βορβόρῳ δ' ὕδωρ λαμπρὸν μιαίνων οὔποθ' εὑρήσεις ποτόν → once limpid waters are stained with mud, you'll never find a drink
P. and V. μάτην, P. ἀλόγως, V. ματαίως.