Reports of explorations and surveys, to ascertain the most practicable and economical route for a railroad from the Mississippi River to the Pacific Ocean: Vol. 1, Pt. 2

INSTRUCTIONS FOR METEOROLOGICAL OBSERVATIONS.
all are desired to inform themselves in reference to the general objects and results of the expedition, and do all they can to forward the several special operations.
This is the more important, as parties will be frequently subdivided, and several duties thus
be, of necessity, thrown upon the same individual.
ST. LOUIs, May 21, 1853.
MY DEAR SIR: If it would be a possible thing for you to prepare a brief popular notice of the
"Mauivaises Terres" to go into my preliminary report, I shall be glad. That report I mean to
send from Puget sound, about the 15th of December, and your notes I should want a month
earlier.
^ I hope the artist will prove equal to his duties, and that with his assistance you will be able
not only to make sketches of the bad lands, but a tolerable survey, which can be incorporated
into our general map. You will easily connect it with the Missouri river by your two lines to
Fort Pierre and Fort Union.
At Fort Union, should I leave before your arrival, I will leave word as to the two routes I
shall take, with the probable time of being at Fort Benton.
I hope I shall not fail to meet you before you cross the mountains.
Truly yours,
ISAAC I. STEVENS.
Cannot you, in the form of a journal, have a notice which will answer as a preliminary notice.
And I would suggest that if, at Fort Benton, you could let me have your journal, with all your
sketches and topography, the artist and draughtsman of the expedition could at once prepare
them, with other matter, for publication.
M3r. JOHN EVANS, Geologist, St. Louts.
METEOROLOGICAL OBSERVATIONS.
PROGRAMME.
1. Permanent posts for one year, to be kept up for a longer period if additional appropriations are made.
2. Parties in the field to be continued six months; the permanent posts a result of their labor.
3. At permanent posts will be barometrical and hygrometrical observations; also, quantities
of rain and snow will be carefully observed; also, observations as to wind and storms.
4. Parties in the field will all observe for temperature, wind, and storms. Some four main
parties will use the barometer, and, if practicable, make observations as to rain and moisture.
Aneroids to be used for detailed work.
NOTE.-The aurora borealis, temperature of hot springs, &c., will be carefully observed, both
at posts and by field parties.
5. Permanent posts.-Four main posts: 1, Puget sound; 2, Columbia barracks; 3, the
Flathead village of St. Mary's; 4, Fort Benton; and three posts of second order: 5, Fort
Colville or Okinakane; 6, Fort Wallah-wallah; 7, the British trading post at the debouche of
the Marias Pass; and five winter posts: 8, in the Blackfoot trail; 9, in the Marias Pass;
10, in the intermediate pass; 11, 12, two passes in the Cascade range.
NOTE.-The above programme of posts is designed to indicate what it is desirable to accomplish. Circumstances may require changes in it and a reduction of the scale.
INSTRUCTIONS FOR METEOROLOGICAL OBSERVATIONS.
NOTE.-These instructions have been drawn up by Lorin Blodget, Esq., under the direction
of the Smithsonian Institution.
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