Brick and Marble in the Middle Ages: Notes of Tours in the North of Italy

by George Edmund Street

There appears to me to be a certain limited extent to which we may safely go in the way of inlaying or incrustation: we may, for instance, so construct our buildings as that there may be portions of the face of their walls in which no strain will be felt, and in which this absence of strain will be at once apparent; obviously, to instance a particular place, the spaces inclosed within circles constructed in the spandrels of a line of arches can have no strain of any kind. They are portions of wall without any active function, and may safely be filled in with materials the only object of which is to be ornamental. All kinds of sunk panels inclosed within arches or tracery would come under the same head; the spaces between string-courses might also do so very frequently, if, as in old examples, the string-courses were large slabs of stones bedded into the very midst of the wall, and so capable of protecting the thin, weak slabs of marbles incrusted between them.

In Venice we have some grand examples, at S. Mark’s, of this system of incrustation filling in the whole of the space within large arches; here it is lawful, because there is no weight upon it to thrust it out of its place or disjoint it, as the least pressure most certainly always will. So far in praise of the Venetian system. But in other parts of the same building we have this system carried to a length which I cannot but think most mistaken, and which, I most heartily trust, may never find imitators here. In these the arches were constructed in brick, and then entirely covered with marble. Of course there was some difficulty in doing this, and the way in which the difficulty was met was extremely ingenious; a succession of thin slabs of marble was placed round the soffeit of the arch, having perhaps enough of the cohesion given by the form of the arch to enable them to support their own weight, and further supported by metal staples let into the joints of the brickwork. The edges of these thin slabs projected sufficiently in advance of the face of the brickwork to allow of their being worked with some kind of pattern—generally, as has before been said, a sort of dentil—and of their giving some support to the thin slices of marble with which the walls were then covered. The whole system was excessively weak; and this can nowhere be better seen than in the Fondaco de Turchi, where almost the whole of the marble facing and beautiful medallions, in which it was once so rich, have peeled off, and left nothing but the plain and melancholy substratum of brick. Few architects, I should think, would like to contemplate their work perishing in this piecemeal manner, any more than they would enjoy the thought of a west front left unfinished, like that of Sta. Anastasia at Verona, and prepared only for marble with rough, irregular, and unsightly brickwork.

It would be unjust not to say that often, very often, this system of incrustation, even when carried to the extreme limits of what seems to be lawful, wins upon our love by the exquisite delicacy and taste of the sculptured patterns, worked in low-relief, with which it is covered. The men who did this work were, perhaps, more of sculptors than of architects; and certainly it must be confessed that never in buildings in which the construction is mainly thought of, is there, so far as I know, so much elaborate thought and skill exhibited in the decorative part of the work as in buildings such as these.

Sometimes, the sculptured medallions set in the centre of a plain surface of marble are of exquisite taste and beauty; whilst here and there, as e.g. in S. Mark’s and in one or two spots in the water-front of the Ducal Palace, are examples of great beauty, of medallions formed of marbles of various colours, arranged with great refinement in some kind of geometrical pattern, which shew another and equally beautiful mode of relieving plain spaces of walling.

The plain surfaces of the walls in Venetian work were commonly either entirely inlaid, or else inlaid within a square inclosing border of projecting moulding. The inlaying was composed of a number of rectangular slabs of marble, not by any means always of the same size, supported to some extent by the projections of the inclosing marbles or by those of the archivolt, but always dependent mainly on metal cramps let into the fabric of the wall; and, when possible, these marbles were slabs cut out of the same block, and put side by side, so as to produce a kind of regular pattern wherever the veining of the marble was at all positively marked.

The other mode of introducing constructional colour in marble commends itself to one’s reason as that which is most likely to endure for ages, and as that, therefore, which ought, wherever it may be, to be adopted. The first idea of the architects of these buildings seems to have been to arrange their material with as much regard to strong contrasts of colour as was possible. The first thing they did, therefore, was to alternate the colours of every course of masonry, either simply as in the Broletto at Como[100] and in Sta. Maria Maggiore at Bergamo,[101] or as in the west front of the cathedral at Cremona, where very narrow layers of white marble are laid between each of the other courses, which are of course so much the more defined.

The description which I have already given of these works, as well as of the porch at Bergamo, will shew how regular is the way in which this system of counterchanging the colours was carried out by the purely constructional school; this is, in fact, the great mark of difference between the constructional and the incrusting school of Italian architects, the whole arrangement of coloured materials by the two schools being quite different, and producing singularly different results. The most common fault of the Venetian system of incrustation must have been that upon a general surface of plain wall you had here and there a square patch of marble surrounding a window opening; that of the other system would be, in the opinion of many, that you have too stripy an effect of colour, and that all the divisions, moreover, are horizontal.

The former must certainly have been the case wherever the incrustation did not extend over the whole surface of the walls, which was very frequently the case; but the latter is not really a fault; it was only an elaboration in a more beautiful material of the same system which we have seen pursued with such happy results by the builders of Verona in brick and stone,[102] and which we find adopted by the architects of Northern Germany in the frequent alternation of courses of red and black brick, and sometimes by our own forefathers in the coursing of flint work with stone, or in the counterchanging of red and white stones which we see in some of the Northamptonshire churches. The system was a thoroughly sound one, because it not only proceeded from and depended on the natural arrangement of the material, but afforded the best possible means for displaying the various colours which were to be used.

Probably all these systems are mainly useful now as shewing us certain principles which we may work out and apply to our own somewhat different circumstances; and surely one of our first objects ought to be the discovery of the extent of our means and opportunities, which in this matter are at the present day far beyond what is generally imagined.

It must never be forgotten by us that our forefathers had very limited means of obtaining materials from one locality and transporting them to another; and were moreover, to a great extent, unacquainted with the materials which might, if necessary, be obtained. We have not this excuse; we not only know what materials we may obtain, but we have at the same time marvellous facilities for their conveyance between all parts of the country; and we know also how much has been done of old in other countries by using them in a proper way.