INSTRUCTIONS FOR METEOROLOGICAL OBSERVATIONS. 
5 
all are desired to inform themselves in reference to the general objects and results of the expe¬ 
dition, and do all they can to forward the several special operations. 
This is the more important, as parties will he frequently subdivided, and several duties thus 
he, of necessity, thrown upon the same individual. 
St. Louis, May 21, 1853. 
My Dear Sir: If it would he a possible thing for you to prepare a brief popular notice of the 
“Mauvaises Terres” to go into my preliminary report, I shall he 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 he able 
not only to make sketches of the bad lands, hut a tolerable survey, which can he 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. 
Mr. John Evans, Geologist , St. Louis. 
METEOROLOGICAL OBSERVATIONS. 
PROGRAMME. 
1. Permanent posts for one year, to he kept up for a longer period if additional appropria¬ 
tions are made. 
2. Parties in the field to he continued six months; the permanent posts a result of their labor. 
3. At permanent posts will he barometrical and hygrometrical observations; also, quantities 
of rain and snow will he 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 he used for detailed work. 
Note. —The aurora borealis, temperature of hot springs, &c., will he 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 accom¬ 
plish. Circumstances may require changes in it and a reduction of the scale. 
instructions eor meteorological observations. 
Note. —These instructions have been drawn up by Lorin Blodget, Esq., under the direction 
of the Smithsonian Institution. 
