334 REPORT AND ESTIMATE. 
and though by keeping up the River of Lakes to its source, as recommended in the first report, 
a somewhat more level and uniform surface is found, with grades not exceeding forty feet per 
mile, the more direct route travelled by the main train offers no obstructions of consequence. 
The grading on this route will not exceed fifty feet. The line should strike some point on the 
Missouri, in the vicinity of the mouth of the Yellowstone, at the head of navigation for the 
large class of steamers which can run down the Missouri. This point will be in the general 
vicinity of Fort Union, and can be reached by the valley of the Little Muddy. At Mouse, 
Shyenne, Bois de Sioux, and Wild Rice rivers, but best at Red river, all the materials for good. 
bricks are obtained, and it may be found cheaper and better to use brick masonry in the 
neighboring bridges and culverts, though the granite boulders will supply а considerable 
amount. Water can, by reservoir and unimportant aqueducts, be introduced at any point 
desired, and the numerous small lakes on the route will in this way be of service. Even through 
salt water regions fresh water ponds are more numerous than those that are brackish. Prairie 
fires should be provided for by ditching, and as the grass is not generally heavy this will 
prevent all danger to the road work and trains. 
Besides the supply of wood on the rivers and on the Missouri, the road will require supplies 
to be transported from the forest near the Upper Mississippi. But without this it is estimated 
that the supply along the line is sufficient for six years. Coal exists in lower Minnesota and 
Iowa, and an inferior quality was also found on Mouse river. 
FORT UNION TO CROSSING OF MILK RIVER 
From Fort Union the line follows up the favorable valley of the Missouri to Milk river 105455 
miles, and then up the equally fine valley of Milk river for 180 miles further. The bottom 
lands of both are composed of clay and sand, of a nature to become soft and sloppy in wet 
weather, but parched and cracked during the dry season. This section does not offer the best, 
but will afford a fair material for road embankment. The tributary rivers on the north side, 
for which bridges must be erected, are the Great Muddy, Poplar, and Porcupine, all small 
streams, with an average width of sixty feet, the greatest depth where crossed, three feet. 
They will each require eighty feet trusses with two abutments. 
There is, besides, one peculiar feature for which provision must be made in constructing a 
railroad. А+ short intervals, not over eight miles for the whole river-line, narrow canal-like 
channels are found, generally extending from the coulées of the bluffs, dry in summer, but in 
the spring freshets forming the sluices by which the surplus water runs into the river. These 
have an average width of twenty-five feet, with a depth of eight feet, and should be spanned 
with a single timber structure to prevent the accumulation of water which would take place if 
the embankment was filled in across them, and which would in time undermine it. Missouri 
river in the vicinity of Fort Union is about 450 yards wide, and up to Milk river has a valley 
from two to eight miles wide. Its banks are well wooded with cottonwood, and have a small 
quantity of red cedar. The hills on the south side are rough broken bluffs, from three hundred 
to five hundred feet high, and on the north side they also rise abruptly, but are low, the plain 
а few miles back being only from one to three hundred feet above the river. A coarse white 
sandstone crops out of the bluffs, but apparently will not be of use for building. Here the 
Yellowstone coming in will aid in supplying timber, and perhaps stone, from the Black Hills 
and other ranges wooded with pine, which occur some distance up near its course. 
The lignite of this region, traced from the coulées of Mouse river to the headwaters of Milk, 
a distance of five hundred miles, apparently underlies this whole district, in a bed varying 
