variety and relief in the way of accompaniment. The so-called Gregorian chants being originally written without harmony—at any rate in the modern acceptation of the term—the accompanyist is left at liberty to supply such as his taste and musical resources suggest. The English chants, on the other hand, were written with vocal harmony from the first; and to them much agreeable change can be imparted either by altering the position of the harmonies, or by forming fresh melodic figures on the original harmonic progressions. When sung in unison, as is now not unfrequently the case, wholly fresh harmonies can be supplied to the English chants, as in the case of the Gregorian. Treated in this manner they are as susceptible of great variety and agreeable contrast as are the older chants.
In accompanying English psalm tunes it is usual to make use of somewhat fuller harmony than that which is represented by the four written voice-parts. The rules of musical composition, as well as one's own musical instinct, frequently require that certain notes, when combined with others in a particular manner, should be followed by others in certain fixed progressions; and these progressions, so natural and good in themselves, occasionally lead to a succeeding chord or chords being presented in 'incomplete harmony' in the four vocal parts. In such cases it is the custom for the accompanyist to supply the omitted elements of the harmony; a process known by the term 'filling in.' Mendelssohn's Organ Sonatas, Nos. 5 and 6, each of which opens with a chorale, afford good examples of how the usual parts may be supplemented with advantage. The incomplete harmonies are to be met with most frequently in the last one or two chords of the clauses of a tune; the omitted note being generally the interval of a fifth above the bass note of the last chord; which harmony note, as essential to its correct introduction, sometimes requires the octave to the preceding bass note to be introduced, as at the end of the third clause of the example below; or to be retained if already present, as at the end of the fourth clause. An accompaniment which is to direct and sustain the voices of a congregation should be marked and decided in character, without being disjointed or broken. This combination of distinctness with continuity is greatly influenced by the manner in which the repetition notes are treated. Repetition notes appear with greater or less frequency in one or other of the vocal parts of nearly all psalm tunes, as exhibited in the example below. Those that occur in the melody should not be combined, but on the contrary should generally speaking be repeated with great distinctness. As such notes present no melodic movement, but only rhythmic progress, congregations have on that account a tendency to wait to hear the step from a note to its iteration announced before they proceed; so that if the repetition note be not clearly defined, hesitation among the voices is apt to arise, and the strict time is lost. The following example will sound very tame and undecided if all the repetition notes at the commencement of the first and second clauses be held on.
A very little will suffice to steady and connect the organ tone; a single note frequently being sufficient for the purpose, and that even in an inner part, as indicated by the binds in the following example. A repetition note in the bass part may freely be iterated on the pedal, particularly if there should be a tendency among the voices to drag or proceed with indecision.
Old Hundredth tune.
The important subject of additional accompaniments to works already possessing orchestral parts, with the view of supplying the want of an organ, or obtaining the increased effects of the modern orchestra, is treated under the head of Additional Accompaniments.
[ E. J. H. ]
ACCORDION (Ger. Handharmonika, also Ziehharmonika). A portable instrument of the free-reed species, invented at Vienna by Damian, in the year 1829. It consists of a small pair of hand-bellows, to one side of which is affixed a key-board, containing, according to the size of the instrument, from five to fifty keys. These keys open valves admitting the wind to metal reeds, the latter being so arranged that each key sounds two notes, the one in expanding, the other in compressing the bellows. The right hand is placed over the key-board, while the left works the bellows, on the lower side of which are usually to be found two keys which admit wind to other reeds furnishing a simple harmony—mostly the chords of the tonic and dominant. It will be seen that the capabilities of the instrument are extremely limited, as it can only be played in one key, and even in that one imperfectly; it is, in fact, but little more than a toy. It was originally an extension of the 'mouth-harmonica'—a toy constructed on a similar principle, in which the reeds were set in vibration by blowing through holes with the mouth, instead of by a key-board. This latter instrument is also known as the Æolina.
[ E. P. ]