I was thinking after I read Joe's "shiver" posts that my Allied Seawind
32 will shake in rhythm if the wind strikes the mast sideways at certain
wind speeds. If one lies on deck with head near the mainmast and looks
up one can actually see the mast "pumping".

Now, it is said that whales can hear very low frequencies. Picture a
sailboat as an oddly-shaped base fiddle sitting in the water. The mast
pumps and the rigging moans so I wonder if whales can hear this and
might this be the reason some yachts are attacked by whales.

Wilbur Hubbard