In the fairy tale The Swan’s Nest, a poetic description of Denmark, Hans Christian Andersen mentions three swans that flew out of that “nest.” “The swan, with the strong beating of his wings, scattered the twilight mists, and the starry sky was seen, and it was as if it came nearer to the earth. That was the swan Tycho Brahe. Another swan beat with his wings upon the marble crag, so that it burst, and the forms of beauty imprisoned in the stone stepped out to the sunny day, and men in the lands round about lifted up their heads to behold these mighty forms.” That was Andersen’s description of the sculptor Bertel Thorvaldsen. “A third swan spinning the thread of thought that is fastened from country to country round the world, so that the word may fly with lightning speed from land to land.” These are the words about the Danish physicist Hans Christian Ørsted.
Like many of his contemporaries, he was an extremely versatile scholar — philosopher, chemist, and pharmacist. Ørsted studied and taught extensively — it was to him that the University of Copenhagen owed the establishment of its scientific school of physics. A hundred years later, the seeds sown by Ørsted would give the sprouts, as the university would teach Niels Bohr. And Ørsted will be honored for more than this. Hans Christian Ørsted is remembered in the history of science as the discoverer of the magnetic effect of electric current. In 1820, he showed at a lecture the heating of a wire with electricity from a voltaic pile. Next to it on the table was a compass, and when Ørsted closed the circuit, the compass needle flew sideways. The discovery made Ørsted a famous physicist and national hero with the unit of magnetic field strength named Ørsted in his honor. And he was and remained an enlightener and did much for the young talents, including his full namesake, Hans Christian Andersen. This explains why Andersen praised Ørsted so poetically. But no one wants to remember the mutual admiration society — Andersen and Ørsted are equally brilliant.