It was his intention to obtain a tutorial position at the University. An appointment to Bern was at first again hindered by certain obstacles which he would probably have overcome if he had applied himself energetically to attaining his goal. He finally received his appointment, but exercised his duties for only a very short time, as Zürich now opened her arms to him. In 1909 he accepted the position of Professor extraordinarius there for theoretical physics, and soon assembled a grateful audience about himself. Nevertheless, during the earlier stages of his professorship he found it difficult to suppress a longing for the quiet, unexcited life of his patent-office work, in which he seemed to have had a still greater degree of independence. In 1911 he accepted a new appointment as Professor Ordinarius to Prague, which offered him more favourable emoluments as an inducement. In the autumn of 1912 he returned to Zürich as a Professor at the Polytechnic, and in the early part of 1914 he was drawn into the strong magnetic field of the northern capital; he arrived at the Spree, and has, since then, lived among us. He is now a Swiss by nationality, a world citizen by conviction, and, professionally, a member of the Berlin Academy and attached in a lecturing capacity to the University. Here he perfected his works on relativity, ending in the superlative elaboration of the theory of gravitation, the beginnings of which stretch back to the year 1907. He had spent eight years in a concentrated effort of severe thought to bring it to completion, and perhaps centuries will be necessary before the world will gain a complete perspective of all the consequences of his theory. For the theory asks us to brush aside habits of thought that have claimed an hereditary position in pre-eminent minds. One of the foremost physicists, Henri Poincaré, had confessed as late as 1910 that it caused him the greatest effort to find his way into Einstein's new mechanics. Another whole year passed before he gave up his last doubts. Then he passed with flying colours into Einstein's camp, and recommended Einstein's appointment to the Professorship at Zürich, in conjunction with the discoverer of radium, Madame Curie, in an exuberant letter which may add its note of appreciation here: