at the
public expense, under the supervision of professional engineers and
surveyors, and kept in repair by the districts and provinces through
which they passed.

But during the dark ages, when arts were lost, when popular learning
disappeared or found shelter only in cloisters and convents, when
commercial intercourse between nations vanished, and when civilization
itself lay fallen and inert, these magnificent Roman roads were unused
and left to the destructive agencies of time and the elements of
Nature. Rains and floods washed away and inundated their embankments;
forests and rank vegetation overgrew and concealed them; winds covered
them with dust and heaps of sand; and little by little in the process
of ages their hard surfaces and massive foundations were somewhat
broken and caused to partially decay. That their remains still exist in
every part of the world which ever bore up the Roman legions is
conclusive evidence that they were built by master workmen who realized
that they were responsible to posterity and to the eternal powers.

"In the elder days of Art
Builders wrought with greatest care
Each minute and unseen part;
For the gods see everywhere."

In China, at one time, labor was so abundant that it was kept employed
in constructing great walls and ponderous roads. The road-bed was
raised several feet above the level of the ground by an accumulation of
great stones, and then covered with huge granite blocks. It was found
that in time the wheels of vehicles wore deep ruts in the stones, while
the travelled part of the road became so smooth that it was almost
impossible for animals to stand thereon.

In the ancient empires of Mexico and Peru, where there were no beasts
fit for draught or for riding, magnificent roads were constructed for
the treble purpose of facilitating the march of armies, accommodating
the public traffic, and ministering to the convenience and luxury of
the lordly rulers. In Peru two of these roads were from fifteen hundred
to two thousand miles long, extending from Quito to Chili,--one by the
borders of the ocean, and the other over the grand plateau by the
mountains. Prescott says: "The road over the plateau was conducted over
pathless sierras buried in snow; galleries were cut for leagues through
the living rock; rivers were crossed by means of bridges that swung
suspended in the air; precipices were scaled by stairways hewn out of
the native bed; ravines o