part ii

. p. 511. [M. Boutigny’s beautiful experiment of making ice in a red-hot crucible is a striking phænomenon of this kind. It is thus performed:--A deep crucible of platinum is heated to a glowing red heat; liquid sulphurous acid, which has been preserved in the fluid state by a freezing mixture, and some water are then at the same instant poured into the crucible. The rapid evaporation of the volatile sulphurous acid, which boils below the freezing-point of water, produces such an intense degree of cold as to freeze the water, which is then thrown out of the crucible as a solid lump.]

[389] Philosoph. Transact. vol. lxxi.