46 CALIFORNIA VEGETABLES 



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

 at sufficient elevation to deliver the water freely at whatever point 

 its use is desired. 



Second : Its area will depend upon the prospective water 

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

 cular reservoir with an average depth of four feet through a circular 

 space forty feet in diameter, will hold water enough to cover two- 

 thirds of an acre two inches deep. This will amount to a good soak- 

 ing 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 construct 

 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 resorvoir 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 be started, 

 moving the dirt from the center to the banks, and each scraper load 

 should be spread and lumps broken with a shovel at once, leveling 

 and filling hoof prints so that all tramping or pressure of the scraper 

 in passing may tend toward even packing of the soil. All spots not 

 reached by the team or tools should be tramped by the shoveler so 

 that no loose dirt may be covered. This work should be continued 

 all through the building. The harrow should follow the plow in the 

 bottom before the scraper moves the dirt to the bank. 



Sixth: The outflow pipe should be put in early. A wooden 

 box is often used having an interior space of six by six inches, 

 but a four or six inch lap-welded steel or cast iron pipe is vastly 

 better. It should have an elbow turned up on the inside so that 

 a plug with a long handle can be used to open or close the exit. 

 A valve is better than a plug, but it costs more. The pipe should 

 be bedded in a mass of concrete so that it will not be loosened by 

 working the outlet plug or valve. 



Seventh: The width of the embankment is governed by its 

 height. The slopes with the best of earth should not be less than 

 two feet horizontal to one foot vertical on the inside; and if the 

 material is light, three to one on the outside will be none too much. 



Eighth : The bottom and inside of the reservoir banks should 

 be well puddled. This 'is done by thorough plowing and harrowing 



