From: Andy Lipscomb <AndyLipscomb@decosimo.com> Sent: Friday, January 20, 2006 12:39 PM
Thanks for doing all that work. As you can tell if you are reading the tz list, I was doing that work independently (and published it before seeing your email) but I double-checked my work by comparing it to yours. First, Shanks says Vincennes and Indianapolis differed in many ways before 1964. For example, he says Vincennes observed DST in 1946 and from 1956 through 1963. I assume you merely copied Indianpolis's table to Vincennes for time stamps until now, which wouldn't be quite right. Second:
In addition to the section above, the new zone will need to be added to the zone.tab file. Vincennes' location is +384042-0873058.
My proposed patch had +384038-0873143 which is fairly close. (The LMT figures also diverged, presumably because of the coordinate difference.) My latitude and longitude are from Shanks. I'm not sure how Shanks (or anyone else) decides where Vincennes "is", given that one arc second of latitude is only 31 meters or so.