The last and most curious experiment performed by professor Boutigny, was the freezing of water in a red-hot vessel. Having heated a platinum cup red-hot, he poured into it a small quantity of water, which was kept in a globular form, as in the other experiments. He then poured into the cup some liquid sulphurous acid; when a sudden evaporation ensued, and, on quickly inverting the cup, there came out a small mass of ice. The principle of this experiment, which called forth loud and continued applause, is this:--sulphurous acid has the property of boiling water when it is at a temperature below the freezing point; and, when poured into the heated vessel, the suddenness of the evaporation occasions a degree of cold sufficient to freeze water. Liquid carbonic acid takes a high position for its freezing qualities. Mr. Adams, of Kensington, manufactures this curious liquid as an article of commerce, and has, occasionally, as much as nine gallons of it in store. In drawing it from its powerful reservoirs, it evaporates so rapidly as to freeze, and it is then a light porous mass, like snow. If a small quantity of this is drenched with ether, the degree of cold produced is even more intolerable to the touch than boiling water; a drop or two of the mixture producing blisters, just as if the skin had been burned! Mr. Adams states that, in eight minutes he has frozen a mass of mercury weighing ten pounds. In one department of knowledge--that of vapours and gases--on which chemistry casts so much light, we discover many remarkable phenomena. Few persons have resided, for example, in the fenny and swampy districts of our island, without seeing, at least occasionally, the ignis fatuus, Will-o’-the-wisp, or Jack-o’-lantern, hovering a few feet above the surface of stagnant water. “Wild fires dancing o’er the heath,” may be observed, indeed, at almost all times of the year, but it is chiefly in autumn, and particularly in November, that they flit in mazy circles and irregular evolutions; sometimes at the edge of a morass, over the tops of withered sedges, reeds, and brushwood; and, at others, over palings and hedgerows, or the still surface of the oozy bog. It has been argued by some, that they are effects produced by luminous insects, as the glow-worm, the gnat, and the mole-cricket. But this theory is very unsatisfactory, and the cause which is now generally acknowledged to be the real one, is far more natural. There is a substance readily obtained, but of very offensive odour, called phosphoret of lime; and, if a piece of this be taken and dropped into a pool of water, little flames will be seen on its surface. These arise from the power of the substance to decompose water, in consequence of which, the hydrogen ascends to the surface, and ignites on coming in contact with the air.