30 So Werner remarked that Michael Angelo and Bramanti could not have built of gypsum at Paris on the scale they built of travertin in Rome.
31 Sir G. Greenhill, Determination of the greatest height to which a Tree of given proportions can grow, Cambr. Phil. Soc. Pr. IV, p. 65, 1881, and Chree, ibid. VII, 1892. Cf. Poynting and Thomsonãs Properties of Matter, 1907, p 99.
32 In like manner the wheat-straw bends over under the weight of the loaded ear, and the tip of the catãs tail bends over when held upright,ãnot because they ãpossess flexibility,ã but because they outstrip the dimensions within which stable equiôÙlibôÙrium is possible in a vertical position. The kittenãs tail, on the other hand, stands up spiky and straight.
33 Modern Painters.
34 The stem of the giant bamboo may attain a height of 60 metres, while not more than about 40 cm. in diameter near its base, which dimensions are not very far short of the theoretical limits (A. J. Ewart, Phil. Trans. vol. 198, p. 71, 1906).