[22]. Fitzgerald, and Foss, Report Boston Water Board, p. 86, 1893.

[23]. Forbes, F. B., and Pratt, G. H. The determination of carbonic acid in drinking water: J. Am. Chem. Soc., Vol. 25, pp. 742–56, 1903.

[24]. Fowler, G. J. Sewage works analyses, pp. 21–37, John Wiley & Sons, New York, 1902;

[24a]. pp. 31–4;

[24b]. pp. 58–60;

[24c]. pp. 86–9;

[24d]. pp. 89–95;

[24e]. pp. 96–7;

[24f]. pp. 98–100.

[26]. Fowler, G. J. Univ. of Manchester Lecture, March, 1904, Pamphlet, p. 7.