Page:The fairy tales of science.djvu/55

Rh word which we make use of to denote the extrication of light and heat during combustion, and the ancient notion that it is one of the primordial constituents of the material world is no longer tenable.

Fire is often spoken of as the destroying element, but we must bear in mind that combustion only alters the state of bodies; there is no actual destruction or loss of weight when a body is burned, though the products of combustion may be invisible.

If we set fire to a small fragment of phosphorus and cover it with a dry tumbler, dense white fumes will arise, which will condense on the sides of the glass in snow-like flakes. If we collect this white substance and weigh it, we shall find that it is more than twice as heavy as the phosphorus. How is this? The explanation of this apparent anomaly is simple enough. The phosphorus, in burning, combines with the oxygen of the atmosphere to form this white compound, which is known to chemists by the name of Phosphoric Acid, the weight of the oxygen is therefore added to that of the phosphorus.

Some of our readers will doubtless receive this information with astonishment. It seems scarcely credible that a substance having the appearance of snow should be produced by the union of an invisible gas and a yellow wax-like solid. Chemistry is a science of marvels, and this wonderful