Nikola Tesla Books
as supporting documents for the application in which he sought American citizenship, which he obtained in 1891.
After passing his final secondary-school examination, Tesla returned to Gospic, where he fell ill again and spent nine months bedridden. Although his father wanted Tesla to devote himself to the priestly vocation, he had to give in and promise his sick son that, as soon as he recovered, he would send him to study engineering in Graz. In his autobiography Tesla describes his arrival in Graz:
When I recovered, my father sent me to the Technical University in Graz, which I had chosen as one of the oldest and best of its kind. I eagerly awaited that moment, and thus I began my studies under favorable auspices and with firm faith in complete success. My preparation was more than average, for which I have to thank the favorable circumstances and the good guidance of my father. Already at that time I spoke several languages and had read many books from various libraries, so that I learned many, more or less, useful things. To this was added the fact that for the first time in my life I could choose those subjects in which I had the greatest interest. Freehand drawing no longer troubled me; I was firmly resolved to surprise my parents, and during the first year I worked without interruption from three o'clock in the morning until eleven at night, day after day - indeed even on Sundays and holidays. My fellow students did not take the matter so seriously, so it is no wonder that I was first among them. In the first year I passed nine examinations. The professors were of the opinion that I deserved more than the highest grades. Full of flattering testimonials, I returned home for a short rest, convinced that I would be received at home in triumph. I was very disappointed when I saw how my father accepted my acquired honors lightly, without particular interest. This crushed my ambition; only later, after my father's death, did I learn the true reason, when I found a mass of letters that my professors had written to my father, advising him to forbid my further studies, because there was a danger that, due to excessive work, I might ruin my health. After that I devoted myself mainly to the study of physics, mechanics, and mathematics, and spent all my free hours in the library. I was seized by a mania to bring every undertaking I began to completion, which was often associated with very great difficulties. Thus once I began to read the works of Voltaire, but to my
