Billy Corgan is sitting in almost total darkness, talking about the end of things. One of them is his interest in writing pop songs. The other is his band, the Smashing Pumpkins.

"I've taken pop songwriting as far as it can go," the singer-guitarist declares. He points at a copy of the band's new album, Machina: The Machines of God, on the table in front of him. "This is pretty much the end of the line."

Corgan, who turns thirty-three in March, is wearing black from chin to toe: turtleneck sweater, boots and pants with a long flap hanging from the waist, creating a sari-like effect. The only light in the room - an empty loft in a warehouse on the West Side of Chicago, Corgan's hometown - comes from a ¯ickering candle at his elbow and a weak winter sun rapidly setting outside the window. But it is enough to illuminate the grin on Corgan's pale, round face."This is so typical of me," he says, laughing. "After our first album, Gish, came out, a lot of the press said I couldn't write a pop song. Which I took as a great insult. 'Yeah, I'll write pop.' Lo and behold, I become the best alt-pop writer of my generation."

There is a self-mocking lilt in Corgan's voice, enough to assure you he's being at least partly ironic. But he's got tunes to back up the boast: "Today," "Disarm," "Bullet With Butterfly Wings," "1979," to name a handful. He's also got the numbers. The Pumpkins' 1993 hit, Siamese Dream, and their '95 two-CD set, Mellon Collie and the Infinite Sadness, have sold a combined 8.8 million copies. Even 1998's Adore, a solemn affair and a relative commercial disappointment, has gone platinum. "But I don't have anything more to say within the idiom of pop," Corgan claims. "I don't know where else to go."

As brick walls go, Machina is a feast of hard-rock candy: the fuzzy bark of Corgan's and James Iha's guitars in "The Everlasting Gaze" and "Age of Innocence"; the sharp choruses and Jimmy Chamberlin's galloping drums in "Stand Inside Your Love" and "Wound." There is also art rock - the ten-minute epic "Glass and the Ghost Children" - and narrative conceit. Machina is an intricate Corgan discourse on, among other things, faith, need, resurrection and the alchemical powers of rock & roll. Imagine Pink Floyd's The Wall rebuilt in the battered image of grunge - heavier, punkier, self-involved but not self-pitying.

Corgan shakes his cleanshaven head in genuine indecision when asked whether this, his last pop-song album, is also to be the Pumpkins' sayonara. "I go back and forth," he admits. "I'm fully convinced that bands, in the modern era, are not good for more than three records. We should have stopped after Mellon Collie, but we didn't.

"So we're back with a vengeance," he says with evil glee. "See, now we're pissed off, so you get the full weight: 'We shoulda quit, you wanted us to quit, but we didn't. We're gonna make you pay.' "