Two more responses on the lim-1 question.......DMD ________________________________ Subject: Re: history of lim-1 Date: Wed, 18 Jul 2001 22:41:21 -0500 From: Clarence Wilkerson I recall a paper by a student of Milnor's, R. Yee (sic) used to be the reference. I think this included the case of larger towers as well. Yee was a faculty member at the U. of Hawaii when I was there. Clarence Wilkerson ____________________________ Subject: Re: responses to lim-1 Date: Wed, 18 Jul 2001 16:33:02 -0400 (EDT) From: Claude Schochet It is certainly the case that Steenrod was the first to calculate a non-trivial lim^1. Jerry Kaminker and I wrote about "generalized Steenrod homology theories" with this in mind. It was a very specific computation, meant to illustrate the difference between Cech homology and Steenrod homology. However, there is no sign in that paper of lim^1 being a derived functor of lim (the right words hadn't even been invented yet) nor is there any systematic treatment. It is simply an obstruction group. Milnor's 1961 paper deals with Steenrod's theory, and he produces a short exact sequence to compute H_*(inverse limit of X_i$ where the X_i are finite complexes and X = inverse limit X_i is a compact metric space. This of course involves lim and lim^1. (For some years Jerry and I had the only copies of this paper and were the "publishers", so to speak.) There is no mention of the 6 term sequence there. Milnor's Pacific J. paper (1962) that is most familiar to topologists deals with the dual situation - computing h^*(infinite CW cx) in terms of the finite subcomplexes. So I believe that Brayton is correct - Roos gets credit for the 6 term sequence for abelian groups. Thanks!