PHIL BOLGER REPLIES

It's hard to imagine anybody looking at a Herreshoff 12 1/2 without smiling except maybe Nathaniel Herreshoff himself. Yet while the record suggests that he was a cold-blooded calculating machine, consider the series of names he gave his personal boats: Alerion, Swiftsure, Delight, Helianthus, Dilemma, Sabrina. None of them are what I'd expect from a man who, it is said, never smiled. Another anomaly is the 12 1/2.

It's ironic that this modest boat is captain Nat's living monument. His engineering feats are as dead as so many triremes, yet the little sloop that deceptively looks as if a hundred other men might have designed it, but which, in fact, only Nat Herreshoff could turn into a masterpiece, sails on as Bill Harding's Doughdish (SBj #15). This fiberglass replica is a greater tribute to Herreshoffs memory than any museum piece. The first time I ever saw one of those, I remember thinking at once that Captain Nat would have nodded curt approval of the boat and the reasoning behind it.

There is, of course, no way to duplicate the intricate shape of the 12V2 in sheet plywood. I haven't tried. One reason I've traced off the full body plan for each end of the boat is to emphasize that the shape has to be dramatically different to accommodate the way plywood behaves. The hollow flare to a full deckline in the bow has to go. And to balance that, both to the eye and for the sake of the action of the boat, the stern is narrower. Neither end will be as handsome as the original when seen in three dimensions with shadows and reflections.

To compensate, I made her lower-sided, increasing the angles of the raking ends. The sleeker profile is supposed to distract the eye from the coarse sectional shape. It will work from many angles, though not all. This will be a very good looking boat indeed, as long as there isn't a Doughdish next to her.

Buoyancy, Ballast & Keels

The reduced freeboard means the plywood boat will get her rail down sooner than the Herreshoff. I made the cockpit coaming higher to get back some of the height. There is plenty of buoyancy in the end compartments to float the boat. Some of the original boats didn't have this. Waldo Howland's A Life in Boats has an account of a 12 1/2 that filled and sank while racing; the way he treats the incident suggests that it wasn't extraordinary. People used to be more casual about boats that could be dangerous if mishandled than we're expected to be now. They treated foundering potential about the same way we do the consequences of 40- knot speeds and meatchopper propellers.

The plywood boat is a little stiffer (has more initial stability) than the 12 1/2 partly because she doesn't have the hollow garboards, whose buoyancy down low takes away some stability. A good part of the fin here would be hollow with plywood walls, but free-flooding. This adds some ballast effect, though I would design it that way mostly to eliminate a solid mass of timber that would swell and shrink and to make it quicker to build. It allows short keel bolts, saving the long bores that many home builders have trouble with. The ballast casting shown is 100 pounds lighter than the Herreshoffs. My thought was to save that much cost, but I'm of two minds about it now. I know of many boats that were improved, sometimes dramatically, by giving them more ballast, and very few that were helped by reducing ballast. I'd want to think about putting the 100 pounds, or more, back in a finished design.

The square "garboard" of the plywood boat adds some wetted surface. In theory, this should make the boat slower in light air, but I've grown skeptical about reductions in wetted surface. The resistance is real enough, but it's hard to reduce it without increasing some other drag. If you cut down a boat's effective lateral plane to reduce wetted surface, and as a consequence end up with a bigger leeway angle so that the boat starts to go through the water more crabwise, the trade-off is often a bad one. The late Howard Chapelle tried to tell me this many years ago, but didn't convince me at the time because I thought he was over-concerned with maximum, rather than average, speeds.

A sailboat keel is often thought of as analogous to an aircraft's wing, but there is a significant difference. All aircraft have a reliable power source (even a plane with a dead engine is powered by gravity -highly reliable!), whereas a sailboat ,has to operate efficiently with power input close to zero. At any rate, it's possible that the big flat keel forced on this design by the structural material is not bad for her performance.

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