Engraving of a canal lock in Vittorio Zonca's, Novo teatro di machine et edificii per varie et sicure operationi (1607) which describes and illustrates a host of mechanical achievements of his time, and provides a realistic interpretation of Leonardo Da Vinci's design of the walls and foundations of the lock at San Marco. Three small boats are ready to leave the lock, an oval shaped brick basin, just as the miter gate is opened by workmen straining at the windlasses. The miter gate follows Leonardo's design, but Zonca also showed a single-leaf gate at the other end of the lock. Hydraulics is a topic in applied science and engineering dealing with the mechanical properties of liquids.