It's a rare day I come across an ad for something I actually own, especially when it's as rare as this gem. The Sunwatch is a pocket sundial with a compass to orient yourself properly with the sun. I just happen to have found one of these when I was cleaning out my dad's house and as far as I know, it belonged to my grandfather.
Originally invented for the use of Boy Scouts they were sold in various technical publications as well from the early 1900's through the late 1920's. My particular one was made around 1921 by Outdoor Supply Company, who bought the patent from Ansonia after WWI. The construction is cheap by 1920's standards, stamped sheet metal with a transfer face and plastic case German compass but compared to the cheap China world we live in today it's actually made to withstand the rigors of outdoor life. I didn't get an outside shot of mine but suffice it to say that it's been well worn for being in someone's pocket for years.
So to figure my time I live in Jacksonville, Fl which is on the list and indicates I need to add 28 minutes correction, it is also March 11th and I need to add another 10 minutes for a combined total of +38 minutes correction. If we look at the face of the Sunwatch you'll see there's markings along the top arc of the compass that indicate minutes correction in either plus or minus. So all I have to do is point the compass about at the 40 mark on the right and that would do it. I set the