222 REPORT ON DEAD COLT HILLOCK LINE. 
D. 
SURVEY FROM THE MISSISSIPPI TO THE BASE OF THE MOUNTAINS. 
10. Report UPON THE *“‘ DEAD COLT HILLOCK”’ LINE, BY LIEUT. C. GROVER, U.S. A. 
Fort Union, August 7, 1853. 
Sm: On the 25th of June ultimo, I had the honor to receive the following orders from your 
office, viz: 
“ NorTHERN Paciric R. R. Exproration, Camp Marcy, Pike Lake, 
June 25, 1853. 
“Dear Srr: You will, in charge of a detached party consisting of twenty-one picked men, 
two wagons and thirty-three animals, leave the Red River trail at this point, and crossing the Bois 
des Sioux near Lake Travers, and proceeding in the general direction of Dead Colt Hillock, con- 
tinue your course to the mouth of the Yellowstone. Make the best survey of the country the 
means placed at your disposal will furnish. With the Schmalcalder compass, odometer, and the 
meteorological instruments, you will be able to get a reliable line and profile of your route. It 
is desirable, if practicable, to connect your line with Lieutenant Donelson’s survey of the Missouri, 
at some eligible point, as Fort Berthold. Whether, and at what point this shall be done, is left 
to your own judgment. The great necessity is to reach the Yellowstone, and be in readiness for 
the work beyond. Your party has been selected with care, to enable you fully to accomplish its 
purposes; and I have the most entire confidence in its complete success. I shall continue on a 
more northern course, and, operating much with detached parties, [ hope the labors of the ex- 
pedition will result in a good exploration of the country from the Missouri to the Miniwakan 
lake. Lieutenant Quaker has instructions to survey the Missouri to the mouth of Milk river, 
and the country north of Fort Union, from White Earth river (western boundary of Minnesota) 
to the Porcupine. I trust you will reach Fort Union before the main party; in which case, 
assume coramand of the whole force brought together there, and communicate directly with the 
Secretary of War, should an opportunity to send letters occur. 
“‘ We shall undoubtedly hear of each other frequently on the route, and through Indian runners 
have the means of communicating with each other. With vigilance and firmness I have no fear 
of stampedes or disaster; and it is important that great care should be taken as to placing the 
least reliance upon any rumors of the sort. They will instantly be spread without the least 
foundation for them. 
“ Lieutenant C. Grover, 
“4th Artillery, U. S. A.” 
Pursuant to the above order, my detachment having been organized, 1 left Pike lake, about 
eight o’clock a. m. on the twenty-fifilh day of June, and took up a course of north seventy-eight 
(78°) west. The general course I kept to a series of lakes known as Moose Island lakes, whence 
circumstances rendered it advisable to deflect some distance to the south, and follow up the east- 
ern bank of Lake Travers and Bois des Sioux river to the crossing contemplated in my instruc- 
tions. Between Pike lake and the Pomme de Terre river a more sudden declination occurs, 
leaving a valley from a mile to a mile and a half wide. The currents of these streams are rapid, 
and their bottoms sandy, with a width of about twenty (20) yards in ordinary stages of water. 
To the west of the last named river, for a few miles, this uneven country continues, gradually 
falling off to an almost perfectly level prairie, to the Bois des Sioux, with the exception of a slight 
rise near the Rabbit river. West of the Bois des Sioux, which is a broad, marshy stream, but 
with a sandy bottom at some few points, a similar level prairie extends to near Dead Colt Hillock, 
between which and James river on a direct line the country is high and bluffy. But by deflect- 
ing to the south, passing between Dead Colt Hillock and Lake Kandiotta, and crossing the 
