The archæology of Rome, Part 8

by John Henry Parker

There is no probability in the theory of Fabretti, that the great aqueduct coming from Gabii, on the eastern side of Rome[186], was the one mentioned in the life of Alexander Severus as made by him to carry water to his thermæ, near those of Agrippa, in the Campus Martius, on the northern side of Rome. A branch from the Virgo on the Pincian, or from one of the great reservoirs on the eastern side of Rome, could be made at a tenth part of the cost. There is some reason to believe that there was such a branch passing near the Barberini palace.

Another branch may very well have been made from the great aqueducts between the Porta Maggiore and the Porta S. Lorenzo, to the Nymphæum of Alexander Severus, on the Esquiline in Regio V. An inscription relating to this is said to have been found at the piscina in the garden of S. Croce[187]. It is far more probable that this inscription was found on the wall of the great reservoir, on the other side of the Via di S. Maria Maggiore, near the Minerva Medica, where other reservoirs of extensive thermæ of the third century are visible[188]. These were supplied with water from other reservoirs just within the Porta Maggiore belonging to the different aqueducts; the Anio Vetus, the Marcian, and the Claudian, all appear to have contributed their share. The one specially called Alexandrina was probably the lofty one carried upon a tall arcade, from the reservoir of the Claudia near the Baker’s tomb,—forming part of the present city wall. The lower part of the piers of the arcade of this period may be seen built up in the wall; the arches lead to another reservoir between that and the building called the Temple of Minerva Medica, and are there brought to an end, just on the south side of the new arches made for the railway. The specus or conduit, and the arches for it, on these brick piers of the third century, have been rebuilt for the Aqua Felice, in the same rough way as that specus is usually built; but, as that conduit is carried on to the Porta S. Lorenzo in the wall, and as these piers of the third century cease exactly at the point where the conduit of that period would naturally turn off, there seems every probability that this was the Aqua Alexandrina, which was merely a branch from the Claudia and Anio Novus united to supply these thermæ, just as the Aqua Antoniniana was a branch from the Marcia to supply the thermæ of Antoninus Caracalla.

The specus of this branch was carried over the Julia on the Marcian arcade to the point where it terminates, which is exactly in a line with a lofty piscina and castellum aquæ, now a gardener’s house, between the wall and the Minerva Medica, and there are remains of the tall arcade from one to the other; the last pier which joins to that building looks like a large tall buttress to it.

The Temple of Minerva Medica is a brick building of the third century, agreeing with the time of Alexander Severus, and there has evidently been a fountain of importance in the middle of it, with an aqueduct to carry water to it from the large castellum near to it. Upon this castellum aquæ a villa of the sixteenth century has been built; but the vaulted chambers, with the tartar deposit of water, remain in the lower part of this building, and there is a tomb or columbarium of the third century at one end of it.

The dedication of a temple to Minerva Medica, in connection with an aqueduct, is natural, and that this was not an isolated example is shewn by an inscription found near Subiaco[189], and published in 1830 by Martelli, in his work on the Antiquities of Sicily[190]. The Regionary catalogue of the fourth century gives, in the fifth Regio, which contains the Esquiliæ, the Nymphæum of Alexander and the Minerva Medica, all which agrees with the existing remains of this Nymphæum. In the same vineyard, to the north-west or opposite side of the Minerva Medica, and very near to it, are the ruins of another building, called by some “a nymphæum,” now also a gardener’s house, under which the marble pavement remains very evident, the construction belonging to the period of Alexander Severus[191].

Both the Pantheum or hall for the men, and the Nymphæum or hall for the women, had images in the niches round them, and frequently an altar also, so that they were temples at the same time that they were used as waiting-rooms for the baths. The Pantheum of Agrippa was the entrance to his thermæ[192]; the building usually called the Temple of Minerva Medica, from an image found there, is called in the Regionary Catalogue Minerva Medica only. A Nymphæum and a Pantheum equally required a castellum aquæ to supply it with water for the fountains and the stream that ran round it, and there are remains of bath-chambers and niches outside of many of the larger reservoirs, as in this instance.

During some extensive excavations, which were carried on in the spring of 1871 by a company, with a view to building new streets in the eastern part of Rome, considerable remains of the lower part of the walls of these great thermæ of the third century were found on both sides of the road made in the sixteenth century, from S. Maria Maggiore to S. Croce. The company bought two large vineyards, in one of which stands the fine ruin called Minerva Medica, which was evidently one of the halls of the thermæ; the ground is full of ancient reservoirs for water at different levels, some underground, others at a considerable elevation, turned into houses; they may be traced at intervals all along the line within the Wall of Aurelian, from the Porta Maggiore to the Porta S. Lorenzo, which is itself here built against the Marcian arcade, and in one part the outer wall of the large piscina and castellum aquæ of the Tepula is incorporated with the wall, of which it now forms part. This ground had been at one period the Esquiliæ or great burial-ground, and afterwards the garden of Mæcenas, so that remains of great works for the supply of water at different periods were likely to be found there, as was the case.

XVI. The Algentiana, A.D. 300.

This aqueduct is said by some to be only a branch from the Aqua Marcia from the castellum or piscina at the Porta S. Lorenzo, to the Thermæ of Diocletian, and to have been made by him. Considerable remains of the large piscina for these Thermæ were found when the railway station was built, a plan and section of it was preserved by Visconti; it was not destroyed, but was built over and effectually hidden. The aqueduct was continued, A.D. 330, by Constantine to his Thermæ on the Quirinal, now in the Colonna gardens. Others say that the Algentiana comes from the Mount Algidus, near Tusculum. In the Campagna between Frascati and Rome, there are remains of large reservoirs or castella aquarum of the third century, which do not appear to belong to any of the aqueducts hitherto described. They are usually said to be only reservoirs for the supply of the adjacent fields; but they are all on the highest points, and it is difficult to see how the water was conveyed to them. There appears to be a regular line of them, not indeed a straight line, (the nature of the country would not admit of that,) but still a line of them at comparatively short intervals, always within sight of one another. It seems probable that the Aqua Algentiana was brought in a subterranean channel or specus from the great reservoir at Tusculum, which is on very high ground, and that the water was permitted to run into these reservoirs at frequent intervals, instead of being carried on an arcade across the country, as had been done in the case of the earlier aqueducts. It is beyond dispute that the ancient Romans were well acquainted with the principle of the syphon, and that they were quite aware that water will rise to its level after a very considerable distance: they may have therefore thought it expedient in this aqueduct to avail themselves of that principle. It is difficult to explain how water could be supplied to these numerous high reservoirs in any other manner.