The most famous of the serpent mounds is the effigy, 1254 feet (382 metres) in length measured along its curves, in Adams County, Ohio. An observation tower now gives visitors an overall view of this great earthen reptile, but when Squier and Davis made their fine survey of it and William Pidgeon inspected it on the instructions of De-coodah, they could appreciate it only by walking from the tightly curled tail and along its seven loops to the jaws, which are opened wide in the act of swallowing an egg.
Pidgeon, who had seen other serpent mounds further west, had been told of them by De-coo-dah that when the worshippers of reptiles were reduced by the fortunes of war, and compelled to recognize the sun, moon,and heavenly bodies as the only objects worthy of adoration, they secretly entombed their gods in the earth-work symbols which represented the heavenly bodies.
He therefore interpreted the Ohio effigy of serpent and egg as an astronomical symbol. Scholars today are inclined to agree with him. In 1975 T. M. Cowan of Kansas University contributed a paper, ‘Effigy mounds and stellar representation’, to A. F. Aveni’s book, Archaeoastronomy in pre-Columbian America, in which he suggested that effigy mounds and other ancient earthworks were designed on the pattern of stars and constellations. A traditional image of lunar eclipse in Asia is the Moon being swallowed by a serpent, and this may be part of the meaning of the Ohio mound. But the seven loops of its body and the tightly winding tail are seen by Cowan as representing the seven stars in Ursa Minor and their annual rotation round the pole star. The connection, as he says, is ‘teasingly close’.
The serpent and other such earthworks may have been used for astronomical observation and for recording astrological lore, but there is something else about their sites that cannot so easily be explained. At first sight, there seems to be no obvious reason why the Ohio serpent mound should have been placed where it is. Other neighbouring hilltops are higher, with grander views, or with greater areas of flat surface, or more accessible for the people carrying up the earth. Yet there is a certain perceptible quality to the place that the serpent seems to have been designed to express. For the serpent is the ancient symbol of the Earth spirit: the vital current that identifies the earth as a living creature, whose – magnetic centres are associated all over the world with strange atmospheres, hauntings and apparitions as well as the sacred sites of early Man.
Stories of the weird experiences of locals and visitors have been told about the great serpent mound. One such report, of a literally hair-raising nature, was written for Fate magazine (June 1977) by a sociology professor, Robert W. Harner. As he stood alone on the serpent’s head one clear, sunny day in autumn, something happened that threw him into ‘the coldest, most abject, hopeless terror I have ever experienced.’ Something like an evil, elemental force was present, and as Harner felt it move towards him he saw its shape in the pattern of swirling leaves cast up around it. As the leaves surrounded him, dancing ever closer, he felt himself begin to faint with horror — and then suddenly the spell was broken. The energy vortex died down, the leaves became still and Professor Harner returned to his car, promising himself that he would never venture onto the mound again. ‘Perhaps’, he concluded, ‘they built their mound on that particular hill because very special things happen there.’
The ancient serpent symbol is found throughout central America.