Chapter III: THE SOUTHERN ZONE.--Characterized by absence of Cyprinidae and (9)

It is towards the close of the 12th century and in the beginning of the 13th century that the character of illumination settles down on more conventional lines. Hitherto gold had been applied in a liquid state; now it is laid on in leaf and is highly burnished, a process which lends a brilliant effect to initial and miniature. A great change passes over the face of things. The large, bold style gives place to the minute. Volumes decrease in size; the texts are written in close-packed characters; the large and simple is superseded by the small and decorated. The period has arrived when book ornamentation becomes more settled and accurately defined within limits, and starts on the course of regulated expansion which was to run for three hundred years down to the close of the 15th century. In the 13th century the historiated or miniature initial, that is, the initial letter containing within its limits a miniature illustrating the subject of the immediate text, is established as a favourite detail of ornamentation, in addition to the regular independent miniature. Such initials form a prominent feature in the pretty little Bibles which were produced in hundreds at this period. But a still more interesting subject for study is the development of the border which was to have such a luxuriant growth in the 13th, 14th and 15th centuries. Commencing as a pendant from the initial, with terminal in form of bud or cusp, it gradually pushes its way along the margins, unfolding foliage as it proceeds, and in course of time envelopes the entire page of text in a complete framework formulating in each country a national style.

In the miniatures of the 13th century the art of England, of France, and of the Low Countries runs very much in one channel. The Flemish art, however, may be generally distinguished from the others by the heavier outline already noticed. The French art is exquisitely exact and clean-cut, and in its best examples it is the perfection of neat-handedness. English art is perhaps less exact, but makes up for any deficiency in this direction by its gracefulness. However, there is often little to choose between the productions of the three countries, and they are hard to distinguish. As an aid for such distinction, among small differences, we may notice the copper tone of French gold contrasting with the purer metal in English MSS.; and the favour shown to deep ultramarine appears to mark French work. But, besides actual illuminated miniature painting, there is also a not inconsiderable amount of freehand illustrative drawing in the MSS. In this particular the English artist maintains the excellence of work which distinguished his ancestors. Such series of delicate drawings, slightly tinted, as those to be seen in the famous Queen Mary's Psalter (Royal MS. 2 B. vii.), and in other MSS. of the 13th and 14th centuries in the British Museum, are not surpassed by any similar drawings done at the same period in any other country. In the 13th century also comes into vogue the highly decorated diaper-work, generally of lozenges or chequered patterns in brilliant colours and brightly burnished gold. These fill the backgrounds of miniatures and initials, together with other forms of decoration, such as sheets of gold stippled or surface-drawn in various designs. Diapering continued to be practised in all three countries down into the 15th century; and in particular it is applied with exquisite effect in many of the highly-finished MSS. of the artists of Paris.

To return to the growth of the borders: these continue to be generally of one style in both England and France and in Flanders during the 13th century; but, when with the opening of the 14th century the conventional foliage begins to expand, a divergence ensues. In France and Flanders the three-pointed leaf, or ivy leaf, appears, which soon becomes fixed and flourishes as a typical detail of ornament in French illumination of the 14th and 15th centuries. In England there is less convention, and along with formal branches and leafage, natural growths, such as daisy-buds, acorns, oak leaves, nuts, &c., are also represented.

German.

Meanwhile German illumination, which in the large MSS. of the 12th century had given high promise, in the following centuries falls away and becomes detached from the western schools, and is, as a general rule, of inferior quality, although in the 13th century fine examples are still to be met with. Dark outlines and backgrounds of highly-burnished gold are in favour. At present, however, there is not sufficient published material to enable us to pass a definite judgment on the value of German illumination in the later middle ages. But the researches of scholars are beginning to localize particular styles in certain centres. For example, in Bohemia there was a school of illumination of a higher class, which seems later to have had an influence on English art, as will be noticed presently.

Italian.

We must now turn to Italy, which has been left on one side during our examination of the art of the more western countries. In attempting to bridge the gap which severs the later classical style of Rome from the medieval art of Italy, much must be left to conjecture. That a debased classical style of drawing was employed in the earlier centuries of the middle ages we cannot doubt. Such a MS. as the Ashburnham Genesis of the 7th century, which contains pictures of a somewhat rude character but based apparently upon a recollection of the classical drawing of earlier times, and which appears to be of Italian origin, serves as a link, however slight. Coming down to a later period, the primitive native art of the Frankish empire, as we have seen, extended into northern Italy under the name of Franco-Lombardic ornamentation; and we have also seen how the art of the Byzantine school reacted on the art of the southern portion of the country. Hence, in the middle ages, the ornamentation of Italian MSS. appears to move on two leading lines. The first, which we owe to the Byzantine influence, in which figure-drawing is the leading idea, follows the old classical method and, showing a distinctly Greek impress, leads to the style which we recognize as Italian _par excellence_, and which is seen most effectively manifested in the works of Cimabue and Giotto and of allied schools. In this style the colouring is generally opaque: the flesh tints being laid over a foundation of deep olive green, which imparts a swarthy complexion to the features--a practice also common in Byzantine art. The other line is that of the Lombardic style which, like the Celtic school of the British Isles, was an art almost exclusively of pure ornament, of intricate interlacings of arabesques and animal forms, with bright colouring and ample use of gold. The Lombardic style was employed in certain centres, as, for example, at Monte Cassino, where in the 11th, 12th and 13th centuries brilliant examples were produced. But it was not destined to stand before the other, stronger and inherently more artistic, style which was to become national. Still, its scheme of brighter colouring and of general ornament seems to have had an effect upon later productions, if we are not mistaken in recognizing something of its influence in such designs as the interlaced white vine-branch borders which are so conspicuous in Italian MSS. of the period of the Renaissance.

DURANDUS. DE DlVINIS OFFICIIS. FOURTEENTH CENTURY. Italian School.
(British Museum. Add. MS. 31,032.)]

VALERIUS MAXIMUS. ABOUT A.D. 1475. Executed for Philippe de Comines.
(British Museum. _Harley M.S._ 4374.)]

14th Century.

The progress of Italian illumination in the style influenced by the Byzantine element is of particular interest in the general history of art, on account of the rapidity with which it grew to maturity, and the splendour to which it attained in the 15th century. Of the earlier centuries the existing examples are not many. That Italian artists were capable of great things as far back as the 12th century is evident from their frescoes. We may notice the curious occurrence of two very masterly paintings, the death of the Virgin and the Virgin enthroned, drawn with remarkable breadth in the Italian style, in the _Winchester Psalter_ (Cottonian MS. Nero C. iv.) of the middle of that century, as a token of the possibilities of Italian illumination at that date; but generally there is little to show. Even at the beginning of the 14th century most of the specimens are of an ordinary character and betray a want of skill in striking contrast with the highly artistic productions of the Northern schools of England and France at the same period. But, though inferior artistically, Italian book ornamentation had by this time been so far influenced by the methods of those schools as to fall into line with them in the general system of decoration. The miniature, the initial, the miniature-initial and the border--all have their place and are subject to the same laws of development as in the other schools. But, once started, Italian illumination in the 14th century, especially in Florence, expanded with extraordinary energy. We may cite the Royal MS. 6, E. ix., containing an address to Robert of Anjou, king of Sicily, 1334-1342, and the Add. MS. 27,428 of legends of the saints, of about the year 1370, as instances of very fine miniature-work of the Florentine type. As the century advances, Italian illumination becomes more prolific and is extended to all classes of MSS., the large volumes of the Decretals and other law books, and still more the great folio choral books, in particular affording ample space for the artist to exercise his fancy. As was natural from the contiguity of the two countries, as well as from political causes, France and Italy influenced each other in the art. In many MSS. of the Florentine school the French influence is very marked, and on the other hand, Italian influence is exercised especially in MSS. of the southern provinces of France. Italian art of this period also in some degree affected the illumination of southern German MSS.

We have also to note the occurrence in Italy in the 14th century of good illustrative outline drawings, generally tinted in light colours, and occasionally we meet with a wonderfully bright style of illumination of a lighter cast of colouring than usually prevails in Italian art: such as may be seen in a MS. of Durandus _De divinis oficiis_ (Brit. Mus., Add. MS. 31,032) containing an exquisite series of initials and borders.

Taking a general view of the character of European illumination in the 14th century it may be described as an art of great invention and flexibility. The rigid exactness of the 13th century is replaced by flowing lines, just as the stiff, formal strokes of the handwriting of that century was exchanged for a more cursive and easy style. The art of each individual country now developed a national type of its own, which again branched off into the different styles of provincial schools. For example, in the eastern counties of England a very fine school of illumination, the East Anglian, was established in the first half of the century and produced a series of beautiful MSS., such as the _Arundel Psalter_ (No. 83) in the British Museum.

Distinctive Borders.

By the end of the century the borders had developed on national lines so fully as to become, more than any other detail in the general scheme, the readiest means of identifying the country of origin. First as to the English border: the favour shown to the introduction of natural growths among the conventional foliage thrown out from the frame into which the border had by this time expanded has already been noticed. But now a new feature is introduced. The frame up to this time had consisted generally of conventional branches with bosses at the corners. Now it is divided more into compartments within which twining coils of ornament resembling cut feather-work are common details; and feathery scrolls fill the corner-bosses and are attached to other parts of the frame; while the foliage thrown out into the margin takes the form of sprays of curious lobe- or spoon-shaped and lozenge-shaped leaves or flowers, with others resembling curled feathers, and with cup- and trumpet-shaped flowers. This new style of border is contemporaneous with the appearance of a remarkably brilliant style in the miniatures, good in drawing and rich in colouring; and an explanation for the change has been sought in foreign influence. It has been suggested, with some plausibility, that this influence comes from the school of Prague, through the marriage of Richard II. with Anne of Bohemia in 1382. However this may be, there certainly is a decidedly German sentiment in the feathery scrolls just described.

Turning to the French border, we find towards the close of the 14th century that the early ivy-leaf pendant has now invaded all the margins and that the page is set in a conventional frame throwing off on every side sprigs and waving scrolls of the conventional ivy foliage, often also accompanied with very delicate compact tracery of minute flower-work filling the background of the frame. Nothing can be more charming than the effect of such borders, in which the general design is under perfect control. The character, too, of the French miniature of this period harmonizes thoroughly with the brilliant border, composed as it is very largely of decorative elements, such as diapered patterns and details of burnished gold. In the Low Countries, as was natural, the influence of French art continued to have great weight, at least in the western provinces where the style of illumination followed the French lead.

The Italian border in its ordinary form was of independent character, although following the methods of the West. Thrown out from the initial, it first took the form of pendants of a peculiarly heavy conventional curling foliage, associated, as progress was made, with slender rods jointed at intervals with bud-like ornaments and extending along the margins; at length expanding into a frame. The employment of gilt spots or pellets to fill spaces in the pendants and borders becomes very marked as the century advances. They are at first in a simple form, but they gradually throw out rays, and in the latter shape they become the chief constituents of one kind of border of the 15th century.

15th Century.

Illumination in the 15th century enters on a new phase. The balance is no longer evenly maintained between the relative values of the miniature and the border as factors in the general scheme of decoration. The influence of a new sentiment in art makes itself felt more and more; the flat treatment of the miniature gradually gives place to true laws of perspective and of figure-drawing, and to the depth and atmospheric effects of modern painting. Miniature painting in the decoration of MSS. now became more of a trade; what in old times had been done in the cloister was now done in the shop; and the professional miniaturist, working for his own fame, took the place of the nameless monk who worked for the credit of his house. Henceforth the miniature occupies a more important place than ever in the illuminated MS.; while the border, with certain important exceptions, is apt to recede into an inferior position and to become rather an ornamental adjunct to set off the miniature than a work of art claiming equality with it.

Continuing the survey of the several national styles, we shall have to witness the final supersession of the older styles of England and France by the later developments of Italy and Flanders. We left English illumination at the close of the 14th century strengthened by a fresh infusion of apparently a foreign, perhaps Bohemian, source. The style thus evolved marks a brilliant but short-lived epoch in English art. It is not confined to MSS., but appears also in the paintings of the time, as, for example, in the portrait of Richard II. in Westminster Abbey and in that in the Wilton triptych belonging to the earl of Pembroke. Delicate but brilliant colouring, gold worked in stippled patterns and a careful modelling of the human features are its characteristics. In MSS. also the decorative borders, of the new pattern already described, are of exceptional richness. Brilliant examples of the style, probably executed for Richard himself, may be seen in a magnificent Bible (Royal MS. 1, E. ix.), and in a series of cuttings from a missal (Add. MS. 29,704-29,705) in the British Museum. But the promise of this new school was not to be fulfilled. The same style of border decoration was carried into the 15th century, and good examples are found down to the middle of it, but a general deterioration soon sets in. Two MSS. must, however, be specially mentioned as surviving instances of the fine type of work which could still be turned out early in the century; and, curiously, they are both the productions of one and the same illuminator, the Dominican, John Siferwas. The first is a fragmentary Lectionary (Brit. Mus., Harl. MS., 7026) executed for John, Lord Lovel of Tichmersh, who died in 1408; the other is the famous Sherborne Missal, the property of the duke of Northumberland, a large volume completed about the same time for the Benedictine abbey of Sherborne in Dorsetshire. Certainly other MSS. of equal excellence must have existed; but they have now perished. After the middle of the 15th century English illumination may be said to have ceased, for the native style disappears before foreign imported art. This failure is sufficiently accounted for by the political state of the country and the distractions of the War of the Roses.

In France the 15th century opened more auspiciously for the art of illumination. Brilliant colouring and the diapered background glittering with gold, the legacy of the previous century, still continue in favour for some time; the border, too, of ivy-leaf tracery still holds its own. But in actual drawing there are signs, as time advances, of growing carelessness, and the artist appears to think more of the effect of colour than of draughtsmanship. This was only natural at a time when the real landscape began to replace the background of diaper and conventional rocks and trees. In the first quarter of the century the school of Paris comes prominently to the front with such magnificent volumes as the Book of Hours of the regent, John Plantagenet, duke of Bedford, now in the British Museum; and the companion MS. known as the Sobieski Hours, at Windsor. In these examples, as is always the case with masterpieces, we see a great advance upon earlier methods. The miniatures are generally exquisitely painted in brilliant colours and the drawing is of a high standard; and in the borders now appear natural flowers intermingled with the conventional tracery--a new idea which was to be carried further as the century advanced. The Psalter executed at Paris for the boy-king Henry VI. (Cotton MS. Domitian A. xviii.) is another example of this school, rather of earlier type than the Bedford MS., but beautifully painted. In all three MSS. the borders show no lack of finish; they are of a high standard and are worthy of the miniatures. But perhaps the very finest miniature-work to be found in any MS. of French origin of this period is the breviary (Harl. MS. 2897) illuminated for John the Fearless, duke of Burgundy, who was assassinated in 1419. It could hardly be surpassed in refinement and minuteness of detail.

Development towards the modern methods of painting moves on rapidly with the century. First, the border in the middle period grows florid; the simpler ivy-spray design, which had held its position so long, is gradually pushed away by a growth of flowering scrolls, with flowers, birds and animal and insect life introduced in more or less profusion. But henceforward deterioration increases, and the border becomes subsidiary. In the case of miniatures following the old patterns of the devotional and liturgical books, a certain restraint still prevails; but with those in other works, histories and romances and general literature, where the paintings are devised by the fancy of the artist, the advance is rapid. The recognition of the natural landscape, the perception of atmospheric effects now guide the artist's brush, and the modern French school of the second half of the 15th century is fairly established. The most celebrated leaders of this school were Jean Foucquet of Tours and his sons, many of whose works still bear witness to their skill. In the MSS. of this school the influence of the Flemish contemporary art is very obvious; and before the advance of that art French illumination receded. A certain hardness of surface and want of depth characterize the French work of this time, as well as the practice of employing gilt hatching to obtain the high lights. This practice is carried to excess in the latest examples of French illumination in the early part of the 16th century, when the art became mechanical and overloaded with ornament, and thus expired.

It has been seen that the Flemish school of illumination in the 13th and 14th centuries followed the French model. In the 15th century, while the old tradition continued in force for a while, the art developed on an independent line; and in the second half of the century it exercised a widespread influence on the neighbouring countries, on France, on Holland and on Germany. This development was one of the results of the industrial and artistic activity of the Low Countries at this period, when the school of the Van Eycks and their followers, and of other artists of the great and wealthy cities, such as Bruges, Antwerp, Ghent, were so prolific. The Flemish miniatures naturally followed on the lines of painting. The new style was essentially modern, freeing itself from the traditions of medieval illumination and copying nature. Under the hand of the Flemish artist the landscape attained to great perfection, softness and depth of colouring, the leading attribute of the school, lending a particular charm and sense of reality to his out-door scenes. His closer observation of nature is testified also in the purely decorative part of his work. Flowers, insects, birds and other natural objects now frequent the border, the origin of which is finally forgotten. It ceases to be a connected growth wandering round the page; it becomes a flat frame of dull gold or colour, over which isolated objects, flowers, fruits, insects, butterflies, are strewn, painted with naturalistic accuracy and often made, by means of strong shadows, to stand out in relief against the background. This practice was soon carried to florid excess, and all kinds of objects, including jewels and personal ornaments, were pressed into the service of the border, in addition to the details copied from nature. The soft beauty of the later Flemish style proved very attractive to the taste of the day, with the result that it maintained a high standard well on into the 16th century, the only rivals being the MSS. of Italian art. The names of celebrated miniaturists, such as Memlinc, Simon Bening of Ghent, Gerard of Bruges, are associated with its productions; and many famous extant examples bear witness to the excellence to which it attained. The Grimani Breviary at Venice is one of the best known MSS. of the school; but almost every national library has specimens to boast of. Among those in the British Museum may be mentioned the breviary of Queen Isabella of Spain (Add. MS. 18,851); the Book of Hours of Juana of Castille (Add. MS. 18,852); a very beautiful Book of Hours executed at Bruges (Egerton MS. 2125); another exquisite but fragmentary MS. of the same type (Add. MS. 24,098) and cuttings from a calendar of the finest execution (Add. MS. 18,855) ascribed to Bening of Ghent; a series of large sheets of genealogies of the royal houses of Portugal and Spain (Add. MS. 12,531) by the same master and others; and late additions to the Sforza Book of Hours (Add. MS. 34,294).

But, besides the brilliantly coloured style of Flemish illumination which has been described, there was another which was practised with great effect in the 15th century. This was the simpler style of drawing in white delicately shaded to indicate the contour of figures and the folds of drapery, &c., known as _grisaille_ or _camaïeu gris_. It was not indeed confined to the Flemish schools, but was practised also to some extent and to good effect in northern France, and also in Holland and other countries; but the centre of its activity appears to have been in the Low Countries. The excellence to which it attained may be seen in the MSS. of the _Miracles de Nostre Dame_ now in Paris and the Bodleian Library, which were executed for Philip the Good, duke of Burgundy, in the middle of the 15th century.

Of the Dutch school of illumination, which was connected with that of Flanders, there is little to be said. Judging from existing examples, the art was generally of a more rustic and coarser type. There are, however, exceptions. A MS. in the British Museum (King's MS. 5) of the beginning of the 15th century contains scenes from the life of Christ in which the features are carefully modelled, very much after the style of English work of the same time; and some of the specimens of Dutch work in _camaïeu gris_ are excellent.

German illumination in the 15th century appears to have largely copied the Flemish style; but it lost the finer qualities of its pattern, and in decoration it inclined to extravagance. Where the Flemish artist was content with single flowers gracefully placed, the German filled his borders with straggling plants and foliage and with large flourished scrolls.

Italian illumination, which had developed so rapidly in the 14th century, now advanced with accelerated pace and expanded into a variety of styles, more or less local, culminating in the exquisite productions of the classical renaissance in the latter half of the 15th century. As in the other national styles of France and Flanders, the Italian miniaturist quickly abandoned the conventional for the natural landscape; but with more character both in the figure-drawing and in the actual representation of scenery. The colouring is brilliant, not of the softness of the Flemish school, but of stronger and harder body; the outlines are firm and crisp and details well delineated. The Florentine, the Lombard, the Venetian, the Neapolitan and other schools flourished; and, though they borrowed details from each other, each had something distinctive in its scheme of colouring. The border developed on several lines. The rayed gold spots or studs or pellets, which were noticed in the 14th century, are now grouped in profusion along the margins and in the interstices of delicate flowering and other designs. Another favourite detail in the composition of both initials and borders was the twining vine tendril, generally in white or gold upon a coloured ground, apparently a revival of the interlacing Lombardic work of the 11th and 12th centuries. At first, restrained and not too complex, it fills the body of initials and short borders; then it rapidly expands, and the convolutions and interlacings become more and more elaborate. Lastly came the completed solid frame into which are introduced arabesques, vignettes, candelabras, trophies, vases, medallions, antique gems, cupids, fawns, birds, &c., and all that the fancy led by the spirit of classical renaissance could suggest. Among the principal Italian MSS. of the 15th century in the British Museum there are: a copy of _Plutarch's Lives_, with miniatures in a remarkable style (Add. MS. 22,318); Aristotle's _Ethics_, translated into Spanish by Charles, prince of Viana, probably executed in Sicily about 1458 (Add. MS. 21,120); a breviary of Santa Croce at Florence, late in the century (Add. MS. 29,735); Livy's _History of the Macedonian War_, of the Neapolitan school, late in the century (Harl. MS. 3694); and, above all, the remarkable Book of Hours of Bona Sforza of Savoy of about the year 1490 (Add. MS. 34,291); besides a fair number of MSS. exhibiting the rich colouring of the Venetian school.

Like that of the French and Flemish schools, Italian illumination survived into the 16th century, and for a time showed vigour. Very elaborate borders of the classical type and of good design were still produced. But, as in other countries, it was then a dying art. The attempt to graft illumination on to books produced by the printing press, which were now displacing the hand-written volumes with which the art had always been associated, proved, except in a few rare instances, a failure. The experiment did not succeed; and the art was dead.

Spain.

It remains to say a few words respecting the book ornamentation of the Peninsula. In the earlier centuries of the middle ages there appears to have been scarcely anything worthy of note. The Mozarabic liturgies and biblical MSS. of the 9th to 12th centuries are adorned with initial letters closely allied to the primitive specimens of the Merovingian and Franco-Lombardic pattern, and coloured with the same crude tints; the larger letters also being partly composed of interlaced designs. But the style is barbaric. Such illustrative drawings as are to be found are also of a most primitive character. Moorish influence is apparent in the colours, particularly in the yellows, reds and blacks. In the later middle ages no national school of illumination was developed, owing to political conditions. When in the 15th century a demand arose for illuminated MSS., recourse was had to foreign artists. Flemish art naturally was imported, and French art on the one side and Italian art on the other accompanied it. In the breviary executed for Queen Isabella of Spain about the year 1497 (Brit. Mus., Add. MS. 18,851) we find a curious random association of miniatures and borders in both the French and the Flemish styles, the national taste for black, however, asserting itself in the borders where, in many instances, the usual coloured designs are replaced by black-tinted foliage and scrolls.

In other outlying countries of Europe the art of illumination can scarcely be said to have existed. In Slavonic countries a recollection of the Byzantine school lingered in book ornamentation, but chiefly in a degraded and extravagant system of fantastic interlacings. In the 16th century there was a revival in Russia of the Byzantine style, and the head-pieces and other ornamental details of the 11th and 12th centuries were successfully imitated.

The consideration of oriental art does not come within the scope of this article. It may, however, be noted that in Arabic and Persian MSS. of the 13th to 16th centuries there are many examples of exquisitely drawn title-pages and other ornament of intricate detail, resplendent with colour and gold, which may be ranked with western illuminations.

AUTHORITIES.--Medieval and later works dealing in part with the
technicalities of illumination are collected by Mrs Merrifield,
_Original Treatises dating from the 12th to 18th Centuries on the Art
of Painting_ (1849); see also Theophilus, _De diversis Artibus_, ed.
R. Hendrie (1847). Text-books and collections of facsimiles are Count
A. de Bastard, _Peintures et ornaments des manuscrits_, a magnificent
series of facsimiles, chiefly from Carolingian MSS. (1832-1869); Shaw
and Madden, _Illuminated Ornaments from MSS. and early Printed Books_
(1833); Noel Humphreys and Jones, _The Illuminated Books of the Middle
Ages_ (1849); H. Shaw, _Handbook of Medieval Alphabets_ (1853), and
_The Art of Illumination_ (1870); Tymms and Digby Wyatt, _The Art of
Illumination_ (1860); Birch and Jenner, _Early Drawings and
Illuminations_, with a dictionary of subjects in MSS. in the British
Museum (1879); J. H. Middleton, _Illuminated MSS. in Classical and
Medieval Times_ (1892); G. F. Warner, _Illuminated MSS. in the British
Museum_ (official publication, 1903); H. Omont, _Facsimilés des
miniatures des plus anciens MSS. grecs de la Bibl. Nationale_ (1902);
V. de Boutovsky, _Histoire de l'ornement russe du X^e au XVI^e
siècle_, including facsimiles from Byzantine MSS. (1870); J. O.
Westwood, _Facsimiles of Miniatures and Ornaments of Anglo-Saxon and
Irish MSS._ (1868); E. M. Thompson, _English Illuminated MSS._ (1895);
_Paleografia artistica di Montecassino_ (1876-1884); _Le Miniature nei
codici Cassinesi_ (1887); A. Haseloff, _Eine thüringisch-sächsische
Malereischule des 13. Jahrhunderts_ (1897); G. Schwarzenski, _Die
Regensburger Buchmalerei des 10. und 11. Jahrhunderts_ (1901);
Sauerland and Haseloff, _Der Psalter Erzbischof Egberts von Trier_
(1901).

Several of the most ancient illustrated or illuminated MSS. have been
issued wholly or partially in facsimile, viz. The _Ambrosian Homer_,
by A. Ceriani; the _Schedae Vaticanae_ and the _Codex Romanus_ of
Virgil, by the Vatican Library; the Vienna Dioscorides, in the Leiden
series of facsimiles; the Vienna Genesis, by Hartel and Wickhoff; the
Greek Gospels of Rossano, by A. Haseloff; the Ashburnham Pentateuch,
by B. von Gebhart; the Utrecht Psalter, by the Palaeographical
Society.

Facsimiles from illuminated MSS. are also included in large
palaeographical works such as Silvestre, _Universal Palaeography_, ed.
Madden (1850); the _Facsimiles_ of the Palaeographical Society
(1873-1894) and of the New Palaeographical Society (1903, &c.); and
the _Collezione paleografia Vaticana_, the issue of which was
commenced in 1905. Excellent photographic reproductions on a reduced
scale are being issued by the British Museum and by the Bibliothèque
Nationale in Paris. (E. M. T.)

ILLUMINATI (Lat. _illuminare_), a designation in use from the 15th century, and applied to, or assumed by, enthusiasts of types distinct from each other, according as the "light" claimed was viewed as directly communicated from a higher source, or as due to a clarified and exalted condition of the human intelligence. To the former class belong the _alumbrados_ of Spain. Menendez Pelayo first finds the name about 1492 (in the form _aluminados_, 1498), but traces them back to a Gnostic origin, and thinks their views were promoted in Spain through influences from Italy. One of their earliest leaders, born in Salamanca, a labourer's daughter, known as La Beata de Piedrahita, came under the notice of the Inquisition in 1511, as claiming to hold colloquies with our Lord and the Virgin; having high patrons, no decision was taken against her (_Los Heterodoxos Españoles_, 1881, lib. v.). Ignatius Loyola, while studying at Salamanca (1527) was brought before an ecclesiastical commission on a charge of sympathy with the _alumbrados_, but escaped with an admonition. Others were not so fortunate. In 1529 a congregation of unlettered adherents at Toledo was visited with scourging and imprisonment. Greater rigours followed, and for about a century the _alumbrados_ afforded many victims to the Inquisition, especially at Cordova. The movement (under the name of _Illuminés_) seems to have reached France from Seville in 1623, and attained some proportions in Picardy when joined (1634) by Pierre Guérin, curé of Saint-Georges de Roye, whose followers, known as Guérinets, were suppressed in 1635 (Hermant, _Hist. des hérésies_, 1717). Another and obscure body of _Illuminés_ came to light in the south of France in 1722, and appears to have lingered till 1794, having affinities with those known contemporaneously in this country as "French Prophets," an offshoot of the Camisards. Of different class were the so-called Illuminati, better known as Rosicrucians, who claimed to originate in 1422, but rose into notice in 1537; a secret society, combining with the mysteries of alchemy the possession of esoteric principles of religion. Their positions are embodied in three anonymous treatises of 1614 (Richard et Giraud, _Dict. de la théol. cath._). A short-lived movement of republican freethought, to whose adherents the name Illuminati was given, was founded on May-day 1776 by Adam Weishaupt (d. 1830), professor of Canon Law at Ingolstadt, an ex-Jesuit. The chosen title of this Order or Society was Perfectibilists (_Perfektibilisten_). Its members, pledged to obedience to their superiors, were divided into three main classes; the first including "novices," "minervals" and "lesser illuminati"; the second consisting of freemasons, "ordinary," "Scottish" and "Scottish knights"; the third or "mystery" class comprising two grades of "priest" and "regent" and of "magus" and "king." Relations with masonic lodges were established at Munich and Freising in 1780. The order had its branches in most countries of the European continent, but its total numbers never seem to have exceeded two thousand. The scheme had its attraction for literary men, such as Goethe and Herder, and even for the reigning dukes of Gotha and Weimar. Internal rupture preceded its downfall, which was effected by an edict of the Bavarian government in 1785. Later, the title Illuminati was given to the French Martinists, founded in 1754 by Martinez Pasqualis, and to their imitators, the Russian Martinists, headed about 1790 by Professor Schwartz of Moscow; both were Cabalists and allegorists, imbibing ideas from Jakob Boehme and Emmanuel Swedenborg (Bergier, _Dict. de théol._).

See (especially for details of the movement of Weishaupt,) P.
Tschackert, in Hauck's _Realencyklopädie_ (1901). (A. Go.*)

ILLUMINATION, in optics, the intensity of the light falling upon a surface. The measurement of the illumination is termed photometry (q.v.). The fundamental law of illumination is that if the medium be transparent the intensity of illumination which a luminous point can produce on a surface directly exposed to it is inversely as the square of the distance. The word transparent implies that no light is absorbed or stopped. Whatever, therefore, leaves the source of light must in succession pass through each of a series of spherical surfaces described round the source as centre. The same _amount_ of light falls perpendicularly on all these surfaces in succession. The amount received in a given time by a unit of surface on each is therefore inversely as the number of such units in each. But the surfaces of spheres are as the squares of their radii,--whence the proposition. (We assume here that the velocity of light is constant, and that the source gives out its light uniformly.) When the rays fall otherwise than perpendicularly on the surface, the illumination produced is proportional to the cosine of the angle of obliquity; for the area seen under a given spherical angle increases as the secant of the obliquity, the distance remaining the same.

As a corollary to this we have the further proposition that the apparent brightness of a luminous surface (seen through a transparent homogeneous medium) is the same at all distances.

The word brightness is here taken as a measure of the amount of light falling on the pupil per unit of spherical angle subtended by the luminous surface. The spherical angle subtended by any small surface whose plane is at right angles to the line of sight is inversely as the square of the distance. So also is the light received from it. Hence the brightness is the same at all distances.

The word brightness is often used (even scientifically) in another sense from that just defined. Thus we speak of a bright star, of the question--When is Venus at its brightest? &c. Strictly, such expressions are not defensible except for sources of light which (like a star) have no apparent surface, so that we cannot tell from what amount of spherical angle their light appears to come. In that case the spherical angle is, for want of knowledge, assumed to be the same for all, and therefore the brightness of each is now estimated in terms of the _whole_ quantity of light we receive from it.

The function of a telescope is to increase the "apparent magnitude" of distant objects; it does not increase the "apparent brightness." If we put out of account the loss of light by reflection at glass surfaces (or by imperfect reflection at metallic surfaces) and by absorption, and suppose that the magnifying power does not exceed the ratio of the aperture of the object-glass to that of the pupil, under which condition the pupil will be filled with light, we may say that the "apparent brightness" is absolutely unchanged by the use of a telescope. In this statement, however, two reservations must be admitted. If the object under examination, like a fixed star, have no sensible apparent magnitude, the conception of "apparent brightness" is altogether inapplicable, and we are concerned only with the total quantity of light reaching the eye. Again, it is found that the visibility of an object seen against a black background depends not only upon the "apparent brightness" but also upon the apparent magnitude. If two or three crosses of different sizes be cut out of the same piece of white paper, and be erected against a black background on the further side of a nearly dark room, the smaller ones become invisible in a light still sufficient to show the larger. Under these circumstances a suitable telescope may of course bring also the smaller objects into view. The explanation is probably to be sought in imperfect action of the lens of the eye when the pupil is dilated to the utmost. Lord Rayleigh found that in a nearly dark room he became distinctly short-sighted, a defect of which there is no trace whatever in a moderate light. If this view be correct, the brightness of the image on the retina is really less in the case of a small than in the case of a large object, although the so-called apparent brightnesses may be the same. However this may be, the utility of a night-glass is beyond dispute.

The general law that (apart from the accidental losses mentioned above) the "apparent brightness" depends only upon the area of the pupil filled with light, though often ill understood, has been established for a long time, as the following quotation from Smith's _Optics_ (Cambridge, 1738), p. 113, will show:--

"Since the magnitude of the pupil is subject to be varied by various
degrees of light, let NO be its semi-diameter when the object PL is
viewed by the naked eye from the distance OP; and upon a plane that
touches the eye at O, let OK be the semi-diameter of the greatest
area, visible through all the glasses to another eye at P, to be found
as PL was; or, which is the same thing, let OK be the semi-diameter of
the greatest area inlightened by a pencil of rays flowing from P
through all the glasses; and when this area is not less than the area
of the pupil, the point P will appear just as bright through all the
glasses as it would do if they were removed; but if the inlightened
area be less than the area of the pupil, the point P will appear less
bright through the glasses than if they were removed in the same
proportion as the inlightened area is less than the pupil. And these
proportions of apparent brightness would be accurate if all the
incident rays were transmitted through the glasses to the eye, or if
only an insensible part of them were stopt."

A very important fact connected with our present subject is: The brightness of a self-luminous surface does not depend upon its inclination to the line of sight. Thus a red-hot ball of iron, free from scales of oxide, &c., appears flat in the dark; so, also, the sun, seen through mist, appears as a flat disk. This fact, however, depends ultimately upon the second law of thermodynamics (see RADIATION). It may be stated, however, in another form, in which its connexion with what precedes is more obvious--The amount of radiation, in any direction, from a luminous surface is proportional to the cosine of the obliquity.

The flow of light (if we may so call it) in straight lines from the
luminous point, with constant velocity, leads, as we have seen, to the
expression [mu]r^(-2) (where r is the distance from the luminous
point) for the quantity of light which passes through unit of surface
perpendicular to the ray in unit of time, [mu] being a quantity
indicating the rate at which light is emitted by the source. This
represents the illumination of the surface on which it falls. The flow
through unit of surface whose normal is inclined at an angle [theta]
to the ray is of course [mu]r^(-2) cos [theta], again representing the
illumination. These are precisely the expressions for the gravitation
force exerted by a particle of mass [mu] on a unit of matter at
distance r, and for its resolved part in a given direction. Hence we
may employ an expression V = [Sigma][mu]r^(-1), which is exactly
analogous to the gravitation or electric potential, for the purpose of
calculating the effect due to any number of separate sources of light.

And the fundamental proposition in potentials, viz. that, if n be the
external normal at any point of a closed surface, the integral
[int][int](dV/dn)dS, taken over the whole surface, has the
value--4[pi][mu]0, where [mu]0 is the sum of the values of [mu] for
each source lying within the surface, follows almost intuitively from
the mere consideration of what it means as regards light. For every
source external to the closed surface sends in light which goes out
again. But the light from an internal source goes wholly out; and the
amount per second from each unit source is 4[pi], the total area of
the unit sphere surrounding the source.

It is well to observe, however, that the analogy is not quite
complete. To make it so, all the sources must lie on the same side of
the surface whose illumination we are dealing with. This is due to the
fact that, in order that a surface may be illuminated at all, it must
be capable of scattering light, i.e. it must be to some extent opaque.
Hence the illumination depends mainly upon those sources which are on
the same side as that from which it is regarded.

Though this process bears some resemblance to the heat analogy
employed by Lord Kelvin (Sir W. Thomson) for investigations in
statical electricity and to Clerk Maxwell's device of an
incompressible fluid without mass, it is by no means identical with
them. Each method deals with a substance, real or imaginary, which
flows in conical streams from a source so that the same amount of it
passes per second through every section of the cone. But in the
present process the velocity is constant and the density variable,
while in the others the density is virtually constant and the velocity
variable. There is a curious reciprocity in formulae such as we have
just given. For instance, it is easily seen that the light received
from a uniformly illuminated surface is represented by
[int][int]r^(-2) cos [theta] dS.

As we have seen that this integral vanishes for a closed surface which
has no source inside, its value is the same for all shells of equal
uniform brightness whose edges lie on the same cone.

ILLUSTRATION. In a general sense, illustration (or the art of representing pictorially some idea which has been expressed in words) is as old as Art itself. There has never been a time since civilization began when artists were not prompted to pictorial themes from legendary, historical or literary sources. But the art of illustration, as now understood, is a comparatively modern product. The tendency of modern culture has been to make the interests of the different arts overlap. The theory of Wagner, as applied to opera, for making a combined appeal to the artistic emotions, has been also the underlying principle in the development of that great body of artistic production which in painting gives us the picture containing "literary" elements, and, in actual association with literature in its printed form, becomes what we call "illustration." The illustrator's work is the complement of expression in some other medium. A poem can hardly exist which does not awaken in the mind at some moment a suggestion either of picture or music. The sensitive temperament of the artist or the musician is able to realize out of words some parallel idea which can only be conveyed, or can be best conveyed, through his own medium of music or painting. Similarly, music or painting may, and often does, suggest poetry. It is from this inter-relation of the emotions governing the different arts that illustration may be said to spring. The success of illustration lies, then, in the instinctive transference of an idea from one medium to another; the more spontaneous it be and the less laboured in application, the better.

Leaving on one side the illuminated manuscripts of the middle ages (see ILLUMINATED MSS.) we start with the fact that illustration was coincident with the invention of printing. Italian art produced many fine examples, notably the outline illustrations to the _Poliphili Hypneratomachia_, printed by Aldus at Venice in the last year of the 15th century. Other early works exist, the products of unnamed artists of the French, German, Spanish and Italian schools; while of more singular importance, though not then brought into book form, were the illustrations to Dante's _Divine Comedy_ made by Botticelli at about the same period. The sudden development of engraving on metal and wood drew many painters of the Renaissance towards illustration as a further opportunity for the exercise of their powers; and the line-work, either original or engraved by others, of Pollajuolo, Mantegna, Michelangelo and Titian has its place in the gradual enlargement of illustrative art. The German school of the 16th century committed its energies even more vigorously to illustration; and many of its artists are now known chiefly through their engravings on wood or copper, a good proportion of which were done to the accompaniment of printed matter. The names of Dürer, Burgmair, Altdorfer and Holbein represent a school whose engraved illustrations possess qualities which have never been rivalled, and remain an invaluable aid to imitators of the present day.

Progress in England.

Illustration has generally flourished in any particular age in proportion to the health and vigour of the artistic productions in other kinds. No evident revival in painting has come about, no great school has existed during the last four centuries, which has not set its mark upon the illustration of the period and quickened it into a medium for true artistic expression. The etchers of the Low Countries during the 17th century, with Rembrandt at their head, were to a great extent illustrators in their choice of subjects. In France the period of Watteau and Fragonard gave rise to a school of delicately engraved illustration, exquisite in detail and invention. In England Hogarth came to be the founder of many new conditions, both in painting and illustration, and was followed by men of genius so distinct as Reynolds on the one side and Bewick on the other. With Reynolds one connects the illustrators and engravers for whom now Bartolozzi supplies a surviving name and an embodiment in his graceful but never quite English art. But it is from Thomas Bewick that the wonderfully consistent development of English illustration begins to date. Bewick marks an important period in the technical history of wood-engraving as the practical inventor of the "tint" and "white line" method of wood-cutting; but he also happened to be an artist. His artistic device was to give local colour and texture without shadow, securing thereby a precision of outline which allowed no form to be lost. And though, in consequence, many of his best designs have somewhat the air of a specimen plate, he succeeded in bringing into black-and-white illustration an element of colour which had been wholly absent from it in the work of the 15th and 16th century German and Italian schools. Bewick's method started a new school; but the more racy qualities of his woodcuts were entirely dependent on the designer being his own cutter; and the same happy relationship gave distinct characteristics to the nearly contemporary work of William Blake and of Calvert. Blake's wonderful _Illustrations to the Book of Job_, while magnificent in their conventional rendering of light and shade, still retain the colourlessness of the old masters, as do also the more broadly handled designs to his own books of prophecy and verse; but in his woodcuts to Philips's _Pastorals_ the modern tendency towards local colour makes itself strongly felt. So wonderfully, indeed, have colour and tone been expressed in these rough wood-blocks, that more vivid impressions of darkness and twilight falling across quiet landscape have never been produced through the same materials. The pastoral designs made by Edward Calvert on similar lines can hardly be over-praised. Technically these engravings are far more able than those from which they drew their inspiration.