CHAPTER I.
Of the different kinds of Stone which are used by Architects for ornamental details, and in Sculpture for Statues; that is, Of Porphyry, Serpentine, Cipollaccio, Breccia, Granites, Paragon or Test-stone, Transparent Marbles, White Marbles and Veined Marbles, Cipollini, Saligni, Campanini, Travertine, Slate, Peperigno, Ischia Stone, Pietra Serena and Pietra Forte.
§ 1. The author’s object in the Discussion of Architecture.
How great is the utility of Architecture it does not fall to me to tell, since the subject has been treated at length and most carefully by many writers. For this reason, leaving on one side the limes, sands, wood, iron armatures, mode of preparing the foundations, as well as everything else that is used in a building; disregarding also the questions of water and localities and sites, already enlarged on by Vitruvius[[3]] and by our own Leon Battista Alberti,[[4]] I shall only discuss, for the use of our artificers and for whoever likes to know, the essential qualities of buildings, and in what proportions they should be put together and of what parts composed in order to obtain that graceful beauty that is desired. In short, I shall collect all that seems to me necessary for the purpose in view.
§ 2. Of the working of hard stones, and first of Porphyry.
In order that the great difficulty of working very hard and compact stones may be clearly understood, we shall treat distinctly but briefly of every variety which our workmen handle, and first of porphyry.[[5]] This is a red stone, with minute white specks, brought into Italy from Egypt, where it is generally believed that the stone when quarried is softer than it is after it has been exposed to rain, frost and sunshine; because all these influences make it harder and more difficult to work.[[6]] Of this stone numberless works are to be seen, some of them shaped with the chisel, some sawn into shape, and some again gradually worked up by means of wheels and emery. There are many different examples in divers places; for instance, square, round, and other pieces smoothed for pavements, statues for edifices, a great number of columns large and small, and fountains with various masks, all carved with the greatest care. There are also sarcophagi still extant, with figures in low and half relief, laboriously wrought, as at the temple of Bacchus,[[7]] outside Rome, by Sant’ Agnese, where is said to be the sarcophagus of Santa Costanza, daughter of the Emperor Constantine, on which are carved many figures of children with grapes and vineleaves, that testify how great was his labour who worked them in a stone so hard. There is another example in an urn, near to the door known as the Porta Santa in San Giovanni in Laterano, which is decorated with scenes containing a great number of figures.[[8]] There is also in the piazza della Ritonda a very beautiful urn made for sepulchral purposes[[9]] that is worked with great care and diligence. It is of extremely graceful and beautiful form, and is very different from the others. In the house of Egizio and of Fabio Sasso[[10]] there used to be a seated figure, measuring three and a half braccia, preserved to our days with the remains of the other statues in the Casa Farnese.[[11]] In the courtyard also of the Casa la Valle,[[12]] over a window, is a she-wolf most excellently sculptured,[[13]] and, in the garden of the same house, the two prisoners bound, each four braccia in height,[[14]] executed in this same porphyry by the ancients with extraordinary skill. These works are lavishly praised to-day by all skilled persons, knowing, as they do, the difficulty the workers had in executing them owing to the hardness of the stone.
In our day stone of this sort is never wrought to perfection,[[15]] because our artificers have lost the art of tempering the chisels and other instruments for working them. It is true that they can still, with the help of emery, saw drums of columns into slices, and cut other pieces to be arranged in patterns for floors, and make various other ornaments for buildings. The porphyry is reduced little by little by means of a copper saw, without teeth, drawn backwards and forwards between two men, which, with the aid of emery reduced to powder, and kept constantly wet with water, finally cuts its way through the stone.[[16]] Although at different times many ingenious attempts have been made to find out the method of working porphyry used by the ancients,[[17]] all have been in vain, and Leon Battista Alberti, the first to make experiments therein not however in things of great moment, did not find, among the many tempering-baths that he put to the test, any that answered better than goats’ blood; because, though in the working it removed but little of that hardest of stones and was always striking sparks of fire, it served him nevertheless so far as to enable him to have carved, in the threshold of the principal door of Santa Maria Novella in Florence, the eighteen antique letters, very large and well proportioned, which are seen on the front of the step, in a piece of porphyry. These letters form the words Bernardo Oricellario.[[18]] And because the edge of the chisel did not suit for squaring the corners, or giving the necessary polish and finish, he had a little revolving drill made, with a handle like a spit, which was easily worked by placing the said handle against the chest, and putting the hands into the crank in order to turn it.[[19]] At the working end, instead of a chisel or bit, he fixed copper discs, larger or smaller according to need, and these, well sprinkled with emery, gradually reduced and smoothed the stone, producing a fine surface and finishing the corners, the drill all the while being dexterously twirled by the hand. But all this effort cost so much time, that Leon Battista lost heart, and did not put his hand to anything else, either in the way of statues, or vases, or other delicate work. Others, afterwards, who set themselves to smoothing stones and restoring columns by the same special process, have done it in this way. They make for the purpose large and heavy hammers, with the points of steel, keenly tempered with goats’ blood, and worked in the manner of diamond points; with these they carefully tap on the porphyry, and ‘scabbling’ it, or working it down, little by little the best way they can, finally reduce it, with much time and trouble, to the round or the flat, as the workman chooses,—not however to the form of statues, because of this we have lost the art—and they polish it with emery and leather, scouring it till there comes a lustre very clear and well finished.
Fig. 1.—Inscribed Porphyry Tablet at Santa Maria Novella, Florence.
Now although every day refinements are being made on human inventions, and new things enquired into, yet even the moderns, who from time to time have tried fresh methods of carving porphyry, various tempering-baths, and very carefully refined steels, have, as was said above, up till recent years laboured in vain. Thus in the year 1553 Pope Julius III, having been presented by Signor Ascanio Colonna[[20]] with a very handsome antique porphyry basin, measuring seven braccia across, ordered it to be restored, for some pieces were missing, that it might adorn his vineyard: the work was undertaken, and many things tried by the advice of Michelagnolo Buonarroti and of other excellent masters, but after a great length of time the enterprise was despaired of, chiefly because it was found impossible to preserve some of the arrises, a matter essential to the undertaking: Michelagnolo, moreover, even though accustomed to the hardness of stones, gave up the attempt, as did all the others, and nothing more was done.
Plate II
PRINCIPAL DOORWAY AT S. MARIA NOVELLA, FLORENCE
Showing the position of the inscribed porphyry tablet on the riser or the step
At last, since no other thing in our days was lacking to the perfection of our arts, except the method of satisfactorily working porphyry, that not even this should still be to seek, it was rediscovered in the following manner. In the year 1555, Duke Cosimo, wishing to erect a fountain of remarkable beauty in the court of his principal palace in Florence, had excellent water led there from the Pitti Palace and Garden, and ordered a basin with its pedestal to be made for the said fountain from some large pieces of porphyry found among broken fragments. To make the working of it more easy to the master, he caused an extract to be distilled from an herb, the name of which is unknown to me, and this extract had such virtue, that red-hot tools when plunged into it acquired the hardest possible temper. With the aid of this process then, Francesco del Tadda, the carver of Fiesole,[[21]] executed after my design the basin of the said fountain, which is two and a half braccia in diameter,[[22]] together with its pedestal, just as it may be seen to-day in the above-named palace.[[23]] Tadda, judging that the secret imparted to him by the duke was very precious, set himself to put it to the test by carving something, and he has succeeded so well that in a short time he has made, in three ovals, life-size portraits in half relief of Duke Cosimo and of the duchess Leonora, and a head of Christ, executed so perfectly that the hair and beard, most difficult to reproduce in carving, are finished in a manner equal to that of the ancients. The Duke was talking one day of these works with Michelagnolo[[24]] when his Excellency was in Rome, and Buonarroti would not believe in them; therefore, by the Duke’s order, I sent the head of Christ to Rome where it was seen by Michelagnolo with great wonder, who praised it highly and rejoiced greatly to see the sculpture of our time enriched by this rare gift, which until our day had been searched for in vain. Tadda has recently finished the head of the elder Cosimo de’ Medici[[25]] in an oval, like those mentioned above, and he has executed and continues to execute many other similar works.
All that remains to be said of porphyry is that, because the quarries are now lost to knowledge,[[26]] it is necessary to make use of what is left of it in the form of ancient fragments, drums of columns and other pieces; and that in consequence he who works in porphyry must ascertain whether or not it has been subjected to the action of fire, because if it have, although it does not completely lose its colour, nor crumble away, it lacks much of its natural vividness and never takes so good a polish as when it has not been so subjected; and, what is worse, it easily fractures in the working. It is also worth knowing, as regards the nature of porphyry, that, if put into the furnace, it does not burn away (non si cuoce),[[27]] nor allow other stones round it to be thoroughly burnt; indeed, as to itself, it grows raw (incrudelisce) as is shown in the two columns the men of Pisa gave to the Florentines in the year 1117 after the acquisition of Majorca. These columns now stand at the principal door of the church of San Giovanni; they are colourless and not very well polished in consequence of having passed through fire, as Giovanni Villani relates in his history.[[28]]
Plate III
PORTRAIT IN PORPHYRY OF COSIMO ‘PATER PATRIAE’
BY FRANCESCO DEL TADDA
§ 3. Of Serpentine.
After porphyry we come to serpentine,[[29]] which is a green stone, rather dark, with little crosses long and yellowish all through its texture. The artificers busy themselves with making columns and slabs for pavements in edifices from it, in the same way as from porphyry. It is never seen carved into figures, although it is very often used for the bases of columns, the pedestals of tables, and other works of a ruder kind. Though this sort of stone is liable to fracture, and is harder than porphyry, it is sweeter to work and involves less labour. Serpentine is quarried in Egypt and Greece and the sound pieces are not very large; consequently no work of greater dimensions than three braccia in any direction is ever seen of serpentine, and such works as exist are slabs and pieces of pavement. A few columns are found also but not very massive nor thick, as well as some masks and sculptured brackets, but figures never. This stone is worked in the same manner as porphyry.
§ 4. Of Cipollaccio.
Softer than serpentine is cipollaccio,[[30]] a stone quarried in various places; it is of a crude yellowish green colour and has within it some square black marks, large and small, and also biggish white marks. Of this material one may see in various places columns both massive and slender, as well as doors and other ornaments, but not figures. There is a fountain of this stone in Rome in the Belvedere, that is to say a niche in a corner of the garden where are the statues of the Nile and of the Tiber;[[31]] Pope Clement VII had this niche made, after a design by Michelagnolo,[[32]] to adorn the statue of a river god that it might look very beautiful in this setting made in imitation of natural rocks, as indeed it actually does. Cipollaccio is also sawn into panels, round and oval, and into similar pieces which, when arranged with other stones in pavements and other flat surfaces, make lovely compositions. It takes a polish like porphyry and serpentine and is sawn in the same manner. Numberless pieces of it are found in Rome, buried under the ruins; these come to light daily and thus of ancient things modern works are made, such as doors and other ornamental details, which, wherever placed, are decorative and very beautiful.
§ 5. Of Breccia (‘Mischio,’ Conglomerate).
Here is now another stone, called ‘mischio’ (breccia),[[33]] from the mixture of various stones coagulated together and made one by time and by the mordant action of water. It is found in abundance in several places, as in the mountains of Verona, in those of Carrara, and of Prato in Tuscany, and in the hills of the Impruneta in the neighbourhood of Florence.[[34]] But the best and choicest breccias have been found, not long ago, at San Giusto at Monte Rantoli, five miles distant from Florence.[[35]] In this material Duke Cosimo has commissioned me to decorate all the new rooms of the palace with doors and chimney pieces, and the effect is most beautiful. Also for the garden of the Pitti, very fine columns seven braccia high have been quarried from the same place, and I am astonished that in this stone such large pieces should be found free from flaws.[[36]] Being of the nature of limestone, it takes a beautiful polish and in colour inclines to a reddish purple streaked with white and yellowish veins. But the finest examples of all are in Greece and Egypt,[[37]] where the stone is much harder than ours in Italy, and it is found in as many different colours as mother nature has delighted and still delights to produce in all perfection. In the breccias formed in this way one sees at Rome at the present day both ancient and modern works, such as columns, vases, fountains, door ornaments, and various inlays on buildings, as well as many pieces in the pavements. There are various sorts, of many colours; some draw to yellow and red, others to white and black, others again to grey and white speckled with red and veined with numerous colours; then there are certain reds, greens, blacks and whites which are oriental: and of this sort of stone the Duke has an antique urn, four and a half braccia across, in his garden at the Pitti, a thing most precious, being as I said of oriental breccia very beautiful and extremely hard to work.[[38]] Such stones are all very hard, and exquisite in colour and quality, as is shown by the two columns, twelve braccia high at the entrance of St. Peter’s in Rome, which support the first arcades of the aisles, one on each side.[[39]] Of this stone, the kind which is found in the hills of Verona, is very much softer than the oriental; and in that place is quarried a sort which is reddish, and inclines towards a vetch colour.[[40]] All these kinds are worked easily in our days with the tempering-baths and the tools used for our own local stones. Windows, columns, fountains, pavements, door posts and mouldings are made of them, as is seen in Lombardy and indeed throughout Italy.
§ 6. Of Granite.
There is another sort of extremely hard stone, much coarser and speckled with black and white and sometimes with red, which, on account of its grain and consistency, is commonly called granite.[[41]] In Egypt it exists in solid masses of immense size that can be quarried in pieces incredibly long, such as are seen now-a-days in Rome in obelisks, needles, pyramids, columns, and in those enormous vessels for baths which we have at San Pietro in Vincola, at San Salvadore del Lauro and at San Marco.[[42]] It is also seen in columns without number, which for hardness and compactness have had nothing to fear from fire or sword, so that time itself, that drives everything to ruin, not only has not destroyed them but has not even altered their colour. It was for this reason that the Egyptians made use of granite in the service of their dead, writing on these obelisks in their strange characters the lives of the great, to preserve the memory of their prowess and nobility.
From Egypt there used also to come another variety of grey granite, where the black and white specks draw rather towards green. It is certainly very hard, not so hard however, but that our stonecutters, in the building of St. Peter’s, have made use of the fragments they have found, in such a manner that by means of the temper of the tools at present adopted, they have reduced the columns and other pieces to the desired slenderness and have given them a polish equal to that of porphyry.
Many parts of Italy are enriched with this grey granite, but the largest blocks found are in the island of Elba, where the Romans kept men continually employed in quarrying countless pieces of this rock.[[43]] Some of the columns of the portico of the Ritonda are made of it, and they are very beautiful and of extraordinary size.[[44]] It is noticed that the stone when in the quarry is far softer and more easy to work than after it has lain exposed.[[45]] It is true that for the most part it must be worked with picks that have a point, like those used for porphyry, and at the other end a sharp edge like a toothed chisel.[[46]] From a piece of this granite which was detached from the mass, Duke Cosimo has hollowed out a round basin twelve braccia broad in every direction and a table of the same length for the palace and garden of the Pitti.[[47]]
§ 7. Of Paragon (Touchstone).[[48]]
A kind of black stone, called paragon, is likewise quarried in Egypt and also in some parts of Greece. It is so named because it forms a test for trying gold; the workman rubs the gold on this stone and discerns its colour, and on this account, used as it is for comparing or testing, it comes to be named paragon, or indexstone (a). Of this there is another variety, with a different grain and colour, for it has, almost but not quite, the tint of the mulberry, and does not lend itself readily to the tool. It was used by the ancients for some of those sphinxes and other animals seen in various places in Rome, and for a figure of greater size, a hermaphrodite in Parione,[[49]] alongside of another most beautiful statue of porphyry.[[50]] This stone is hard to carve, but is extraordinarily beautiful and takes a wonderful polish (b). The same sort is also to be found in Tuscany, in the hills of Prato, ten miles distant from Florence (c), and in the mountains of Carrara. On modern tombs many sarcophagi and repositories for the dead are to be seen of it; for example, in the principal chapel in the Carmine at Florence, where is the tomb of Piero Soderini (although he is not within it) made of this stone, and a canopy too of this same Prato touchstone, so well finished and so lustrous that it looks like a piece of satin rather than a cut and polished stone (d). Thus again, in the facing which covers the outside of the church of Santa Maria del Fiore in Florence, all over the building, there is a different kind of black marble (e) and red marble (f), but all worked in the same manner.
§ 8. Of Transparent Marbles for filling window openings.
Some sorts of marble are found in Greece and in all parts of the East, which are white and yellowish, and very transparent. These were used by the ancients for baths and hot-air chambers and for all those places which need protection against wind, and in our own days there are still to be seen in the tribune of San Miniato a Monte, the abode of the monks of Monte Oliveto, above the gates of Florence, some windows of this marble, which admit light but not air.[[51]] By means of this invention people gave light to their dwellings and kept out the cold.
§ 9. Of Statuary Marbles.
From the same quarries[[52]] were taken other marbles free from veins, but of the same colour, out of which were carved the noblest statues. These marbles were of a very fine grain and consistency, and they were continually being made use of by all who carved capitals and other architectural ornaments. The blocks available for sculpture were of great size as appears in the Colossi of Montecavallo at Rome,[[53]] in the Nile[[54]] of the Belvedere and in all the most famous and noble statues. Apart from the question of the marble, one can recognize these to be Greek from the fashion of the head, the arrangement of the hair, and from the nose, which from its juncture with the eyebrows down to the nostril is somewhat square.[[55]] This marble is worked with ordinary tools and with drills, and is polished with pumice stone, with chalk from Tripoli, and with leather and wisps of straw.
In the mountains of Carrara in the Carfagnana,[[56]] near to the heights of Luni, there are many varieties of marble, some black,[[57]] some verging towards grey, some mingled with red and others again with grey veins.[[58]] These form an outer crust over the white marbles, and they take those colours, because they are not refined, but rather are smitten by time, water and the soil. Again, there are other sorts of marble, called ‘cipollini,’[[59]] ‘saligni,’ ‘campanini’ and ‘mischiati.’[[60]] The most abundant kind is pure white and milky in tone; it is easy to work and quite perfect for carving into figures. Enormous blocks lie there ready to be quarried, and in our own days, pieces measuring nine braccia have been hewn out for colossal statues. Two of these colossi have recently been sculptured, each from a single block. The one is Michelagnolo’s ‘David,’ which is at the entrance of the Ducal Palace in Florence;[[61]] the other is the ‘Hercules and Cacus’ from the hand of Bandinello standing at the other side of the same entrance. Another block of nine braccia in length was taken out of the quarry a few years ago, in order that the same Baccio Bandinello should carve a figure of Neptune for the fountain which the Duke is having erected on the piazza. But, Bandinello being dead, it has since been given to Ammannato, an excellent sculptor, for him likewise to carve a Neptune out of it.[[62]] But of all these marbles, that of the quarry named Polvaccio,[[63]] in the place of that name, has the fewest blemishes and veins and is free from those knots and nuts which very often occur in an extended surface of marble—occasioning no little difficulty to the worker, and spoiling the statues even when they are finished. From the quarries of Seravezza, near to Pietrasanta, there have been taken out a set of columns, all of the same height, destined for the façade of San Lorenzo at Florence, which is now sketched out in front of the door of that church;[[64]] one of these columns is to be seen there, the rest remain, some in the quarry, some at the seashore.
Fig. 2.—Tools mentioned by Vasari, etc.
A, B, Models of Tools used in Egypt at the present day for working hard stones. C, The pick referred to by Vasari, p. [41]. D, A burin or graver. E-J, Tools in actual use in a stone-cutter’s yard at Settignano:
E, Subbia, a point. F, Calcagnuolo, a toothed chisel. G, Gradina, a broader toothed chisel. H, Scarpello, a chisel. J, Trapano, a drill.
But returning to the quarries of Pietrasanta,[[65]] I say that they were the quarries in which all the ancients worked, and no other marbles but these were used for their statues by those masters, who were so excellent. While the masses were being hewn out, they were always at work, blocking out figures in the rough on the stones while they were still in the quarry. The remains of many of these can be seen even yet in that place.[[66]] This same marble, then, the moderns of to-day use for their statues, not only in Italy, but in France, England, Spain and Portugal, as can be seen to-day in the tomb executed in Naples by Giovanni da Nola, the excellent sculptor, for Don Pietro di Toledo, viceroy of that kingdom, to whom all the marbles were presented, and sent to Naples by Duke Cosimo de’ Medici.[[67]] This kind of marble has in itself larger available pieces and is more yielding and softer to work and receives a finer polish than any other marble. It is true that occasionally the workman meets with flaws called by the sculptors ‘smerigli’ (emery veins) which usually cause the tools to break. The blocks are first roughed into shape, by a tool called ‘subbia’ (point)[[68]] which is pointed like a stake in facets, and is heavier or lighter as the case may be. At the next stage are used chisels, named ‘calcagnuoli’ (toothed chisels), which have a notch in the middle of the edge of the blade; after that finer and finer tools with more teeth are used to score the marble, after which it is smoothed with another chisel called ‘gradina,’ (broader toothed chisel) used to reduce and refine the figures. The tooth marks left in the marble are removed with iron rasps straight and curved, and thus at last, by polishing gradually with pumice stone the surface aimed at is attained. In order not to fracture the marble, all the drill-holes are made with drills of different sizes weighing from twelve pounds each even to twenty, according to the size of the hole needed,[[69]] and they serve to finish every sort of work and to bring it to perfection.
Of certain white marbles, streaked with grey,[[70]] sculptors and architects make ornaments for doors and columns for houses and the same are used also for pavements and for facings of large buildings, and for all sorts of things. All the marbles called ‘mischiati’[[71]] are used for the same purposes.
§ 10. Of Cipollino Marble.[[72]]
The cipollini marbles are another kind, different in grain and colour, and found in other places besides Carrara. Most of them are greenish, and full of veins; they are useful for various things, but not for figures. Those which the sculptors call ‘saligni,’[[73]] because they are partly transparent, and have that lustrous appearance seen in salt, have something of the nature of stalagmite, and are troublesome enough to make figures of; because the grain of the stone is rough and coarse, or because in damp weather water drops from it continually or else it sweats. The ‘campanini’ marbles are so named because they sound like a bell under the hammer and give out a sharper note than other marbles.[[74]] These are hard and crack more easily than the kinds above mentioned. They are quarried at Pietrasanta.[[75]] Again at Seravezza[[76]] in many places and at Campiglia[[77]] there are marbles excavated, which are for the most part excellent for ashlar work and even fairly good sometimes for statues.
§ 11. Of White Pisan Marble.
A kind of white marble, akin to limestone, is found likewise at Monte San Giuliano near Pisa.[[78]] It has been used for covering the outside walls of the Duomo and the Camposanto of Pisa, as well as for many other ornaments to be seen in that city. Formerly the said marbles were brought to Pisa from the hill at San Giuliano with trouble and expense, but now it is different, because Duke Cosimo, in order to make the district more healthy and also to facilitate the carriage of the marbles and other stones taken from those mountains, has turned into a straight canal the river Osoli and many other streams, which used to rise in those plains and do damage to the country. By means of this canal, the marbles, either worked or rough, can be easily conveyed, at a trifling cost, and with the greatest advantage to the city which is now almost restored to its former magnificence, thanks to the said Duke, who has no object more dear to him than that of improving and restoring the city, which was falling into ruins, before His Excellency became its lord.[[79]]
§ 12. Of Travertine.
There is another sort of stone called travertine, which is much used for building and also for carvings of various sorts. It is always being quarried in many places throughout Italy, as in the neighbourhood of Lucca, at Pisa, and round about Siena; but the largest blocks and the best, that is, those which are most easily worked, are taken from above the river Teverone at Tivoli.[[80]] The stone is all a kind of coagulation of earth and of water, which by its hardness and coldness congeals and petrifies not only earth, but stumps and branches and leaves of trees. On account of the water that remains within the stones—which never can be dry so long as they lie under water—they are full of pores which give them a spongy and perforated appearance, both within and without.
Of travertine the ancients constructed their most wonderful buildings, for example, the Colosseum, and the Treasury by the church of Ss. Cosimo e Damiano[[81]] and many other edifices. They used it without stint for the foundations of their public buildings, and in working these basements, they were not too fastidious in finishing them carefully, but left them rough, as in rustic work; and this they did perhaps because so treated they possess a certain grandeur and nobility of their own.[[82]] But in our days there has been found one who has worked travertine most skilfully, as was formerly seen in that round temple, begun but never finished, save only the basement, on the piazza of San Luigi de’ Francesi in Rome.[[83]] It was undertaken by a Frenchman named Maestro Gian, who studied the art of carving in Rome and became so proficient, that his work in the beginning of this temple could stand comparison with the best things, either ancient or modern, ever seen carved in travertine. He carved astrological globes, salamanders in the fire, royal emblems, devices of open books showing the leaves, and carefully finished trophies and masks. These, in their own place, bear witness to the excellence and quality of the stone which, although it is coarse, can be worked as freely as marble. It possesses a charm of its own, owing to the spongy appearance produced by the little cavities which cover the surface and look so well. This unfinished temple being left imperfect, was razed by the French, and the said stones and other pieces that formed part of its construction were placed in the façade of the church of San Luigi[[84]] and in some of its chapels, where they are well arranged, and produce a beautiful effect.
Travertine is excellent for walls, because after it is built up in squared courses and worked into mouldings, it can be entirely covered with stucco[[85]] and thereafter be impressed with any designs in relief that are desired, just as the ancients did in the public entrances to the Colosseum[[86]] and in many other places; and as Antonio da San Gallo has done in the present day in the hall of the Pope’s palace, in front of the chapel,[[87]] where he has faced the travertine with stucco bearing many excellent devices. More than any other master however has Michelagnolo Buonarroti ennobled this stone in the decoration of the court of the Casa Farnese.[[88]] With marvellous judgement he has used it for windows, masks, brackets, and many other such fancies; all these are worked as marble is worked and no other similar ornament can be seen to excel this in beauty. And if these things are rare, more wonderful than all is the great cornice on the front façade of the same palace, than which nothing more magnificent or more beautiful can be sought for. Michelagnolo has also employed travertine for certain large chapels on the outside of the building of St. Peter’s, and in the interior, for the cornice that runs all round the tribune; so finished is this cornice that not one of the joints can be perceived, everyone therefore can well understand with what advantage to the work we employ this kind of stone. But that which surpasses every other marvel is the construction in this stone of the vault of one of the three tribunes in St. Peter’s; the pieces composing it are joined in such a manner that not only is the building well tied together with various sorts of bonds, but looked at from the ground it appears made out of a single piece.[[89]]
§ 13. Of Slates.
We now come to a different order of stones, blackish in colour and used by the architects only for laying on roofs. These are thin flags produced by nature and time near the surface of the earth for the service of man. Some of these are made into receptacles, built up together in such a manner that the pieces dovetail one into the other. The vessels are filled with oil according to their holding capacity and they preserve it most thoroughly. These slates are a product of the sea coast of Genoa, in a place called Lavagna;[[90]] they are excavated in pieces ten braccia long and are made use of by artists for their oil paintings, because pictures painted on slate last much longer than on any other material, as we shall discuss more appropriately in the chapters on painting.
§ 14. Of Peperino.[[91]]
We shall also refer in a future chapter to a stone named piperno or more commonly peperigno, a blackish and spongy stone, resembling travertine, which is excavated in the Roman Campagna. It is used for the posts of windows and doors in various places, notably at Naples and in Rome; and it also serves artists for painting on in oil, as we shall relate in the proper place. This is a very thirsty stone and indeed more like cinder than anything else.
§ 15. Of the Stone from Istria.[[92]]
There is moreover quarried in Istria a stone of a livid white, which very easily splits, and this is more frequently used than any other, not by the city of Venice alone, but by all the province of Romagna, for all works both of masonry and carving. It is worked with tools and instruments longer than those usually employed, and chiefly with certain little hammers that follow the cleavage of the stone, where it readily parts. A great quantity of this kind of stone was used by Messer Jacopo Sansovino, who built the Doric edifice of the Panattiera[[93]] in Venice, and also that in the Tuscan style for the Zecca (mint) on the Piazza of San Marco.[[94]] Thus they go on executing all their works for that city, doors, windows, chapels, and any other decorations that they find convenient to make, notwithstanding the fact that breccias and other kinds of stone could easily be conveyed from Verona, by means of the river Adige. Very few works made of these latter materials are to be seen, because of the general use of the Istrian stone, into which porphyry, serpentine and other sorts of breccias are often inlaid, resulting in compositions which are very ornamental. This stone is of the nature of the limestone called ‘alberese,’ not unlike that of our own districts, and as has been said it splits easily.
§ 16. Of Pietra Serena.
There only remains now the pietra serena and the grey stone called ‘macigno’[[95]] and the pietra forte which is much used in the mountainous parts of Italy, especially in Tuscany, and most of all in Florence and her territory. The stone that they call pietra serena[[96]] draws towards blue or rather towards a greyish tint. There are quarries of it in many places near Arezzo, at Cortona, at Volterra, and throughout the Apennines. The finest is in the hills of Fiesole, and it is obtained there in blocks of very great size, as we see in all the edifices constructed in Florence by Filippo di Ser Brunellesco, who had all the stones needed for the churches of San Lorenzo and of Santo Spirito quarried there, and also an unlimited quantity which are in every building throughout the city. It is a very beautiful stone to look at, but it wastes away and exfoliates where it is subjected to damp, rain, or frost. Under cover however it will last for ever. Much more durable than this and of finer colour is a sort of bluish stone, in our day called ‘pietra del fossato.’[[97]] When quarried, the first layer is gravelly and coarse, the second is never free from knots and fissures, the third is admirable being much finer in grain. Michelagnolo used this, because of its yielding grain, in building the Library and Sacristy of San Lorenzo for Pope Clement, and he has had the mouldings, columns, and every part of the work executed with such great care that even if it were of silver it would not look so well.[[98]] The stone takes on a very fine polish, so much so that nothing better in this kind of material could be wished for. On this account it was forbidden by law that the stone be used in Florence for other than public buildings, unless permission had been obtained from the governing authorities.[[99]] The Duke Cosimo has had a great quantity of this stone put into use, as for example, in the columns and ornaments of the loggia of the Mercato Nuovo, and for the work begun by Bandinello in the great audience chamber of the palace and also in the other hall which is opposite to it; but the greatest amount, more than ever used elsewhere, has been taken by his Excellency for the Strada de’ Magistrati,[[100]] now in construction, after the design and under the direction of Giorgio Vasari of Arezzo. This stone demands as much time for working it as marble. It is so hard that water does not affect it and it withstands all other attacks of time.
Besides this there is another sort called pietra serena, found all over the hill, which is coarser, harder, and not so much coloured, and contains certain knots in the stone. It resists the influence of water and frost, and is useful for figures and carved ornaments. Of this is carved La Dovizia (Abundance), a figure from the hand of Donatello on the column of the Mercato Vecchio in Florence;[[101]] and it serves also for many other statues executed by excellent sculptors, not only in this city, but throughout the territory.
§ 17. Of Pietra Forte.[[102]]
The pietra forte is quarried in many places; it resists rain, sun, frost, and every trial, and demands time to work it, but it behaves very well; it does not exist in very large blocks.[[103]] Both by the Goths[[104]] and by the moderns have been constructed of this stone the most beautiful buildings to be found in Tuscany, as can be seen in Florence in the filling of the two arches, which form the principal doors of the oratory of Orsanmichele,[[105]] for these are truly admirable things and worked with the utmost care. Of this same stone there are throughout the city, as has been said, many statues and coats of arms,[[106]] as for instance in the Fortress and various other places. It is yellowish in colour with fine white veins that add greatly to its attractiveness, and it is sometimes employed for statues where there are to be fountains, because it is not injured by water. The walls of the palace of the Signori, the Loggia, and Orsanmichele are built of it, also the whole interior of the fabric of Santa Maria del Fiore, as well as all the bridges of our city, the Palace of the Pitti and that of the Strozzi families. It has to be worked with picks because it is very compact. Similarly, the other stones mentioned above must be treated in the manner already explained for the working of marble and other sorts of stones.
§ 18. Conclusion of Chapter.
After all however, good stones and well tempered tools apart, the one thing essential is the art, the intelligence, and the judgement of those who use them, for there is the greatest difference between artists, although they may all use the same method, as to the measure of grace and beauty they impart to the works which they execute. This enables us to discern and to recognize the perfection of the work done by those who really understand, as opposed to that of others who know less. As, therefore, all the excellence and beauty of the things most highly praised consist in that supreme perfection given to them by those who understand and can judge, it is necessary to strive with all diligence always to make things beautiful and perfect—nay rather, most beautiful and most perfect.