December 10, 2013

Science isn't everything

HAVE YOU EVER EXPERIENCED the tendency of your boat to sheer away automatically from shallow water when you’re running parallel to a submerged bank?  The oldtimers used to call it “smelling the land” and regarded it with awe, but it can actually be explained scientifically as a hydrodynamic manifestation of Bernoulli’s law.

Not all hull designs do this equally well, apparently, but those that do are a boon to skilful skippers when they find themselves nosing up a strange narrow channel. They simply let the boat have its head, letting it wander from side to side of its own accord and naturally finding the deepest water.

Science doesn’t explain everything, however.  D. Phillips-Birt, the well-known designer, says there was a lot of scientific thought put into determining the best waterline length of the old J-Class boats.  Some of the best brains in yacht design occupied themselves with the problem of whether it should be 80 feet or 87 feet, to take best advantage of the rule.

“The argument was fought with resistance curves, plotting on logarithmic scales, and treatises of great erudition,” he wrote.  And when the lofty discussion was at its height, it was L. Francis Herreshoff who brought everybody down to earth.

Scorning the scientific approach, he pointed out that it was worth noting that the success of recent J-Class yachts was in exact mathematical proportion to the number of sails delivered to each by the sailmaker.

Whereupon C. P. Burgess, who designed a duralumin mast for Enterprise, admitted:  “ . . . there are a great many variables which influence the speed of yachts. Perhaps one of the most important and least regarded is what the skipper had for dinner the night before.”

Today’s Thought
Equipped with his five senses, man explores the universe around him and calls the adventure Science.
— Edwin Powell Hubble, Science

“What’s the celebration in the clubhouse?”
“My husband did it in one.”
“What? A hole in one?”
“No, he managed to hit the ball in one.”

(Drop by every Monday, Wednesday, Friday for a new Mainly about Boats column.)

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