Shivas:
There are a pretty good number of golf architecture historians and analysts who do feel that Macdonald may've gotten the idea for the Biarritz swale from NB's 16th green. He certainly did mention going there to look at the course in 1906. And I think most good architecture analysts and historians are pretty sure the famous Biarritz hole over the Bay of Biscay in Biarritz France did not have a swale in its green or before it. However, I do remember reading somewhere in an old article within the last decade that there may've been another green on that course in Biarritz France that did have a very large swale in it like the 16th at NB, so who knows where Macdonald got that idea? By the way, Macdonald did say in his autobiography that he made up to thirty sketches and such of what he considered to be important architectural features from abroad. Those were apparently the architectural sketches and drawings that Hugh Wilson mentioned in a letter in March 1911 that Macdonald had shown him during his two day visit to NGLA in early March 1911.