PART VIII.
THE AQUEDUCTS.
THE
ARCHÆOLOGY OF ROME,
BY
JOHN HENRY PARKER, C.B.
HON. M.A. OXON., F.S.A. LOND.;
KEEPER OF THE ASHMOLEAN MUSEUM OF HISTORY AND ARCHÆOLOGY, OXFORD;
VICE-PRESIDENT OF THE OXFORD ARCHITECTURAL AND HISTORICAL SOCIETY,
AND OF THE BRITISH AND AMERICAN ARCHÆOLOGICAL SOCIETY OF ROME;
MEMBER OF THE ROYAL ARCHÆOLOGICAL INSTITUTE,
MEMBRE DE LA SOCIETÉ FRANÇAISE D’ARCHÉOLOGIE,
HONORARY MEMBER OF THE ROYAL INSTITUTE OF BRITISH ARCHITECTS,
AND OF VARIOUS ARCHÆOLOGICAL SOCIETIES, ENGLISH AND FOREIGN.
THE AQUEDUCTS.
=OXFORD:=
JAMES PARKER AND CO.
=LONDON:=
JOHN MURRAY, ALBEMARLE-STREET.
1876.
[Illustration]
THE AQUEDUCTS.
PREFACE TO THE AQUEDUCTS.
It is impossible to understand the archæology of Rome without studying
the Aqueducts. In every part of the City, and of the country round it,
there are remains of them; they are frequently mistaken for something
else, and called by other names, misleading those who have not given
attention to the subject. They are necessarily mixed up with the
_Thermæ_, for most of the aqueducts were made to bring water to those
great establishments. There was also a reservoir of water supplied by
the aqueducts under each of the palaces, larger houses and villas, as
may be seen in many parts of the Palatine, under the palaces of the
Cæsars. In their original state the Aqueducts must have been among the
grandest objects in Rome, and the most conspicuous in all directions.
The principal approach from the east passed between two fine arcades of
the aqueducts, one carrying three of them, the other two. These two fine
arcades were not more than a hundred yards apart; all the great roads
from the eastern side were brought into this space, and certainly, for
the last mile into Rome, must have had one of these arcades on either
hand: to the left, or south, the Claudian arcade, fifty feet high; to the
right, the Marcian, thirty feet high.
For the last half-mile, the Claudian arcade was also the boundary of
the palace gardens of the Sessorium, the residence first of the Kings
and afterwards of one branch of the imperial family (that of Verus or
Varius), who resided there for more than a century. That portion of the
arcade still exists for a considerable extent, forming the northern
wall of that garden, and at the same time part of the wall of the city,
Aurelian having adopted it, and incorporated it with his great wall. This
portion is thoroughly shewn in my Photographs, as it is a very important
part of the antiquities of Rome, and illustrates many points. It was the
place where the principal aqueducts entered Rome, and the whole ground
is full of remains of them with their reservoirs and filtering-places.
The inner side of the wall is the part necessarily shewn, because the
outer side is concealed by the arcade of the Aqua Felice, excepting
in places where the _specus_ of the Claudia and the Anio Novus appear
above it. Just outside of this garden, at the west end of it, is the
great foss which separated the Sessorium, or fortified palace, from
the other fortifications of the City, and in it are remains of the two
great reservoirs that were probably the Gemelli or Twins of Frontinus,
made originally for the Appia and the Anio Vetus side by side, and used
afterwards to receive the surplus water of the later aqueducts on a
higher level. We then have a considerable number of the Arches of Nero,
following a straight line for another mile to the west end of the Cœlian
Hill; where remains of the great reservoir are on a level with the
_specus_ carried on the top of this arcade, fifty feet above the ground
in that high situation, from which the water was distributed in all
directions, first on other arcades, three of which branched off from this
point, and afterwards in metal pipes when it was sub-divided; but for the
main supply no metal pipes then to be had were large and strong enough to
bear the pressure of a stream of water four feet deep and two feet wide,
running at the rate of five or six miles an hour, if not more. The direct
line went on over the Palatine to the Capitol, passing over the Forum
Romanum on the bridge of Caligula, of which, also, some remains are shewn
in my Photographs; the other two branches from the great reservoir over
the Arch of Dolabella, went one to the right to the Colosseum (to supply
the Stagna there), the other to the left to the Aventine, to supply the
private house of Trajan and the Thermæ of Sura.
The Porta Maggiore stood at the end of the long vista between the two
great aqueducts, and was itself made out of two of the arches of the
Claudian arcade, in the last of the angles that occurred at every
half-mile. The penultimate one was at the eastern end of the Sessorium
palace gardens, where this water entered Rome, and then, after passing
the angle to the north, with the usual _piscina_ and _castellum aquæ_,
or reservoir and filtering-place, turned again to the west, as far as
that gate where the Claudian arcade terminated. From this point the
Marcian turned to the north upon the great bank of earth which formed the
outer defence of Rome in that part, and continued along it for another
half-mile, as far as the Porta di S. Lorenzo, and beyond it to the
Prætorian Camp; then turning again to the west, it went across the great
inner foss between the outer bank, the great _agger_ of Servius Tullius,
which formed the inner line, where remains of it were found near the
railway station in 1871, with inscriptions on two of the _cippi_, stating
that the three aqueducts passed there. It is not quite correct to say
that the _arcades_ were carried there, because where the ground is high
the _specus_ are carried underground. This is the case between the Porta
Maggiore (the Porta Esquilina of Frontinus) and the Porta di S. Lorenzo
(the Porta Viminalis of the same). The _specus_ is seen on arches close
to each of the gates; but, between the two, it passed underground through
a sort of hillock, about midway between the two gates, as is mentioned
by Frontinus. The ground is high again near the Porta Chiusa at the
Prætorian Camp, and in the great bank or _agger_ of Servius Tullius.
These two great arcades are those chiefly known to visitors to Rome
as THE AQUEDUCTS; but the underground aqueducts are at least equally
interesting when understood. The Anio Vetus being near the surface can be
traced all over Rome; the Appia being very deep, is not so easily traced,
and can only be seen with certainty near its source and its mouth. There
are other arcades nearly as fine as these; but, as they do not come so
near Rome, they are less known; in the parts nearest to the City they are
either underground or destroyed. One of them is that called Alexandrina
by Fabretti; but the original parts of it are of the time of Hadrian and
Trajan. This runs from the source near Gabii and Labicum, now la Colonna,
to the place called _Cento-Celle_. Possibly some of the hundred cells
or vaults found there and supposed to have been all tombs, were really
reservoirs of water. At every great villa there are always remains of
these great cisterns for the supply of water, and this is about three
miles from Rome, where a great villa of Hadrian was situated. This arcade
extends for miles across the country between the two great roads, one
from Gabii, the other from Preneste (now Palestrina). Another fine arcade
is seen on the road to Albano, at the Tor di Mezza Via (or half-way
house). This has been ascertained to be the Aqua Aurelia, which goes to
the villa of the Quintilii on the Via Appia, and from thence into Rome
to supply the Thermæ of Commodus and Severus, of which also remains have
been found; the latter part of its course is chiefly underground.
It was very difficult at first to ascertain to which of the aqueducts
each of the remains belonged that were seen on all sides; and I found
it necessary to follow each aqueduct up to its source, and then down
to its mouth, in order to ascertain this. This work has taken me some
years, in connection with the other branches of the general subject of
the Archæology of Rome. It has now been done, with one exception,—the
aqueduct made to bring water to the Thermæ of Diocletian on the
Viminal,—which has not been traced; but there is great probability that
it was a branch from one of the older aqueducts, probably brought across
from the great reservoir where the Nymphæum of Alexander Severus was
situated, on which the Trophies of Marius were hung. This is on high
ground, and at a short distance only, so that it would be very convenient
for the purpose. We see that there are several branches from that point,
and one of them probably supplied these great Thermæ, for which purpose
more than one aqueduct would be tapped. It may be that the curious sort
of tower reservoir—long supposed to have been a tomb, a short distance
to the south of the Trophies of Marius—was the one for these Thermæ; in
either case, these reservoirs were supplied from the great old aqueducts.
I may almost say that wherever the aqueducts are visible, they can now
be seen in my Photographs, and in some places the remains have been
destroyed since these were taken, during what is called the _Restoration_
of the City Walls. Perhaps the finest and most interesting part of
the Aqueducts are the great cascades at the source of the Anio Novus
above Subiaco, in the bed of that river, situated in some of the finest
scenery in the world. Among later works the ingenious manner in which
the bed of the small river Almo is made use of to carry the water of
two other mountain streams, the Aqua Crabra and the Marrana, the water
of which never fails; and the manner in which the tunnel of the Aqua
Julia has been used again in the twelfth century, are the most curious
and interesting. This had hitherto escaped observation, and was not
easily traced. The Aqua Felice was unfortunately carried out in a very
rude manner; the plan of the Pope was a good one, but was spoiled by the
ignorance of the engineer.
The new aqueduct, the Aqua Marcia-Pia, restoring the celebrated Aqua
Marcia to use in Rome, is a work deserving of high commendation. It is
much to be regretted that my lamented friend the late Mr. Shepherd, to
whose energy and perseverance we are chiefly indebted for this, did not
live to see the completion of his work. Much credit is also due to Signor
Moraldi, the originator of the scheme, to whom the Company still pay a
premium, which he well deserves. His map[1] of the Aqua Marcia, of which
he kindly gave me a photograph, was of great service to me, as far as
it went; but I saw it was necessary to go further, and include all the
Aqueducts on the eastern side of Rome. I was fortunate in meeting with
Dr. Fabio Gori, who is a native of Subiaco, and has been interested in
the Aqueducts from his boyhood. He shewed me that Signor Moraldi had not
gone quite far enough, and that the real spring of the Marcia is about
a mile further from Rome than the one he supposed to be so, which was a
subsidiary spring, though of equally good water. At the original source
the stone _specus_ was found, having been long concealed by being a foot
or two under water. I saw it, and stood upon it, and had a photograph
made, so that there could be no mistake, and the engineer of the company
also saw it, and carried his aqueduct to that point; so that the real
ancient Aqua Marcia now comes into Rome again, and is getting rapidly
into general use, being much the best drinking water. The water supply
of ancient Rome has long been a subject of interest, and can now be more
perfectly understood than it ever could before. The series of Photographs
of them are a thorough illustration of their history, such as could not
have been made before that art was invented.
CONTENTS OF THE AQUEDUCTS.
PAGE
PREFACE iii
Introduction—Frontinus 1
I. AQUA APPIA.
Passages from Frontinus 3
Sources in the Lucullan fields 4
—— near the old Via Prænestina 5
The course underground 6
It entered Rome at the north-east end of the Sessorium ib.
—— passed along the Cœlian Hill ib.
Reservoir in the garden of the Villa Cœlimontana, now the Arch
of Dolabella 7
It crossed the valley to the Aventine on an ancient earthwork,
near the Porta Capena 8
to the Piscina Publica 9
Under the Aventine the _Specus_ is visible in a stone quarry
nearly under S. Sabba ib.
Wells to descend into it ib.
The branch added by Augustus entered Rome in the garden of the
Sessorium 11
—— near the Gemelli ib.
Torquatian and Pallantian gardens ib.
II. ANIO VETUS.
Passages from Frontinus 13
Sources—a branch from the river Anio ib.
_Specus_ in the cliff of the valley 14
—— visible in the “Valley of the Arches” above Tivoli ib.
—— and in the promenade of Carciano below it 15
—— Its course underground 16
Piscinæ at the fourth, and at the second, mile from Rome, on
the Via Latina ib.
Crossing of the Aqueducts at the Torre Fiscale 17
Castellum Aquæ near the Porta Furba, two miles from Rome 18
—— near the Via Appia Nova ib.
The _Specus_ faced with _Opus Reticulatum_ 19
_Specus_, or _spes_ (?) _vetus_, on the high banks ib.
Another branch on the bank near the Wall of Rome 20
And another branch along the Cœlian, and passing near the Port
Capena, to the Aventine 21
Appendix, _Spē_ or _Spc̄_, _Spes_ (?) or _Specus_ (?) 22
—— Facsimile from MS. at Monte Cassino 26
Passages relating to the word _Specus_ 27-31
III. AQUA MARCIA.
Passages from Frontinus 32
The Piscinæ 34
Source of the Marcia ib.
_Specus_ carried along the valley of the Anio 35
Principal source in the Acqua Serena ib.
Old _Specus_ under water, discovered in 1869 36
—— It crossed the river at S. Cosimato ib.
—— and again in the Valley of the Arches, above Tivoli, on a bridge ib.
_Specus_ and reservoir in the Promenade of Carciano, below Tivoli ib.
Reservoir faced with Cyclopean Masonry there 37
_Specus_ passes near Ponte di S. Antonio ib.
After reaching the City it is divided into several branches ib.
One along the Cœlian and over the Porta Capena to the Aventine 38
Another upon the old _agger_, and over the Porta Tiburtina to the
Prætorian Camp ib.
Excellent qualities of the Aqua Marcia ib.
IV. TEPULA.
Sources near Grotta Ferrata 39
_Specus_ joins the Marcia at the _Piscinæ_ 40
—— is carried into Rome on the Marcian arcade ib.
_Castellum Aquæ_ for it near the Porta Tiburtina (S. Lorenzo) ib.
V. JULIA.
Sources on Mons Algidus (near Tusculum), Frascati, and Grotta
Ferrata 41
_Specus_ passed near the Pagus Lemonius 42
—— on an arcade of rough stone ib.
—— then through a tunnel in the valley ib.
The Nymphæum of Alexander Severus, where the Trophies of Marius
were hung, was _not_ for the Aqua Julia, though usually called
so. It is at too high a level for that, and was for the Claudia
and Anio Novus united 43
_Cippi_ of _the three_ Aqueducts, found in 1869, near the railway
station 45
Remains of a reservoir near the Porta Chiusa, found in 1869 ib.
VI. VIRGO (AQUA DI TREVI).
Passages from Frontinus 46
Sources on the Via Collatina ib.
_Specus_ subterranean, but easily traced by the line of respirators 47
—— It follows the old road towards the Porta Maggiore 48
—— but turns to the north and enters Rome through the Pincian Hill,
under the Villa Medici ib.
—— It supplies the lower town and the fountain of Trevi ib.
—— Original termination in front of the Septa, near the Pantheon ib.
VII. ALSIETINA.
Passages from Frontinus 50
Lacus Alsietina, Lago di Martignano ib.
Aqua Paola 51
Lacus Sabatina ib.
Junction of two _specus_ at the Cariæ (Osteria Nuova) 52
Casale Bianca, additional springs ib.
In Tunnels to Rome 53
VIII. CLAUDIA. IX. ANIO NOVUS.
Passages from Frontinus 54
River Anio 56
Cascades at Valle-Pietra 57
Bridge of Communacchio ib.
Sacro Speco ib.
Monasteries of S. Benedict and S. Scholastica ib.
Subiaco ib.
Lacus—Lakes or Lochs of Nero 58
Villa Sublacensis ib.
Great dam at Piè-di-lago ib.
Bridge of S. Mauro ib.
_Specus_ of the Anio Novus, cut in the rock of the cliff ib.
Ruins of _piscinæ_ 59
Lowest loch circular 60
_Piscina Limaria_, forty-two miles on the Via Sublacensis ib.
_Specus_ of Claudia 61
Bridges at Vicovaro and in the Valley of the Arches, two miles
above Tivoli ib.
Cascade at Tivoli ib.
Promenade of Carciano ib.
Bridge of S. Antonio and Ponte Lupo 62
—— near the road to Poli ib.
The _Piscinæ_ 63
_Specus_ of the Claudia of stone, of the Anio Novus of brick over
it, on a stone arcade ib.
_Piscina_ at the Porta Furba 64
Other reservoirs ib.
The Neronian Arches ib.
Porta Maggiore, inscriptions on 65
Architect of the Claudia 66
Arcade on the Cœlian ib.
Reservoir over the Arch of Dolabella 67
Three branches from that high reservoir: 1. to the Claudium and
the Colosseum; 2. to the Palatine and Capitol; 3. to the Aventine,
over the Porta Capena ib.
Smaller reservoirs for subdividing 68
Rebuildings by Frontinus under Trajan ib.
Springs called _Cæruleus_ and _Curtius_ 69
The _Piscinæ_ 70
Appendix—The Nine Aqueducts of Frontinus 71
Tables of Dates, Names, Levels, Length of Channel, Supply,
Distribution 73, 74
Calculations 74-79
The Curator Aquarum 80
Repairs by the Popes ib.
Popular notions erroneous 81
These stone _specus_ necessary for the main stream, and leaden
pipes for distribution 82
Brass cocks and leaden pipes often stolen, as mentioned in a
letter of King Theodoric ib.
X. SABATINA, TRAJANA, A.D. 110, AND PAOLA, A.D. 1540.
Lacus Sabatina, di Bracciano, or Anguillara 83
This aqueduct connected with the Alsietina (VII.) ib.
The line traced backwards by the respirators from the terminus on
the Janiculum ib.
Procopius amazed at the quantity of water brought by this aqueduct
in the sixth century ib.
Restorations of the Popes 84
Inscriptions of Paul V. ib.
Cascade on the Janiculum, turns the wheels of the flour-mills ib.
_Specus_ in the wall of the garden of the Villa Pamphili-Doria 85
—— but chiefly underground, traced by the respirators ib.
XI. TRAJANA (?), HADRIANA (?), ALEXANDRINA (?).
Passage from Frontinus 86
Sources near Gabii and Labicum, now La Colonna ib.
Several springs were collected in a central reservoir, on which
an inscription of Hadrian was found by E. Q. Visconti ib.
One of these springs had petrifying qualities ib.
Singular effects of the petrifying stream 87
_Specus_ choked up with stalactite, and cascades petrified ib.
The same water used for the Aqua Felice, but the petrifying
stream excluded 88
A fine arcade for miles, from the source to Cento-Celle ib.
Part of it of the first century, other part of the third.
Alexandrina (?) ib.
Aqueduct of Hadrian mentioned by Spartianus, but not in the
Regionary Catalogue 89
Branch from the great aqueducts to the Mausoleum of S. Helena
(Torre Pignattara) and to the Villa of the Gordiani (Torre
de’ Scavi) 90
—— not connected with this aqueduct ib.
—— but also has _piscinæ_ of the first and third centuries ib.
Branch of Trajan to the Aventine from the Cœlian ib.
XII. AURELIA, A.D. 185. XIII. SEVERIANA, A.D. 190.
The Aurelia made by Marcus Aurelius 92
—— to convey water to the Villa de Quintilii ib.
—— continued by Commodus and Septimius Severus to their _thermæ_
in Regio I. ib.
Remains of _piscinæ_ outside of the Porta Latina ib.
Remains of the _thermæ_ inside of that gate ib.
Sources on the hill of Marino 93
_Specus_ partly underground, part on arcade at the Torre di
Mezza, Via di Albano ib.
Large reservoir at the Villa de Quintilii ib.
Others on the Via Appia, between that Villa and Rome ib.
—— at the Circus of Romulus ib.
—— at S. Urbano ib.
—— at the Nymphæum in the valley of the Caffarella (miscalled
the Fountain of Egeria) ib.
_Specus_ visible in the cliff of that valley, near the Dio Ridicolo 94
Remains of the _thermæ_ in the Monte d’Oro ib.
XIV. ANTONINIANA, A.D. 215.
This aqueduct enters Rome at the south-east corner 95
—— passes over the arch of Drusus ib.
—— along the inner side of the great bank on which the Wall of
Aurelian is built ib.
—— to the _piscina_ of the Thermæ of the Antonines or of Caracalla ib.
Fine _piscina_ and _castellum_ on the edge of the hill overlooking
the valley of the Caffarella ib.
Remains of others on the Via Latina 96
—— and one near the Porta Furba, at two miles from Rome, at the
foot of the great aqueduct ib.
A branch of the Anio Vetus (?) ib.
XV. ALEXANDRINA.
This aqueduct mentioned by Lampridius 97
—— Made to bring water to the Thermæ of Alexander Severus, near
the Pantheon ib.
—— Probably a branch from the great aqueducts near the Porta
Maggiore ib.
An inscription found near that point ib.
Remains of arcade of this period between that gate and the Minerva
Medica 98
Nymphæum of Alexander Severus, where the Trophies of Marius were
hung 99
Nymphæum, a hall of the Thermæ for women; Pantheum, a similar
hall for men ib.
Wall of Aurelian built against this tall arcade ib.
XVI. ALGENTIANA.
This aqueduct made to supply water to the Thermæ of Diocletian 100
Remains of a large _piscina_ were found on the site of the
railway station ib.
The water is said to have been brought by a branch from the
Marcia at the Porta di S. Lorenzo ib.
Others say it came from Mons Algidus, near Tusculum, and was
brought underground, with reservoirs on the tops of hills
in the Campagna, supplied by syphons ib.
XVII. AQUA CRABRA AND MARRANA.
These streams united are brought into Rome in the bed of the
River Almo 101
Sources of the Aqua Crabra, near Rocca di Papa ib.
Those of the Marrana near Marino ib.
The two united at the foot of the hill of Marino 102
_Piscina_ in the valley under Marino ib.
_Specus_ traced in the same valley near the quarries of _peperino_
or _lapis Albanus_ ib.
—— passes under the sources of the Aqua Julia ib.
The two streams united near a bridge on the road to Grotta
Ferrata, ten miles from Rome ib.
Part of the united water runs into the river Anio ib.
Another part is brought through the tunnel of the Aqua Julia (V.) ib.
—— then in a cutting to the bed of the small river Almo ib.
It is carried alternately in that deep bed when the ground is
high, and in a bank of clay when the ground is low 103
The stream is divided at a loch between Roma Vecchia and the
Torre Fiscale ib.
One branch follows the line of the great aqueducts towards Rome,
in the bed of the Almo ib.
It enters Rome in that bed, under the bridge on which the Porta
Metronia stands ib.
It then passes the Garden of Crassipes, now the Orto Botanico 104
—— turning to the north, under the Aventine, to the Piscina Publica ib.
—— passes through the Circus Maximus, and under several mills ib.
—— to the mouth of the river Almo in the Tiber, through an
opening left for it in the Pulchrum Littus ib.
This Aqueduct was made under Pope Calixtus II. in A.D. 1124 ib.
Another branch of it is carried by the side of the other branch
of the river Almo, in the valley of the Caffarella, and the
other _specus_, which is open on the top, has lochs in it there 105
XVIII. AQUA FELICE, A.D. 1587.
So called after Pope Sixtus V. (Felice Peretti) 106
Source under La Colonna ib.
Reservoir made under Gregory XIII., A.D. 1572-1585 ib.
The arcade and _specus_ were made under Sixtus V., but other
reservoirs were not completed until Urban VIII., A.D. 1623-44 ib.
The _fistula Urbana_ of marble ib.
The piers and foundation of the old arcade used ib.
The _specus_ enters Rome near the Porta Maggiore 107
The water is then divided into different branches ib.
Junction of this arcade with the old one of the Claudia 108
From the Porta Maggiore the main line is carried upon the same
high bank as the old Aqueducts ib.
It turns at the Porta di S. Lorenzo 109
—— and is carried on an arcade to the great _agger_ on the
Viminal, and to the fountain of the Termini, called that of Moses ib.
SUMMARY.
Frontinus mentions _nine_ Aqueducts 110
The Regionary Catalogue of the fourth century enumerates
_nineteen_ Aquæ in Rome ib.
Some of these were natural watercourses 111
Procopius in the sixth century mentions _fourteen_ only 112
LEVELS OF THE AQUEDUCTS 113
AQUEDUCTS.—LIST OF PLATES.
PHOTO-ENGRAVINGS.
PLATE
I. Source of the Aqua Appia, in a very ancient Stone-quarry of the
time of the Kings, on the bank of the river Anio.
II. Source of another Spring of the Aqua Appia in another ancient
Stone-quarry, (near to the former).
III. 1. THE AQUEDUCTS ABOVE SUBIACO.
2. —— River Anio, the Upper Lochs.
—— —— the third Loch and the Bridge over it.
IV. 1. —— Anio Novus, the third Loch.
2. —— —— The Specus.
V. —— Anio Novus—a Castellum Aquæ, and Line of the Specus cut in the
cliff.
VI. The Claudia, Anio Vetus, and Novus, and Marcia, in the Valley of
the Arches below Subiaco and above Tivoli.
VII. Two other Views of the Ruins of the Arcades of the Claudia and
Anio Novus (in the Valley of the Arches above Tivoli).
VIII. Aqueducts at Tivoli—Cascades of the Anio, with the Round Temple
of the Sibyl at the top.
IX. Aqueducts below Tivoli—The Marcia—a great Castellum Aquæ on the
Via di Carciano, B.C. 145.
X. Aqueducts below Tivoli—Aqua Marcia—Reservoir, or Castellum Aquæ.
Views of the two chambers.
XI. Aqueducts below Tivoli—1. Anio Novus—Castellum.
2. Marcia—Castellum rebuilt by Trajan.
XII. The Claudia and Anio Novus in the Campagna of Rome, near Roma
Vecchia, over the fine arcade, four miles from Rome.
XIII. The Claudia and Anio Novus passing over the Marcia, Tepula, and
Julia, at the Tor Fiscale, and view near the Porta Furba.
XIV. 1. The Marcia on the bank within the wall of Aurelian, at the
Porta Tiburtina.
2. Claudia and Anio Novus at the angle of the Sessorium.
XV. Aqueducts at the Porta Maggiore—
1. Marcia, Tepula, and Julia, entering Rome, passing through
the Wall.
2. Marcia, &c., within the Wall.
XVI. 1. Claudia and Anio Novus over the Porta Maggiore.
2. Anio Novus on the Cœlian, over the arch of Dolabella.
XVII. 1. Arches of Nero within the Porta Maggiore, crossing the great
inner _fosse_ of the Sessorium on a double arcade.
2. Aqua Marcia within the Porta Maggiore, as shewn in an
excavation in 1871.
XVIII. 1. The Claudia and Anio Novus, in the North Wall of the Gardens
of the Sessorium, now of S. Croce.
2. Nymphæum of Alexander Severus, where the trophies of Marius
were hung.
XIX. Great Reservoir on the Arches of Nero over the Arch of Dolabella,
on the Cœlian.
PLANS AND DIAGRAMS.
PLATE
I. Plan of the Sources of the Appia and Virgo, in the meadows of
Lucullus, on the bank of the river Anio.
II. The Appia at the Porta Capena, the specus passing through one
of the towers of the Porta Capena, now a gardener’s cottage.
III. The Appia under S. Sabba. The specus in an old stone quarry on
the Pseudo-Aventine.
IV. Mouth of the Appia under the Aventine, and at the Porta Trigemina,
now in a Cave under S. Alexio and the Priorato.
V. Aqua Appia—Reservoir in Garden of the Sessorium, now of S. Croce,
called the Thermæ of S. Helena.
VI. Anio Vetus.—Reservoir near the Porta Furba.
VII. Loch in the Aqua Julia, near the Imperial Villa, called the Sette
Bassi.
VIII. Aqueducts and River Almo, near the Porta Furba.
IX. The Seven Aqueducts at the Tor Fiscale. Plan and Section.
X. Piscina of the Anio Novus, entering Rome through a tower in the
wall of Aurelian in the garden of the Sessorium.
XI. The Aqueducts at the Porta Maggiore and the Porta Tiburtina.
Plan and Section.
XII. Nymphæum, where the Trophies of Marius were hung. Plan and
Section.
XIII. River Almo—Division into two Branches, now a Loch of the Marrana.
XIV. River Almo, now the Marrana.—Entrance into Rome under the Porta
Metronia.
XV. River Almo—Mouth in the Pulchrum Littus. View.
XVI. —— Plan.
XVII. Sources of the Aqua Appia, near the bank of the river Anio, in
a very ancient stone quarry.
XVIII. Aqua Appia, or Appian Aqueduct, crossing the valley from
the Cœlian to the Aventine upon the short Agger of Servius
Tullius, and over the Porta Capena.
XIX. Plan and Sections of the Aqueducts in a Cave in the Aventine,
under S. Sabba, with the Excavations made in 1875 and 1876.
XX. Plan and Section of the Aqueducts, from the great Reservoirs on
the Cœlian Hill, near the Arch of Dolabella and the Claudium,
to the Colosseum, and to the Drain under the road from the
Arch of Constantine to the Clivus Scauri.
XXI. Sections of the Specus or Conduits of fifteen different Aqueducts.
Plan of the Aqueducts on parts of the Cœlian and the Esquiline Hills,
from the great Reservoirs and Piscinæ called Sette Sale, on the
Esquiline, to the Colosseum; and the Three Branches from the great
Reservoir on the Cœlian, and over the Arch of Dolabella, and the
Piazza della Navicella, to the Aventine, the Palatine, and the
Colosseum.
Map of the Aqueducts on the Eastern side of Rome, from their Sources
above Subiaco, and on the bank of the river Anio, to Rome, and their
mouths in the Tiber.
—— Western side of Rome, from their Sources in the lakes on the hills,
called Alseatina and Sabatina, or Anguillara.
CHAPTER IV. PART I.
THE AQUEDUCTS.
In treating of the Aqueducts we have a trustworthy guide in a writer who
flourished in the time of the Emperors Nerva and Trajan, namely, SEXTUS
JULIUS FRONTINUS[2]. While he informs us of what improvements he made
during the time he had the charge of these important public works, he
also gives in his treatise a historical account of the several changes
which had been from time to time made in the means of supply of water to
the Imperial City, which kept pace with the growing wealth and population
of Rome. When he died they had probably reached perfection, and were
justly the admiration and surprise of all travellers[3].
His treatise is well worth examination, not only from an archæological
point of view, but as suggesting also many curious enquiries as to the
engineering abilities which the Romans possessed, compared with those
exhibited at the present day. In elucidating, however, the architectural
antiquities of the city of Rome, it will be necessary, as far as
possible, to limit the extracts from his treatise _De Aquæductibus_, to
those portions which refer either directly to existing remains, or which
indirectly explain them, by pointing out the principle on which the
several Roman aqueducts seem to have succeeded each other.
Frontinus tells us in his fourth chapter, that for 441 years after the
building of the city, or until B.C. 312, the people were content with
the water which they could draw from the Tiber, or from wells[4] or from
springs, of some of which the memory was in his time still held sacred
and honoured, for they were thought to afford health to the sick[5].
Passing to his own time, he says, “there now flow into the city:”—
I. Aqua Appia.
II. Anio Vetus.
III. Aqua Marcia.
IV. ” Tepula.
V. ” Julia.
VI. Aqua Virgo.
VII. ” Alsietina (which is also called Augusta[6]).
VIII. ” Claudia.
IX. Anio Novus.
Frontinus describes the above nine aqueducts in order, giving details as
to the source of the water in each, the quantity, and the distribution.
Such extracts as are calculated to throw light upon the existing remains,
are given in the course of the following remarks. Seven other Aqueducts
were added after the time of Frontinus at different periods, of which an
account will also be found in the second part of this Chapter.
I. THE AQUA APPIA (A.U.C. 441, B.C. 312).
“The _Aqua Appia_ was brought into Rome by the censor Appius Claudius
Crassus, afterwards called _Cæcus_ (the blind), who also caused the Via
Appia to be constructed from the Porta Capena to the city of Capua[7].”
“The Appian stream rises in the Lucullan fields on the Via Prænestina,
between the seventh and eighth milestone, and about 780 paces (or about
¾ of a mile) off on the left-hand side. The channel from its source
to the ‘_Salinæ_,’ which is a spot near the Porta Trigemina, measures
11 miles, 190 paces (about 300 yards) in length. For 11 miles, 130
paces, (about 200 yards,) the channel runs underground, and for 60
paces (about 100 yards) it is carried above ground on a substructure
and arcade (in the part) nearest to the Porta Capena[8]. At the ‘_Spes
(Specus) Vetus_,’ (the old _specus_ or conduit,) on the confines of the
Torquatian and Pallantian gardens, a branch called the _Augustan_ was
added to it by Augustus as supplementary, whence it received the name of
‘Gemelli[9]’....”
“The distribution of the Appian water begins at the bottom of the _Clivus
Publicii_ at the Porta Trigemina[10]; the stream having passed beneath
the Cœlian and Aventine Hills.”
“... The measure at the head of this could not be obtained because it
consists of two channels. At the Gemelli, however, which is under[11]
the _Spem (Specum) Veterem_, (the old conduit,) where it joined with the
Augustan branch, I found the height or depth of the water to be 5 ft.,
the width 1 ft. 9 in., which makes the area 8 ft. 9 in.: ... it should be
noticed that the water in many parts of the City was observed to be lost,
that is, by trickling away. Moreover we found some of it intercepted by
illegal pipes within the City; without the City, owing to the pressure,
that which was underground (at the head 50 ft.), received no injury[12].”
The Lucullan fields, in which are the sources of the Aqua Appia, are
nearly due east from Rome, on the bank of the river Anio, at about six
miles from the present gates of Rome, and three quarters of a mile off
the Via Collatina, now a cart-road. This is the old Via Prænestina, which
went through Collatia, now called Lunghezza, about two miles higher up
the river Anio, at the point where the smaller river Osa falls into it.
In this part the old paved road remains for some distance in use, both
before and after the entrance to Collatia, and was the more direct road;
the present carriage-road, now called Prænestina, was the Via Gabina, and
went through or near to Gabii, but was not so direct a line to Præneste
or Palestrina as the one through Collatia. The old road passes close in
front of the ancient stone quarries, on the bank of the Anio, in which
one of the springs or reservoirs of the Aqua Appia is situated; the
pavement of it remains, and is now used as a foot-path only.
There are several springs or sources for this aqueduct, and also several
ponds to collect the rain-water, made in the clay, the water from all
of which was collected into a central reservoir cut in the rock, with
a large well over it. There are also seventeen wells visible in two
lines, eight in one and nine in the other, converging and meeting in the
central reservoir. The soil is clay upon stone. The _specus_ is here a
large tunnel cut in the rock, and the wells descend into it. They may be
distinguished from above by the bramble-bushes which grow over and cover
each of the openings, and do not grow on the other part of the field;
each well is also protected by a wooden rail, to hinder cattle from
falling into it. The water still runs through in some parts. Near to this
reservoir is a tomb of very early character, similar to what are usually
called Etruscan[13] tombs, cut out of the rock.
As the length of its course was rather more than eleven miles, while the
distance by the Via Prænestina direct was only between seven and eight,
it is clear that it did not follow that road. It was carried to the south
towards the Via Labicana by a winding course, according to the levels of
the ground. The Aqua Virgo, whose source is in the same Lucullan fields
as the Appia, is carried to the north by another winding course of a
greater length, to supply the northern parts of the city.
The course of _the old Via Prænestina_[14] has undergone but little
change, and the 7th milestone is soon measured. A little beyond it, and
780 paces off on the left of the road (i.e. on the northern side), we are
brought to a point[15] where the sources of the Aqua Appia are still to
be seen in caves formed by ancient stone quarries, near a tenement called
_La Rustica_. One cave is of a triple form, with three springs, and the
soil above the stone is much mixed with clay. These three springs meet
at the mouth of the cave in one stream, which runs in the old _specus_
cut in the rock, but open at the top, and having the appearance of a mere
country ditch, half hid by the grass and weeds in the winter, and in
the summer months entirely concealed by them. This _specus_ runs across
a low meadow for about a quarter of a mile. It crosses the line of the
Aqua Virgo, the respirators of which cross this meadow in an opposite
direction; the sources of the Virgo are about a mile further from Rome,
on the same road. It then enters the rock again in a tunnel, and at
this point is the first _castellum_ or reservoir, with a large circular
well cut out of the rock, which forms the vault over it. There are the
grooves for sluices at each end of the reservoir, and an opening has been
made into the tunnel a little beyond this reservoir. The course of the
aqueduct is then in a tunnel entirely underground, in the direction of a
series of ancient caves, through which, or by which, it must pass, but
being underground it cannot be seen. These caves are evidently an ancient
stone quarry, but of later character than the one first mentioned. In the
earliest one, at the source, the stone has been split off the rock, not
cut; in the other caves, the stone has been well cut, and of these many
are to be seen, the openings being large square apertures like doorways,
but side by side in the face of the scarped cliff, not following each
other: a practice common in quarrying, where the circumstances require
it, down to the present day. Between the chambers are massive square
or oblong piers, left to support the vault and the earth above. At the
bottom of one of these chambers is water running from another spring,
and the shepherds state that there is an opening from it to the _specus_
of the aqueduct; but as the bottom is filled up to the depth of several
feet with broken stone, it cannot be seen. Some of the chambers of this
ancient quarry have been used as a burying-place, probably for the
neighbouring town of Collatia. The graves are cut out in the side of the
walls, like the _loculi_, and there are also chambers like the _cubicula_
of a catacomb. The tombs of this necropolis of Collatia are very ancient,
perhaps anterior to the Kings of Rome, and certainly not posterior to the
Republic. This stone has been cut out in large square or oblong blocks,
such as are usual in work of the time of the Kings; it is probable that
Appius Claudius made use of a quarry which he found, and that the ground
was not excavated for the purpose of the aqueduct only.
From this point the course was entirely underground, therefore no
traces are visible without some difficulty. Incidentally, as we have
seen, Frontinus notes, that at the head the water ran as much as fifty
feet below the surface, and was thus protected from being fraudulently
diverted. It could not have taken a very direct line, as the levels of
the crossing valleys must have necessitated here and there a circuitous
course; and moreover this is clearly implied by Frontinus, who says that
the total length from the source to the “Salinæ” was more than eleven
miles, while the distance in a direct line is less than nine miles. As it
had no _piscina_[16], it flowed on in an uninterrupted course to the spot
where it was distributed for the public service.
One branch seems to have entered Rome under the line of the Claudian
arcade, near the Porta Maggiore[17], and its course within the city is
not difficult to follow, since for certain purposes access has been made
in more than one place into the old _specus_, part of which is used to
carry the lead pipes of the Aqua Felice to the Hospital of the Lateran
and other places. From the surface where one of the shafts is situated
to the bottom of the channel, is a depth of twenty-five feet. No water
runs along it at present, except in the metal pipes from the Aqua Felice,
belonging to the modern system.
The direction of this channel, after it enters Rome, happens to be easily
seen above, as it is marked throughout its course, from the eastern
end of the Cœlian to the Arch of Dolabella, by the fine arches of the
Neronian branch from the Claudian Aqueduct erected almost over it. It is
very probable that one of the laws (referred to by Frontinus as having
been in existence long before his time) respecting aqueducts was in force
from the commencement, namely, that there should be no buildings of any
kind within ten feet on either side of the aqueducts; thus an open space
was probably existing at the time when Nero wished to carry water to his
magnificent reservoir at the north-western end of the Cœlian, and of this
he availed himself in rearing the splendid arcade which is called by his
name. It will be remarked, however, that the brick buttresses actually
came down to the flat roof of the original _specus_ of the Appian. The
top of that _specus_ was raised to a greater height by the engineers
of Sixtus V., and in this enlargement the underground supports of the
Neronian arches are cut through to give headway to the _aquarii_ passing
along the channel. They have however to stoop their heads as they pass
under each buttress.
The old tunnel _specus_ was discovered in the time of Sixtus V., (Felice
Peretti), filled up by clay deposit to the depth of three feet, or half
the height of the _specus_, as in other places, and the builders found it
easier to raise it, for the _aquarii_ to go along it, than to clear it
out. They therefore knocked away the flat tile-covering of the time of
Nero, and raised a vault of rubble-stone three feet higher.
From the great subterranean reservoir, still in use for the water of a
spring, near the Arch of Dolabella, to the edge of the western cliff of
the Cœlian is but a short distance, and here the _specus_ seems to run in
a bank dividing the vineyard or garden of the Villa Mattei from that of
the monks of S. Gregory, on which a wall has been built. At this point
subsequent alterations, and especially those under the Emperors Nerva and
Trajan, have buried to a great depth the actual remains of the original
aqueduct; but this later work occupies the same line, and must be
described. We first come to a large _piscina_ or filtering-place on the
cliff of the Cœlian, immediately above the Porta Capena. This _piscina_
is divided into two parts, one above the other; but both are below the
top of the cliff, and are faced with brick and reticulated work of the
time of Trajan. There are remains of two _specus_ running along against
the face of the cliff; of the upper one the lower part, or pavement, of
_Opus Signinum_, only remains, and this runs down in a sloping direction
from the upper reservoir to a lower one, a little to the south of it,
which is very extensive. This lower reservoir consists of several
parallel chambers, through which, or rather in front of which, another
_specus_ runs at a lower level; this appears to be horizontal. This
_specus_ goes on in the direction of the ruins of a building of various
periods, possibly the remains of the Ædes Camenarum, and passes then to
the south in the direction of the Thermæ of Severus and Commodus.
Another branch was evidently afterwards made from the upper reservoir
going towards the north for a very short distance, merely for one of
the usual angles; then, turning again to the west, in the valley below,
there is another large _castellum aquæ_, or reservoir of five chambers,
all as usual oblong and side by side. This is on lower ground, and is
built upon the wall of Servius Tullius, where it crosses the valley;
the upper part of this reservoir has been made into a house for the
gardener. The underground part of the chamber nearest to the Cœlian
is built of the large square blocks of tufa usual in the time of the
Kings, and belongs to the fortifications of the Porta Capena, over the
Via Appia, which here passed close under the Cœlian; the other chambers
appear, from the bricks, to be of the time of Trajan. From this point
to the Piscina Publica, the line of tall brick piers of Trajan can be
distinctly traced by the existing remains, passing across to the other
side of the road and of the stream here close to it[18]. The ruins of the
Piscina Publica, as rebuilt by Trajan, remain visible under the corner of
the Pseudo-Aventine, near S. Balbina, and from this the water was again
distributed in different branches. At this point, let it be observed,
and only at this point, is the valley which divides the Cœlian from the
Aventine sufficiently narrow to admit of agreement with the direct and
clear assertion of Frontinus, that here alone, throughout the whole
course, was it carried on a substructure and on arches for a distance of
one hundred yards.
Although there are no remains of the _specus_ now visible at this spot,
because the gate has been destroyed, there can be little doubt that the
channel for the water was carried _over_ the southern gate of _the city_
according to its extent at that time. This gate was called the Porta
Capena; and as the Appian aqueduct was allowed to fall into decay, it
gave rise to the descriptions both of Martial and Juvenal, who describe
it as wet or moist[19].
The excavations made in 1868 and 1869 under the direction of Mr. Parker,
with the help of the British Archæological Society of Rome and the Roman
Exploration Fund, have clearly shewn the _specus_ of the Aqua Appia and
those of two other aqueducts carried upon the _agger_ of Servius Tullius
across the valley from the Cœlian to the Aventine, with branches to the
left running into the subterranean chambers of the Piscina Publica. These
underground chambers are of the time of the Republic, the walls are built
of rubble stone as usual at that period, and there are small openings
through these walls for the circulation of the water, although the upper
part has been rebuilt in the time of Trajan, as the remains of the wall
are faced with the brickwork usual in his time. The lowest _specus_ is
cut out of tufa rock _under_ the wall of Servius Tullius, which is built
of the usual large blocks of tufa.
The principal branch went underground to the cave reservoir at its mouth,
on the level of the quay of the Marmorata between that and the Salaria,
just outside of the old Porta Trigemina; the old _agger_ in which that
gate was situated still forms the southern or lower boundary of the wharf
of the Salaria. Part of the course of this earliest _specus_, that of
the Appia, can be traced and seen in a subterranean stone quarry nearly
under S. Sabba. The _specus_ is six feet high and two feet wide, and
it is filled up to nearly half its height by solid clay, evidently the
deposit left by the water. The old _specus_, long after it had been
out of use, seems to have been employed by the quarrymen: as it was a
tunnel in the tufa rock just high and wide enough for a man to walk in,
by cutting away one side they made it wide enough for a horse and cart
to carry the stone, and they raised the vault as high as was convenient
for the purpose of making an entrance into the quarry. The series of
wells descending into the old _specus_ from the gardens above remain at
intervals, with notches for steps cut in the rock to enable a man to
go up and down when required. The course of the _specus_ is cut off by
the road to the Porta Ostiensis, but probably that road was originally
carried over it[20] at the crossing; it then passed through another
large subterranean quarry nearly under S. Prisca, to the cave reservoir
at its mouth[21].
Before arriving at the two large reservoirs just outside of the garden
of the Sessorium, now Sante Croce, the _specus_ of the Appia must have
passed by another smaller reservoir at the same low level, near the ruins
of the apse of a hall, miscalled the temple of Venus and Cupid. This
seems likely to have been the point at which the branch _specus_, coming
from the north, entered Rome, and it was then carried on to the two large
reservoirs outside this garden, supposed to have been the _Gemelli_[22].
Below the “Salinæ” or salt warehouses on the bank of the Tiber, and near
the “Porta Trigemina,” the water was “distributed.” This was also close
under the Clivus Publicii, or the slanting zig-zag road leading up from
the wharf to the top of the hill.
So far the general course can be traced; but the exact point of entrance
into Rome could not be fixed without excavations, which have not as yet
been made. There are, however, some _data_ given by Frontinus which
should not be overlooked, as they bear incidentally upon the course of
some other of the aqueducts.