1869.] The Dome. 599 designed, for such a vast open area of building as the Pantheon. We will pass over a number of lesser constructions, to review the next dome in size. Santa Sophia, at Constantinople, built in the reign of Justinian, is the earliest construction of dome, after those of the Romans, and perhaps one of the most remarkable in history. The archi- tect, Anthem ius, proposed to the Em- peror to erect a church, the dome of which should far transcend that of the Pantheon. Assisted by the architect Isidorus, he made his design, which in vaulting ambition, certainly surpassed any thing that had been yet thought of. Justinian was struck with the sublimity of the thought ; and ordered the archi- tect to put it in execution. Anthemius commenced by erecting four pillars at the angles of a square, 115 feet from each other, and 112 feet high. He turned arches over each of these open- ings, and corbeled out the corners ; until, at last, he formed a true circle. On this circle, he raised his dome. Whilst con- structing this circle, or ring, he built up heavy walls, auxiliary to the piers, two against the north and two against the south sides. These walls were each 90 feet long, and built up to counteract the thrust, which was making palpable demonstrations in that direction. But scarcely had he secured himself on the north and south, when the east and west piers showed symptoms of rebellion. To meet this difficulty, he built up a half-cyliuder on the east side, and an- other on the west, over each of which he turned a half-dome, so as to abut against those arches ; conceiving such support to be sufficient. But it proved not to be equal to the occasion, for the dome pushed out, and after lingering a few months, fell ; carrying with it one of those half- domes. This casualty so affected Anthemius, that he fell into a state of despondency, which shortly ended in his death. He was succeeded in office by his coadjutor Isidorus, who at once set to work to in- crease the resisting parts, and strengthen, by filling up all open work in the span- drils, which were designed for lightness by his predecessor. But, it again gave way. He then buttressed the east and west arches, by powerfully built cloisters, on the outside of the cylindrical walls before mentioned ; from these he con- structed flying buttresses, which he in- tended should make his dome secure. But, all his devices failed ; and, before the new dome had reached half its alti- tude, it once more hurried to the ground. With his main arches either overset, or badly fractured, the poor architect stud- ied in vain to carry out the original thought of Anthemius ; but finally had to multiply small arches, and reduce the overpowering weight, by using pumice stone ; besides filling up the northern and southern arcades with more solid work, and three stories of arches. At last the dome was finished. But, how different was the plan executed from that de- signed ! Since the followers of Mohammed came into possession, and St. Sophia assumed the worship of the Mosque, the Turks have tenanted the cloisters with motley stores for merchandise ; and the whole is surrounded with narrow, filthy streets, or rather lanes, rendering it any thing but admirable externally. The dome at present, looms up beauti- fully, when Constantinople is viewed from the Golden Horn, beneath the har- monizing influence of an oriental sky. There is much allowance to be made for the failure of the original dome of St. Sophia, when we consider the crude condition of science on this subject at that time. In succeeding ages, St. Peter's, at Pome, far surpassed the great Mosque , and in diameter, was second only to the Pantheon. So much has been said by scientific and literary writers about this stupendous cathedral, as a whole, that we will avoid all allu- sion to any thing outside of that which directly concerns our present subject,
