UNITS EMPLOYED.
Reading edition
The units used in this work are uniformly those in common use in America, with the single exception of data in regard to sand-grain sizes, which are given in millimeters. The American units were not selected because the author prefers them or considers them particularly well suited to filtration, but because he feared that the use of the more convenient metric units in which the very comprehensive records of Continental filter plants are kept would add to the difficulty of a clear comprehension of the subject by those not familiar with those units, and so in a measure defeat the object of the book.
TABLE OF EQUIVALENTS.
Unit. Metric Equivalent. Reciprocal.
Foot 0.3048 meter 3.2808
Mile 1609.34 meters 0.0006214
Acre 4047 square meters 0.0002471
Gallon[1] 3.785 liters 0.26417
1 million gallons 3785 cubic meters 0.00026417
Cubic yard 0.7645 cubic meters 1.308
1 million gallons per acre daily 0.9354 meter in depth of water daily 1.070