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TRANSACTIONS OF THE 



Mammoth Tank and Indio are situated in the eastern portion of San Diego County, and 

 really have a temperature belonging more to the desert counties than to those of the 

 coast. This note will therefore explain the cause of such a difference in its seasonal and 

 yearly average temperature and the smallness of the average seasonal rainfall. 



Table 2 — Showing the Average Temperature and Rainfall for the 



Sacramento Valley Counties. 



The following named counties are represented in Table 2: Shasta, 

 Tehama, Butte, Colusa, Sutter, Yuba, the valley portion of Placer County, 

 El Dorado, Amador, Sacramento, Yolo, and Solano. The lowest tempera- 

 ture below 20° occurred in the following counties: Tehama, Colusa, Placer, 

 Amador, Sacramento, Yolo, and Solano. The lowest being for each count}' 

 named above as follows: 19°, 19°, 16°, 19°, 19°, 19°, and 18°, respectively. 

 The lowest, 16°, was at Colfax, at an elevation of 2,421 feet, which is the 

 very same temperature that was recorded in Los Angeles County, at 

 Ravenna, with an elevation of only 2,358 feet, 63 feet lower than Colfax, 

 which shows well for the Colfax mountain or foothill climate. In the 

 above record it is very remarkable how uniformly the temperature of the 

 great Sacramento Valley is; in a sweep of hundreds of miles and an ele- 

 vation less than a thousand feet we find one uniform minimum tempera- 

 ture of 19° to have been recorded in a record of from ten to thirty-four } r ears. 

 Where is there such a large valley in the northern hemisphere that can 

 begin to compare with our own great valley of the Sacramento which 

 beats the San Joaquin Valley in its escape of low temperatures, for at 

 Kingsburg, Tulare County,' at an elevation of only 301 feet the lowest 

 recorded was 10°. 



