The room occupied by Galileo at the Selve communicates by a winding staircase with an upper terrace where he used to spend the nights in watching the stars. Here he discovered the spots on the sun and its revolution upon its axis, the ring of Saturn, the phases of Venus and Mars and their rotation round the sun, and here he wrote his treatise on the planets, the history of the sun-spots and other works. He loved the country and country pursuits, and his favourite recreation was working in the garden; very proud was he of his skill in pruning vines and fruit trees and he used to declare there was no better preservative of health than living in the open air. A wall at the back of the villa with a peculiar curve is said to have been built under his supervision. If two people whisper in a low voice at the ends each can hear the other distinctly. In 1614 Filippo Strozzi died at Barcelona and Galileo left the villa he loved so well. About the same time a Dominican friar, Tommaso Caccini, preached a sermon in Santa Maria Novella denouncing Galileo and all professors of mathematics. “Mathematics are of the devil,” he exclaimed, “and mathematicians as the authors of all heresies should be driven out of every state.” Monks and theologians denied the existence of the Medicean planets, some even insisted that the moon shone by her own unaided light.[78] From the broad terrace of the villa the view is magnificent, “you see half the world” the peasants say. Below is the glinting river fringed with tall poplars and on the summit of the hill on the opposite bank stands the huge Medicean Villa Artimino surrounded by ilexes. To the right is the picturesque old bridge across the Arno connecting Ponte a Signa with Beata Signa; further away still the grey machicolated walls and towers of Lastra a Signa stand out against the fruitful green plain. In the far distance Poggio a Cajano rises like a giant above the village clustering round it, and the trees look like shrubs beside the villa where Francesco I, and his second wife, “the infamous Bianca” as her brother-in-law called her, died on the 19th and 20th October 1587.