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for a supplement of that food in the shape of manure, it will, 
when producing, say, four tons of fruit, when put under intensive 
culture, with the aid of irrigation, show signs of falling off much 
quicker than it would otherwise have done. 
The belief that a crop is all right because it has been irri- 
gated, unfortunately proves only too often a delusion. Unless the 
operation can be carried out at a reasonable cost, with suitable 
water, on well-drained ground, properly manured, and provided the 
operation is not overdone, irrigation cannot be profitable. It is 
also essential, when orchards and vineyards are concerned, that 
the pruning and thinning operations should receive proper atten- 
tion, and that pests and blights should be vigorously suppressed 
and not allowed to share with the owner the surplus crop which 
irrigation carried out under favourable circumstances always en- 
sures. 
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 caleulation :-— 
1 gallon of water weighs 10lbs., and measures 277 cubic 
inches. , 
1 cubic foot of water weighs 624lbs., and contains 644 gal- 
lons. 
1 cubic yard contains 169 gallons of water. 
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 eubie foot capacity. A 
square tank 15ft. x 15ft. x 15ft. would about hold this 
quantity or, nearer still, a tank 18ft. x 20ft. x 10ft. = 
3,600 cubic feet. 
A miner’s inch is the amount of water running from a hole 
one inch square with 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 trick- 
ling 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 in- 
stance, 30 to 40lbs. of common salt to the acre are brought down 
