Notes

Heinrich Rudolf Hertz was born on February 22, 1857 in the German port city of Hamburg. He was the firstborn of five children. His mother was Anna Elisabeth Pfefferkorn, the daughter of a physician. His father was Gustav Ferdinand Hertz, an attorney who became a Senator. His paternal grandfather, a wealthy Jewish businessman, had married into a Lutheran family and converted to Christianity. Both of Heinrich’s parents were Lutherans, and he was raised in this faith. His parents, however, were more interested in his education than his religious status. Aged six, Heinrich began at the Dr. Wichard Lange School in Hamburg. This was a private school for boys run by the famous educator Friedrich Wichard Lange. The school operated without religious influence; it used child-centered teaching methods, taking account of students’ individual differences. It was also strict; the students were expected to work hard and compete with one another to be top of the class. Heinrich enjoyed his time at school, and indeed was top of his class. Unusually, Dr. Lange’s school did not teach Greek and Latin – the classics – needed for university entry. The very young Heinrich told his parents he wanted to become an engineer. When they looked for a school for him, they decided that Dr. Lange’s alternative focus, which included the sciences, was the best option. Heinrich’s mother was especially passionate about his education. Realizing he had a natural talent for making things and for drawing, she arranged draftsmanship lessons for him on Sundays at a technical college. He started these aged 11. Aged 15, Heinrich left Dr. Lange’s school to be educated at home. He had decided that perhaps he would like to go to university after all. Now he received tutoring in Greek and Latin to prepare him for the exams. He excelled at languages, a gift he seems to have inherited from his father. Professor Redslob, a language specialist who gave Heinrich some tuition in Arabic, advised his father that Heinrich should become a student of oriental languages. Never before had he met anyone with greater natural talent. Heinrich also began studying the sciences and mathematics at home, again with the help of a private tutor. He had a colossal appetite for hard work. His mother said: "When he sat with his books nothing could disturb him or draw him away from them." Although he had left his normal school, he continued attending the technical college on Sunday mornings. In the evenings he worked with his hands. He learned to operate a lathe. He built models and began constructing increasingly sophisticated scientific apparatus such as a spectroscope. He used this apparatus to do his own physics and chemistry experiments. Aged 17, Heinrich returned to school, the Johanneum, for a year in order to fully prepare for the classics exams for university. Having passed the exams, he promptly changed his mind again, deciding to become an architect’s apprentice. He moved to Frankfurt, where by day he worked in an architect’s office and in the evening he read physics books in German, and Ancient Greek literature in the original Ancient Greek – naturally! Architecture quickly bored him. In spring 1876, aged 19, he moved again, to Dresden, to study engineering. After only a few months he was drafted into the army for a year’s compulsory service. Although he enjoyed the discipline of army life, he found the army boring. Rather miserably, he wrote home at one point:
“… day by day I grow more aware of how useless I remain in this world.”
HEINRICH HERTZ
1876
Meanwhile, his interest in mathematics and physics continued to grow. After completing his army service, the 20-year-old Hertz moved to Munich to begin an engineering course in October 1877. A month later, after much internal anguish, he dropped out of the course. He had decided that above all else he wanted to become a physicist. He enrolled at the University of Munich, choosing courses in advanced mathematics and mechanics, experimental physics, and experimental chemistry. After a successful year at Munich he moved to the University of Berlin because it had better physics laboratories than Munich. In Berlin, aged 21, Hertz began working in the laboratories of the great physicist Hermann von Helmholtz. Helmholtz must have recognized a rare talent in Hertz, immediately asking him to work on a problem whose solution he was particularly interested in. The problem was the subject of a fierce debate between Helmholtz and another physicist by the name of Wilhelm Weber. The University of Berlin’s Philosophy Department, with Helmholtz’s encouragement, had offered a prize to anyone who could solve the problem: Does electricity move with inertia? Alternatively, we could frame the question in the form: Does electric current have mass? Or, as framed by Hertz: Does electric current have kinetic energy? Hertz started work on the problem and quickly fell into a pleasant routine: attending a lecture each morning in either analytical dynamics or electricity & magnetism, carrying out experiments in the laboratory until 4pm, then reading, calculating, and thinking in the evening. He personally designed experiments which he thought would answer Helmholtz’s question. He began to really enjoy himself, writing home:
“I cannot tell you how much more satisfaction it gives me to gain knowledge for myself and for others directly from nature, rather than to be merely learning from others and myself alone.”
HEINRICH HERTZ
1878
In August 1879, aged 22, Hertz won the prize – a gold medal. In a series of highly sensitive experiments he demonstrated that if electric current has any mass at all, it must be incredibly small. We have to bear in mind that when Hertz carried out this work the electron – the carrier of electric current – had not even been discovered. J. J. Thomson’s discovery was made in 1897, 18 years after Hertz’s work. Other physicists began to notice just how dazzling Hertz’s work was – the young student put together experiments at the forefront of physics, personally modifying apparatus as needed. His practical skills, developed at home in the evenings, were proving to be priceless. His prize-winning work was published in the prestigious journal Annalen der Physik. Recognizing the incredible talent he had in his laboratory, Helmholtz now asked Hertz to compete for a prize offered by the Berlin Academy: verifying James Clerk Maxwell’s theory of electromagnetism. Maxwell had stated in 1864 that light was an electromagnetic wave and that other types of electromagnetic wave could also exist.