Subway Sketching

I'm currently swamped in work I can't show (of course I had to go and sign those non-disclosure agreements) so here's a small subway sketch.

The thing I like most about urgently drawing an unsuspecting model (who can get off the train anytime while I draw) in an uncomfortable postion (easels are a drag to carry around) in a moving vehicle (which doesn't allow for fine details) is that all I can rely on is shape and line weight to convey volume. A valuable exercise.