must be somewhat elaborate. And so it is. Indeed, so complete is the
organization and management of _employées_ upon the New York and
Erie Railroad, that the General Superintendent at his office can at
any moment tell within a mile where each car or engine is, what it
is doing, the contents of the car, the consignor and consignee, the
time at which it arrives and leaves each station, (the _actual_ time,
not the time when it _should_ arrive,) and is thus able to correct
all errors almost at the moment of commission, and in reality to
completely control the road.

The great regulator upon long lines of railroad is the electric
telegraph, which connects all parts of the road, and enables one
person to keep, as it were, his eye on the whole road at once.

A single-track railroad, says Mr. McCallum, may be rendered more
safe and efficient by a proper use of the telegraph than a
double-track railroad without,--as the double-tracks commonly
obviate collisions which occur between trains moving in _opposite_
directions, whilst the telegraph may be used effectually in
preventing them between trains moving either in _opposite_
directions or in the _same_ direction; and it is a well-established
fact, deduced from the history of railroads both in Europe and in
this country, that collisions from trains moving in the _same_
direction have proved by far the most fatal and disastrous, and
should be the most carefully guarded against.

From the admirable report of Mr. McCallum, above referred to, we take
the following:--Collisions between fast and slow trains moving in
the same direction are prevented by the following rule: 'The
conductor of a slow train will report himself to the Superintendent