VI
Antonio da Sangallo died on October 3, 1546, at Terni, while engaged in engineering works intended to drain the Lake Velino. Michelangelo immediately succeeded to the offices and employments he had held at Rome. Of these, the most important was the post of architect-in-chief at S. Peter's. Paul III. conferred it upon him for life by a brief dated January 1, 1547. He is there named "commissary, prefect, surveyor of the works, and architect, with full authority to change the model, form, and structure of the church at pleasure, and to dismiss and remove the working-men and foremen employed upon the same." The Pope intended to attach a special stipend to the onerous charge, but Michelangelo declined this honorarium, declaring that he meant to labour without recompense, for the love of God and the reverence he felt for the Prince of the Apostles. Although he might have had money for the asking, and sums were actually sent as presents by his Papal master, he persisted in this resolution, working steadily at S. Peter's without pay, until death gave him rest.
Michelangelo's career as servant to a Pope began with the design of that tomb which led Julius II. to destroy the old S. Peter's. He was now entering, after forty-two years, upon the last stage of his long life. Before the end came, he gave final form to the main features of the great basilica, raising the dome which dominates the Roman landscape like a stationary cloud upon the sky-line. What had happened to the edifice in the interval between 1505 and 1547 must be briefly narrated, although it is not within the scope of this work to give a complete history of the building.
Bramante's original design had been to construct the church in the form of a Greek cross, with four large semi-circular apses. The four angles made by the projecting arms of the cross were to be filled in with a complex but well-ordered scheme of shrines and chapels, so that externally the edifice would have presented the aspect of a square. The central piers, at the point of junction between the arms of the cross, supported a broad shallow dome, modelled upon that of the Pantheon. Similar domes of lesser dimensions crowned the out-buildings. He began by erecting the piers which were intended to support the central dome; but working hastily and without due regard to solid strength, Bramante made these piers too weak to sustain the ponderous mass they had to carry. How he would have rectified this error cannot be conjectured. Death cut his labours short in 1514, and only a small portion of his work remains embedded at the present day within the mightier masses raised beneath Buonarroti's cupola.
Leo X. commissioned Raffaello da Urbino to continue his kinsman's work, and appointed Antonio da Sangallo to assist him in the month of January 1517. Whether it was judged impossible to carry out Bramante's project of the central dome, or for some other reason unknown to us, Raffaello altered the plan so essentially as to design a basilica upon the conventional ground-plan of such churches. He abandoned the Greek cross, and adopted the Latin form by adding an elongated nave. The central piers were left in their places; the three terminal apses of the choir and transepts were strengthened, simplified, reduced to commonplace. Bramante's ground-plan is lucid, luminous, and exquisitely ordered in its intricacy. The true creation of a builder-poet's brain, it illustrates Leo Battista Alberti's definition of the charm of architecture, tutta quella musica, that melody and music of a graceful edifice. We are able to understand what Michelangelo meant when he remarked that all subsequent designers, by departing from it, had gone wrong. Raffaello's plan, if carried out, would have been monotonous and tame inside and out.
After the death of Raffaello in 1520, Baldassare Peruzzi was appointed to be Sangallo's colleague. This genial architect, in whose style all the graces were combined with dignity and strength, prepared a new design at Leo's request. Vasari, referring to this period of Peruzzi's life, says: "The Pope, thinking Bramante's scheme too large and not likely to be in keeping, obtained a new model from Baldassare; magnificent and truly full of fine invention, also so wisely constructed that certain portions have been adopted by subsequent builders." He reverted to Bramante's main conception of the Greek cross, but altered the details in so many important points, both by thickening the piers and walls, and also by complicating the internal disposition of the chapels, that the effect would have been quite different. The ground-plan, which is all I know of Peruzzi's project, has always seemed to me by far the most beautiful and interesting of those laid down for S. Peter's. It is richer, more imaginative and suggestive, than Bramante's. The style of Bramante, in spite of its serene simplicity, had something which might be described as shallow clearness. In comparison with Peruzzi's style, it is what Gluck's melody is to Mozart's. The course of public events prevented this scheme from being carried out. First came the pontificate of Adrian VI., so sluggish in art-industry; then the pontificate of Clement VII., so disastrous for Italy and Rome. Many years elapsed before art and literature recovered from the terror and the torpor of 1527. Peruzzi indeed returned to his office at S. Peter's in 1535, but his death followed in 1537, when Antonio da Sangallo remained master of the situation.
Sangallo had the good sense to preserve many of Peruzzi's constructive features, especially in the apses of the choir and transepts; but he added a vast vestibule, which gave the church a length equal to that of Raffaello's plan. Externally, he designed a lofty central cupola and two flanking spires, curiously combining the Gothic spirit with Classical elements of style. In order to fill in the huge spaces of this edifice, he superimposed tiers of orders one above the other. Church, cupola, and spires are built up by a succession of Vitruvian temples, ascending from the ground into the air. The total impression produced by the mass, as we behold it now in the great wooden model at S. Peter's, is one of bewildering complexity. Of architectural repose it possesses little, except what belongs to a very original and vast conception on a colossal scale. The extent of the structure is frittered by its multiplicity of parts. Internally, as Michelangelo pointed out, the church would have been dark, inconvenient, and dangerous to public morals.