TIBERIS
the most important river of Central Italy. The importance of
the site of the Palatine and of Rome is mainly due to its command of the
crossing of the Tiber just below the island (see
PONS SUBLICIUS), which
must be of great antiquity, and was probably the only one in the whole
lower course of the river.
The derivation of the name is uncertain (Varro,
RR iii. 16;
LL v. 30;
Serv. ad
Aen. viii. 332), but its antiquity is vouched for by its appearance
in the augural books (Cic. de nat. deor. iii. 20). It was also known as
Albula, though it is incorrect to connect the name with albus (as Servius
ad Aen. cit. and Festus 4 do). Hiilsen connects it with the Ligurian
root ALB- or ALP-, meaning 'mountain,' so that Albula would mean
the mountain stream (for a small stream of the same name in Picenum,
see
RE ii. 1331). Vergil (ib. viii. 64) calls it caeruleus, a colour which
it not infrequently acquires when the blue sky is reflected in it; but its
general and more approproate epithet is flavus (ib. vii. 31; Hor.
Carm.
i. 2. 13;
ii. 3. 18).
It is a turbulent river and much subject to floods, which have always
been a source of great danger to the city. No less than 132 inundations
have been recorded (
BC 1895, 283-300, for the mediaeval and Renaissance
periods). Julius Caesar had a scheme for cutting a new channel a Ponte
Mulvio secundum montes Vaticanos; see
CAMPUS VATICANUS (Cic.
ad
Att. xiii. 33. 4; HJ 493-494).
The cura Tiberis under the republic was in the hands of the censors.
Protecting walls were built at least as early as the second century B.C.
(see
CLOACA MAXIMA, and cf.
BC 1889, 165-172;
Mitt. 1889, 285), and
we have nineteen of the terminal stones erected by P. Servilius Isauricus
and M. Valerius Messalla in 54 B.C. (
CIL vi. 31540 a.p, gives fifteen;
and four more have since come to light (
BC 1897, 62, 275;
1906, 117;
NS 1896, 524;
1897, 10, 252;
1906, 207). All of them are given in
CIL i². 766, a-t). They extend from the Pons Mulvius, at the second
mile of the via Flaminia, downstream as far as the Almo on the left
bank, while one was seen in the seventeenth century near S. Passera
(opposite S. Paolo) on the right bank. On the other hand, it was the
praetor urbanus who, a little earlier (the inscriptions are attributed to
the time of Sulla), traced the boundary line between public and private
property at Ostia (
NS 1910, 554;
YW 1911, 12;
1920, 89; Calza
Ostia, 85).
The next termination was carried out by the consuls of 8 B.C.,
C. Asinius Gallus and C. Marcius Censorinus, and twenty of these cippi
remain (
CIL vi. 31541, a-u), and a third by Augustus himself in the
following year, twenty-two cippi remaining (ib. 31542, a-w). In this
termination the distance in a straight line r(ecta) r(egione) to the next
cippus is given in feet, on the front, back or side (cf. CIL cit. p. 3110;
see
RIPA VEIENTANA).
In 15 A.D. a great inundation occurred, and the cura riparum was
instituted by Tiberius (Tac.
Ann. i. 76; Cass.
Dio lvii. 4 ; Suet. Aug. 37
is mistaken; cf. Mommsen, RGDA2 29;
BC 1894, 254-6; CIL p. 3109).
The curatores, who were five in number, replaced several of the
earlier cippi by new ones, adding to the original inscription the words
curatores riparum qui primi fuerunt ex senatus consulto restituerunt.
Their authority extended as far as Ostia, where one of their cippi and
one of 24-37 A.D. have been found (
NS 1921, 258-262; cf. CIL xiv.
192; YW 1922-3, 106). A little later on other curatores restored a part
of the bank near the pons Cestius (
CIL vi. 31543), and set up other cippi,
three of which remain (31544 a-c -- before 24 A.D.). From the reign
of Claudius we have a cippus of the curatores who '
ripam cippis positis
terminaverunt a Trigario ad pontem Agrippae' (31545), while under
Vespasian and afterwards only a single curator is named, it being doubtful
whether one functioned for the whole collegium, or whether henceforth
there was only a single curator (31546-8 -- 73-74 A.D.). We have other
cippi under Trajan (31549-51 -- 101 and 104 A.D. -- seventeen set up by
Ti. Julius Ferox curator alvei Tiberis ... ct cloacarum urbis), Hadrian
(31552 -- 121 A.D.), Antoninus Pius (31553-4 -- 161 A.D.), Septimius
Severus (31555-197 -- 198). None of these later groups is very large;
and then there is a gap till Diocletian (31556 -- 286-305 A.D.).
See
PONS AELIUS for the regulation of the channel there; and for
the bridges, see PONS. For the termination and embankments in general,
BC 1889, 165-172;
1893, 14-26; LR 9-13; Pl. 14-17, 75-77; PT 180.
For the Tiber as a whole, see Nissen, Italische Landeskunde, i. 308-324;
for floods in antiquity, Jord. i. I. 128, and in the Middle Ages, Gregorovius
in Buonarroti, 1876, 313-321; 345-355.