^{page 456 note 1} U. S. Bureau of Soils, Bulletin 50.

^{page 456 note 2} Ibid., Bulletin 10.

^{page 456 note 3} Ibid., Bulletin 38.

^{page 456 note 4} Memoirs of Indian Agric. Dept. Pusa. Chemical Scries, Vol. I. No. 6.Google Scholar

^{page 457 note 1} I.e. the material removed by 2 % NaOH.

^{page 458 note 1} U. S. Bureau of Soils, Bulletin 51: “Absorption of gases and vapours by soils”.

^{page 466 note 1} This curve has not been drawn above 11 % in the diagram, as the portions A and B were only moistened up to 12 %–14 %.

^{page 469 note 1} Leather, , Memoirs Agric. Dept. Pusa. Chem. Series, Vol. I. No. 6.Google Scholar

^{page 469 note 2} Briggs, U. S. Dept. of Agric. Bureau of Soils, Bulletin No. 10.

^{page 470 note 1} U.S. Bureau of Soils, Bulletin 50.

^{page 471 note 1} The addition of K to the left-hand side only means that the origin is moved a distance K in the negative direction of w.

^{page 472 note 1} This effect has been recognised by van Bommelen. See Die Absorption, p. 275.

^{page 472 note 2} Quoted in Preston's Heat, 2nd Edition, p. 357.