Cob Why the coast?

[Benjamin Graham]

I don't believe most cob buildings were built along the coast.  I never would
have thought there actually were some until a structural engineer living in
Devon England working on repairing cob buildings told me there were.  He
didn't seem to know any specifics, but I thought he mentioned they used more
exposed rock to shed windblown water, ie horizontal rain. 
       You could write the Devon Earth Building Association and they would
probably have some clues.
Yours
Ben Graham