THE RAINBOW STORIES <i> by William Vollman (Atheneum: $22.95; 543 pp.) </i>

“He writes with a fierce and bright-hued sensibility, perpetually inflamed. The disconnection of and threat of modern, or if you like, postmodern life--Vollman stands in our avant-garde--goads him to the farthest possible remove from the minimalism that reigned in our fiction a decade ago. . . . His yawp is more barbaric than Whitman’s and deafer, but we are short of yawpers these days, and we need him.”