One of the great pleasures of visiting San Francisco is a stroll along this city’s historic Fisherman’s Wharf. Here visitors can peer down at the fishing crafts riding in the calm water, or pause to watch fishermen mending a net. Most of the boats in view belong to a "third generation" of fishing craft, which have made history at Fisherman's Wharf. From the days of the Gold Rush until the turn of the century, the San Francisco fishing fleet was composed of lateen-rigged sailboats. They were copies of the craft which the Italian fishermen knew in their native land. Green was the prevailing color of the tiny boats, and the name of a patron saint appeared on the hul