202 CALIFORNIA FRUITS: HOW TO GROW THEM 



hose conveys steam to the head of the cylinder of the machine 

 and the other returns the spent steam. The mixed cement and 

 sand is carried to the feeding box (shown in vertical position in 

 the trench), from which it is dropped into the steel pipe form 

 below. Steam pressure is then brought to bear upon it and then 

 cut off by the lever; loose earth is thrown around the steel forming- 

 cylinder as it moves forward and is firmed by the operator's 

 feet ready to sustain the walls of the new pipe as the cylinder is 

 withdrawn from it. More loose earth is thrown over the new 

 pipe, which is allowed to harden before the trench is filled. 



Continuous cement flume is made in a similar manner, the 

 machine working on the surface and the required pressure being 

 given by a strong lever instead of by steam power. Instead of 

 a cylindrical form, one to properly shape the flume is used. After 

 this form is moved and before the cement hardens, grooves are 

 made at intervals in the side walls to insert board clams to raise 

 the water so that it will flow out of zinc tubes with gates, which 

 are also put in place while the cement is plastic. Not only is such 

 flume sometimes cheaper than board flumes, as stated above, but 

 annoyance of leaking and cost of extensive repairs are done away 

 with. 



Board flume and furrow irrigation at Fullerton. 



The Board Flume and the Furrow System. Although in the 

 older regions the cement flume is advancing in popularity, import- 

 ant service will always be rendered by the homemade board flume 

 where suitable lumber is cheap. A detailed account of its con- 

 struction and operation will be widely useful. The following is 

 contributed by Mr. A. S. Bradford, of Orange County : 



I consider the board flume best because it is in many places cheapest 

 and because it will last fifteen or twenty years in California if made of good 

 soft redwood. The common redwood lumber is generally so, but the so- 

 called flume lumber is hard, generally, and will warp the flume out of shape. 

 Even in the common redwood lumber hard pieces will be found, and these 



