Dr. Reed, Dr. Walton, and Dr. Macagno wrote a fascinating paper on the origins of argument mapping. Apparently, Richard Whately, in 1836, was the originator of argument mapping. It was an incredible accomplishment.

As depicted below (with Rationale™), his original map used a “mountain (or tree)” design. It is still, with some variations, the conventional visual language used today. This design does, however, have some deficiencies. For example, there is always an unnecessary number of premises to reflect the lines of inference. And there is no defined pattern for reading the map from start to finish. The second map reflects a transitive inference path visual language as an alternative. [I am not addressing the transitivity questions contained within the argument.]