LIMOGES is not a city that calls for a long stay, but it is worth a look for a magnificent train station and the craft industries that made the city a household name: enamel in the Middle Ages and, since the eighteenth century, china, including some of the finest ever produced. If these appeal, then the city's unique museum collections - and its Gothic cathedral - will reward a visit. But it has to be said that the industry today seems a spent tradition, hard hit by recession and changing tastes among the rich. The local kaolin (china clay) mines that gave Limoges china its special quality are exhausted, and the workshops survive mainly on the tourist trade.