles long, 

 and from 25 to 30 feet wide, it could be traveled by lumbering wagons 

 in 57 days, by pack animals in 35 days. Although originally intended 

 as a military road to transport men and supplies to the posts of the 

 far northwest, it was used primarily as a highway for travelers and 

 settlers, and for the transport of freight to and from the northwest. 

 "The Mullan Road," as it was commonly called, rendered important 

 service to the settlement of the far northwest in the days before the 

 railroads reached that section. 



Mr. Sohon journeyed to Washington with Captain Mullan after 

 the field season of 1862. In Washington he probably assisted Mullan 

 in the preparation of data, maps, and illustrations for his official 

 report on the project. The "Report on the Construction of a Military 

 Road from Fort Walla Walla to Fort Benton" was published in 1863. 

 It is illustrated by 10 colored lithographic reproductions of original 

 drawings by Gustavus Sohon, all of which are erroneously labeled 

 "C. Sohon." (A list of these illustrations appears in the Appendix, 

 pp. 67-68.) Three of the large folding maps at the end of this report 

 credit Gustavus Sohon as one of the civil engineers who contributed 

 material to their compilation. On the two maps which show the location 

 of the pass between the Coeur d'Alene and St. Regis Borgia Rivers, 

 the name "Sohon Pass" is given to the location. Lieutenant Mullan 

 named the pass in honor of Gustavus Sohon who made the first 

 topographical map of it. Father De Smet crossed this pass in 1863, 

 and referred to it as "Sohon Pass." (Chittenden and Richardson, 1905, 

 vol. 3, p. 795.) However, when the railway was built over the 

 Coeur d'Alene Mountains in 1889, it crossed the summit by another 

 pass of nearly equal altitude, i^ miles northeast of Sohon Pass. The 

 name Lookout Pass is now applied to the one followed by both the 



