Which band?

[aplummer at raye-atm.rz.uni-frankfurt.de]

I have a seemingly simple question to ask that I can not quickly answer.
I have often digested a vector with a RE with a single site within
the vector.  After running the gel, instead of seeing 1 single band, I 
observe 2.  I conclude that one of the bands is uncut vector, while the 
other is cut.  My problem is that I do not know which is which
(top/bottom).  Any help with this seemingly simple question would be
greatly appreciated and would help expedite a rather difficult sub-
cloning procedure.


-Al