To the eye of science these ice-crystals are as precious as the diamond - as purely formed, as delicately built. Where no disturbing causes intervene, there is no disorder in this crystalline architecture. By their own constructive power molecule builds itself on to molecule with a precision far greater than that attainable by the hands of man.

Fragments of Science for Unscientific People, Chapter III (p. 83), D. Appleton & Co. 1875