ngauger Wrote:I Didn't know about the swing bridge on the High Line... Why was it there???? I always wondered what the "structures" were there for... Cool!!!!!
Yup, the catenary would be lifted and pulled to the side (and probably sag on the bridge a little), allowing the span to swing. You can see a ladder at the middle of the span down the side to where the swing mechanism must have been.
Your question seemed like a simple question, but you have thrown me down quite a path of research!
First a correction, Technically this bridge is on the Delaware Extension, travelling over the Schuylkill River. This might explain why you didn't know about it, my mistake!
. I probably could be forgiven for mistaking it, however, since I saw the rear of this train on the High line shortly before I too this photo, and due to the separation of passenger and freight lines, it looked to me like a continuation of the High Line to me.
At first I figured there must have been an Arsenal near Arsenal interlocking, but it turns out there was no such arsenal at the time the line was built. Apparently (though I might read about this further), much earlier in the 1800s, there WAS an arsenal on the east side of the bridge across the river from Arsenal Interlocking, from which Lewis and Clark took on supplies for their journey west. The PRR felt that was an appropriate name.
It seems that the answer is a lot less exciting, since 1950 aerial views show lots of barges tied up just north of the Delaware Extension. My guess is that there was some small marine traffic. Considering that there was a Reading line going up the east side of the Schuylkill river, and the Northeast corridor moving up the west side soon after Arsenal, My guess was that marine traffic was drying up, I'm not sure where else a commercial boat could go.
For those unfamiliar with this part of Philadelphia, Arsenal was once the place where freight trains would diverge of the Northeast Corridor onto the "High Line Branch", which allowed trains travelling between Baltimore and points North to literally pass over 30th Street station. The High Line would rejoin the Northeast Corridor at Zoo interlocking. The Delaware Extension also connected with the High Line at Arsenal, and this line went for 3.9 Miles to Greenwich yard, (which is very visible from 95 south of the Walt Whitman Bridge and the Philadelphia Stadiums). At one time, massive ore and mineral trains were handled here, as well as food and produce and freight bound for the ports on the Delaware River. Interestingly, this is also the freight yard that became a passenger terminal for the Army Navy Games. Since only part of the yard was under wire, GG1s would coast into the yard, and switchers would pull the motors back to the wire and set them off again. As many as 38 passenger trains were handled with high efficiency on this small branch, and the operation was a point of pride on the PRR.
Today, Arsenal tower controls SEPTA's R3 line. The High Line no longer connects to the Northeast corridor, and instead links with the former Reading near Zoo, and goes directly onto the Delaware Extension.