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Rh motion of projectiles, and other themes connected with dynamics, the strength of beams, the possible finite velocity of light, the harmonic vibrations of strings, the explanation of concords and discords, and similar subjects, some of them only occurring as digressions.

The MS. was completed in 1636, but the Inquisition had forbidden any of Galileo's work to be published, even reprints of his previous books, to which no exception had been taken. He tried to find a publisher outside Italy, but the presence of Scheiner in Germany and the fear of opposition from him and the Jesuits caused one project after another to be abandoned, until finally Elzevir produced the work at Amsterdam in 1638. Galileo pretended that this was pirated from a MS. copy, in order to observe the letter of the embargo laid on him by the Inquisition.

As soon as the MS. had been completed he projected a fresh series of problems, including the subject of Percussion, and also resumed his plan of determining longitude at sea by observation of Jupiter's satellites. The negotiation with Spain had dragged to an end in 1632, but in 1636, hearing that a prize of 30,000 scudi was offered by Dutch merchants for a sure method, Galileo offered his plan through his friend Diodati at Paris; using this means in order to keep the officials of the Inquisition in ignorance of what he was doing. His sight was failing, and when the Dutch Government sent him a gold chain as a sort of retaining fee, he was found in bed totally blind. He refused to keep the chain, fearing that he would be unable to complete his calculations. As a matter of fact his "Ephemerides" were afterwards completed, but owing to a series of accidents they were not published for two centuries.

His last astronomical discovery before his sight failed altogether was the explanation of what is called the