[15]. Eng. Record, Vol. 74, 1916, p. 263.

[16]. Professional paper No. 46, United States Geological Survey, 1906, p. 97.

[17]. United States Geological Survey, Water Supply paper No. 257, 1911.

[18]. From Eng. Cont., Vol. 41, 1914, p. 698.

[19]. Max. represents only the average maximum, not the greatest maximum.

[20]. Eng. News-Record, Vol. 80, page 1233, 1918.

[21]. Infiltration of Ground Water into Sewers. Transactions of the American Society of Civil Engineers, Vol. 76, 1913, p. 1909.

[22]. A comprehensive discussion of rainfall formulas will be found in Vol. 54 of the Transactions Am. Society of Civil Engineers, 1905.

[23]. Formula devised by H. E. Babbitt from Allen’s 25–year curve.

[24]. See Note under Table 14.