With all of the technological sophistication available today, it's fascinating to think about the tools and data available to early solar architects. Previously I discussed Whit Smith's solar tool , a homemade device using solar cotangent diagrams published in 1938.
The first commercially-available solar tool (that I am aware of) was made by the Libbey-Owens-Ford glass company beginning in 1951. I recently purchased one as a gift for a friend, and took a few pictures before sending it along.
Earlier, in 1946, Libbey-Owens-Ford had patented a slide-rule type of device: "Method and Apparatus for use in Designing Solar Houses". It was never produced as far as I can tell.