IS-02DEC10 Waiting by the Metro

I drew this impulsive sketch today, while waiting for a car inspection, at a local gas station lot. It close to the metro railway station, which railway's support system you see here. I really wanted to draw that railway structure.
I started drawing the left side to anchor things, then threw some perspective out the window when I started drawing the railway structure. The impulse to draw this sketch was obviously to capture the railway structure, the rest be damn. So there you have it. Actual Escher-like dimensionality by pure mistake. Genius! Thank you! Sure.
Obligatory Explanation:
Impulsive Sketches, by its nature and origins is prone to, and will sometimes contain errors, scratches, smudges, happy/un-happy mistakes, possible stains, etc. You have been warned.
This same sketch will be posted on dA's group for Impulsive Sketches. Look it up next time you visit DeviantArt. Thanks for dropping by, and have a great art time