ὑδροφαντική
From LSJ
πολλὰ δ' ἄναντα κάταντα πάραντά τε δόχμιά τ' ἦλθον → and ever upward, downward, sideward, and aslant they went
English (LSJ)
(sc. τέχνη), ἡ, the art of discovering water, Gp. 2.6.1; also ὑδροφαντικά, τά, ibid.
German (Pape)
[Seite 1174] ἡ, sc. τέχνη, die Kunst, verborgenes Wasser zu entdecken.