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Moreover, freezing, which is the most extreme and violent effect of cold in bodies, is a condition of water, but a function of air. For water of itself is fluid, uncongealed and not cohesive; but when it is compressed by air because of its cold state, it becomes taut and compact. This is the reason for the sayingIncluded without authority among Callimachus’s fragments (787 = anon. 384) by Schneider, but rejected by Pfeiffer. If Southwind challenges North, instantly snow will appear. For after the Southwind has collected the moisture as raw material, the Boreal air takes over and congeals it. This is particularly evident in snowfields: when they have discharged a preliminary exhalation of air that is thin and cold, they melt.Cf. Mor. 691 f and Hubert’s references ad loc. AristotleFrag. 212, ed. Rose and cf. Mor. 695 d. also declares that whetstones of lead will melt and become fluid in the wintertime through excess of cold when no water is anywhere near them; it seems probable that the air with its coldness forces the bodies together until it crushes and breaks them.There is here probably a confusion of lead and tin, for both of which the term stannum is used in Latin. Tin is reduced to powder by severe cold, owing to transformation to its allotrope. In [Aristotle], De Mir. Ausc. 50 (p. 257, L.C.L.) the more nearly correct statement appears that tin melts in severe cold. This note is due to the suggestion of O. T. Benfey of Haverford College.
