When Schall was brought up for trial there was, at his side, another Jesuit named Ferdinand Verbiest, a native of Pilthem near Courtrai in Belgium. He had come out to China when he was thirty-six years old, and was first engaged in missionary work in Shen-si. In 1660 he was summoned to Pekin to assist Father Schall, and in 1664 was thrown into prison with him. In the court-room, Verbiest was the chief spokesman, for Schall, being then seventy-four years of age and paralyzed, was unable to utter a word. The charges against the old missionary had been trumped up by a Mohammedan who claimed to be an astronomer. They were: first, that Schall had shown pictures of the Passion of Jesus Christ to the deceased emperor; secondly, that he had secured the presidency of the board of mathematics for himself in order to promote Christianity; thirdly, that he had incorrectly determined the day on which the funeral of one of the princes was to take place. It was an "unlucky" day. Verbiest had no difficulty in proving that the accused had been ordered by the emperor to be president of the board of mathematics, and furthermore, that he never had anything to do with "lucky" or "unlucky" days. The charge about the pictures of the Passion was admitted, and that may have been the reason why, in spite of the eloquence of Verbiest, who was loaded with chains while he was pleading, Father Schall was condemned to be hacked to pieces. In this trouble, however, the Lord came to the rescue: a meteor of an extraordinary kind appeared in the heavens, and a fire reduced to ashes that part of the imperial palace where the condemnation was pronounced. The sentence was revoked, and the missionaries were set free. Father Schall lingered a year after recovering his freedom. When Kang-hi came to the throne in 1669, an official declaration was made denouncing both the trial and the sentence as iniquitous, and although Schall had then been three years dead, unusually solemn funeral services were ordered in his honor. His remains were laid beside those of Father Ricci. The emperor himself composed the eulogistic epitaph which was inscribed on the tomb. Schall had given forty-four years of his life to China, when at the age of seventy-five, he breathed his last in the arms of Father Rho, who, like him, was to hold a distinguished position as mathematician in the imperial court. Rho had preluded his advent to China by organizing the defense of the Island of Macao against a Dutch fleet. He had new ramparts constructed around the city; he planted four pieces of artillery on the walls, and when the Dutchmen landed for an assault he led the troops in a sortie and drove the enemy back to their ships. In his "Promenade autour du Monde" (II, 266), Baron de Hübner gives an enthusiastic description of the Jesuit Observatory at Pekin.