In a book written by his brother Thomas and devoted mainly to the medical purposes for which snow could be usefully employed, Erasmus Bartholinus added an Appendix on the form of snow crystals which he delineated with remarkable observation of detail in the illustration, Fig. 1, shown below. The appendix is entitled De Figura nivis Dissertatio. In the section Demonstratio figurae hexagonae favorum this reference to honeycombs (favorum) is clearly carried further in the section Nix figuram rotundam accipit primo, which is illustrated by his Fig. II.

The main point of interest of this work is its date, 1661. Robert Boyle’s Essay on Gems, 1672, has been claimed as “the first scientific contribution in the history of crystallography.” However, Robert Hooke’s Microgaphia, 1665 (Journal of Glaciology, Vol. 1, No. 10, 1951, p. 576), and the work cited above, both anticipate Boyle if they are accepted as scientific contributions to the subject.

Messrs. William H. Robinson Ltd. of Pall Mall, through whose courtesy we have been allowed to inspect this book, write in their catalogue “… the present tract is certainly scientific and is eleven years earlier than Boyle’s.” It goes on to say: “The author shows that snow assumes certain definite shapes … and speculates on the causes of the phenomenon. He quotes Descartes, Kepler and others. A few years later he became famous as the discoverer of the total refraction of iceland spar.”