Denny Desoutter, 'Small Boat Cruising' 1964, described the Mystic:
Designer Robert Tucker, Builder C>E>Clark (Cowes) Ltd (though some were home built), Thames tonnage 3 tons, Displacement, 2,060lb, LOA 21'4", LWL 17'.0", Beam 6'10", Draught 2'6", Ballast 600lb Sail area 155 Sq ft, with genoa 195 Sq Ft.
Mystic had a flush deck (though some had a small doghouse over the main hatch) which then dropped to a full width cockpit which extended to the transom, but with quite a small footwell.
Later a few were built in GRP, though I never saw one. Becoming quite rare now, having gone the way of most plywood boats.
The spec from Oldharry is correct as far as it goes. The Mystic is a single chine ply boat and is a flush decker. The characteristics which distinguish the yacht are the port holes are lozenge shaped and there may be one or two on each side.The bilge keels are built up of laminated timber with the ballast as 300lb cast iron keels bolted to the lower ends of the two bilge keels.There is no central ballast as in the silhouette or only other flush decker of Tucker design of this length, the Debutante.
Behind the keels towards the stern is a skeg, this may house a propeller shaft if the boat was fitted with an inboard (usually a watermota sea-urchin air cooled 3.5 h.p.) If an outboard was fitted this was in a well in the rear compartment.
The yacht is built of 3/8" high quality marine ply to B.S.1088 and is framed with I think Oregon or British Columbian pine. The mast is aluminium, housed in a galvanised iron tabanacle. All the fittings are galvanised and on the whole are still available from Davy & Co. If you don't know the number of your boat and it is a yard built one, you will find the numbers stamped in approx 1" high numbers on the underside of the floor boards or on the underside of the main or fore hatches, or on the keel right up at the bow under the shelves. I have been rebuilding one for the last year, any help I can give is no problem however general info about the boats is hard to come by. They are well designed and constructed in my opinion, and are a real 60's classic which are now rare.