Page:EB1911 - Volume 20.djvu/302

 Earl Elwin gave money “triginta libras” to the monastery at Ramsay for copper pipes for a great pneumatic organ to be played on high days and holidays.

The great activity recorded in the 12th and 13th centuries in Germany is probably due to the influence and teaching of Byzantine masters during the 9th century. Pope John VIII. (872–880) applied to Bishop Anno of Freising to send him an organ and an organist. Organs were installed in Cologne (10th century), in Halberstadt, in Erfurt, in Augsburg, Weltenburg (11th century); in Utrecht, Constance, Petershausen (12th century); Petersberg, Cologne Cathedral, 13th century. The rest of the literary and archaeological material—treatises, monuments, miniatures—available during the later middle ages yields very scant authenticated information as to the progressive steps which lie between the 12th-century organ as described by Theophilus and the large church organs of the days of Praetorius (1618).

The keyboard is the principal feature concerning which miniatures offer any evidence. Here and there a 13th-century miniature gives a hint of balanced keys on small portative organs which already abound during that and the next century. The Bernese monk in his treatise on the organ to which reference was made in the note above, clearly describes balanced keys, depressa lamina, pressed down, not pulled out, as were those mentioned by Theophilus; his description conforms strictly with that of Hero, which suggests that he was borrowing from classical authorities rather than describing an actual instrument with which he was well acquainted, an expedient to which

many medieval writers had recourse. In the 14th-century miniatures, balanced keys are general for the larger portable organs. The adoption of narrower keys in the larger organs may no doubt be traced to the influence of the portatives, in which they in most cases resemble the white keys of the modern pianoforte. There is no miniature on record in which the fist action on the keys is indicated, the performer during the 10th, 11th and 12th centuries being depicted in the act of drawing out the stop-like sliders—as for instance, in the 12th-century manuscript Bible of St Etienne Harding at Dijon (fig. 6), where the organist is playing the notes D and F, the sliders being lettered from C to C. From the 13th century the keys are shown pressed down by means of one finger or of finger and thumb (fig. 7). In the beautiful Spanish MS. said to have been compiled for Alphonso XII. (c. 1237), known as the Cantigas de Santa Maria, a portative is shown having balanced keys, one of which is being lightly pressed by the thumb, the instrument resting on the palm—while the left hand manipulates the bellows.

The keys themselves varied in shape, being either like a T; a wide rectangle, with or without the corners rounded off, or a narrow rectangle. The earliest instance of chromatic keyboard is that of the organ at Halberstadt built in 1361 and restored in 1495. An inscription on the keyboard states that it formed part of the original organ, which had the semitonal arrangement of keys.

It must not, however, be inferred from these isolated cases that balanced keys were general from the 13th century, nor that the chromatic keys were common in the 14th. The St Cecilia in the altarpiece in Ghent by the brothers Hubert and Jan van Eyck (15th cent.) is represented as playing upon an organ with a modern-looking keyboard.

A picture by Fra Angelico (15th cent.) in the National Gallery shows a portative with accidentals. It will probably be found that the earliest development of the organ took place in Germany and in the Netherlands.

ORGANISTRUM, the medieval Latin name for the earliest known form of the (q.v.). The organistrum was large enough to rest on the knees of two performers sitting side by side, one of whom turned the crank setting the wheel in motion, while the other, the artist, manipulated the keys. The word organistrum is derived from organum and instrumentum; the former term was applied to the primitive harmonies, consisting of octaves accompanied by fourths or fifths, first practised by Hucbald in the 10th century. This explanation enables us to fix with tolerable certainty the date of the invention of the organistrum, at the end of the 10th or beginning of the 11th century, and also to understand the construction of the instrument. A stringed instrument of the period—such as a guitar-fiddle, a rotta or oval vielle—being used as model, the proportions were increased for the convenience of holding the instrument and of dividing the performance between two persons. Inside the body was the wheel, having a tire of leather well rosined, and working easily through an aperture in the sound-board. The three strings resting on the wheel and supported besides on a bridge of the same height all sounded at once as the wheel revolved, and in the earliest examples the wooden tangents taking the place of fingers on the frets of the neck acted upon all three strings at once, thus producing the harmony known as organum.

