[363] Cf. some of J. H. Vincent’s photographs of ripples, in Phil. Mag. 1897–1899; or those of F. R. Watson, in Phys. Review, 1897, 1901, 1916. The appearance will depend on the rate of the wave, and in turn on the surface-tension; with a low tension one would probably see only a moving “jabble.” FitzGerald thought diatom-patterns might be due to electromagnetic vibrations (Works, p. 503, 1902).

[364] Cushman, J. A. and Henderson, W. P., Amer. Nat. XL, pp. 797–802, 1906.

[365] This does not merely neglect the broken ones but all whose centres lie between this circle and a hexagon inscribed in it.

[366] For more detailed calculations see a paper by “H.M.” [? H. Munro], in Q. J. M. S. VI, p. 83, 1858.

[367] Cf. Hartog, The Dual Force of the Dividing Cell, Science Progress (n.s.), I, Oct. 1907, and other papers. Also Baltzer, Ueber mehrpolige Mitosen bei Seeigeleiern, Inaug. Diss. 1908.

[368] Observations sur les Abeilles, Mém. Acad. Sc. Paris, 1712, p. 299.

[369] As explained by Leslie Ellis, in his essay “On the Form of Bees’ Cells,” in Mathematical and other Writings, 1853, p. 353; cf. O. Terquem, Nouv. Ann. Math. 1856, p. 178.

[370] Phil. Trans. XLII, 1743, pp. 565–571.

[371] Mém. de l’Acad. de Berlin, 1781.

[372] Cf. Gregory, Examples, p. 106, Wood’s Homes without Hands, 1865, p. 428, Mach, Science of Mechanics, 1902, p. 453, etc., etc.