Well, new to me at least. The Huntington Library in California recently updated their website with a collection of Andrew Russell photos that were in the collection of J.B. Clough. Clough was the chief engineer on the USMRR Aquia Line and others. I mentioned him in a blog posts here, here and here.
Of the new photos in this collection were several showing engines by the Alexandria roundhouse and a new view of the Potomac Creek Bridge.
The freight car in the upper corner is interesting, but otherwise the photo did not provide any new significant information. It does show the rock face under the bridge very clearly. By the look of the terrain, I believe that is the southern abutment. So this photo is looking west.
It is fun when you discover some new material.
If you are wondering why no there were no blog updates over the weekend, I was on a trip to Cresson, PA to railfan with some NTRAK friends. This trip has become an annual rite to celebrate Jake's birthday. He likes it cold and snowy and he got his wish. It was frigid, but we had fun. These videos give you an idea of the conditions we had.