METEOROLOGICAL OBSERVATIONS. 
585 
LETTER OF LIEUTENANT MULLAN, U. S. A., TO GOVERNOR I. I. STEVENS, TRANSMITTING METEOR¬ 
OLOGICAL REGISTER KEPT IN THE ST. MARY’S VALLEY. 
Olympia, W. T., December 17, 1854. 
Sir : I have the honor herewith to transmit a Meteorological Register kept in the St. Mary’s 
valley from the 8th of October, 1853, to 18th of September, 1854. I have, during the last year, 
submitted for your perusal monthly registers from time to time, which have been transcripts from 
this register. You will find the register full as to details, and which renders unnecessary my re¬ 
ferring to it except in a general manner. It was found in the St. Mary’s valley that snow did 
not fall during the last winter to a greater depth than from three to four inches, after several suc¬ 
cessive falls of snow. The winter, with the exception of a few days in December and January, 
was remarkably mild. During those days, however, the cold was intense. The thermometer in 
the St. Mary’s valley ranged as low as twenty-eight degrees below zero. During my examina¬ 
tions through the mountains—and I was travelling every month except February—I did not find the 
snow at any point deeper than fifteen inches, and this was on the summits of the Snake river 
mountains on the south, in December and January, and the summits of the main divide of the 
Rocky range in March. Though, I must say, I crossed at the most favorable points of the two 
ranges, I am convinced that at other points the snow fell to much greater depths; but, of course, 
at points never travelled in the winter season. 
The points I refer to are the passes which I deem practicable for travelling with horses at all 
seasons, even mid-winter. 
If the results of last winter are taken as data, I consider the problem of the snows of the 
mountains solved. Still I deem it essentially necessary, in view of the great interests depending 
upon this important problem, that further and minute observations should be made at different 
points in the mountains. I might suggest, in addition to the St. Mary’s valley, the Coeur d’Alene 
mission, the Upper Pend d’Oreille mission, the Spokane prairie, at the ranche of Messrs. Owen 
and Gibson, and also at Forts Benton and Wall ah-Wallah. The latter is not essentially neces¬ 
sary, but would afford a great facility and means of comparison with points in the mountains. A 
thermometer, with a register, might be kept at Mr. Craig’s, a man of sufficient intelligence, and 
who, I have no doubt, would feel an interest in the matter ; together with the different Indian 
agencies that may hereafter be established throughout the territory east of the Cascade range of 
mountains. Having reported to you several times on the character of the winter and snows, I 
deem any further details unnecessary. 
With respect, your obedient servant, 
J. MULLAN, 
Lieutenant U. S. Army. 
Governor Isaac I. Stevens. 
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