hard to find weathered and worn single-sided die cut steel porcelain enameled "live wire" cautionary or danger sign possibly fabricated by the safety first supply co., pittsburgh, pa. the antique industrial sign was likely posted near a power supply structure for an electrified third rail. the bold black lettering remains largely intact. significant wear found along the edges. early in the 20th century the pennsylvania railroad tried electric power for their trains. first was the new york terminal area, where tunnels precluded steam locomotives; a direct current (dc) 650-volt third rail powered pennsylvania railroad locomotives. the system was put into service in 1910. the next area to be electrified was the philadelphia terminal area, where pennsylvania railroad officials decided to use overhead lines to supply power to the suburban trains running out of broad street station. unlike the new york terminal system, overhead wires would carry 11000-volt 25-hertz alternating current (ac) power, the system used for all future installations. pennsylvania railroad's president william atterbury announced in 1928 plans to electrify the lines between new york, philadelphia, washington and harrisburg. in january 1933, through main-line service between new york and philadelphia/wilmington/paoli was placed in operation. the first test run of an electric train between philadelphia and washington occurred on january 28, 1935. to complete the electrification project initiated in 1928, work was started january 27, 1937, on the main line from paoli to harrisburg; the low-grade freight line from morrisville through columbia to enola yard in pennsylvania; the freight line from perryville to columbia; the freight line from monmouth junction to south amboy; and the freight line from landover, maryland through washington, dc to potomac yard in alexandria, va (now called the landover subdivision and rf&p subdivision of csx). in less than a yearon the following january 15the first passenger trainthe metropolitanwent into operation over the newly electrified line from philadelphia to harrisburg. on april 15 the electrified freight service from harrisburg and enola yard east was inaugurated, thus completing the pennsy's eastern seaboard electrification program with a total of 2,677 miles of track electrified41 percent of the total electrically operated standard railroad trackage of the united states. portions of the electrified trackage are still in use, owned and operated by amtrak as the northeast corridor and keystone corridor high-speed rail routes. measures 18 x 12 inches.