ONE'S feelings are not completely unmixed. To anyone truly caught in the romance of the rails, the best use of a train station is as a train station. And yet from all accounts the new Or say Museum (n'ee Gare d'Orsay) in Paris is a splendid example of what architectural preservationists like to call ``adaptive reuse.'' The railway station whence trains once departed for Orl'eans, Nantes, and Bourdeaux has been turned into a major art museum tracing the cultural explosion of the 1848-1914 period.
Seen simply as a place to hang pictures, the museum, which opens next week, does a number of important things: It allows, for instance, a much larger number of Impressionist works to be displayed than did the Jeu de Paume, and will be a bridge between the Louvre and the Paris Museum of Modern Art.
Beyond that, the building itself, a product of the same era as the art it now houses, will be an object on display, with the grand halls and soaring ceilings that say as much about human aspirations of the 19th century as the cathedrals do of those of the Middle Ages.
Recycling a great structure into a museum is, however, hardly unprecedented in Paris. The Louvre, after all, was once a royal palace; where tourists today gawk at Old Masters, Henri IV once galloped his horses. It has been one of the particular charms - and strengths - of Paris as a city to find ways to include ordinary people in extraordinary public spaces. At the Mus'ee d'Orsay, the French have done it again.