Oh, sorry about that. Well, it's edification for anyone who needs to know.
Broadly speaking, the first volume featured many letters that Burroughs addressed to Ginsberg, often with intent to seduce. They're raucous and funny, like Naked Lunch. The letters in the second volume are addressed to a wider array of correspondents. Guys like Ginsberg and Kerouac drop off and others like Brion Gysin and Antony Balch make frequent appearances. The concerns are dramatically different. Burroughs writes about the cut-up, scientology, interactions with publishers and little mags. You (Graham) will dig that there are some family letters. Bill Morgan, who edited vol 2, deliberately followed the m.o. that Oliver Harris established for vol. 1, so there's continuity in the editorial approach.
I'm only part way through but it's been really enjoyable to read. If I was blurbing the book I would say with complete sincerity that it's a must-have.
Burroughs' falling out with Kerouac is well-known (they came to dislike one another's political views, particularly over Kerouac's support of the Vietnam war). Another broken friendship that I wonder about is Greg Corso, who helped Burroughs assemble Naked Lunch
, but who from the 60's on had little to do with him. Any indication in the letters as to why Corso and Burroughs didn't get along?
Incidentally, the change in tone among the letters between the 50's vs. later 60's and 70's isn't that surprising, there was also a major shift in Burroughs' writing style, themes, and worldview between the time that he wrote Naked Lunch
and his later work. His early works were unsentimental, often intentionally disgusting acccounts of drug use and sexuality, the later writings were more sentimental and self-celebratory.