| {Boston } | | | | | | | | +---------+---------------+----------------+-------------+--------+------+----+--------+------+-----------+ The chief characteristic of her construction is the employment of Tobin bronze for her plating (save the upper row of plates, which are of steel), and her centreboard, also of bronze, is made of two plates set apart with ribs between, the space of 2-1/2 in. being filled with cement; the structure weighing 7,750 lbs., and being operated from the cabin by means of differential lifts, capable of raising 6 tons. 'Jubilee' is of unusual design and construction; her body is wide and shallow, with a fin attachment carrying about 40 tons of lead at a depth of 13 ft. below the water's surface, and to increase the lateral plane she has a centreboard that works through the fin and its bulb of lead, exposing surface enough to ensure most excellent windward work, dropping about 8 or 10 ft. below the bulb. 'Pilgrim' is an out-and-out fin-keel yacht, the largest vessel of that type ever built. Like 'Jubilee,' she is broad and shallow of body, the fin being of a separate construction, and this with its bulb of 15 tons weight was attached to the vessel in New York, the hull having been built in Wilmington on the Delaware. She carried her bulb 23 ft. below water, which gave her good stability and power to hold her course when sailing to windward; but with her, as in some measure with 'Jubilee,' they did not represent any authorised, well-tested type of yacht, and though their performances were interesting and highly instructive, they did not fill the mind of the true yachtsman with glowing satisfaction, seeing that the work that was in hand was one of national importance and required designs of equally high character. The middle of July found all four yachts in sailing, if not racing, trim; their owners scrupulously avoided contact with each other; each claimed unheard-of speed and other noble qualities; and each felt that his craft was that on which would rest the honour of defending the America Cup. It was soon found that the booms of 'Colonia' and 'Vigilant' were not satisfactory; they were not stiff enough to hold the sail where it should be to ensure a flat set, and when swung off their weight was found to list the yacht too much, both of which difficulties were to be expected in spars of their length and diameter (100 ft. long by 16 in.). Hollow booms of different construction were tried. Those where the spar was sawed lengthwise and the core dug out, then glued and trenailed together, were found to be the best. Booms of highly elaborate construction made for 'Colonia' and 'Vigilant' were tried and found unsuitable. They were built up of long staves, having double skins which were well glued and fastened, and weighed less than half the solid spar; they were 30 in. at slings, 18 in. at after, and 15 in.