Pe.rsonal and Scientific N^ws. 131 
the past dry season they have been exploited. in;. thei'se.ar;<:h;.,fQrwa,tei: 
and have proved vastly more productive than had been preyiojisly 
believed. The possibility of largely increasing, the. productiveness of 
the valley of Pasadena and the plain of Los AngeJies has Coosequently 
been rendered almost a certainty. The paper concluded with . a few 
notes on the method now in course of adoption for further increasing 
and storing the rainfall. 
On Friday afternoon Prof. E. W, Hilgard, of the agricultur?il de- 
partment of the University of California, spoke on the soils, of the statQ 
and the mode of their formation, the power of.kaolinization,, the effect 
of wind and the origin of adobe. He pointed out the difference .be- 
tween the soils of the dry and the humid regions, maintained that few 
of them needed "liming" or, as it is called, "marling," as there is, usu- 
ally present from i to 2 per cent of lime in some form or other, a 
large part of which is the carbonate. He showed that most of these 
aluminous soils retain the potash resulting from the decomposition 
of the orthoclase and that in many cases this, in the soil of the . sur- 
face alone, amounts to 1200 to 1800 pounds per acre. 
Much of the sandy soil of the state needs only water to becomq 
abundantly fertile, if tolerably free from alkali (chiefly carbonate of 
soda) and the dryness of the superficial soil forces the roots to pene- 
trate it to a much greater depth than roots do in moister regions. In 
consequence of this fact crops which there would be, killed by a long 
drought are here able to survive and even flourish for months without 
any rain. . 
F. M. Anderson, of Berkeley, described the river systern of north- 
ern California and the Klamath mountains. The lattqr, he said, contain 
two sets of flexures at nearly right angles to. each other but not co- 
eval. The streams have the level intermontane areas, in many cases, 
by narrow canyons, indicating an immature topography. Deposits of 
Chico, or Upper Cretaceous, age occur on the north and south sides 
of the Siskiyou river, shaly below and conglomeratic abpve. . 
The lavas of the Cascade mountains are of different ages; the 
oldest eruptive are certainly of a date before the deposition of the 
Chico, or Upper Cretaceous, beds and between them and the later beds 
lie the lone deposits. Near the head of the Siskiyou river there are 
indications of four distinct periods of volcanic activity. Ip some of 
the tuffs are petrified fragments of wood and under some of the 
andesitic beds are specimens of unmineralized wood, bl^ck and 
scorched. This and the drainage of the region which is antecedent in-' 
dicate the very recent date of the eruption. 
H. W. Fairbanks, of Berkeley, spoke on a group of volcanic peaks 
called "The Three Sisters" in central Oregon. . They rise to a hight 
of 10,000 feet, and among them lies a glacier nearly three miles long 
and half a mile wide. The paper was illustrated by a number of slides, 
showing the mountain and the topography of the region. The recency 
of volcanic activity is proved by the superposition of the lava on glaci- 
ated surfaces of the rock and by the presence of a small volcanic cone in 
