I wonder if the lower signal ever changes from red? The next siding is Coleman, 5-1/2 Miles ahead. The lower red signal as seen in my second photo taken at Blythewood, SC never changes aspects -- it's always red and there's no siding ahead, except for the yard in Columbia and it's many miles distant. I almost wonder if the lower red signals at both locations are there to amplify the importance of the absolute signal? Yep, further explanation is needed!
My interest in signals and interlockings was influenced by two guys I used to hang out with long ago. Both were older and well schooled, and one had his career in railway signaling. The other guy had working signals in his yard. The business of keeping trains apart is far more complex than I ever imagined.
Here's an interesting thread that discusses the Southern's lower red only aspect. I didn't follow all the details in the explanation but it is part of a "positive signal" that is intended to be always lit. http://cs.trains.com/trn/f/111/t/165702.aspx?page=1
Thanks hoyden -- it seems that our assumption is correct that it's an Absolute signal and that the lower red signal is constantly lit. Thanks for posting the link!
Heehee -- I like the St. Paddy's Day green theme. Here's ex-E-L SW-9 No. 438 on the Black River & Western at Ringoes, NJ, taken 04/01/2017.
Ha, Canadians bragging that they can handle tonnage while our Class-1s need two or three at the head end. LOL Thanks for the photo, Buddy.
Nothing green around here today, so to the way back machine we go! All the way to 22 Dec 2007 at Shelby, MT: