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BULLETIN" 462, U. S. DEPARTMENT OF AGRICULTURE. 
same head as that shown in figure 7. This chart does not show per- 
centages of moisture, but does show the path of the moisture at dif- 
ferent periods of time. The percentage of moisture can be estimated 
very closely from the other chart. This chart also shows that water 
will disappear rapidly below the sixth foot if run too long. The 
lateral distribution is very slight, hardly a foot on either side from 
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Fig. 9. — Curves showing percentages of moisture in the soil at different depths after 
running water at the rate of 10 gallons per minute at Maitland, Fla. 
the edge of the furrow. The furrows are about a foot wide, which 
means that a 3 -foot strip is watered from each furrow. Seventy 
gallons of water per minute was run down this furrow. 
Figure 9 shows the same effect when water is run only 15 minutes. 
It will be seen that there is no waste of water below the third foot. 
A cross section corresponding to this curve would present an appear- 
ance similar to the one shown in chart 8, but would not extend beyond 
the third foot. 
