Kristine was first, with similar responses received shortly afterwards from Greg Friedman and Randall Helmstutler...........DMD _______________________________________________________ Subject: Re: two postings Date: Fri, 16 Jan 2004 12:54:45 -0700 (MST) From: Kristine Bauer Hi, The still photos appear on p. 166 of : Bredon, Glen E., Topology and geometry. Graduate Texts in Mathematics, 139. Springer-Verlag, New York, 1993. xiv+557 pp. ISBN: 0-387-97926-3 Kristine Bauer > ___________________________________________________________ > > Subject: spinner spanner > Date: Thu, 15 Jan 2004 08:51:15 -0500 (EST) > From: James Stasheff > > The fact that the fundamental group of O(3) is Z/2 > can be illustrated (literally) by the contortion with a water glass > rotating wrist and arm through 720 degress > I once saw a series of still illustrating this > perhaps in Scientific American > > anyone have any reference? > > .oooO Jim Stasheff jds@math.unc.edu > (UNC) since retiring from UNC hanging out at U Penn > jds@math.upenn.edu > \ ( 146 Woodland Dr FAX:(215)-573-4063 > \*) Lansdale PA 19446-1437 > > http://www.math.unc.edu/Faculty/jds > _____________________________________________________________