>Flint nodules seem to have been used quite extensively for building in the
>chalk country of southeastern England.
>
I spent several years in the south of England, two in Brighton on the coast
and many, many of the older (19th c.) structures were either built with
flint nodules or faced with them, Brighton College is a good example.  Flint
was also used for paved walkways and some small streets, and to top walls
with the more jagged edges up.  By the way the same thing was done with the
bottoms of broken wine bottles>