Schooling of Nikola Tesla in Croatia and his teacher Martin Sekulić

Tesla's autobiography entitled My Inventions was published as a series of six articles in Electrical Experimenter (popular-scientific monthly) during 1919, in the time when the journal was printed in one hundred thosand copies. Its editor in chief was Hugo Gernsback, also an inventor and considered as "The Father of Science Fiction" in the modern sense.

Tesla was very fluent in English. His sentences are brilliantly polished, with occasional usage of expressions in Latin, German and French.

Tesla's personality is marked among others by deep idealism and humanism, knowledge of literature, fluency in several world languages (German, French and English), as well as by deep knowledge and understanding of diverse aspects of Electrical Engineering.

At the age of ten I entered the Real Gymnasium [Gospić] which was a new and fairly well equipt institution. In the department of physics were various models of classical scientific apparatus, electrical and mechanical. The demonstrations and experiments performed from time to time by the instructors fascinated me and were undoubtedly a powerful incentive to invention. I was also passionately fond of mathematical studies and often won the professor's praise for rapid calculations.

Electrical Experimenter
April 1919, p. 863, left column, line 1

These Tesla's sentences should incite us to study his education in the Lower Real School in Gospić, in the period of his schooling there from 1862 till 1870: finding out the names of his teachers, the content of various school subjects, etc.

Tesla attended the Lower Real School in Gospić during three years. The lectures were taught in Croatian language for all subjects, while German was taught as a separate subject. See [Strohal, p. 89].

Zagreb - Karlovac: 53 km Gospić - Smiljan: 5 km

Karlovac - Gospić: 152 km

Schooling of Nikola Tesla in Rakovac 1870-1873

At that time, Karlovac was an advanced city, with agile cultural and economic life. For example, already in 1858 it had a singing society Zora (i.e., Dawn, the oldest Croatian singing association). In 1867 it had as many as 60 singers. A more detailed information can be found in the monograph [Strohal]. In Strohal's monograph (p. 104), it is stressed that the working language of the Higher Real School in Rakovac was German, except for the separate school subject called "Croatian Language". Starting with the automn 1870, the subjects "History" and "Religion" were also taught in Croatian. Since 1874, all the school subjects had to be taught in Croatian language, but the lack of Croatian native speaking personnel made it impossible. Therefore, in the automn of 1878, it was decided that a half of the school subjects (Religion, Croatian language, History, and Geography) should be lectured in Croatian, while the rest (i.e., the so called "real school subjects") should be taught in German. It was only in 1883, when the whole of the Military frontier (Vojna krajina) was adjoined to Croatia, that all the school subjects were taught in Croatian language.

Until 1883 (i.e., until the 'unification of Military Frontier with the motherland'), the Imperial and Royal Real School in Rakovac was under the military command of Croatia's capital Zagreb. After 1883, the school was under the direct control of the Royal Land Government in Zagreb. See [Strohal, p. 104].

In the text below, on the left-hand side to the photo of the induction motor, there comes the most interesting part for us. Nikola Tesla mentions Martin Sekulić in four sentences, although he does not explicitly mention his name (similarly as in the case of his mother Georgina or Đuka elsewhere in the book).

Here is Tesla's description of Martin Sekulić, his professor of Physics at the Higher Real School in Rakovac:

I had become intensely interested in electricity under the stimulating influence of my Professor of Physics, who was an ingenious man and often demonstrated the principles by apparatus of his own invention. Among these I recall a device in the shape of a freely rotatable bulb, with tinfoil coatings, which was made to spin rapidly when connected to a static machine. It is impossible for me to convey an adequate idea of the intensity of feeling I experienced in witnessing his exhibitions of these mysterious phenomena. Every impression produced a thousand echoes in my mind. I wanted to know more of this wonderful force; I longed for experiment and investigation and resigned myself to the inevitable with aching heart.

Electrical Experimenter
April 1919, p. 865, left column, on the left of the photo

The name of Martin Sekulić has been almost entirely left out in the contemporary literature about Nikola Tesla, and there is hardly any book in which his name is at least mentioned. This represents a grave injustice to Nikola Tesla.

In 1882, the citizens of Karlovac decided to extend the building of the Higher Real School in Rakovac, mostly for the sake of economy, in order to unite the school with the then Gymnasium in the city of Karlovac. Hence, the so called Royal Great Gymnasium in Karlovac was founded, placed in the building of the former Higher Real School in Rakovac. This has been done in 1882/83. See [Strohal, pp. 104-105]. The Higher Real School in Rakovac (intended for military profession) was cancelled as an institution, because the Military Frontier was returned under the complete sovreign administrative rule of Croatia.

Martin Sekulić (1833-1905), Tesla's teacher

In the period of 1870-1873 (i.e., in the course of three school years: 1870/71, 71/72, and 72/73) Tesla was educated in the town of Rakovac from his 14th to 17th years. Rakovac is today a part of the city of Karlovac.

Martin Sekulić directed a physical laboratory in the Higher Real School in Rakovac, which was equipped with of as many as 579 instruments!
(see Statistika nastave u kraljevini Hrvatskoj i Slavoniji i hrvatsko-slavonskoj Vojnoj krajini školske godine 1871-72., Zagreb 1873.)

Among his basic school subjects in Rakovac, Tesla had Croatian Language (Kroatische Sprache) as his mother tongue.

As we can see on the photo of Martin Sekulić and his colleagues in the Rakovac Higher Real School (kept in the Croatian School Museum in Zagreb), the professors wore nice uniforms. The students also wore the uniforms, but we do not knoow how they looked like.

The Higher Real School served to educate students for military profession in Croatian-Slavonian Military Frontier (Hrvatsko-slavonska vojna krajina). The occupied parts of Croatian territories (roughly, western part of today's Bosnia and Herzegovina between rivers Una and Vrbas) became known as Turkish Croatia. Indeed, on various maps from that time (18th-19th centuries), we encounter the names od TĂźrkisch Kroatien (in German), Croatie Turc (in French), Croazia Turca (in Italian).

As Nikola Tesla, Martin Sekulić (1833-1905) was also born in the Croatian region of Lika, in the town of Lovinac. Martin Sekulić has noble roots: he is descendent of the city of Senj nobility. On his grave in the Mirogoj Cemetery we can read MARTIN SEKULLIĆ, carved with the double L.

The Military Frontier (Vojna granica) is oficially called Croatian Military Frontier or Croatian-Slavonian Military Frontier (Hrvatsko-slavonska vojna krajina).

Some of the disciplinary regulations during Tesla's education in Croatia were:

11. Kada učitelj stupi u školsku sobu, podignuti će se svi učenici sa svojih mjesta... (When a teacher enters a class, all students will raise)
12. Nauk se molitvom i započima i dovršuje (Each lesson starts and ends with prayer)
22. Poslie svake dvie ure poldašnjega nauka daje se učenikom odmor deset časaka (minuta)... (After every two hours of daily teaching, students are given 10 minutes of rest)

In 1873, Tesla completed his secondary schooling with matriculating in front of the committee consisting of eleven (sic!) professors. Due to the existence of such a serious exam, he did not have to enter the admission exams in any of the high technical schools in Austro-Hungarian Empire. Thus, he enrolled directly at the prestigious High Technical School in Graz, Austria. Most probably there Tesla met Antun Lučić - Anthnoy F. Lucas, the future Father of Petroleum Engineering (Tesla's compatriat, born in 1855 in the city Splitu, one year before Nikola Tesla).

It is little known that the last Turkish Osmanly (Ottoman) attack on the city of Karlovac, attempting its occupation, took place in 1878, i.e., only five years after Tesla's completion of his schooling in Rakovac. (this information is given by the courtesy of Antun Milinković, professor at the Gymnasium of Karlovac, actually working in the same building in which Nikola Tesla attended the then Higher Real School.

Martin Sekulić - corresponding member of JAZU (today HAZU - Croatian Academy) in Zagreb

In 1873, at the age of 40, Martin Sekulić became a corresponding member of the Academy in Zagreb, at the Department of Mathematics and Natural Sciences. In that year, Tesla was completing his schooling in Rakovac, where Martin Sekulić was his professor.

Martin Sekulić has 13 published papers (three of them in prestigious Annalen der Physik, one in Wiener Any. Jahrg, and nine papers in Rad JAZU, a journal of the Academy which exists also today); see [Vuković and Valent].

• Beziehungen zwischen der elektromotorischen Kraft und der chemischen WärmetĂśnung
• Ultraviolette Strahlen sind unmittelbar sichtbar; In Chemisches Central-Blatt, Band 43, 1872
• Eine merkwĂźrdige Interferenzerscheinung; Pogg. Ann. (tj. Poggendorffs Annalen), CXLIX, 126. 1873
• Fizika atoma i molekula (Physics of the atoms and molecules), Rad JAZU,  Knj. 26(1874) str. 109-152.
• Ueber die an bestäubten und unreinen Spiegeln sichtbare Interferenzerscheinung; In: Annalen der Physik; Volume 230, Issue 2, S. 308–316, 1875, doi:10.1002/andp.18752300212.
• Uzrok munjotorskoj sili (The source of electrical force), Rad JAZU, br. 41 (1877), br. 50 (1879), br. 58 (1881)
• O ledenoj dobi sjeverne polutke naše zemlje (On the Ice Age in the northern hemisphere), JAZU 64 (1882)

An article by Martin Sekulić published in prestigious German scientific journal Annalen der Physik in 1875.
Here we can see a part of the first page (p. 308); the whole first page: [JPG].
Instead of Rakovac, in the title there a small mistake: Rokovac.
Below his name, it is stressed that he is a professor in Rakovac in Croatia,
and that the paper represents a translation from Croatian language.
The entire Sekulić's work is available (upon paying) at doi:10.1002/andp.18752300212.

Lissajous curves that Martin Sekulić drew and described in his paper
Fizika atoma i molekula (The physics of the atoms and molecules), Rad JAZU Knj. 26(1874) p. 109-152.
Sekulić constructed a special apparatus for drawing Lissajous curves. See [Muljević, str. 334].

Tesla became a corresponding member of the Academy (JAZU, now HAZU) in Zagreb in 1896, also at the age of 40 as Sekulić. The Academy (JAZU) in Zagreb was founded in 1866. Martin Sekulić became its member seven years after its founding, while Nikola Tesla was elected thirty years after its founding.

Sekulić enthused Tesla for Bošković, by popularizing Bošković's idea that the whole Physics can be founded on the unique type of force.

The prestigious journal Annalen der Physik was founded already in 1790 (in the time of the beginnings of Sekulić's scientific work, the complete name of the journal was Annalen der Physik und Chemie). Martin Sekulić published his papers in this journal in 1872, 1873, and in 1875, in German language. This shows that young Nikola Tesla listened to the lectures of Martin Sekulić at the time of his greatest scientific activities.

Since 1895, German Nobel Prize winner Max Planck served as an associated editor of Annalen der Physik, while from 1907 till 1943, he was its editor in chief.

We mention in passing that in 1942, at the age of 84, Max Plack delivered an invited lecture at the University of Zagreb. He was welcomed by the then rector Stjepan Ivšić, distinguished Croatian linguist. The lecture was conducted in the stuffed lecture hall of the then Technical Faculty (of the University of Zagreb) in Kačićeva street 26, entitled "The meaning and bounds of exact natural sciences." No photo of Planck's sojourn in Zagreb has been preserved. Even the Hotel Esplanade in Zagreb, where Planck stayed, has no preserved information about the sojourn of distinguished scientist (all the documents were destroyed after 1945, during the communist time in ex-Yugoslavia).

During his lecture in Zagreb, Planck spoke among others about the danger of the atomic bomb (which was for the first time unveiled for the broad public). See [Leo Randić].

Other Tesla's professors in Rakovac

Nikola Tesla matriculated on July 24th, 1873. In his matriculation form (written in German; see the photo below) Tesla is mentioned as seventh in order, and his birth date is mistakenly written as Novemeber 2nd, 1856 (should be 9/10 July)

• ISPITANIKOVO IME (name of the examenee): Nikola Tesla
• VJERA (faith): grčke nesjedinjene (Greek nonunited)
• RODNO MJESTO (birthplace): Smiljan u Vojnoj krajini (Smiljan in Military Frontier)
• DOMOVINA (homeland): Hrvatska (Croatia)
• STAROST (age): rodj. (born on) 2. novembra 1856. god. (should be July 9/10, 1856)
• ZANIMANJE RODITELJA (occupation of parents): Sin grčkonesjedinjenog protojereja Milutina Tesle (son of Greek nonunited archpriest Milutin Tesla)
• STUDIJ GIMNAZIJE (study at gymnasium school): Učio malu realku u Gospiću, a veliku realku svršio u Karlovcu (attended Lower Real School in Gospić, and Higher Real School in Karlovac)

Statistics of teaching from 1871. (i.e., from the year when young Nikola Tesla was a student at the Rakovac Higher Real School, at the age of 15) inform us that

the Physics cabinet in the Rakovac Higher Real School possesses as many as 579 (five hundred and seventy nine) instruments! This cabinet, as we have already mentioned, was directed by professor Martin Sekulić. (The source of this important information is: Statistika nastave u kraljevini Hrvatskoj i Slavoniji i hrvatsko-slavonskoj Vojnoj krajini školske godine 1871-72., Zagreb 1873. / Statistics of Teaching in the Kingdom of Croatia and Slavonia and in Croatian-Slavonian Military Frontier in the School Year 1871-1872)

All this shows us that young Nikola Tesla had excellent professors, and that his school in Rakovac was enviably equipped with teaching tools, especially in the field of Physics (including Electrical Engineering).

Nikola Tesla and Croatian language

In 1868, a decision was taken that the Croatian language should be equal to German in all gymnasiums and real schools on the territory of Croatian-Slavonian Military Frontier. It was not possible to carry out this decision in the Lower Real School in Gospić (where Tesla completed his first three years of education), "because only two teachers know Croatian langague" (namely, in the aforementioned school the majority of teachers were foreigners, who were lecturing in German). The Gospić Lower Real School added the fourth grade only in 1872. See [Petešić, p. 28]. For the same reason, it was only in 1874 that the Higher Real School in Rakovac passed to the teaching in Croatian language. Until then, there was a special subject called Kroatische Sprache (Croatian Language), which was listened to by young Nikola Tesla.

In 1871 (when Tesla was at the age of 15), the Higher Real School in Rakovac added the seventh grade, by interpolating an additional grade between three lower and three higher grades. For this reason, Nikola Tesla skipped the fifth grade, and jumped from the fourth grade immediately to the sixth grade.

All the school subjects apearing in the Yearbook of the Imperial and Royal Higher Real School in Rakovac (Godišnje izvješće Carske i kraljevske velike realke u Rakovcu) for the period of 1872-1874, are described not only in German, but also in Croatian language.

Let us see the content of the subject Croatian Language in Tesla's school in Rakovac (three hours weekly):

Let us see the school subject called prirodoslovje (i.e., Physics; four school hours weekly):

Let us also see mathematika, i.e., Mathematics (five school hours weekly):

In time when Nikola Tesla was a secondary school student at the Higher Real School in Rakovac (at the age of 14-17), there was an elective school subject called pjevanje (gesang), i.e. Singing:

The above information about singing can be found in the Yearbook (Godišnje izvješće) published in Zagreb (Agram) in 1871/1872.

Tesla's diplomas and documents from Rakovac

Tesla's mother tongue during his schooling was Croatian: