. The encyclopedia of practical horticulture; a reference system of commercial horticulture, covering the practical and scientific phases of horticulture, with special reference to fruits and vegetables;. Gardening; Fruit-culture; Vegetable gardening. IRRIGATION 1171 hours will cover one acre two feet deep, equal to two acre-feet. Approximate Estimate of Water It requires an engineer with proper instruments to obtain an accurate esti- mate of the amount of water flowing in a ditch, but an approximate estimate may be made as follows: Secure the cross section by measuring the depth in a number o
. The encyclopedia of practical horticulture; a reference system of commercial horticulture, covering the practical and scientific phases of horticulture, with special reference to fruits and vegetables;. Gardening; Fruit-culture; Vegetable gardening. IRRIGATION 1171 hours will cover one acre two feet deep, equal to two acre-feet. Approximate Estimate of Water It requires an engineer with proper instruments to obtain an accurate esti- mate of the amount of water flowing in a ditch, but an approximate estimate may be made as follows: Secure the cross section by measuring the depth in a number of places at given distances across the stream, adding them together and dividing by the number of measure- ments taken. This will give the average depth, which should be multiplied by the width of the stream at the surface. This will give the number of square feet in the cross-section of the stream. Then measure off on the ditch bank any dis- tance, say 20 feet parallel with the cur- rent. Throw a stick into the center of the stream where the water is running at its greatest velocity and far enough above the first measurement so that the stick will have time to acquire the same velocity as the stream before it reaches the point of the first measurement. Take the time in seconds required for the stick to float the distance measured. This will give the velocity of the mid-current. Eighty-three per cent of this will give the average mean velocity of the whole stream. Multiplying the number of square feet in the cross-section by the velocity of the stream, in seconds, will give the number of cubic feet per second of time. In the case of small ditches reduce all measurements to inches. On account of the filamentous or thread-like character of water there is a tendency to compres- sion as it passes through an orifice. After the discharge it continues to converge so that the section of the water after leaving the orifice is smaller than the orifice from which it discharges. This is be
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Keywords: ., bookcentury1900, booksubjectfruitculture, booksubjectgardening
