10 RECONNAISSANCE FROM CARROLL, MONTANA, 
I left Saint Paul on the evening of June 30, in obedience to Special Orders No. 110, series of 1875, 
Departure from from headquarters Department of Dakota, and proceeded, via the Northern Pacific 
Queers Railroad, to Bismarck, its western terminus, on the Missouri River. 
[Special Orders No. 110.) 
HEADQUARTERS DEPARTMENT OF Dakota, 
7 Saint Paul, Minn., June 14, 1875. 
Capt. William Ludlow, chief engineer of the department, will, on July 1 proximo, proceed, via the Northern Pacific 
Railroad and the Missouri River, to Carroll, Mont., and make a reconnaissance of the route from 
that place to Camp Baker. Havivg completed this duty, he will proceed to the several posts in 
the district of Montana, and determine their latitudes and longitudes. He will also, if time permits, make a recon- 
naissance from Fort Ellis to the Yellowstone Park. Captain Ludlow is authorized to take with him his assistant and 
the enlisted men of engineers under his command. He is also authorized to take with him a geologist and such other 
scientific gentlemen, not exceeding four in all,as may desire to accompany his party. The commanding officer of the 
District of Montana will furnish escorts to Captain Ludlow from point to point, wherever, in his judgment, it may be 
necessary, sending a party to Carroll for that purpose; the transportation being sufficient to furnish one wagon, one 
ambulance, and five saddle-horses for use of Captain Ludlow’s party. 
By command of Brigadier-General Terry: 
Orders. 
O. D. GREENE, 
Assistant Adjutant-General. 
(Special Orders No. 127.] 
HEADQUARTERS DEPARTMENT OF DakoTa, 
Saint Paul, Minn., July 7, 1875. 
& * 
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Ill. The Quartermastey’s Department will empioy one civilian guide and scout to accompany the reconnaissance 
under Capt. William Ludlow, United States Engineers, authorized in Department Special Orders No. 110, current 
series. He will be paid at the rate of $75 per month for the time he is actually employed, and will be furnished with 
transportation by steamboat for himself aud horse from Bismarck to Carroll and return. The acting assistant quarter- 
master at Fort Abraham Lincoln will take him up on his “ Report of persons and atricles.” 
IV. Second Lieut. R. E. Thompson, Sixth Infantry, will report to Capt. William Ludlow, Engineer Corps, for duty 
as topographer, with the reconnaissance under the latter-named officer, authorized by Special Orders No. 110, current 
series, from these headquarters. 
By command of Brigadier-General Terry: 
O. D. GREENE, 
Assistant Adjutant-General. 
My party consisted (beside my brother, Mr. Edwin Ludlow, of New York, and assistant, Mr. W. 
Composition ofthe H- Wood) of Messrs. George Bird Grinnell and Edward 8. Dana, both of Yale Col- 
party. lege, who had come out to Saint Paul upon my invitation for the purpose of join- 
ing me. 
These gentlemen traveled at their own expense, receiving no compensation for their services; and 
Messrs. Grime! I cannot but consider myself extremely fortunate in having induced them to 
and ec «accompany me as special assistants. Mr. Grinnell would report upon the paleon- 
aesietents. tology and zoélugy and Mr. Dana upon the geology of the country passed over. 
The reports attest their zeal and industry, as well as the fullness of their qualifications for, and 
conscientious devotion to, their voluntarily-assumed tasks. 
Special Orders No. 121 directed my detachment of engineer soldiers, consisting of Sergeants 
Becker and Wilson and five men, to report to me at Carroll for surveying purposes. 
At Bismarck, the party was increased by the addition to it of Lieut. R. E. Thompson, Sixth Jn- 
Lieutenant Thomp- fantry, who was to accompany it as topographer and general assistant, and of 
sorde added tf tte © Carles Reynolds, a well-known frontiersman, who was to act as guide and hunter 
party. for the expedition. 
The instruments taken on the trip were asmall Wiirdemann transit-theodolite, No.94; a Spencer 
Sentai ala Browning & Co.’s sextant, No. 6536; a Gambay & Son reflectin g-circle, No. 212; and 
onthe reconnais. two chronometers, a mean solar of Arnold & Dent, No. 1362, and a sidereal of Bond 
sankey & Sons, No. 202. These instruments, with the exception of the circle, had been 
used on the reconnaissance to the Black Hills of the previous season, and were known to be good. 
In addition were four odometers, two thermometers, two aneroid barometers, and an odometer-cart, 
constructed for the purpose of measuring distances. 
