atters, and one upon which the
health of the populations to a very large extent depends, I propose to
give a short account of some of the more important works carried out for
this purpose by the ancient Romans--the great sanitary engineers of
antiquity--more especially as I have had exceptional opportunities of
examining many of those great works in Italy, in France, and along the
north coast of Africa. Of the aqueducts constructed for the supply of
Rome itself we have an excellent detailed account in the work of
Frontinus, who was the controller of the aqueducts under the emperor
Nerva, and who wrote his admirable work on them about A.D. 97.

It may be interesting in passing to mention that Frontinus was a
patrician, who had commanded with distinction in Britain under the
emperor Vespasian, before he was appointed by the emperor Nerva as
controller (or, we should say, surveyor) of the aqueducts. He was also an
antiquarian, and in his work he not only describes the aqueducts as they
were in this time, but also gives a very interesting history of them. He
begins by telling us that for 441 years after the building of the
city--that is to say, B.C. 312--there was no systematic supply of water
to the city; that the water was got direct from the Tiber, from shallow
wells, and from natural springs; but that these sources were found no
longer to be sufficient, and the construction of the first aqueduct was
undertaken during the consulship of Appius Claudius Crassus, from whom it
took the name of the Appian aqueduct. This was, as may be expected from
its being the first aqueduct, not a very long one; the source was about
eight miles to the east of Rome, and the length of the aqueduct itself
rather more than eleven miles, according to Mr. James Parker, to whose
paper on the "Water Supply of Ancient Rome" I am indebted for many of the
facts concerning the aqueducts of Rome itself. This aqueduct was carried
underground throughout its whole length, winding round the heads of the
valleys in its course, and not crossing them, supported on arches, after
the manner of more recent constructions; it was thus invisible until it
got inside the city itself, a very important matter when we consider how
liable Rome was, in these early times, to hostile attacks.

It was soon found that more water was required than was brought by this
aqueduct, and it was no doubt considered desirable to have tanks at a
higher level in the city than those suppl