the Cœlian was made in the time of Trajan, to carry water to supply the
thermæ on the Aventine, called after Sura, the cousin of the Emperor;
these thermæ were closely connected with the private house of his family,
rebuilt in his time, and called in the Regionary Catalogue “Privata
Trajani,” of which there are considerable remains, now subterranean. The
first place where this branch of the aqueduct is visible is in another
reservoir (1147) against the cliff of the Cœlian, opposite to S. Balbina.
This is partly above the level of the hill, and has been thought part of
the Palace of Commodus, on the Cœlian (which may possibly have been built
over it, but the existing remains are of the time of Trajan). The lower
part is under this, and is excavated in the cliff. These were brought to
light in the excavations of A.D. 1868 (559, 1008, 1009, 1010, 1011). The
plan and section of it are to be seen in 1150*, 692*. Against the cliff
the aqueduct formed one of the usual angles towards the north, and this
was carried across the valley on the _agger_ or bank of Servius Tullius,
first passing over the arch of the gate of the Porta Capena, above the
Aqua Appia, on a much higher level, and on an arcade, probably a double
arcade, like the Arches of Nero near the Porta Maggiore, on account of
the great height at which the water had to be carried from one hill to
the other. All that remains of this lofty arcade is a line of brick piers
passing across from the Cœlian to the Aventine, over the Aqua Appia,
before described, and passing by the north end of the Piscina Publica,
as rebuilt in the time of Trajan over the old one, which had belonged to
the older aqueducts. There are considerable remains of the walls of this
period, that divided the chambers shewn in 557, 558, 1288.
This arcade can then be traced against the cliff of the Pseudo-Aventine,
on the north side of S. Balbina, though partly concealed by the filling
up of the space against the cliff before mentioned. The tall arcade
then crosses the valley from the Pseudo-Aventine to the other part of
the Aventine, and from the garden of S. Balbina to that of S. Prisca,
and, in the latter garden, there are considerable remains of it on the
cliff opposite to the Palatine. At the north end is the _specus_ upon
the arcade (the top is open, and there is a walk upon it), 79. A small
portion of the Thermæ of Sura is also shewn, with the _specus_ in front
of the ancient wall of tufa, called the Wall of the Latins (833).
From the _piscina_ and reservoir on the cliff of the Cœlian another
branch went to the south, over the spring of the Camenæ (?) 692, and near
that of Egeria (?); it was carried over the Porta Metronia, and on the
bank of the City Wall as far as the Porta Latina.
Another fine arcade of the time of Nero (No. 1317) leads to the Nymphæum
before mentioned, where the Trophies of Marius were hung. The elevation
shews that this water must have come from the highest of the aqueducts,
the Anio Novus; and the remains of the reservoir near the Porta di S.
Lorenzo, supposed to have been for the Aqua Julia, being on high ground,
may have been for this branch, which conveyed water to the Thermæ of
Titus.
X. SABATINA TRAJANA.
Great works for the aqueducts were carried on in the time of Trajan. One
great work of his time was to bring water from the lake Sabatina to the
top of the Janiculum. Augustus had previously brought water from that
lake, supplementary to his aqueduct, from the lake Alseatina (VII.), to
supply his Naumachia in the Trastevere; but the Aqueduct of Augustus was
on the lowest level, that of Trajan on the highest. It does not appear
that Trajan made use of the old _specus_ of Augustus; but his aqueduct
was afterwards made use of by the engineers of Pope Paul V. for the Aqua
Paola, although they also brought a branch to it from the Alseatina, as
Augustus had done.
That of Trajan is chiefly subterranean, and has been described under the
head of the Alseatina (VII.), but nearer Rome it is above ground, and is
carried on an arcade against the wall of the Villa Pamphili-Doria, near
the Porta di S. Pancratio. Both the arcade and the _specus_ are faced
with the _opus reticulatum_ of that period. (664* is from a drawing, 1065
from nature.) In some parts, one side of the _specus_ has been cut away
(1063). Just on the outside of that garden a large _castellum aquæ_ of
this aqueduct has been made into a farm-house, and in the yard of that
house a branch from it can be seen (665*), apparently for the purpose of
irrigation; or, as some think, this was formerly the point of division,
one branch going to the Vatican, the other to the great fountain on the
Janiculum (960), above S. Pietro in Montorio. The division now takes
place at a short distance from this point. Procopius, writing in the
sixth century, admires the enormous quantity of water brought by this
aqueduct to the highest point in Rome; as it descends the hill, it turns
the wheels of the flour-mills. After it arrived at the low level of the
ground in the Trastevere, the respirators of the pipes for this aqueduct
are carried in tall pyramids resembling chimneys (540). Part of the
arcade and _specus_ rebuilt by Paul V., near the garden before mentioned,
is shewn in 1064, with the inscription of A.D. 1609 above it.
XI. HADRIANA (?), TRAJANA (?) OR ALEXANDRINA (?).
The next great work of the period of Trajan or of Hadrian, on the eastern
side of Rome, was probably begun in the time of Trajan. It brought water
from springs under Labicum, now La Colonna, the same that is now brought
for the Aqua Felice. The water from several springs was collected in a
central reservoir, on which an inscription of Hadrian was found by E. Q.
Visconti in the eighteenth century. This is between Pantana and Gabii, in
the valley under La Colonna (1540). There are several other reservoirs of
the time of Trajan or Hadrian along the line (1637, 1638). This aqueduct
was considered by Fabretti to be of the time of Alexander Severus, and
since his time it has usually been called the Aqua Alexandrina. It may
have been partly rebuilt and brought into use again in his time, after
having been choked up with stalactite, one of the springs used proving to
be a petrifying spring.
Near the sources this arcade is low and much damaged, and the _specus_
where it remains is nearly filled up with stalactite (1541, 1542).
In some parts of the line the stalactite has all the appearance of a
petrified cascade, and is evidently formed by the water oozing out and
dripping and petrifying as it fell (1436). Further on there is a fine
arcade for it across the country in the direction of Cento-Celle; and in
some places the arcade is double to raise the _specus_ to the necessary
level, as in the Arches of Nero (1428, 1429). A portion of the arcade,
where it is broken off, is seen in 1427, with the tower of Cento-Celle in
the distance. Another portion of this fine arcade is shewn in 1640. It
is of two periods; the upper part is of the third century, and may have
been rebuilt by Alexander Severus (as has been said). At Cento-Celle the
ground is high, and the aqueduct passes underground for some distance,
along the side of the road towards Rome.
About a mile nearer to Rome, there is a branch aqueduct from the foot of
the Marcian arcade, in the direction of the Mausoleum of S. Helena, which
Fabretti considers as part of the same aqueduct; but it is difficult
to see upon what grounds. There is a fine arcade here also for about a
quarter of a mile; but it is of the time of Constantine, and I have not
been able to trace any connection between this and the other. This arcade
has been originally double, and the lower one only now remains, with
a modern _specus_ made upon it (555 and 556); but the water now flows
_from_ the Marrana, at the foot of the arcade of the great aqueducts,
which were here on higher ground, and _runs down_ upon this arcade to the
garden and small monastery of S. Peter and Marcellinus, at the Mausoleum
of S. Helena, called the Torre Pignattara, from the earthenware pots of
which the vault was made.
XII. AURELIA, A.D. 185, AND XIII. SEVERIANA, A.D. 190.
These two aqueducts were made to convey water to the Thermæ of Commodus
and Severus in Regio I., of which the remains were found in the
excavations of 1870, just within the Porta Latina. The first part was
originally made by Marcus Aurelius, for the use of his great villa on
the Via Appia, called the Villa dei Quintilii, and the great reservoir
and thermæ connected with it remain (2346, 2349, 2350, 2351, 2352).
From thence it was brought into Rome by his successor, Ælius Aurelius
Commodus. The water came from the Alban hills, near Marino (2358, 2359,
2360, 2361, 2362, 2363), at first underground, and then on an arcade,
of which there are considerable remains near the Torre di Mezza Via di
Albano (1626 and 1627).
From the Villa dei Quintilii it went parallel to the Via Appia. One of
the reservoirs of it nearer to Rome is made into a farm-house, with a
tower to it, and has the appearance of a church at a little distance;
it is called the Casale di S. Maria Nuova (2348); it then passed again
underground. Near the head of the valley of the Caffarella there remains
a _piscina_ for it nearly perfect (1372); this is very near also to the
Circus of Maxentius and his son Romulus. There is another _piscina_ or
small reservoir for it near the church of S. Urbano, often mistaken for
a tomb; here it again forms an angle, and the _specus_ descends (plan
and drawing, 831*) to the Nymphæum, or so-called Fountain of Egeria
(262). The _specus_ is then continued in the cliff of the valley of the
Caffarella, from that fountain towards the tomb of the first century
called Dio Ridicolo. Nearly opposite to that tomb the _specus_ is visible
in the cliff, with large openings into it, between which it passes
underground. Wherever it was above ground it has been carried off as
building materials and destroyed, so that it has not again been found
until it arrives at the remains of a _piscina_, just to the south of the
Porta Latina (984). It then entered the city of Aurelian through the bank
on which his wall is built, and supplied the Thermæ of Commodus within
that gate (as has been said), 1485, 1486.
XIV. ANTONINIANA, A.D. 215.
This aqueduct was used to supply the great Thermæ of the Antonines, now
called after Antoninus Caracalla. It is more easily traced backwards,
passing along the inner side of the bank on which the Wall of Aurelian
is built, then upon an arcade which has been destroyed in this part, but
of which remains are visible inside of the Porta Ardeatina (986), by the
side of the Arch of Drusus, just within the Porta di S. Sebastiano (73,
1772, 1202). It then passes underground through the bank, and emerges in
the city wall at the angle between the Porta di S. Sebastiano and the
Porta Latina (539, 883). It here crosses the road, and is visible in the
garden on the opposite side (884).
XV. ALEXANDRINA, A.D. 225.
The Aqua Alexandrina is mentioned by Lampridius in his life of Alexander
Severus, but it was probably a branch from the Anio Novus only, as the
Nymphæum engraved on one of his coins[230] has been identified with the
ruins near S. Maria Maggiore (2126, 2127). This stands on very high
ground, and the only aqueduct that could reach it was that of the Anio
Novus. This branch can be traced in the wall by the piers of the arcade,
which have been built into the Wall of Aurelian near the Porta Maggiore
(80 A, B). The _specus_ and the arches were destroyed by the engineers of
the Aqua Felice; the piers only remain, and these cease just before we
arrive at the point where the railway now enters Rome through the wall
(99). They come to an end directly in a line with a large reservoir, now
a gardener’s house, near the Minerva Medica, almost between that and
the wall, but a little to the south of it; one pier, however, of the
tall arcade of the third century remains, as a sort of buttress, against
that side of the fine building of the same period called the Temple of
Minerva Medica (537). There are great remains of thermæ and fountains
in the large vineyard in which this building stands. Some of these are
of an earlier period; but a considerable part of them are of the third
century, and of the time of Alexander Severus. The Nymphæum before
mentioned was at the north end, and is a fine picturesque ruin, with very
evident remains of the aqueduct in it (61, 963, 964). The water was here
divided into several branches, of which we see portions of the _specus_
going in different directions. One of the most important of these goes to
the great reservoir of the Thermæ of Titus and Trajan, called the Sette
Sale. This was made long before the time of Alexander Severus, who only
rebuilt the Nymphæum; and there is an arcade of the first century leading
to this Nymphæum from a reservoir near the Porta di S. Lorenzo.
At a short distance to the south of this celebrated Nymphæum is another
very curious reservoir, now in a very bad state, having been turned into
a gardener’s house, but which must have been of considerable importance,
and probably belonged to the thermæ of the third century (2322, 2323).
There is a _cippus_ with an inscription, which indicates that the
building was a _castellum aquæ_ (2324).
XVI. ALGENTIANA, A.D. 300.
This aqueduct was made to supply the great Thermæ of Diocletian on the
Viminal Hill, but is believed to have been entirely subterranean, so that
little is known about it. There was a reservoir for it on the eastern
side of the Thermæ, under the present railway station. Drawings and a
plan of this were preserved by Visconti[231].
XVII. THE AQUA CRABRA, THE MARRANA, A.D. 1124, AND THE RIVER ALMO.
These three may all be treated as one aqueduct for the supply of Rome,
partly natural and partly artificial. They all come from the Alban
Hills; the first from near Rocca di Papa on very high ground, the second
from about a mile above the small and very picturesque town of Marino;
the third lower down the same hill. They are all mountain streams, and
partake of the usual character of such streams; in dry weather the
springs that supply the Almo bring so little water, that it is only
sufficient to fill some ponds for cattle at the foot of the hill. The
deep bed of the river, which winds about the Campagna for miles, is
therefore dry for a great part of the year, but the other two streams
never fail; they are united at the foot of the hill, not far from the
place where the Aqua Aurelia came from. The greater part of their united
waters runs into the river Anio, but a portion of it is diverted near
the ruins of the ancient fortified village or _pagus_, called _Centroni_
(2315, 2316, 2317, 2318, 2319), on the road to Tusculum, (now Frascati,)
about eight miles from Rome. This branch to supply Rome is first brought
through an ancient tunnel of the Aqua Julia, at each end of which remains
can be seen of the stone _specus_ and the flood-gates (2310, 2311, 2312,
2313). The water is then conveyed in a bank of clay for about a mile, and
then in the bed of one of the many branches of the mountain stream called
the river Almo, and so brought into Rome (1309, 1318), under the Porta
Metronia, which is built upon a bridge over it. The stream passes under
some other bridges with mills upon them, and eventually falls into the
Tiber through an aperture left for it in the Pulchrum Littus, or fine
tufa wall of the Kings (drawing, 1235*; plans, 368*, 1234*; views, 77,
166, 157).
Another branch from it is carried from the junction or separation between
the Torre Fiscale and Roma Vecchia (1937*) by the side of the cross road
from the Via Appia Nova to the Via Appia Antiqua. Sometimes in the bed
of the Almo, and in other parts, where the ground is low and the stream
is liable to floods, an artificial canal is made for it, which may be
seen in the valley of the Caffarella. This excellent plan was carried out
in the most economical but effectual manner by a company in the twelfth
century. This is really an aqueduct, though not usually so called; it is
kept in repair by the present Water-Company, and is of great importance
for Rome; as the floods to which the Almo was always liable along its
whole line, and within the walls of Rome, (as is mentioned by Cicero,)
are effectually kept out of Rome, and a constant, regular supply of water
is obtained.
XVIII. AQUA FELICE, made A.D. 1587 by Pope Sixtus V. (Felice Peretti).
The sources of it are the springs under the hill on which La Colonna
stands. The same water had been used long before, and brought into Rome
by the aqueduct (XI.) of Hadrian and Trajan before mentioned. The large
reservoir for the water now in use is very near to the remains of the old
one of Hadrian. The construction of this aqueduct is very rude and rough,
of concrete and rubble-stone only, and this stone consists entirely of
old materials; still the large scale of the work, and the height at which
the _specus_ is carried upon the arcade, give it a grand effect. At a
little distance, the inferior construction is not seen, and this almost
modern aqueduct is frequently mistaken by strangers for one of the old
ones of the time of the Empire, of which it is only an imitation. It is
seen in several of the views of the older aqueducts in the Campagna,
especially those at the Torre Fiscale (531, 1028, 1029) and the Porta
Furba (68, 1437). Here it crosses the road to Frascati on an arch, with
an inscription upon it. In the latter part of its course it is made on
the piers of the Claudian arcade, and it enters Rome at the same point,
the north-east corner of the gardens of S. Croce. After passing along the
north side of them, it is divided into different branches by a reservoir
at the angle, close to the south side of the Porta Maggiore (30). The
principal stream then passes along upon the Wall of Aurelian (80 A, B,
81), on the same high bank as the earlier aqueducts had done; it was cut
through in making the railway, but a new bridge over that road was built
for it (29). Near this it can be seen that it is carried on the piers of
an older aqueduct for some distance (28). See Alexandrina (XV.)
Further on towards the Porta di S. Lorenzo the ground is higher, and
in order to keep the level necessary for the _specus_, it is brought
within the wall, and built up against the inside of it (1871). The
Marcia, Tepula, and Julia, over which it is carried, as is seen at the
two gates where their arcade is visible _under_ the _specus_ of the Aqua
Felice, are here still under it, but _underground_ also, owing to the
higher level of the ground. It passes over the Porta di S. Lorenzo to a
reservoir on the north side of it, and then turns to the west by the side
of the road, which it crosses upon an arch, with an inscription upon it,
at a short distance within that gate (81). The principal termination of
it is at the Fountain of the Termini (called of Moses,) 71. Behind the
fountain is a reservoir after the old fashion, which is illustrated by a
plan and section (704*). The celebrated Fountain of the Triton (1196),
in the Piazza Barberini, is also supplied by this aqueduct, as well as
all the upper terraces upon the hills. The lower range, on the Campus
Martius, is chiefly supplied by the Virgo. Another branch goes from the
reservoir at the Porta Maggiore along the bank on which the Arches of
Nero are carried, to the Lateran, where the fountains are supplied by
this water. The old aqueduct was used according to the custom of the
time, and there is a cascade _specus_ from the level of the Marcia to
that of the Appia (shewn in 541).
The _specus_ of each of these old aqueducts was used to carry the metal
pipes of the Aqua Felice, when it was convenient to do so (1295*), as has
been previously mentioned.
THE AQUA MARCIA PIA was made by a Company between 1860 and 1870, and has
been mentioned under the head of the Marcia (a part of it is shewn in
1553).
THE AQUEDUCTS.
ANIO NOVUS.—THE RIVER ANIO.
DESCRIPTION OF THE PHOTO-ENGRAVINGS.
PLATE I.
[Illustration: AQUEDUCTS—SOURCE OF AQUA APPIA.
ANCIENT QUARRY OF THE KINGS.]
Source of the Aqua Appia, in a very ancient Stone-quarry of the time of
the Kings, in the meadows on the bank of the river Anio, formerly called
the meadows of Lucullus. They are not far from Lunghezza, the site of
the ancient city of Collatium. This cave has two springs of water in it,
and the two streams meet at the mouth of the cave in a channel, which is
at first open at the top, and crosses the low meadow with the appearance
of a ditch only, to a central reservoir, also in a cave, from which the
tunnel _specus_ begins that runs on, into and through Rome. Three streams
meet at the same central reservoir, and their united water goes through
the _specus_. Each _specus_ can be traced by the line of bushes in the
meadows, each bush being over one of the wells; these descend at regular
intervals into the _specus_. These wells are also called respirators or
ventilators, as they give air to the current of water, or as the people
say, enable it to breathe. This cave is easily overlooked, and any person
passing on the higher ground over it, is almost sure not to see it. It
is scarcely visible until close to it. The ancient quarry from which it
comes is earlier than others in the neighbourhood. The celebrated Caves
of Cervaro are also ancient quarries; they are about a mile from this
point, and although very early, are not quite so early as this, which is
more distant from the river Anio. It seems probable that this was one
of the quarries for the city of Collatium, before the time of Servius
Tullius.
PLATE II.
[Illustration: AQUEDUCTS—SOURCE OF AQUA APPIA.
ANCIENT QUARRY OF THE KINGS.]
SOURCE OF ANOTHER SPRING OF THE AQUA APPIA, in another ancient stone
quarry on the bank of the river Anio. This is one of a fine series of
ancient quarries, now caves, about a mile higher up the river than the
Caves of Cervaro. These are believed to have been the quarries from
which the large blocks of tufa for the walls of the Kings of Rome were
taken, especially the great wall of Servius Tullius, which was a mile
long, fifty feet high, and in some parts twelve feet thick, and which
would require an enormous quantity of stone. This was probably floated
down the Anio on wooden rafts, which served for timber also. The pool at
the source of this spring appears as if it came from the water dripping
through the rock above, which serves for a roof; but the old shepherds,
who have watched it for years, say that the water never fails, and that
it is a natural spring, although the quantity of stone refuse thrown into
it makes it impossible to see exactly where it rises. These caves are
extremely picturesque, more so even than the Caves of Cervaro, though
these are the favourite resort of the German artists in their annual
festival.
PLATE III.
1. THE AQUEDUCTS ABOVE SUBIACO.
2. RIVER ANIO, THE UPPER LOCHS.
—— THE THIRD LOCH AND THE BRIDGE.
[Illustration: AQUEDUCTS ABOVE SUBIACO
RIVER ANIO THE UPPER LOCHS
THE THIRD LOCH AND THE BRIDGE]
The water for the aqueducts of Rome was chiefly drawn from the river
Anio, or from springs or tributary streams that fell into that river. It
rises in the high mountains above Subiaco, which are generally covered
with snow for the greater part of the year, and the supply of water never
fails entirely, though it is not always equally abundant. It is generally
a clear, bright mountain stream, coming through rocks, but it is liable
to sudden and violent floods, which bring down a great deal of mud, and
therefore great precautions are taken for filtering it. The latest and
most important of the great aqueducts were the Claudia and Anio Novus;
the latter was the most abundant of all, being in fact a branch of the
river compelled to pass through Rome by clever engineering. A series of
great lochs was made by building dams across the river, with cascades
from one to another. There were three of these about two miles above
Subiaco, and about forty-two miles from Rome. The uppermost one of them
is seen in the upper part of the plate, but in the third loch, the lowest
of the three (shewn in the lower part of the plate), the bed of the river
is so deep, that the water is not seen. The country through which it
passes is celebrated as among the most beautiful in Italy.
PLATE IV.
[Illustration: AQUEDUCTS ABOVE SUBIACO
ANIO NOVUS, THE THIRD LOCH
ANIO NOVUS, SPECUS CUT IN THE CLIFF]
1. ANIO NOVUS, THE THIRD LOCH, as seen from below, where the dam, that
formerly kept up the water and formed a great cascade, has been thrown
down, and appears only as rocks in the stream; the modern bridge seen in
this view is built upon the two ends of the old dam.
2. ANIO NOVUS, SPECUS. The _specus_ is here a tunnel cut in the cliff,
on the side of the valley on which the town of Subiaco stands; it is six
feet high, and only eighteen inches wide (an opening into it may be seen
in the cliff, on the left-hand side of the view). The round tower, seen
on the right, is that of the Villa Gori, about a mile above Subiaco.
PLATE V.
AQUEDUCTS ABOVE SUBIACO—ANIO NOVUS, CASTELLUM.
[Illustration: AQUEDUCTS ABOVE SUBIACO
ANIO NOVUS, CASTELLUM
LINE OF THE SPECUS OF ANIO NOVUS
_Photogravure Dujardin, Paris_]
This is the loch below the modern bridge, which is made upon the remains
of the old dam across the river, destroyed in the fourteenth century by
making a hole at the bottom to let the water escape from a flood in the
upper country. The force of the water once let loose soon destroyed the
dam, and the large stones of which it was built are still lying as rocks
in the river, and are seen in the photograph and the photo-engraving.