carpenter smiled faintly.

"He was looking for the 'lost water,'" he said, in a tone of contempt.

The faint smile slowly reflected itself in the mason's face. The two
finished their wine, lit their pipes again, left the price of their
drink on the table without disturbing the host and went away.

So far as any outsider could have judged, the expert's curiosity and
the few words exchanged by the workmen referred to the so-called "lost
water," which might be somewhere under the north-west corner of the
Palazzo Conti, and no one unacquainted with subterranean Rome could
possibly have understood what any of the three meant.

The "lost waters" of Rome are very mysterious. Here and there, under
old streets and far down amongst the foundations of ancient palaces,
there are channels of running water which have no apparent connection
with any of the aqueducts now restored and in use. It is a water that
comes no one knows whence and finds its way to the Tiber, no one knows
how. It is generally clear and very cold, and in the days when the
aqueducts were all broken and most people drank of the river, the
"lost water" was highly prized. It appears in the most unexpected
places, sometimes in great quantities and seriously interfering with
any attempt to lay the foundations of a new building, sometimes black
and silent, under a huge flagstone in an old courtyard, sometimes
running with an audible rush through hidden passages deeper than the
deepest cellars. It has puzzled archaeologists, hydraulic engineers
and architects for generations, its presence has never been
satisfactorily explained, there seems not to be any plan of the city
which shows its whereabouts, and the modern improvements of the