Lilting through the floorboards

''An old hotel,'' the captain said. ''Condemned. You can't get through the fence. And the pier's breaking up in the waves.'' We first saw it from the water, as the fishing boat hovered offshore while we trolled for sea trout. The trout did not bite, even though Cousin Henry was humming Schubert's ''Die Forelle.'' But we were bitten and smitten by the rambling, barnlike building, white in the September sun.

The beat of dance bands from the '20s, the rhythmic crunching of rocking chairs along the verandas, the tinkling of ice in freshly squeezed lemonade, even the offshore breeze in the single pine by the sea wall, wafted across the waves into the ears of my mind. Stutz Bearcats, Duesenbergs, and Maxwells gleamed from the stables beyond the courtyard. From every window peered a tanned girl in a white lawn dress about to descend for a dabbling of feet in the foam; or a white-haired man in a linen jacket about to go for a hike on tneDbeach, while discussing affairs of state with an elegant lady already unfurling her white parasol; or a trio of children about to escape from their governess to explore the dunes and then plunge into the waves. . . .

Our fishing boat moved on, in pursuit of elusive trout.

But a year later we returned, this time by land. It was true, the fence was formidable. Even Cousin Henry's nephew Warren, who at 10 should have been ready to scramble up, was daunted. But he wasn't a fence-climber, wall-scrambler, tree-scurrier, cliff-scaler. He is a whiz at math, marvelously good-natured and cooperative, but not a reader, not a dreamer, not an explorer.

I am. My childhood spilled over into the tops of the tallest pines, up the bluffs where the swallows nested, over old walls to check if the figs were ripe, and into abandoned houses. Not that I like heights - stepladders are objects I climb to change overhead light bulbs only when there is no one around I can trick into climbing them for me. But I am fond of pursuing whatever adventure might wait beyond.

So in a few minutes Cousin Henry, Warren, and I had found a spot to leave the battered car near the beach a couple of miles farther along.

A light rain was falling, but rain has never daunted Cousin Henry, so off we sprinted over the dunes and rocks and onto the sand. Sandpipers were daunted neither by the rain nor by the translucent jellyfish lolling in the shallows. Did the children of old also stalk the sandpipers down the beach, as if pursuing Zeno's Paradox, and dare to swim among the jellyfish? Had they leaned from the pier to catch crabs with nets - while the yachts of the likes of J.P. Morgan's Corsair were anchored offshore?

Warren wondered if we hadn't gone too far from the car.

As we approached the weatherbeaten structure, jogging along wet sand, over the eroding strata of gray clay, we saw that the eyes of the windows were hollow. The main roofs and dormer triangles and chimneys seemed intact, but the long, low verandas and other additions were caving in. The porch pilasters leaned at peculiar angles.

We circled the building. Cousin Henry was intrigued but kept his distance. Warren hung back. I was already stepping over the broken boards and shattered glass of the verandas.

''Careful!'' Cousin Henry was calling after me. ''For goodness' sake, don't go any farther!''

I paused on the threshold of the grand ballroom. Swallows soared from nests around the eaves, and a large spider dangled from the spot where the chandeliers must have hung. Festooned wih webs, a broken tea cart was installed in a hole in the floor. A scarf of maroon velvet tatter wrapped the neck of a disconnected pipe. Vines pushed through cracked plaster. Warren picked up an oyster shell, perhaps thrown onto the dissolving swatch of carpet by an old hurricane.

''It's dangerous in there!'' Cousin Henry called from the threshold. ''You might fall through!''

''I'm walking only where it's solid,'' I called back from the bandstand area. True, the kitchen back there did not look substantial, and beyond an overturned sink was a cavern dark as an oubliette. I circled along the edges, straining to hear an overlooked orchestra play ''Sailing Along on Moonlit Bay'' while the ladies in chiffon floated over the tiles and their escorts in white dinner jackets fanned themselves with damask napkins and checked that the upward twist of their mustaches had withstood the dance.

Warren did not hear any music. But he was already walking gingerly after me along the edges. We met at the bottom of the grand staircase. It looked sturdy enough, despite the wandering banisters. But I told him to wait for me to check it out. I did.

Step after splintery step, glass crunched underfoot. Not knowing if there would be much floor above. . . . I could see the sagging ceilings and the empty windows. . . . Scraps of wallpaper flapped in the wind. A frog jumped from a puddle on the landing.

Warren was behind me, beside me. Cousin Henry was warning something from downstairs, but the wind was banging a shutter somewhere. We tested the corridors, carefully, very carefully, but we explored to the ends, and from their thresholds checked the rooms.

From every window: a view of the sea, the pier, distant fishing boats lost in the mists. No Corsairs or skipjacks or pungies plying the offshore winds, but maybe that was only because we could not see them for the rain.

''I believe there is a pirate ship out there,'' Warren whispered.

''We'd better organize all cannons at the windows then,'' Cousin Henry whispered back, as he tiptoed gingerly behind us. ''And fortify the pier.''

''I'll climb up onto the roof with my telescope,'' Warren said, ''to keep you guys below posted on their advance. Here's a trapdoor!''

''No,'' I said, ''that's going too far. The view from the veranda is sufficient.''

''But can't you hear their rigging flapping, and the trumpets, and the swish of their cutlasses in the wind?''

''In that case,'' I said, ''we had best ask the band to tune up, and distract them with music and dancing.''

But Cousin Henry was already hoisting Warren up on his shoulders, up through the trapdoor to the roof. He hauled himself up next and disappeared into the sky.

I don't like rooftops, but what could I do but somehow chin myself up and through the splintery frame, the better to see the ship, the better to hear the band . . . ?