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WATER MEASUREMENT. 



The cultivator who handles water must be able to determine 

 fairly accurately the amount of water needed for a crop on a given 

 soil, and a few figures in relation to the measurement of water will 

 be helpful in calculation : 



1 gallon of water weighs lOlbs., and measures 277,274 cubic inches. 

 1 cubic foot of water weighs 62^38., and contains 6 gallons, 

 1 ton of water contains 224 gallons, and measures 36 cubic feet. 



1 inch of water over an acre of land weighs 101 tons, and therefore 

 means 22,624 gallons, an amount which would be held in a 

 tank with a 3,600 cubic foot capacity. 



A miner's inch is the amount of water running from a hole one inch 

 square Avith a head pressure of 6 inches in one second or one 

 minute. 



WATERS FIT FOR IRRIGATION. 



Water is the universal solvent, and no water except that 

 trickling from the condenser of a distilling apparatus is absolutely 

 pure in its natural condition. 



Thus rain water, which is considered the purest of all, washes down 

 from the air impurities which to a great extent constitute valuable 

 plant food. In close proximity of the sea coast, for instance, 30 to 

 401bs. of common salt to the acre are brought down annually by the 

 rain. Of ammonia 2 to 101bs.,and of sulphuric acid 10 to 201bs. are 

 added from the same source to every acre of land in localities 

 favoured with a fair amount of rain. 



Of stream water some prove better than others when used for 

 irrigation, and they vary according to the amount of substances 

 they carry either in solution or in suspension. 



Well water is, as a rule, even more highly mineralised than stream 

 water, and is often injurious to vegetation,, especially in the Eastern 

 and inland districts, where it is not unfrequently unfit for con- 

 sumption. 



Taste is the readiest means of ascertaining whether water is fit 

 for domestic or irrigation use. 



A crystal clear well water often proves worthless for irrigation 

 purposes, whereas a spring or a well well-stocked with, aquatic 

 plants and luxurious vegetation, and where stones at the bottom 

 are covered with green slime, always holds water fit for irrigation. 



The best indicator of the fitness of water for irrigation is the 

 palate, and when the taste is decidedly mawkish it is advisable to 

 have a sample analysed before going through the trouble and the 

 cost of providing for its lifting and cost of distributing it on the 

 ground. An analytical statement is often perplexing until the 

 array of figures is understood. 



