Interesting Book: Sundials: Their Theory and Construction (publ. 2024-04-24)

I found this very interesting book at a second-hand store:

Sundials: Their Theory and Construction

Albert E. Waugh

Copyright 1973

ISBN 0-486-22947-5

Sundials are, of course, not quite as common as they used to be, but they make for an interesting way to better understand the relationship between the sun and the tracking of time. There are a lot of interesting nuances to this such as the implications of latitude and longitude, the calculations of angles, understanding time zones, and the "equation of time". Today I started a little project to make a simple horizontal sundial on top of a square wooden board that I found.

One thing that threw me off for a while was that the book tables assume Alaska is UTC -9 time zone, which was the case back in the 1970s, but actually now most of the state is UTC -8. This fact, which had never seemed strange to me before, is actually rather interesting because I realize that, with the Daylight Savings adjustment included, my Local Standard Time is almost 2 hours different than Local Apparent Time, i.e., the time based on when the sun crosses my meridian. So here in Fairbanks the sun is now setting very late (about 10pm) but doesn't rise until almost 6am, and the brightest, warmest part of the day is in mid-afternoon.

In principle I like the design of the equatorial sundial the best, but a small horizontal sundial seems simplest right now for construction, deployment, and storage.