| 1 = _Altitude_ (_feet_) | | 2 = _Years_ | | | | -- 3 years -- -- 5 years -- | | 1 2 (_r_) (_r_/_e_) (_r_) (_r_/_e_) | | ---- --------- ------ ------- ------ ------- | | Sacramento, 70 1861-1910 +0.386 4.7 +0.352 4.2 | | Colfax, 2400 1871-1909 +0.311 3.1 +0.308 3.0 | | Summit, 7000 1871-1909 +0.099 0.9 +0.248 2.3 | | Truckee, 5800 1871-1909 +0.229 2.2 +0.337 3.3 | |[A]Boca, 5500 1871-1909 +0.482 6.4 +0.617 8.6 | | Winnemucca, 4300 1871-1909 +0.235 2.2 +0.260 2.4 | | San Bernardino, 1050 1871-1909 +0.275 2.7 +0.177 1.8 | | | | C. RAINFALL FOR 3 YEARS AT CALIFORNIA AND NEVADA STATIONS, | | 1871-1909 | | | | (_r_) (_r_/_e_) | | ------ ------- | | Sacramento and San Bernardino +0.663 10.7 | | San Bernardino and Winnemucca +0.291 2.8 | | | +-------------------------------------------------------------------+ The correlation coefficients for the sequoia growth and the rainfall at Jerusalem are given in Section A, Table 4. They are so high and so consistent that they scarcely leave room for doubt that where a hundred or more sequoias are employed, as in Fig. 5, their curve of growth affords a good indication of the fluctuations of climate in western Asia. The high coefficient for the eleven trees measured by Douglass suggests that where the number of trees falls as low as ten, as in the part of Fig. 4 from 710 to 840 B. C., the relation between tree growth and rainfall is still close even when only one year's growth is considered. Where the unit is ten years of growth, as in Figs. 4 and 5, the accuracy of the tree curve as a measure of rainfall is much greater than when a single year is used as in Table 4. When the unit is raised to thirty years, as in the smoothed part of Fig. 4 previous to 240 B. C., even four trees, as from 960 to 1070, probably give a fair approximation to the general changes in rainfall, while a single tree prior to 1110 B. C. gives a rough indication.