In less than a year, sweet Maria Celeste had said the last psalms for him. She died April 1, 1634, at thirty-three years of age, leaving Galileo heart-broken; "a woman," he said, "of exquisite mind, singular goodness, and most tenderly attached to me." He went to work on another book, but he said, pathetically, "I hear her constantly calling me!" Beautiful spirit, that will forever shed a halo around the name of Galileo Galilei! In the summer of 1636, he completed his "Dialogues on Motion," and sent it to Leyden for publication. The next year he made his last discovery, known as the moon's librations. The house at Arcetri had become dark and lonely. The wife of Michelangelo, her three daughters and a son, had all died of the plague. It was doubly dark, for Galileo had become hopelessly blind, "so that this heaven, this earth, this universe, which I by my marvellous discoveries and clear demonstrations had enlarged a hundred thousand times beyond the belief of the wise men of bygone ages, henceforward for me is shrunk into such a small space as is filled by my own bodily sensations." His last work was a short treatise on the secondary light of the moon. "I am obliged now," he said, sadly, "to have recourse to other hands and other pens than mine since my sad loss of sight. This, of course, occasions great loss of time, particularly now that my memory is impaired by advanced age; so that in placing my thoughts on paper, many and many a time I am forced to have the foregoing sentences read to me before I can tell what ought to follow; else I should repeat the same thing over and over." He had planned other work, but death came on the evening of January 8, 1642, eight years after Celeste left him. His beloved pupils, Torricelli and Viviani, and his son Vincenzo, stood by his bedside. He desired to be buried in the family vault of the Galilei in Santa Croce, at Florence, and the city at once voted a public funeral and three thousand crowns for a marble mausoleum. But the church at Rome prevented, lest the pernicious doctrine that the earth moves, should thereby have confirmation. He was therefore buried in an obscure corner of Del Noviziato, a side chapel of Santa Croce. A century later, March 12, 1737, in the presence of the learned men of Italy, with great ceremony, the bones of Galileo were removed to a new resting-place in Santa Croce, and buried with his beloved friend, Viviani. An imposing monument was erected over him. The truth finally triumphed, as it always does. The works of Galileo, in sixteen volumes, are no longer prohibited, as they were in his lifetime. SIR ISAAC NEWTON. [Illustration: SIR ISAAC NEWTON.] In the same year, 1642, in which Galileo, sad and blind, went away from the earth, Sir Isaac Newton came to make his home upon it.