lel to this ridge at
distances of ten to fifteen feet, dividing each half of the avenue into
four or five sections, their width increasing as they approach the
middle. All trucks or drays moving at less than seven miles an hour
are obliged to keep in the section nearest the building line, those
running between seven and fifteen in the next, fifteen to twenty-five
in the third, twenty-five to thirty-five in the fourth, and everything
faster than that in the section next the ridge, unless the avenue or
street is wide enough for further subdivisions. If it is wide enough
for only four or less, the fastest vehicles must keep next the middle,
and limit their speed to the rate allowed in that section, which is
marked at every crossing in white letters sufficiently large for him
that runs to read. It is therefore only in the wide thoroughfares that
very high speed can be attained. In addition to the crank that
corresponds to a throttle, there is a gauge on every vehicle, which
shows its exact speed in miles per hour, by gearing operated by the
revolutions of the wheels.

"The policemen on duty also have instantaneous kodaks mounted on
tripods, which show the position of any carriage at half- and
quarter-second intervals, by which it is easy to ascertain the exact
speed, should the officers be unable to judge it by the eye; so there
is no danger of a vehicle's speed exceeding that allowed in the section
in which it happens to be; neither can a slow one remain on the fast
lines.

"Of course, to make such high speed for ordinary carriages possible, a
perfect pavement became a sine qua non. We have secured this by the
half-inch sheet of steel spread over a carefully laid surface of
asphalt, with but little bevel; and though this might be slippery for
horses' feet, it never seriously affects our wheels. There being
nothing harder than the rubber ties of comparatively light drays upon
it--for the heavy traffic is carried by electric railways under
ground--it will practically never wear out.

"With the application of steel to the entire surface, car-tracks became
unnecessary, ordinary wheels answering as well as those with flanges,
so that no new tracks were laid, and finally the car companies tore up
the existing ones, selling them in many instances to the municipalities
as old iron. Our streets also need but little cleaning; neither is the
surface continually indented, as the old cobble-stones and Belgian
blocks were, by