This is ONE OF 2 responses to Vol 9 John 14 ("Twisting and Turning")...
I don't know the answer to that one but in the movie SAN FRANCISCO Clark Gable tells Greer Garson that water drains out of bathtubs from right to left west of the Continental Divide and left to right east of it (or something similar). After much observation I believe it has to do with the construction of the bathtub and not its local.
Suzanne! What a great ponarv question!!