cvi GENERAL SUMMARY OF SCIENTIFIC AND 



exchanges with Salt Lake ; but this plan was frustrated by the bad 

 condition of the telegraph line in Montana, which in 1875 was bro- 

 ken in many places. 



The trails thus reconnoitred were from the crossing of the Mouse 

 River ma Fort Totten to Fort Seward on the Northern Pacific Rail- 

 road ; from the Missouri at Fort Buford to the boundary, along the 

 two branches of the Poj^lar River, the meridian trail to Fort Shaw, 

 theRiplinger road along the base of the mountains from the bound- 

 ary to Fort Shaw, the trail from Fort Buford to Fort Benton, and 

 from Fort Benton to the Sweet Grass Hills. In addition, a recon- 

 naissance of the Missouri River was made while descendini? that 

 stream in boats, after completing the field-work for the season, in 

 September, 1874. 



This reconnaissance demonstrated that the generally received 

 estimate of the distance from Fort Benton to Bismarck is too great 

 by about 400 miles, the survey fixing it at 805 miles. 



The country for forty-five miles west of the Lake of the Woods was 

 found to be an immense tamarack swamp only passable when frozen, 

 and necessitating that part of the survey to be made in winter. 

 This was done with some difficulty, the temperature falling as low 

 as 51'' below zero. From this swamp to the treeless valley of the 

 Red River the country is woody and somewhat broken. Of the 

 country to the westward of the Red River very little was previous- 

 ly known. From this stream prairie land extends westwardly for 

 thirty-five miles, the boundary then meeting the first steppe, an an- 

 cient shore-line, now called Pembina Mountain, m.uch broken with 

 ravines and gorges, through one of which, 350 feet deej), the Pem- 

 bina River flows. After crossing this river the land ascends to the 

 upper plateau, about 1500 feet above the sea-level, forming the com- 

 mencement of the Great Plains, which extend for 700 miles to the 

 base of the Rocky Mountains. These plains are in some places quite 

 level, in others imdulating, with numerous hillocks, sometimes 80 or 

 100 feet in height. 



A clayey soil, with some admixture of sand, supports the short, 

 wiry, and very nutritious buffalo grass. The first section of these 

 plains east of Turtle Mountain is seventy miles wide, and is almost de- 

 void of rainfall. Over it are scattered great boulders of granite and 

 limestone from a glacial drift. In crossing Turtle Mountain, a cu- 

 riously elevated and wooded district thirty-five miles wide, the bound- 

 ary crossed sixty-five j^ieces of water, of which twenty-five are true 

 lakes. The effect of this wooded area is very marked in attracting 

 rainfall, while the surrounding plains are suffering from drought. 



For a distance of 138 miles west of Turtle Mountain the Great 

 Plains continue at an average elevation of 2000 feet above the sea, 

 the only break in the monotony being the valley of the Mouse River, 

 one or two miles wide, and 150 feet deep. The boundary then 



