I believe the Shanks data for Ontario are rather messy and not fully reliable. He lists a lot of places all over Ontario (about 250) which according to him follow the same time zone history as tz zone America/Nipigon I think considerable local research is needed to sort out pre-1970 Ontario time zone history. Shanks describes 116 different rule sets for Ontario. I attach screen shots from klm files on Google Earth showing how the towns listed for Ontario by Shanks are locally distributed. Label (5) represents the Shanks rule set which corresponds to TZ rule set America/Nipigon, while according to TZ the zone America/Nipigon is a tiny area. On 17.01.20 10:01, Paul Eggert wrote:
On 1/13/20 8:15 AM, Jeffery Nichols wrote:
I was also wondering whether anyone on your team has more data about what towns were part of America/Nipigon.
I got that data from my printed copy of the Shanks International Atlas. It contains hundreds of place names in Canada but does not sort them by time zone region. I just now looked in Shanks (4th edition) for place names beginning with "A" with the same time zone history as Nipigon (Shanks calls this Canada's region 35), and found the following:
Alfred Algoma Mills Algonquin Almonte Alvinston Appleton Apsley Arden Armstrong Armstrong Station Aroland Attawapiskat Auburn
The book has latitude and longitude for each of these entries. It would take some time to transcribe all this info (including B-Z) for all of Canada. Also, Shanks partitions the world into many more regions than tzdb does, because he doesn't have the 1970 cutoff that tzdb does. So he partitions Canada into 253 regions and there could be other Shankian regions that share Nipigon's post-1970 time zone history and would thus fall under America/Nipigon in tzdb.