The change of ephemeral gully headward erosion, gully-wall collapsing and deep-cutting erosion were quantified in the three stages of initial-phase, metaphase and anaphase.

A little stream of Knowledge trickled slowly through a deep worn gully.

Then, when Westport was scarcely out of sight, as we were trying to cross a deep muddy gully - another feature of prairie experience that afterward became too familiar to us - the cart stuck fast.