NO. I8 TREE GROWTH AND RAINFALL— CLOCK 2$ 



Table 12 gives the average year-to-year variation of rainfall ar- 

 ranged in two parts, the first of which sets out the variations of 

 jMarch-July and January- August rainfall for the period 1 909-1 941 

 at the several stations. In view of the differences in elevation, the 

 average variation of the rainfall is of the same order of magnitude 



Table 12.— Rainfall 

 Average year-to-year variation 



March-July Jamiary-Augusl 



1909-1941 1909-1941 



Chacon 0.36 0.26 



Black Lake 0.38 0.29 



Taos 0.36 0.25 



Taos Canyon 0.28 O.22 



Las Vegas 0.41 O.34 



Santa Fe 0.35 0.27 



Albuquerque 0.63 0.45 



Santa Fe Albuquerque 



i8so- 189S- i8so. 1898- 



1897 1941 1897 1941 



March- July 0.42 0.33 0.79 e.6o 



January- August 0.39 0.27 0.63 0.44 



Table 13. — Rain jail 

 Average departures 



March-July January-August 



1909-1941 1909-1941 



Chacon 0.22 0.17 



Black Lake 0.25 0.19 



Taos 0.27 0.20 



Taos Canyon 0.20 0.17 



Las Vegas 0.30 0.26 



Santa Fe 0.24 0.20 



Albuquerque 0.43 0.31 



Santa Fe Albuquerque 



1850- 1898- iSso- 1898- 



1897 1941 1897 1941 



March-July 0.33 0.22 0.58 0.40 



January-August 0.30 0.19 0.45 0.30 



as that of the Holman Pass trees. The second part of the table shows 

 the average variation of 1850-1897 to be greater than that of 1898- 

 194 1, which is no doubt to be expected because of the lower average 

 rainfall of the earlier period. Even the interval January-August at 

 Santa Fe has the same decrease in the later period. 



Table 13 gives average rainfall departures. In the first portion of 

 the table the departures for the rainfall of March- July and January- 



