The Trisectors (Spectrum)

Per someone else's mention elsewhere in the thread, it looks like Dudley eventually published a book based on it: https://www.amazon.com/Trisectors-Spectrum-Underwood-Dudley/... and also https://www.amazon.com/Budget-Trisections-Underwood-Dudley/d... (whose title was probably inspired by De Morgan's "A Budget of Paradoxes").

Edit: I think the second book there is actually just the first edition of the first book, and the title changed for the second edition.