His sojourn in Rome had sadly pulled him down. On his return home, in July, 1877, he had lost his voice and was greatly reduced. But in October of the same year he once more roused himself for a journey to Italy. The object of the previous one was to follow his hero in yellow and faded historic papers, but this time the task he had set himself was to pursue the tracks of Galileo in all the cities and places in any way connected with his memory. The result of these travels was an article in the _Deutsche Rundschau_, No. 7, 1878, “On the Tracks of Galileo.” In this paper Gebler again dispels some clouds in which Galileo’s previous biographers had enveloped him. We in these less romantic days are quite willing to dispense with the shudder at the stories of the dungeon, etc., and are glad to know that Galileo was permitted to enjoy a degree of comfort during his detention not often granted to those who come into collision with the world. “On the Tracks of Galileo” was Gebler’s last literary work. His strength of will and mental powers at length succumbed to his incurable malady. The mineral waters of Gleichenberg, which he had been recommended to try, did him more harm than good. He wrote thence to a friend, “I am in a pitiable condition, and have given up all hope of improvement.” Unfortunately he was right. He had overtasked his strength. His zeal for science had hastened his end, and he may well be called one of her victims. His last days were spent at Gratz, where his boyhood had been passed, and he rests beside his only brother. Both were the pride and joy of their father, now left alone. In appearance Karl von Gebler was distinguished and attractive looking. No one could escape the charm of the freshness and originality of his mind, in spite of constant ill health. The refined young student, with the manners of a man of the world, was a phenomenon to his fellow-workers in the learned world. We have heard some of them say that they could not understand how Gebler could have acquired the historian’s craft, the technical art of prosecuting research, without having had any special critical schooling. The writer of these lines will never forget the hours spent with this amiable and, in spite of his success, truly modest young man in his snug study. The walls lined with books, or adorned with weapons, betrayed at a glance the character and tastes of the occupant, while a pendulum clock dating from the time of Galileo recalled his work on the first observer of the vibrations of the pendulum to mind. He always liked to wind up the venerable timepiece himself, and took a pleasure in its sonorous tones. When I once more entered the study after his death, the clock had run down, the pendulum had ceased to vibrate, it told the hour no more. PREFACE TO THE GERMAN EDITION.