Strumenti di misura del Signor Carlo Theti “huomo di grandissima pratica circa l’operationi matematiche et di più esperienza in le fortificationi”

Abstract

During the XVI century a more mature formalization of mathematical rules as well as of the instruments for measuring and representing a city and its surroundings is set up. Since the early seventies of the sixteenth century the first shape of the proportional compass is recorded thanks to Carlo Theti, a military engineer; the above mentioned compass can be considered a precursor of Galileo Galilei’s best known geometric and military compass. In his work Discorsi delle fortificazioni Carlo Theti describes another new instrument for measuring distance, height and depth more easily without attributing it a specific name. This contribution tries to show how these measuring instruments work, wich proved to be very effective.