stances; first to the elements, which are to be arranged; secondly to the accidents, by which these elements are distinguished; and thirdly to the law of succession, by which the arrangement is effected.

In making verse, the elements subjected to the rhythm, may be either syllables, or verses, or staves. The only accidents, which need be noticed as of rhythmical value, are three, the time or quantity, the accent, and the modification of the sound.

Rhythm may be marked either by the time or the accent. In the great family of languages which has been termed the Indo-European, and which spread from the Ganges to the Shannon, three made time the index of their rhythm, to wit the Sanscrit, Greek, and Latin; all the the others adopted accent. It is remarkable that those dialects which now represent the Sanscrit, Greek, and Latin, have lost their temporal and possess merely an accentual rhythm. We are able in some measure to follow the progress of this change. So gradual was it in the Greek, that even as late as the eleventh century there were authors who wrote indifferently in either rhythm. The origin, however, of accentual verse, as it now prevails in those languages, is by no means clear. Whether it were borrowed from the northern invader, or were the natural growth of a mixed and broken language, or merely the revival of a vulgar rhythm, which had been heretofore kept under by the prevalence of one more fashionable and perhaps more perfect, are questions I shall pass by, as being at least as difficult as they are interesting.

ARRANGEMENT OF THE SUBJECT.

Having premised thus much as to the meaning of our terms, I will now lay before the reader the course I shall follow in tracing the progress of our English rhythms. In the second book we shall consider the rhythm of indivi dual verses; and in the third the rhythm of particular pas

sages, or, to speak more precisely, the flow of several verses in combination; while the fourth book will be devoted to the history of our staves, that is, of those regular combinations, which form as it were a second class of elements to be regulated by the rhythm.

The book which opens with the present chapter is little more than introductory, but the matters discussed in it are of high importance to the right understanding of the subject. In the next chapter we shall consider the different modifications of sound, with a view to the aid they afford us in embellishing and perfecting the rhythm. In the third we shall inquire what constitutes a syllable, and discuss the nature of accent in the fourth, and of quantity in the fifth. The various kinds of rhime will be the subject of the sixth chapter, and in the seventh and last we shall treat of the rhythmical pauses.

CHAPTER II.

THE VOICE.

If we drop a small heavy body into still water it forms a circular wave, which gradually enlarges and loses itself upon the surface. In like manner, if one hard body strike against another-as the cog of a metal wheel against a quill-a wave is formed in the air which expands on all sides round the point of contact. When this wave reaches the ear, it produces on that organ the sensation of sound.

If now the wheel be turned round, so that the cogs strike against the quill in succession, several concentric waves are produced, following each other at equidistant periods of time; and if the velocity be such that there are more than thirty sound-waves in a second, the sensation produced by one lasts till another enters the ear, and a continuous sound is the result. This continuous sound is called a tone or musical note.

As we increase the number of sound-waves, the tone changes its character, and is said to become sharper. When more than six thousand enter the ear in a second, the tone becomes so sharp and squeaking as to be no longer perceptible by organs constituted like our own.

The wave which thus produces the sensation of sound, differs widely in origin from that which moves along the surface of the water. The latter is formed by the vertical rising of the watery particles, and as these fall again in obedience to the force of gravity, they drive upwards those next adjoining. The motion of the particles is thus perpendicular or nearly so to the direction of the wave's motion. The air-wave is formed by the condensation as

well as by the displacing of the particles, and the moving power in this case is elasticity. The airy particles are driven on a heap, till the force of elasticity becomes greater than the impelling force, and they are driven back to their former station. The neighbouring particles are then similarly acted on, and a slight motion or vibration in the same line of direction as that in which the soundwave is travelling, takes place in all the particles. On the size of this vibration depends the loudness of the sound.

The tones of the human voice are produced by the vibrations of two membranes, which have been called the vocal ligaments. These are set in motion by a stream of air gushing from the lungs, and we can at pleasure regulate the sharpness and the loudness of the sound produced. The mechanism, by which this is effected, has been lately made the subject of some very interesting speculations.*

If two elastic membranes stretched upon frames so as to leave one edge free, be placed opposite to each other, with the free edges uppermost, and a current of air pass between them from beneath, they will be differently affected according to their inclination towards each other. If they incline from each other, they will bulge inwards, if towards each other, they will bulge outwards, if they be parallel, they will vibrate. Now the wind-pipe is contracted near the mouth by a projecting mass of muscles called the Glottis. The edges of the Glottis are membranes, and form the vocal ligaments. Ordinarily these membranous edges are inclined from each other, and consequently no vibrations take place during the passage of the breath; but by the aid of certain muscles, we can place them parallel to each other, when they immediately vibrate and produce a tone. With the aid of other muscles, we can increase their tension, and thereby the sharpness of the tone, and by driving the air more forcibly from the lungs, we may increase its loudness. The tone thus

* See Mr. Willis's papers in the Cambridge Philosophical Transactions.

formed is modified by the cavities of the throat, nose, and mouth, These modifications form the first elements of articulate language, or the letters.

VOCAL LETTERS.

It has been shown that the note of a common organ reed may take the qualities of all the vowel-sounds in succession. This is effected by merely lengthening the tube, which confines the vibrations. It would seem, therefore, that the peculiar characters of the different vowels depend entirely on the length of the cavity, which modifies

the voice.

In pronouncing the long a in father, the cavity seems barely, if at all, extended beyond the throat; in pronouncing the au of aught, it reaches to the root of the tongue, and to the middle of the palate in pronouncing the long e of eat; the sound of the long o in oat, requires the cavity to be extended to the lips, which must be stretched out to form a cavity long enough to pronounce the u in jute.

Every addition to the length of the tube or cavity, affects in a greater or less degree the character of the tone. The possible number of vowel-sounds therefore, can have no limit; but as there are rarely more than seven or eight in any one language, we may conclude that the human ear is not readily sensible to the nicer distinctions.

In pronouncing the vowels a and e, as they sound in ale and eel, we narrow the cavity by raising the tongue towards the palate, while in pronouncing a, au, o, as they sound in father, aught, oat, the cavity is broad and open. These two sets of vowels have accordingly been distinguished as the narrow and the broad vowels.

Next to the vowels, the letters which have spread most widely, are the three,

b, d, g.

* By Mr. Willis.