Caesar\'s siege of Gergovia

[Currahee Chris]

I do not know much about this siege but am curious as to why Vercingetorix did not press or pursue Caesar's forces once Casear decided to pull back. Could it be that the Roman army was retreating in good order and it would have proved too costly for Vercingetorix? Was Caesar's retreat more along the lines to "fight another day" or were they threatened to be overrun?

Thanks
CC