For those in whom train whistles and the rhythmic clacking of wheels through the night stir memories, the time to take that last sentimental journey may be near. The administration has decided the nation can no longer afford to subsidize the railroad link to the past. Without that subsidy, the few remaining long-haul passenger trains will go the way of the Royal Blue, the Twentieth Century Limited and the Super Chief.

Secretary of Transportation Drew Lewis told Congress earlier this week that he feels more strongly about cutting the funds for Amtrak than he does about any other part of his department's budget. "Amtrak is a monument to bureaucracy," he said. "It's a mode of transportation from a bygone day." This hardheaded analysis is wrong in only one respect. Amtrak is a monument not to bureaucracy but to nostalgia.

A lot of hopes have been dashed since Amtrak was created a decade ago on the theory that trains could prosper if only they were well run. A decade of experience and steadily rising deficits has proved several things: namely, that some people will ride the trains if service is good and prices are competitive, but not enough will to offset the costs of operating them, except in a few urban corridors and commuter areas.

In another year, with a different national mood, an administration might decide to prolong the experiment, or part of it, on the chance that motorists would return to the trains once gasoline prices got high enough. Congress may still decide to go that way. But it is hard to justify spending tax dollars on long-haul passenger trains when so many necessities are being cut.

The trains, of course, could come back. The rails will still be there; the administration seems to be having second thoughts about its original intentions to starve Conrail. And views of what mode of transportation is appropriate do change; this city, within the last 25 years, dismantled the streetcar tracks to make way for automobiles and then dug up the streets to put a similar set of tracks beneath them.

But don't count on a resurgence of those long-haul trains. Once gone, they are even less likely to return than are the Washington Senators. Remember them?