From Bill Briggs, Chairman of the Section in 1975-76:
When I became chairman, the Newsletter Editor was using various picture items. I proposed to the Council that we make a logo that gave us an identity and they said, "Fine, you do it".
The head of Art Dept (Bob Frye?) assigned Ralph Heitman to do the art work. I crudely sketched the positions of the elements to show with the Arch and Ralph produced the result. Our Newsletter Editor used it — and it has been used since. I expect that Ralph drew it referring to pictures he had available.