Hello all

How long can you keep tobacco in the bowl, after having lit it, smoked it a bit and let it go off?
Because I occasionaly meet that problem, especially when I take my pipe with me to work or to a gathering, I can't finish the whole bowl. So after I return back home, I would smoke it. But at times I would completely forget about my pipe for a few days at a time (with my busy life style!), so when I wanna smoke it again, I would then just throw off the old tobacco and refilling it anew. I have never tried to smoke tobacco which has remained there for a few days!
Would that be ok, or should I just replace it?

Would it be dryer if I smoke it? would it be bad (healthwise, tastewise, qualitywise...any other-wise?!)
For how long can previously lit tobacco stay in the bowl?