The Face-mesa was built without symmetry to convey two different human 'faces'. Obviously it cannot be symmetric because the original positive in high contrast, as shown below, gives a thing without any resemblance to human face. The geniality of Mr. Ignatius was precisely to recognise a priori, without graphic clue, that my Art-lines (below to the right) correspond, once reversed to NEGATIVE as in above image, to a perfectly proportioned human face. View-point in South-West, ground level.