246 



FORESTRY AND IRRIGATION. 



June, 



marked that the Hfting proceeds easiest, 

 althotigh at a slower rate, if it is done 

 just about as fast as the water will 

 promptly pour out. To illustrate this 

 I have computed Table No. II, which 



Table I. 



AMOUNT OF WATER LIFTED WITH A TROUGH 



10 FEKT LONG AND I FOOT SQUARE, 



IN CUBIC FEET. 



gives the amount of movement of a 10- 

 foot trotigh from point of stibmergence 

 to pouring level. The lip may be made 

 2 feet long; thus 12-foot lumber will 

 answer very well for construction. 



Table II. 



TOTAL MOVEMENT FROM POINT OF [SUB- 

 MERGENCE TO POURING LEVEL, WITH 

 A lO-FOOT TROUGH. 



A study of the tables shows that it is 

 most effective for lifts of short distances 

 and with the bucket addition. Short 

 lifts are not to be despised. In Holland, 

 to change the current of a canal a lift 

 of one-tenth of a foot is not unusual. 



THE PINUS ATTENUATA (OR PINUS TUBERCULATA) 



AS A WATER CONSERVER. 



By T. p. IvUkens. 



CALAMITIES come upon us as un- 

 expected as they are unwelcomed. 

 The Mission Fathers and the early white 

 settlers little thought of the future pos- 

 sibilities and needs of southern Califor- 

 nia. With conditions as they then 

 were, every acre could be utilized, for 

 there was water for all the land. Then 

 all the mountains were well forested; 

 the trees were cut; then fire and sheep 

 nearly completed the destruction. Tie 

 limit of development is now about 

 reached, unless more water can be had 

 for irrigation. 



There are two ways to increase the 

 water supply, namely, to build storage 

 reservoirs and to clothe our mountains 

 with trees and see to it that they are 

 not destroyed again. Even to build 

 the reservoirs would be tiseless unless 

 the watersheds tributary to them be 

 forested, for the reservoirs would soon 

 become filled with silt if the mountains 

 are bare ; so the only hope for future 

 development is to bring back the for- 

 ests. It is an easy problem to perpetu- 

 ate a forest : When a tree is removed 

 plant another. All conditions are favor- 



