In the very valuable _Lectures on the Science of Language_ by Professor F. Max Mueller, the second Lecture, which deserves careful study, is chiefly occupied by some account of the processes which he names respectively "phonetic decay" and "dialectic regeneration"; processes to which all languages have always been and ever will be subject. By "phonetic decay" is meant that insidious and gradual alteration in the sounds of spoken words which, though it cannot be prevented, at last so corrupts a word that it becomes almost or wholly unmeaning. Such a word as _twenty_ does not suggest its origin. Many might perhaps guess, from their observation of such numbers as _thirty, forty_, etc., that the suffix _-ty_ may have something to do with _ten_, of the original of which it is in fact an extremely reduced form; but it is less obvious that _twen-_ is a shortened form of _twain_. And perhaps none but scholars of Teutonic languages are aware that _twain_ was once of the masculine gender only, while _two_ was so restricted that it could only be applied to things that were feminine or neuter. As a somewhat hackneyed example of phonetic decay, we may take the case of the Latin _mea domina_, i.e. my mistress, which became in French _ma dame_, and in English _madam_; and the last of these has been further shortened to _mam_, and even to _'m_, as in the phrase "Yes, 'm." This shows how nine letters may be reduced to one. Similarly, our monosyllable _alms_ is all that is left of the Greek _ele{-e}mosyn{-e}_. Ten letters have here been reduced to four. This irresistible tendency to indistinctness and loss is not, however, wholly bad; for it has at the same time largely contributed, especially in English, to such a simplification of grammatical inflexions as certainly has the practical convenience of giving us less to learn. But in addition to this decay in the forms of words, we have also to reckon with a depreciation or weakening of the ideas they express. Many words become so hackneyed as to be no longer impressive. As late as in 1820, Keats could say, in stanza 6 of his poem of _Isabella_, that "His heart beat awfully against his side"; but at the present day the word _awfully_ is suggestive of schoolboys' slang. It is here that we may well have the benefit of the principle of "dialectic regeneration." We shall often do well to borrow from our dialects many terms that are still fresh and racy, and instinct with a full significance. Tennyson was well aware of this, and not only wrote several poems wholly in the Lincolnshire dialect, but introduced dialect words elsewhere. Thus in _The Voyage of Maeldune_, he has the striking line: "Our voices were thinner and fainter than any flittermouse-shriek." In at least sixteen dialects a _flittermouse_ means "a bat."