Author: Professor Aleksandar Petrovic, Ph.D.

Milutin Milankovic was educated as the civil engineer. The science today does not only pay homage to the theory of ice ages my Milankovic, but also to his practical work in civil engineering. “ in the course of the XIX century, many essays have been written about the theory of pressure on the context of balance of the structures in civil engineering. However, the general dispute on the theory on the line of pressure from the mathematical and mechanical point of view can be found only in the contributions of the Serbian scientists Milutin Milankovic, published in 1904 and 1910, essentially unknown to the historians of mechanics applied in architecture (Federico Focce). That is the case of the Milanovic theory of the bended pressures, which was highly praised by the European civil engineer, because Milanovic, on the basis of several basic hypotheses formulated the equations of mechanics behavior of concrete. He understood that the main characteristic of the concrete structures is the general balance and not the local tension. In that aspect, and in spite of time, his contribution ideally belongs to the pre-elastic tradition and anticipates his modern view of the matter. … “His theory of the line of pressure is probably the most generous discussion in the technical literature on the subject. Among the previous and the recent studies on this subject, it is difficult from the mathematical and mechanical point of view, to find even approximately so high standard of processing" (Federico Focce).

This opinion of the modern science has been anticipated also at the very beginning of the engineering career of Milanovic. On one occasion, his boss said to the owner of company where Milanovic had been working “… all those engineers are from my generation, they are all my school friends and I have kept good relationship with them, so I know how excellent they are. All of us together do not know as much as this young doctor of technology.” For only five years, for as long as he stayed in the Viennese civil engineering companies, Milanovic participated in the building of a great number of buildings. Here we would like to underline the aqueduct in Sibs as well as those projected in Simmering and Paten (Austria), then the bridges in Koran, Ban Hilda (Hungary), Isle (Austria), as well as the projects of the Belgrade sewing system, the new buildings of the Crop Factory of metal in Bergdorf… This is only a small part of what Milanovic did for only five years of his engineer service in Vienna.

Out of this large and multifaceted work, three patents were protected in Austria and one in Hungary, which refer to the application of the armed concrete in the building of ceilings. The first one was applied on July 17, 1905 with Theodore Croce with whom he worked in the company of baron Patel. At the same year, the first ceiling was made according to his system in the palace Cristal Hoff in Vienna at the Ring, “where it goes towards the Danube canal”. The commission of the professors of the Vienna Technical High School, headed by professor Brick, did the honor to Milanovic to apply his patent while building the ceiling of the new part of their school. For the young engineer, it was the affirmation he desired and his name was soon well known in the expert circles. But when using rights from the patents, Milankovic, like the majority of the inventors, had the bitter experience, because his nature did not make it possible for him to take part in the business machinations which are the essential condition for the success of the product.

Some decades later, on December 1, 1933, Milankovic got the Yugoslav patent Anti-aircraft cannon ball. In that patent, Milankovic applied the knowledge on the circular motion in order to get the anti-aircraft cannon ball. “ The effect of this cannon ball in the anti-aircraft fight is the following: the time switch B (fig. 1)of the bullet is arranged in such a way as to lead to explosion, but for a short time, before the inner filling C of the destructive grenade , and the front part of the ball is exploded, the switch by means of the firing of the incentive mass of the gun powder k is brought to effect. In the middle of explosion , the front and the back part of the bullet shall be separated from one another . The front part shall go faster, and the back part slower, due to which both parts of the bullet shall move according to the same route, but with growing distance among them and each shall rotate around its own axes. After a very short period of time, adjusted by the burning of the mass b, the flame shall reach the channel L,L and fire the gun powder filling gg. Due to that, the bullets aa of the small caliber, shall overcome the resistance of the closure ee, and be expelled from the drum E, E (picture 1 and 2). But bearing in mind that the drum rotates with the great speed around its axes, every one of the bullets, apart from the speed V in the direction of the translatory movement of the drum shall get the speed v (picture 2). Due to that, the bullets a,a shall fly away from one another and continue moving according to its own path which will close with the path of the drum and front grenade the angle with the tangens equal to v/V. That distribution of paths of the separate parts of the primary aircraft cannon ball is shown in the picture 4…”

Maybe the best conclusion on the value of the engineering creation was given by Milankovic himself. “When, as a chief of the technical department I employeed new engineers, I never asked to see their university degrees or marks. I could give better evaluation of their work based on the working experience. My theoretical knowledge would not be much valuable without being added by practical experience”.

Staring from this, he left real legacy to inventors that wish to realize the practical application from their inventions. “Capital is necessary for that, and the benefit is not obtained by the inventor but by the users of his patent, capitalists and skillful merchants. At the same time the inventor gets nothing and if his invention is lucrative, they take the skin of his back. I have seen that on uncle Andreja, and to still more dangerous degree on Nikola Tesla. Others are using his inventions, and he stayed poor. For the utilization of patent, it is necessary to have commercial spirit and to be ready for legal disputes with the villains. I had neither the capacity nor the nerves for that, so when I understood that, I decided to use my inventive capacities in the field where they would be protected from all nerve racking situations and cunning plans and that means in the field of science. What is created in science remains the undisputable property for centuries.”

Professor Aleksandar Petrovic, Ph.D. is a full time professor at the Belgrade University. He teaches the history of science, theory of knowledge, theory of culture and civilization and ethics. He is the correspondent member of the Academie internationale d histoire des sciences from paris, member of the department of Social sciences of Matica Srpska, the secretary of the Board of SANU for the work of the Milutin Milankovic, president of the Serbian Societe for the History of Science, member of the Scientiifc council of the Central Institute for Conservation, member of the Council for the History and Philosophy of Science in Belgrade. He is the editor in the scientific magazines Newsletter for the History of Science in south Eastern Europe, Natural Hellenic Research Foundation, Athens, Greece, Almagest, International Journal for the History of Scientific Ideas, Brepols Publishers, Belgium, People Say, Toronto, Canada, Annales Universitatis Paedagogicae Cracoviensis, Cracow, Poland, Modern Research Studies, University of Agartala, India, He got Tesla Award, Ford Award for the Maintenance of heritage, Special Award of the Association of Inventors of Serbia.