ere was the signal
corps, the "eyes" of the army, made up mostly of young lieutenants and
non-commissioned officers detailed from the several regiments. There
were two such officers from Scranton, namely, Lieutenant Fred. J.
Amsden, One Hundred and Thirty-sixth Pennsylvania Volunteers, and
Lieutenant Frederick Fuller, Fifty-second Pennsylvania Volunteers,
besides a number of enlisted men.

Another important branch of the service was the telegraph corps. It was
remarkable the celerity with which wires would be run along the ground
and on brush, day by day, keeping the several corps constantly in touch
with the commanding general. There were comparatively few telegraph
operators that could be detailed, and many had to be hired,--some boys
who were too young to enlist. Dr. J. Emmet O'Brien, of this city, was
one of the most efficient of the latter class.

It was Dr. O'Brien, then operating below Petersburg, who caught the
telegraphic cipher of the rebels and by tapping their wires caught many
messages which were of material assistance to General Grant in the
closing movements of the war. It was he also who in like manner caught
the movements of Jeff Davis and his cabinet in their efforts to escape,
and put General Wilson on his track, resulting in his final capture. Mr.
Richard O'Brien, the doctor's older brother, for many years
superintendent of the Western Union Telegraph lines in this end of the
State, was at that time Government Superintendent of Telegraphs, in
charge of all its telegraphic operations in Virginia and North Carolina.
He could tell many a hair-raising experience. He related to me the
following incident, which occurred during Grant's operations around
Petersburg, to illustrate the enterprise of the enemy in trying to get
our telegrams, and the necessity of sending all messages in cipher. They
never succeeded in translating the Union cipher. But one day an operator
at Washington, either too lazy or too careless to put his message in
cipher, telegraphed to the chief commissary at a place below City Point
that fifteen hundred head of beef cattle would be landed at that point
on a certain day. The message was caught by the rebels. The beef cattle
were landed on time, but in the meantime Wade Hampton had swept in with
a division of rebel cavalry and was waiting to receive the cattle. With
them were captured a handsome lot of rations and a number of prisoners,
including all of Mr. O'Brien's telegraph operators