Contents of the Manuscript
and its relation to the Discorsi

The Codex 72 of the Galilean Collection (Collezione galileiana) in theBiblioteca Nazionale Centrale in Florence is a miscellaneous manuscriptcomprising 241 folios of various sizes, carrying folionumbers from 1 to 196. The first 32 folios of the codex contain severaldifferent writings not included in this electronic representation.

The bulk of the manuscript (from folio 33r to folio 194r), which iscovered by the electronic representation, holds drafts (texts, drawingsand calculations) written by the hand of Galileo or of his disciples MarioGuiducci and NiccolòArrighetti, mostly pertaining to the theorems on motion published inthe Discorsi. The texts and translations of these theorems and their proofs are included in the electronic representation (translation of Henry Crew and Alfonso de Salvio, Macmillan, New York 1914). They are accessible through a list of propositions containing also links to all folio pages related to the respective theorems. Within the translations of the proofs links are added indicating deductive conditions used by Galileo at the respective places.

The fragments on motion and mechanics are neither dated nor does theirorder in the Codex correspond to the chronological sequence of their composition.Galileo's notes belong to very different periods of his life, the earliestdating from around 1600, the latest from the period in which he preparedthe Discorsi for their publication in 1638. The selection and orderof the folio pages in the present Codex 72 of the Galilean Collection isa result of the complex history of the manuscript.

Besides the fragments on motion, this part of themanuscript also includes three short letters to Galileo.