Note 573 — PRINCE RUPERT’S DROPS. LACRYMÆ VITREÆ.
William Johnston translation
It is not always necessary that the water should be cold; these drops will be formed also in warm water, as well as in every other fluid, and even in melted wax. See Redi’s experiments in Miscellan. Naturæ Curios. anni secundi, 1671, p. 426. They succeed best with green glass, yet I have in my possession some of white glass, which in friability are not inferior to those of green.