DIVISION EIGHT — SCIENCE. 563 



going on here. From Devil's Gate eastward to Monks Hill and beyond 

 there is a subterranean barrier ledge, or " divide," as Judge Eaton calls it, 

 which serves as a submerged dam to hold the waters that are percolating 

 down from the foothills and highland slopes, and compel them to find an 

 outlet at the lowest point of the barrier, which in this case happens to be 

 the Tibbetts springs and flutterwheel springs at Devil's Gate. Next, from 

 Orange Grove Reservoir Hill eastward to Summit and Marengo Avenues at 

 Chestnut street, or above the Santa Fe railroad crossing, there is another 

 barrier ledge which compels the percolating waters to find outlet at the low- 

 est point again, which in this case happens to be at Sheep Corral springs. 

 And a similar underground topography is repeated at Columbia Hill, Ray- 

 mond Hill, and the Glacial Terrace line of bluffs extending thence eastward. 

 Here, then, are our three principal underground basins or lakes. Now, 

 twenty-five or thirty years ago Pasadenaland was a parched, arid, barren 

 desert, all through the "dry season," and from its plains a dry, hot air was 

 radiated or reflected with scorching effect. The mountains held no less water 

 in store then than now, but it all ran to waste down the canyons until lost in 

 their sandy outwashes, instead of being piped out to moisten and fertilize the 

 dried up plains. But since that time the piping has been done, and many 

 thousands of acres that aforetime lay as a scorched plain during four to seven 

 months of the year, are now supplied with moisture, and are covered with 

 vines, fruit trees, flowers, shrubbery, grass lawns, hedges, and trees of stately 

 growth. And thus by necessary consequence the local climate is changed — 

 has become more moist, more humid, and in other ways modified both by 

 increased evaporation from the soil and by the subtle chemistrj^ of vigorous 

 vegetation. The long stretches of railroad trackage and electric wires, the 

 friction of moving trains, the diffusion of their volumes of steam and smoke 

 into the atmosphere, etc., have also worked somewhat to change the electri- 

 cal conditions prevailing, so that the}', too, are different from what they were 

 before this region was wrought upon by the art of man. These are points 

 as to change of climate — both the fact of it and the factors of it. And now I 

 will return to the matter of increased flowage from our springs, as mentioned 

 by Judge Eaton. All the water piped out from the Arroyo Seco and Millard 

 canyon and used either for irrigation or domestic purposes on any lands or 

 lots south of Monks Hill, west of Los Robles Avenue and north of Villa 

 street, is to this area a clear addition of that amount of water which would 

 otherwise have gone to waste down the Arroyo bed, and never touched this 

 land. This volume of water is not lost, except a little by evaporation, but 

 after serving its special uses for man it sinks awa}' into the ground, perco- 

 lates down to the general water bed, and finds outlet again at Sheep Corral 

 springs, thus increasing the flow there. Other areas and other springs are 

 affected in a similar way and by the same processes ; but waters that are 

 used east of upper Los Robles or lower Marengo avenues do not return to 



