BIDENTAL
BIDENTAL an erection on a spot where lightning had fallen. The name is derived from the sacrifice of a young sheep (bidens) by the haruspices at the place. Sometimes, from the resemblance of the structure to the mouth of a well, it was called puteal, as in the case of the puteal Libonis or Scribonianum at the eastern end of the Forum Romanum (Hor. Ep. 1.19, 18; Sat. 2.6, 35; Pers. 4.49), and another in the Comitium (Cic. de Div. 1.1. 7; Liv. 1.36, &c.). [PUTEAL] When lightning had struck a spot, it was held necessary condere fulgur, either publice or privatim, according to the nature of the place. If a man had been killed by the lightning, it was not lawful to burn the corpse, but he was buried on the spot. (Plin. Nat. 2.145.) Everything which had been scorched or scattered by the lightning was solemnly collected by the pontiff (who was at a later date assisted by the haruspices) and piled up with a low muttered prayer. (Schol. on Juv. 6.587: cf. Lucan 1.607; Acron. on Hor. A. P. 471.) A bidens was offered, and a small enclosure, neither paved nor covered, was built around the heap, and was further surrounded by an exterior wall, bearing the legend fulgur conditum. Many inscriptions of this kind are still extant, and at Pompeii a bidental has been discovered, of which the outer protection is formed by eight Doric columns. (Mazois, Ruines de Pompéi, t. iv., pl. ii. iii.) It was not allowed to tread this locus religiosus, or even to look into it. (Schol. Pers. 5.27; Amm. Marc. 23.5.)From Horace (A. P. 471) it appears to have been believed that a person who was guilty of profaning a bidental would be punished by the gods with frenzy. (Cf. Marquardt, Röm. Staatsverw. 3.252-3.)
[A.S.W]