The sun and the moon received their names for good reasons; the former because it is the creator (light and heat being the causes of inorganic life), and the latter because it was the first measurer of time; and these names they have borne for at least four thousand years—we do not know how much longer. But now those words have become mere names; mere sounds which are the vocal indications of the objects to which they are applied, so that if by some wizardry we were all, with one exception, to wake up to-morrow calling the light which rules the day, moon, and that which rules the night, sun, we should be perfectly satisfied, and find in it no inconvenience; and moreover we should look upon him who used the words in the converse senses, that we had forgotten, as a madman. Words however have, with very few exceptions, a real meaning, or at least a reason for their use, as _sun_ and _moon_ have. The words without such meaning may be all told upon the fingers. Two words of scientific origin, but very common use, are illustrative examples—_chloroform_ and _gas_, both of which are of recent, the former of very recent, fabrication. Chloroform is so called because it is, or is supposed to be, a chloride of formyl, which is the base of formic acid, a fluid found in red ants; _formica_ being the Latin for ant. It was desirable to have a convenient name for this substance, and the name was made by uniting the first syllable of _chloride_, or _chlorine_, with the first syllable of _formyl_; whence we have _chloro-form_. The name _gas_ was invented, we know not why or wherefore, by a Dutch chemist, some two hundred and fifty years ago, for all those compressible, air-like fluids to which it is now applied. It was convenient and came first into scientific and then into general use, so that now it is one of the commonest words, even in a sarcastic, metaphorical sense, in the speech of all civilized peoples. Now nearly all words have a significant origin, like _chloroform_. Those which are without inherent significance, like gas, are very few indeed. Words like these, and like _oxygen_ (which is only about one hundred and fifty years old, and means acid-maker), are called coined words, because they were recently and deliberately made. The words which form the bulk of language are of very remote origin, and, until lately, of untraced growth.