). An instrument for determining the slope of an
aqueduct and the levels of the country through which it was to pass. From the description
given of it by Vitruvius, it appears to have differed but very slightly from a common
carpenter's level, which consists of a straight rule supporting a perpendicular piece, against
which hangs a plumb-line. The chorobates
had two perpendiculars and
plumb-lines, one at each end, instead of a single one in the middle (Vitruv. viii. 5, 1).