Theater of Machines, Volume II

unspeakable costs were built—almost exactly, especially those waters that were conducted into the city of Rome. For because people in ancient times noticed the excellent utility of such water conduction, no expense, however high it might amount to, was spared, so that everyone intended to serve the common good with such, and to attain eternal praise and fame. But the measurement or libration leveling (as all authors agree) is the first beginning of all water conduction, whether it be for springing fountains or for the drive of ceaseless movement of various millworks and similar artificial water structures, which are driven by the falling, rising, or flowing forward of the water. And such measurement or libration can happen from the place to which we want to conduct such water, or at the place where the same arises, through the sighting of instruments by the straight line, as is shown in the following figure with both Greek letters δ. φ. or with both Latin letters B. C. Where then such water-level or Corobates leveling instrument is placed and fastened, a plumb-line is placed upon it, as is in common use among the

Libration leveling is a beginning of water conduction.