56 CALIFORNIA VEGETABLES 



location of the work in view of the natural conditions and the use 

 to be made of the water, the character of natural banks or bottom 

 which it is designed to use and the best materials at hand for 

 building, as well as the proper form of the construction for safety 

 and efficiency in connection with economical completion of the 

 job. Expert advice is especially necessary where dams are to be 

 built for closing natural waterways for such efforts involve the 

 handling of volumes of storm water which a farmer may have 

 little conception of, though he may have grown up on the site. 



The excavation of a small reservoir to collect water from 

 sources wholly apart from a natural water course is a simpler 

 proposition and can be easily done with farm experience and ap- 

 pliances, and on this work some suggestions may be offered. 



First: Location is governed by local factors, but it should 

 be at sufficient elevation to deliver the water freely at whatever 

 point is involved in its use. 



Second: Its area will depend upon the prospective water 

 supply. If this is ample, do not make the pond too small. A 

 circular reservoir with an average depth of four feet through a 

 circular space forty feet in diameter, will hold water enough to 

 cover about two-thirds of an acre two inches deep. This will 

 amount to a good soaking of a good-sized farm garden, and is 

 probably as small a dirt reservoir as it will be worth while to 

 make. For smaller storage wooden or galvanized iron tanks can 

 well be used. 



Third: In shape the circle is easiest to mark out and con- 

 struct symmetrically and encloses the greatest possible area with 

 the least length of bank, but on a small figure it may be a little 

 easier to handle teams and scrapers on an oval. 



Fourth: A fairly retentive loam free from rock or rubbish, 

 upon a clay subsoil, favors the easiest and cheapest construction 

 of a dirt reservoir because with careful construction it can be made 

 water tight without using other materials. Clay is disposed to 

 leak through cracking and sand will neither hold shape nor water. 

 Clay and clean sand mixed, forms an ideal material. 



Fifth : The earth surface under both the pond and the banks 

 must be thoroughly cleaned of all sods and trash and the whole 

 area plowed and harrowed well to make it as fine as possible. 

 The dirt should not be dumped on the old surface to start the 

 bank. When the whole is plowed and harrowed the scraper can 



