The chorobates, described by Vitruvius in Book VIII of the De architectura, was used to measure horizontal planes and was especially important in the construction of aqueducts.

Similar to modern spirit levels, the chorobates consisted of a beam of wood 6 m in length held by two supporting legs and equipped with two plumb lines at each end.

According to Isaac Moreno, this vertical design is way more efficient when it comes to optical leveling and makes more sense from a topographer's point of view.

And few years later, when Juan de Lastanosa published “The Twenty-One Books of Engineering and Machines" of Gianello della Torre”.

In his "Ars Mensoria" series, Isaac Moreno Gallo recreates practical demonstrations of Roman topographic instruments using his own replicas.