Iacobus Leodiensis [Iacobus de Montibus, Iacobus de Oudenaerde]

Introit (ii)

(from Lat. introitus).

Vocal polyphonic introits are not very common, but there are English examples from the Middle Ages, for example in the Worcester Fragments (ed. in MSD, ii (1957), nos.9, 64, both troped settings of Salve sancta parens). There are 15th-century settings from the Continent, for example in plenary masses such as Du Fay's Missa Sancti Jacobi and in the Trent codices, which include a lengthy cycle of Propers (I-TRmn MS 88, 113v–220r, with some interruptions, a total of 14 cycles). It is almost always present in requiem masses, frequently being joined to the Kyrie in post-Renaissance examples (e.g. Mozart, Verdi).

The instrumental introit replaces all or part of the sung liturgical introit of the Mass. Usually the plainchant of the antiphon was set in full as an organ piece, leaving the psalm verse and the doxology to be sung in plainchant. It is not clear whether the organ piece was meant to replace only one performance of the antiphon or two or three. There are three such settings in the Buxheimer Orgelbuch (see Sources of keyboard music to 1660, §2(iii)), all for Marian votive masses. From the 16th century there are a number of examples in Hans Buchner's Fundamentum and in the tablature of Jan z Lublina; a Warsaw manuscript of about 1580, now surviving only in a photographic copy, contained no fewer than 47. The form was little cultivated in France and Italy, and only one English example has survived. This piece (EECM, x, 20) is part of Thomas Preston's Easter Sunday Mass. The antiphon Resurrexi is first set in two parts with the plainchant heavily ornamented in the bass. The organ then answers the singers with the second half of the following psalm verse in a three-part setting with the plainchant in the middle. The Sarum rite at that point required the repetition of the antiphon before the doxology; both were probably intended to be sung in plainchant. A four-part setting of the antiphon concludes the piece.

Introit plainchants have only rarely been set since the 16th century. In Frescobaldi's Fiori musicali (1635) short introductory toccatas take the place of the introit. In the High Mass of the 17th and 18th centuries the introit, spoken by the priest, was often covered entirely by an elaborate (vocal) setting of the Kyrie. It re-emerged as an instrumental form, however, with the development of organ accompaniments to Low Mass, for which Liszt and Kodály provided short movements. The typical French ‘organ mass’ suites of Tournemire and others always begin with an introductory movement for the entry of the ministers, a distinguished example being that in Messiaen's Messe de la Pentecôte (1949–50). See also Organ mass.

BIBLIOGRAPHY

ApelG

HarrisonMMB

C. Päsler: ‘Fundamentbuch von Hans von Constanz’, VMw, v (1889), 1–192

E. Southern: The Buxheim Organ Book (Brooklyn, NY, 1963)

H.R. Zöbeley: Die Musik des Buxheimer Orgelbuchs: Spielvorgang, Niederschrift, Herkunft, Faktur (Tutzing, 1964)

J. Caldwell: English Keyboard Music before the Nineteenth Century (Oxford, 1973/R)

JOHN CALDWELL

Intromessa.

See Intermedio.

Inuit music.

See Amerindian music, §II, 1(ix) and United States of America, §II, 4(ii).

Invention.

Usually a short vocal or instrumental piece with no very special defining characteristics apart from novelty of material or form. The concept of inventio (Lat.) or inventione (It.), initially through the influence of writers on rhetoric, is not infrequently met with in musical treatises of the Renaissance, where it may refer either to the ‘discovery’ of music as such (Tinctoris, De inventione et usu musicae) or to the processes of its composition. An early example of its use for a collection of works is Janequin's Premier livre des inventions musicales … contenant La Guerre … (1555). Italian examples are found in Cesare Negri's Nuove inventioni di balli (1604), Biagio Marini's Sonate, symphonie … con altre curiose e moderne inventioni (1629) and in many later works, including Bonporti's Invenzioni da camera for violin and continuo (1712), which were copied by Bach (whose own inventions, however, owe nothing to them formally). It is sometimes used merely as an abstract noun (Vivaldi: Il Cimento dell'armonia e dell'invenzione, 1725) and sometimes as a collective noun (Viadana: Cento concerti ecclesiastici … nova inventione commoda per ogni sorte de cantori, e per gli organisti, 1602). The earliest English example, for a specific piece, seems to be Dowland's ‘Invention … for two to playe upon one Lute’ (First Booke of Songs or Ayres, 1597). The German word is ‘Invention’, but German composers often preferred the Latin form ‘inventio’, as in the preface to Kuhnau's Frische Clavier-Früchte (1696).

The word has obvious affinities with ‘ricercare’, with its connotation of ‘seeking out’ or ‘finding’, and it has been pointed out that certain textless ricercares of the 16th and 17th centuries, intended for practice in singing, may well be considered, in a sense, ancestors of Bach’s inventions. Bach also preferred the Latin form, applying it ultimately to the 15 pieces in two-part counterpoint which he had originally called ‘preambulum’ in the Clavier-Büchlein vor W.F. Bach (1720). Two other autograph copies (one dated 1723) are known; in these the usual title is found. In addition there are found in all three manuscripts the 15 works in three-part counterpoint, originally called ‘fantasia’ and subsequently ‘sinfonia’. It is convenient to consider these at the same time, since they are frequently referred to colloquially as inventions, together with a number of other keyboard works in two-part counterpoint, including the four duettos from the Clavier-Übung, part iii.

The title-page of the 1723 manuscript reads in translation:

Straightforward instruction, whereby lovers of the keyboard, and especially those eager to learn, are shown a clear method, not only (1) of learning to play distinctly in two parts, but also, after further progress, (2) of managing three obbligato parts correctly and satisfactorily; and in addition not only of arriving at good original ideas [Inventiones] but also of developing them satisfactorily; and most of all of acquiring a cantabile style of playing while at the same time receiving a strong foretaste of composition.

Thus the works serve the dual purpose of providing technical practice and demonstrating the composer’s art. The title ‘inventio’ may well stem from Bach's use of this word in his preface to denote ‘original ideas’.

The key sequence of the 15 works in both sets is identical: C, c, D, d, E, E, e, F, f, G, g, A, a, B, b. There were lacking in this ascending order only another nine keys to arrive at the full set of 24 used in Das wohltemperirte Clavier, a scheme on which Bach was engaged at the same time.

The first four inventions and the eighth begin with imitation at the octave below; no.10 begins with imitation at the 11th below, while all the others begin with both parts simultaneously. Only no.6 is in two repeated sections, but Bach made nos.8 and 10 fall particularly clearly into two halves by repeating their opening imitative passages in inversion in the dominant key. Double counterpoint is used extensively, but always unobtrusively and without pedantry. From all this it can be seen that there is no one ‘invention form’ for Bach and that the title has been applied to these little masterpieces quite casually.

The sinfonias are predominantly fugal, though in no case does a single part enter with the subject alone. Nevertheless nos.1, 3, 4 and 7–14 all begin with subject, answer and subject in the manner of a fugal exposition. No.6 differs only in that its second and third entries are both in the dominant, while in nos.2 and 15 there are only two entries, both in the tonic. No.5 is exceptional in that the imitation is confined to the upper two parts throughout over an ostinato bass. Most of them employ a certain amount of triple counterpoint, but the device is used extensively only in no.3, where the subject and two countersubjects are used in all six of their possible inversions, and in no.9, where four of the possible combinations are employed for the three themes.

The four duettos from part iii of the Clavier-Übung are much longer pieces with either fugal or concertante implications or both. The first, in E minor, which is in double counterpoint, has strong affinities with the Courante from the sixth Partita. The second, in F, is a da capo movement which is also a fugue, and no.4, in A minor, is a fugue too. A number of movements from the partitas are in two-part counterpoint, of which the Fantasia in no.3 is in ritornello form, though it is treated with a good deal of freedom. Finally, in the E minor fugue from book 1 of Das wohltemperirte Clavier there is a solitary example of a two-part fugue.

The term ‘invention’ has occasionally been revived in modern times, either to denote a composition in two-part counterpoint or in a more general sense (e.g. Blacher, Zwei Inventionen für Orchester, op.46). The most interesting examples are the ‘inventions’ (not so called in the score but sanctioned by Reich) in the third act of Berg's Wozzeck: on a theme (i.e. a theme, variations and fugue, bars 3–70), a note (bars 71–121), a rhythm (bars 122–218), a chord (bars 220–319), a key (bars 320–71) and an ostinato movement in quavers (bars 372–92).

BIBLIOGRAPHY

A. Schering: ‘Geschichtliches zur “ars inveniendi” in der Musik’, JbMP 1925, 25–34

W. Reich: Alban Berg: Leben und Werk (Vienna, 1937, 3/1985)

H.-P. Komorowski: Die ‘Invention’ in der Musik des 20. Jahrhunderts (Regensburg, 1971)

W. Arlt: ‘Zur Handhabung der “inventio” in der deutschen Musiklehre des frühen achtzehnten Jahrhunderts’, New Mattheson Studies, ed. G.J. Buelow and H.J. Marx (Cambridge, 1983), 371–91

R. Woodley: ‘The Printing and Scope of Tinctoris's Fragmentary Treatise De inuentione et usu musice’, EMH, v (1985), 239–68

JOHN CALDWELL