lv. (an 1842), 472.
Journal de Physique, xxvi. (an 1785), 34.
In looking through some early volumes of the Philosophical Transactions, I found an 'Extract of a letter written by Mr. Muraltus of Zurich (September 1668), concerning the Icy and Chrystallin Mountains of Helvetia, called the Gletscher, English'd out of Latin' (Phil. Trans. iv. 982), which at first looked something like an assertion of the prismatic structure of ice on a large scale. The English version is as follows:—'The snow melted by the heat of the summer, other snow being faln within a little while after, and hardened into ice, which by little and little in a long tract of time depurating itself turns into a stone, not yielding in hardness and clearness to chrystall. Such stones closely joyned and compacted together compose a whole mountain, and that a very firm one; though in summer-time the country-people have observed it to burst asunder with great cracking, thunder-like.'
See the woodcut illustrating Professor Tyndall's remarks in the 148th volume of the Philosophical Transactions (1858, p. 214).
Bischof, Physical Researches, 189.