CHAPTER XVII.
341. Since all bodies expand by heat and contract by cold, why does water, when it reaches the freezing point, expand?
Because, in freezing, water undergoes crystallization, in which its particles assume a new arrangement occupying greater space.
342. Why does water never freeze to a great depth?
Because the covering of ice which is formed upon the surface of the water prevents the cold air from continuing to draw off the caloric of the water.
"For he saith to the snow, Be thou on the earth; likewise to the small rain, and to the great rain of his strength."—Job xxxvii.
343. Why has this exceptional law of the expansion of water, when freezing, been ordained?