This ought to be good:
They wrote alternate chapters, Burroughs as "Will Dennison," a New York bartender, Kerouac as "Mike Ryko," described as "a 19-year-old, red-haired Finn, a sort of merchant seaman dressed in dirty khaki". While many of Burroughs' thematic interests and later obsessions – drugs, violent death, hustlers, gay sex, broken glass – are apparent from an early stage, the young Kerouac held his own against the chilly sage. "There was a clear separation of material as to who wrote what," Burroughs told his biographer, Ted Morgan. "We weren't trying for literal accuracy at all, just some approximation. We had fun doing it. Of course what we wrote was dictated by the actual course of events – that is, Jack knew one thing and I knew another. We fictionalised. The killing was actually done with a knife, it wasn't done with a hatchet at all. I had to disguise the characters, so I made Lucien's character a Turk."