Mario Guiducci
[1] In 1618, the year Guiducci became consul of the Accademia Fiorentina, a particularly bright and long-lasting comet was seen in the skies over Europe, and soon afterwards an anonymous pamphlet was published in Rome entitled "De Tribus Cometis Anni MDCXVIII".
'[4] While Guiducci and Galileo were working in the Discourse, a second anonymous Jesuit pamphlet appeared in Milan - Assemblea Celeste Radunata Nuovamente in Parnasso Sopra la Nuova Cometa (sometimes wrongly attributed to Giovanni Rho).
The debate continued when, in Perugia later in 1619, Grassi published a reply to the Discourse in La Libra Astronomica ac Philosophica under the pen-name Lotario Sarsi Sigensano.
Guiducci concluded with an attempt to reconcile experimental evidence with theological arguments, but firmly asserted the primacy of data gathered through observation.
Mario Guiducci would be allowed to lecture in his Academy, carrying out the duties of his office there, and even to publish his Discourse on Comets without "Lothario Sarsi" a person never heard of before, jumping upon me for this.
And even if the entire Discourse were the work of my pen - a thing that would never enter the mind of anyone who knows Guiducci - what kind of behavior is this for Sarsi to unmask me and reveal my face so zealously?
In the autumn of that year Guiducci went to Rome to see if he could gain any preferment under the new Pope, and he regularly frequented the circle of Cardinal Francesco Barberini.
Guiducci was also the intermediary through whom Galileo communicated to his colleagues in the Accademia dei Lincei the manuscript of his response to Francesco Ingoli's 1616 letter challenging Copernican ideas, De situ et quiete Terrae contra Copernici systema Disputatio.
[17] In the Spring of 1630, during the quarantine imposed on Florence by Grand Duke Ferdinand II to prevent the spread of plague, Guiducci was one of four patricians placed in charge of administering the special provisions in the quarter of Santa Maria Novella.
[19] Bartolotti's plan was to cut a new, straight course for the river, avoiding the series of bends in its lower course which slowed it down, causing it to burst its banks.
Guiducci and other owners on the west bank appealed against the proposal, arguing that the engineering solution offered would not in fact lead to improved drainage.
To support his case, Guiducci asked Benedetto Castelli to send a copy of his Treatise on the Measurement of Flowing Water to the magistrates who were to resolve the matter.
[20][21] Galileo had just finished the manuscript of the Dialogue Concerning the Two Chief World Systems and deployed some of the theoretical arguments about acceleration from this text into his opinion on the Bisenzio.
He argued that the speed of water flow was determined by the relative elevation, rather than by the length, of the distance it travelled, supporting Guiducci's view that a new cut making a shorter course for the river would be useless.
In 1632, when Galileo was required to go to Rome to face the Inquisition, he left Guiducci in charge of his personal affairs, and of forwarding correspondence with his daughter, Sister Maria Celeste.
[24] After Galileo's sentencing to house arrest in 1633, Guiducci continued his literary and genealogical contacts with former members of the Accademia dei Lincei, which had disbanded on Cesi's death in 1630.
