is in general a person who examines things
by a libra;
but the name was, in particular,
applied to two kinds of persons.
1. Librator aquae,
a person whose knowledge was
indispensable in the construction of aqueducts, sewers, and other structures
for the purpose of conveying a fluid from one place to another. He examined
by a hydrostatic balance (libra aquaria
relative heights of the places from and to which the water was to be
conducted. Some persons at Rome made this occupation their business, and
were engaged under the curatores aquarum,
though architects were also expected to be able to act as libratores.
(Plin. Ep. 10.50
Frontin. de Aquaed.
105; compare Vitr.
; Cod. 10, 66, 1.) [L.S
2. Libratores (or libritores,
according to some MSS.)
were soldiers who are coupled with slingers (funditores
) in Tacitus, Tac. Ann.
. There is much
difference of opinion about them. Some recent writers take them to be
engineers of some description engaged in the management of tormenta,
and the derivation librare,
“to level,” is suggested as though they levelled and directed
them. It can be inferred from Marquardt's note
2.526) that he also classes them with the
managers of tormenta,
but he gives no definite
statement of his opinion. In Tac. Ann.
, in a fresh sentence after the words “multos tormentis
faces et hastas incutere jubet,” we find “libratoribus et
funditoribus attributus locus unde eminus glandes torquerent,”
from which the inference surely would be that they have nothing to do with
and are an arm of the service
more like the slingers: and the other passage of Tacitus tells the same way,
“funditores libratoresque excutere tela et proturbare hostes
jubet: missae et tormentis hastae.” Forcellini conceives slings
which discharged stones of a pound weight to explain the libralia
or librilia saxa
(cp. Caes. Gal. 7.81
). If this were a correct
view, the key to the precise explanation might be found in Liv. 38.29
, where, at the siege of Same in B.C.
189, slingers are described as brought from Achaia, who “a
pueris” practised slinging saxa globosa:
the force is greater than that of the Balearic slinger, and the sling is not
a single thong but a triple “scutale” made stiffly, so that the
missile “librata quum sederit velut nervo missa excutiatur:”
apparently they could fire more nearly point-blank and with heavier charge.
But against this we have first the fact that the libratores
were to be distinguished from slingers generally, and
not merely from Balearic slingers; and, secondly, the passage of Vegetius,
2.23, which tells us that libralia saxa
thrown by the hand
and with less preparation as requiring no sling:
and Festus explains librilia
as “saxa ad brachii crassitudinem
loris revincta.” This suggests the conclusion that the stones
were swung by the thong, to which they were fastened, and discharged thong
and all. And it is perhaps best to regard the libratores
as stone-throwers employed, not with the tormenta,
but along with the funditores
(cp. the λιθοβόλοι
coupled with σθενδονῆται,
), throwing with the hand by the thong
attached missiles heavier than the glans
slinger: and the word should probably be connected with the sense of swinging
in Livy, l.c.
), rather than with libra,