The Yawp of Reason THE RAINBOW STORIES <i> by William T. Vollmann (Atheneum: $22.95; 543 pp.) </i>

The rainbow in the title of this collection of pieces by William T. Vollmann refers to the author’s use of different colors as codes for different chunks of human life and human spirit.

It is a private and hermetic conceit, one of a good many in Vollmann’s writing. More immediately, though, the “Rainbow” suggests the extraordinary range and fire of the author’s style.

The pieces in “Rainbow” extend from fiction to spooked poetic narratives to intoxicated reportage to reportage so meticulously uninflected as to suggest Dada. Vollmann manages a whole wardrobe of voices: ornate, inconsolably bare, romantic, and something resembling messages on computers. A single author’s voice would imply synthesis and connection; Vollmann’s pieces are rafts foundering in the divided waters of a world blown apart.

He writes with a fierce and bright-hued sensibility, perpetually inflamed. The disconnection and threat of modern, or if you like, postmodern life--Vollmann stands in our avant-garde--goads him to the farthest possible remove from the minimalism that reigned in our fiction a decade ago, and still has important voices. He is the most maximalist of writers. “Ladies and Red Nights” is a series of notes on Vollmann’s nights spent touring San Francisco’s Tenderloin, inventorying the different kinds of sex offered, talking to prostitutes and strippers. He is punctiliously detailed; writing down what each experience or encounter costs him. (A peep-show slot machine, 25 cents; an hour or two with a call girl, $150.)

From the blur, one or two women emerge. There is Brandi, the exuberant extrovert who has pricing down to such a fine art that she is able to cost out each conversation with Vollmann. Having told him she loves to eat, she charges an additional 50 cents to disclose her favorite dish: spaghetti.

There is Christina, bolstered by eight or nine steady customers but diligently patrolling her three Tenderloin blocks each night. “The Tenderloin does not seem to be so much good or bad as constricted,” Vollmann writes.

It is an odd phrase, that. Equally odd is a sudden burst of pathos amid his note taking: “The sorriness of what she had to do for 10 years was almost enough to make one believe in the Divine--there must be something else.” We realize that Vollmann is up to something other than realism, with its hunger to know what is.

Vollmann’s is a deflected hunger. His focus is not his subjects but his own act of looking at them. He tries out different voices--objective, sentimental, dislocated--as if one of them just might help him break through. I am cut off but I am trying, he seems to say.

There is an equivalent dandy-in-spite-of-himself quality to “White Knights,” another bit of urban reportage. Here, though, there is the ghost of a connection, and it is an unlikely one. His subject is the San Francisco Nazi Skinz, a gang of skinheads.

They are rough, all right. Anthony, for example, polishes his boots obsessively. “People are gonna see their reflection right before I kick them in the face,” he explains. Curiously, though, the tone is elegiac, almost tender. The Skinz are washed up; most have left town. Vollmann uses a past tense. “They used to go into bars and find fighting, punch people in the face when they didn’t like the way they looked (being Nazis, they were conscious that appearance is everything).”

Nazism is simply the nearest rebellion at hand. He has a devastating thought, watching the Skinz in their hangout. They remind him of pictures from Buchenwald. “Stubble-crowned, tattooed, naked, and angular.”

In “Blue Yonder,” Vollmann mixes reportage on the city’s street people with a vein of Expressionist nightmare. It is a semi-fiction; his portrait of drifters and bums is counterpointed by his account of a schizoid madman, Zombie, who moves among them stunning them with his cane, pouring Drano into their mouths and decapitating them. It is a horrifying piece, claustrophobic in its intensity and detail.

In “The Indigo Engineers,” again a mix of fiction and reporting, Vollmann writes of the Survival Research Laboratory. It consists of three engineers who design and build terrifying machines with scythe blades, flame-throwers and sensors. They star in theater-of-cruelty spectacles. Rabbit-like and human-like robots are released; the killing machines go after them and tear them bloodily to pieces.

The piece takes the form of interviews with the engineers, who are passionately matter-of-fact about their job. Intercut with these is the story of Pawel, whose family was taken to Gestapo headquarters in Poland when he was a child. An officer gave him an apple; the family was suddenly and arbitrarily released. And Vollmann weaves the two stories together.

Are they purposely building cruelty into the machine? he asks the engineers. “They are what they are: Various,” one replies. “You have a Walk and Peck Machine, you have a Spiked Roller Machine whose function is to spike and roll.” And Vollmann thinks of the Gestapo. “I see a Guarding Machine, an Execution Machine and an Apple Giving Machine.”

It is a powerful, splendidly controlled satire on the amorality of a super-technological society. In another story, in which he sets an IRA man who blows up a department store alongside a laboratory worker who kills test mice, the control is looser and less effective.

“Scintillant Orange” is a wonderfully worked-out version of the biblical story of Shadrach, Meshach and Abednego in Nebuchadnezzar’s fiery furnace. Here, Shadrach is the ideological zealot; Abednego is a nerdy scientist experimenting with fire-resistant clays to see if he can make himself a jacket that will save him; and Meshach is a comically besotted aesthete who looks forward to the furnace. He adores the color orange.

It is a wild and dazzling pastiche, with a vein of iron running through. Other stories--one tells about a band of ancient Indian Thuggees; in another, Vollmann imagines himself as the Holy Ghost in love with a violet-haired woman he thinks of as St. Catherine of Siena--are equally flowery and lush, but without the iron; they amount to little more than insistently decorative posturing.

Vollmann is uncontainably sentient. Not a stone in his landscape but delivers a sermon; a gaudy one.

The sentience is untiring, and also tiring. Vollmann is like a painter praised for his pulsing colors. That is not quite all that a painter must be praised for. Writing is a phone-call to a listener. Perhaps the listener is imaginary, perhaps the listener is God. The writer writes under the threat that the listener may hang up at any moment. Even God may hang up.

Vollmann lacks the faculty of listening even while speaking; of listening for the click that signifies both art’s vulnerability and the glory that flows from it. He sings in a shower stall; the voice is prodigious, the echoes tremendous. Is anyone else at home?

Perhaps not, but Vollmann is there, thrusting himself full-tilt into the pain, the horror and the fugitive loveliness of our time. His yawp is more barbaric than Whitman’s and deafer, but we are short of yawpers these days, and we need him.