cities above named.

In 1882, I was employed by the Postal Telegraph Company to put the Leggo
automatic system into practical shape, and, if possible, transmit 800
words per minute between New York and Chicago.

It was proposed to string a steel-copper wire, the copper on which was
to weigh 500 lb. to the mile.

When complete, the wire was rather larger than No. 3, English gauge, but
varied in diameter, some being as large as No. 1, and it averaged 525
lb. of copper per mile and = 1.5 ohms. The surface of this wire was,
however, large.

Dr. Muirhead estimated its static capacity at about 10 M.F., which
subsequent tests proved to be nearly correct.

It will be understood that this static capacity stood in the way of fast
transmission.

Resistance and static capacity are the two factors that determine speed
of signaling.

The duration of the variable state is in proportion to the square of the
length of the conductor, so that the difficulties increase very greatly
as the wire is extended beyond ordinary limits. According to Prescott,
"The duration of the variable condition in a wire of 500 miles is
250,000 times as long as in a wire of 1 mile."

In other words, a long line _retains a charge_, and time must be allowed