mutuli architectural brackets, as is denoted in the following figure with R and S. Then the instrument of the water level will be placed on the end, as is denoted with T. In such a beam, a notched spindle should be inserted, as denoted with α, which may turn a small wheel (denoted with β outward). On such a spindle, a little cord or string is pulled and fastened from one instrument to the other, as is denoted in the following figure with S and M. If you turn such a small wheel, you may align the instrument straight with the water. But to ensure that the beam on which such an instrument stands also stands perfectly upright, you may align it through the plumb weights, directed from the outermost part of both supports, denoted with V and X, where such hang at equal distances from one another, as is denoted with Y and Z. But in addition to such an instrument, you may have another prepared for yourself according to the Italian manner, like a little box of thinly beaten brass, prepared in four sides or directed octagonally, as is denoted in the following figure with S. And such an instrument is quite convenient and customary for surveying in the discovery of such long lines, and much more convenient than the common sights or amulfes a type of leveling device, denoted with λ. The points of the sights are denoted with θ. But for better understanding, look with diligence at the following figure:

The pieces of the chorobates or

the water levels.

Dioptra, or small water level. A.