This is the first block, with a big left
margin. At the end of this block is a left float which should be
square. Text that follows this box should flow to the right of the
float or go below it; no text should be on the left of the float.
This is the square left float.
This is the second block. It is sized so as to
be just narrow enough to fit in the gap to the left of the
float. Text should not want to be to the left of the float, since
it is a left float in flow, so instead all the text should just
move below the float.