With all their joys and inspirations the experiences in Italy remained but a short episode. Einstein resolved on a new tour, which was not without a professional purpose. He made a pilgrimage to Switzerland with the intention of studying mathematics and physics at the Zürich Polytechnical Institute. But he was not to be successful in his first effort to gain entrance. The conditions of entry required a standard in descriptive sciences and modern languages that he had not yet reached. So he turned to Aarau, where he was allowed to extend his knowledge with the help of excellent methods at the Canton school. Even it the present day Einstein talks with extreme enthusiasm of the organization of this model school that corresponds in rank approximately to a German Realgymnasium (or an English Grammar School). There was nothing to remind him of the continual manipulation of the sceptre of authority at the Luitpold school barracks; he easily obtained his leaving certificate, and now the portals of the Zürich Polytechnicum were open for him. He himself was probably not aware that he carried a marshal's baton in his own mathematical equipment. But, in looking back, we come across astounding things. For it is a fact that even in the pupil at Aarau problems had taken root that already lay in the vanguard of research at that time. He was not yet a finder, but what he sought as a sixteen-year-old boy was already stretching into the realms of his later discoveries. We have here simply to register facts, and to abstain from making an analysis of his development, for how are we to trace out the intermediate steps, and to discover the sudden phases of thought that lead a very young Canton pupil to feel his way into a still undiscovered branch of physics? The problem that occupied him was the optics of moving bodies, or, more exactly, the emission of light from bodies that move relatively to the ether. This contains the first flash of the grandiose complex of ideas that was later to lead to a revision of our picture of the world. And if a biographer should state that the first beginnings of the doctrine of relativity occurred at that time, he would not be making an objectively false statement. The ambitions of the youth by no means reached these flights of imagination, for whereas the latter signified the coming power of his wings, he himself set a modest goal. He wished to become a schoolmaster, and imagined that in choosing this career he was allowing his hopes to run high. This was in conformity with the esteem in which he held the status of teachers. In the Zürich Technical School there is a section equipped as a department for preparing teachers, and in this Einstein studied from the age of seventeen to the age of twenty-one, perfectly satisfied with the thought of sitting, not on the pupil's bench, but at the master's desk, and of exercising a beneficial if limited influence as a preceptor of the young.