328 METEOROLOGY. 
parts-of the interior of the continent southward and the coast of southern California we have a 
decided advantage. 
Spring. | Summer. Autumn. Winter. Year. 
Inches. Inches. | Inches. Inches. Inches. 
Laredo, Texas 4.07 7.33 Г 5. 06 2.20 18. 66 
ы Tu, New MEXICO exuosé cie» 022. 0.70 3. 56 5. 25 1.70 11. 21 
Albuquerque . 1.10 5.45 2.07 0. 80 9. 42 
Fort Yuma 0. 27 1. 30 0. 86 0. 72 8.15 
San Diego, California 2.74 0. 55 1.24 5. 90 10. 43 
Monterey, California > 4.43 0.21 1. 65 5. 91 12. 20 
Benicia; Ualiforhla сезт» a tees eee ee des 6. 40 0.01 2. 65 1.56 16. 62 
All the interior of California has about the same amount as the last place quoted. 
In the comparison of climate, as deduced from these observations in the vicinity of the Rocky 
mountains and thence to the Pacific, it must be remarked that the means of the series of 
observations at 7, 2, 9 will not approach so near the means of the twenty-four hours as they do 
in countries of more uniform surface. As is well known the nights are always cold among 
mountain ranges, no matter how high the temperature may rise during the day. The only 
series of observations from which corrections for the mean temperature of the twenty-four 
hours can be approximately deduced is that made at Sacramento, California, by Dr. T. M. 
Logan, and published in the Smithsonian Report for 1857. These have not been extensive 
enough to warrant their adoption as constant, but they give a good idea of this great diurnal 
range in the thermometer. From his series of hourly observations, made on only one day in 
each month, it appears that the hours when the temperature approaches nearest the mean for 
the day аге: in— 
Spring, 7.30 to 9.53 a. m.; 8.16 to 9.19 p. m. 
Summer, 7.33 to 8.54 a. m.; 8.6 to 8.47 p. m. 
Autumn, 8.42 to 10.47 a. m.; 9.55 to 12.35 р. m. 
Winter, 10.45 to 11.30 a. m.; 9.30 to 12.30 p. m. 
"The difference between the hourly mean and that derived from the three daily observations 
is, for spring, —1° 2; summer, —1° 2; autumn, +0° 2; winter, +0° 1; year, +0° 6, to 
be added or subtracted from the mean of observations made at the hours of 7, 2, and 9. At 
Rochester, New York, it has been ascertained, by a long series of careful observations made 
by Professor Dewey, to be, for observations made at the hours of 7, 2, 9, spring, —0? 8; 
summer, --09 8; autumn,—0° 5; winter,—0° 5; year,—09 6. If, as is most probable, 
the Sacramento corrections approach nearest to the truth for the interior of Washington Terri- 
tory, we have an unexpected additional testimony in favor of its winter climate, as well as its 
mean annual temperature. , 
The deduction of 1°.2 from the summer heat is, however, less than was to be expected. 
The cold nights show their principal effects on vegetation, in the fact that Indian corn, and 
perhaps some other crops, which are the chief products between the latitudes of New York and 
Baltimore, where the summer heat is similar, are not certain crops, though cultivated even at 
Fort Colville and at other places to the southward. They succeed well, however, in Walla- 
Walla and the Nez Percés country. 7 А 
Dr. Logan says of Sacramento: “ Опе of the most striking features of the climate is the 
greatest reduction of temperature after the hour of maximum elevation. However high the 
