Hermann Ludmig Ferdinand Helmholtz - biography. Great doctors: Helmholtz

Hermann Helmholtz (Herman Ludwig Ferdinand Helmholtz) (1821-1894) - German scientist, foreign corresponding member of the St. Petersburg Academy of Sciences (1868). Author of fundamental works on physics, biophysics, physiology, psychology. For the first time (in 1847) he mathematically substantiated the law of conservation of energy, showing its universal nature. He developed a thermodynamic theory of chemical processes and introduced the concepts of free and bound energies.

Whoever once comes into contact with a first-class person, his spiritual scale is changed forever - he has experienced the most interesting thing that life can give.

Hermann Helmholtz laid the foundations for the theories of vortex fluid motion and anomalous dispersion. Author of fundamental works on the physiology of hearing and vision. He discovered and measured heat generation in muscles, studied the process of muscle contraction, and measured the speed of propagation of a nerve impulse. Supporter of physiological idealism.

Hermann Helmholtz is one of the greatest scientists of the 19th century. Physics, physiology, anatomy, psychology, mathematics... In each of these sciences, he made brilliant discoveries that brought him worldwide fame.

Hermann Ludwig Ferdinand Helmholtz was born on August 31, 1821 in the family of a Potsdam gymnasium teacher. At the request of his father, in 1838 Herman entered the Friedrich-Wilhelm Military Medical Institute to study medicine. Under the influence of the famous physiologist Johann Muller, Helmholtz devoted himself to the study of physiology and, after taking a course at the institute, defended his doctoral dissertation in 1842 on the structure of the nervous system. In this work, the twenty-two-year-old doctor first proved the existence of integral structural elements of nervous tissue, which were later called neurons.

In the same year, Hermann was appointed as a resident at a hospital in Berlin. In 1843, Helmholtz began his career as a Potsdam military doctor. He lived in a barracks and got up at five o'clock in the morning at the signal of a cavalry trumpet. But the squadron surgeon of the hussar regiment also found time to study science. In 1845, he said goodbye to military service and went to Berlin to prepare for the state exams to become a doctor. Helmholtz studies diligently in the home physics laboratory of Gustav Magnus.

Happy glimpses of thought often invade your head so quietly that you don’t immediately notice their meaning... The thought comes over you suddenly. It is never born in a tired brain or at a desk. It often appears early in the morning upon awakening, and it comes especially readily during the hours of a leisurely climb through wooded mountains on a sunny day.

Helmholtz Hermann Ludwig Ferdinand

Alexander Grigorievich Stoletov, who sensitively sensed the turning point in the scientific development of Germany in the forties, wrote: “Magnus’s home laboratory - the first example of a physical laboratory - is becoming a breeding ground for experimental physicists.” Subsequently, a graduate of this laboratory, Hermann Helmholtz, becomes Magnus's successor and moves the laboratory to the building of the University of Berlin, where it turns into a world scientific center.

Another of Helmholtz's teachers in Berlin was Johann Müller. Much later, on November 2, 1871, at a celebration of Helmholtz on the occasion of his seventieth birthday, he gave a speech in which he described his scientific path. He indicated that, under the influence of Johann Muller, he became interested in the question of the mysterious being of the life force. Reflecting on this problem, Helmholtz, in his last year as a student, came to the conclusion that the theory of vital force “attributes to every living body the properties of the so-called perpetuum mobile.” Helmholtz was familiar with the problem of perpetual motion from his school years, and during his student years “in his free moments... he looked for and looked through the works of Daniel Bernoulli, Jean Leron d’Alembert and other mathematicians of the last century.” “Thus,” said Helmholtz, “I came across the question: “What relation should exist between the various forces of nature, if we accept that perpetuum mobile is generally impossible?” - and further: “Are all these relationships actually fulfilled?”

In Müller's journal, Hermann Helmholtz published in 1845 the work “On the expenditure of matter during the action of muscles.” Also in 1845, young scientists grouped around Magnus and Müller formed the Berlin Physical Society. Helmholtz also joined it. Since 1845, the society, which later turned into the German Physical Society, began to publish the first abstract journal “Uspekhi Physics”.

The scientific development of Hermann Helmholtz thus took place in a favorable environment of increased interest in natural science in Berlin. Already in the first volume of Uspekhi physics, 1845, published in Berlin in 1847, a review was published by Helmholtz on the theory of physiological thermal phenomena. On July 23, 1847, he made a report “On the Conservation of Force” at a meeting of the Berlin Physical Society. It was published as a separate brochure that same year.

The authorities at that time “were inclined to reject the justice of the law; amid the zealous struggle that they waged against Hegel’s natural philosophy, my work was considered fantastic intellectualism...” However, Helmholtz was not alone; he was supported by young scientists, and, above all, by the future famous physiologist Dubois-Reymond and the young Berlin Physical Society.

As for his attitude to the work of his predecessors Mayer and Joule, Helmholtz repeatedly recognized the priority of Mayer and Joule, emphasizing, however, that he was not familiar with Mayer’s work, and did not know enough about Joule’s work.

Unlike his predecessors, he connects the law with the principle of the impossibility of perpetual motion. G. Helmholtz considers matter as passive and motionless. In order to describe the changes taking place in the world, it must be endowed with forces of both attractive and repulsive. “The phenomena of nature,” says Helmholtz, “must be reduced to the movements of matter with unchanging driving forces, which depend only on spatial relationships.”

Thus, the world, according to Helmholtz, is a collection of material points interacting with each other with central forces. These forces are conservative, and Helmholtz puts the principle of conservation of living force at the head of his research. Hermann Helmholtz replaces Mayer’s principle “out of nothing nothing comes” with a more specific position that “it is impossible, given the existence of any arbitrary combination of bodies, to continuously obtain a driving force from nothing.”

The principle of conservation of living force in its formulation states: “If any number of moving material points moves only under the influence of such forces that depend on the interaction of the points on each other or that are directed towards fixed centers, then the sum of the living forces of all points taken together will remain the same same at all moments of time at which all points obtain the same relative positions in relation to each other and in relation to existing fixed centers, whatever their trajectories and velocities may be in the intervals between the corresponding moments.”

Having formulated this principle, Hermann Helmholtz considers its application in various special cases. Considering electrical phenomena, Helmholtz finds an expression for the energy of point charges and shows the physical meaning of a function called potential by Gauss. He further calculates the energy of a system of charged conductors and shows that when Leyden jars are discharged, heat is released that is equivalent to the stored electrical energy. He showed at the same time that the discharge is an oscillatory process and electrical oscillations “become smaller and smaller, until finally the living force is destroyed by the sum of the resistances.”

Helmholtz then considers galvanism. Hermann Helmholtz analyzes energy processes in galvanic sources, in thermoelectric phenomena, laying the foundation for the future thermodynamic theory of these phenomena. Considering magnetism and electromagnetism, Helmholtz, in particular, gives his famous conclusion of the expression of the electromotive force of induction, based on Neumann's research and relying on Lenz's law.

In his work, Helmholtz, unlike Mayer, pays the main attention to physics and speaks only very briefly and concisely about biological phenomena. Nevertheless, it was this essay that opened the way for Helmholtz to the Department of Physiology and General Pathology of the Medical Faculty of the University of Königsberg, where in 1849 he received the position of extraordinary professor.

Hermann Helmholtz held this position until 1855, when he became a professor of anatomy and physiology in Bonn. In 1858, Helmholtz became a professor of physiology in Heidelberg, where he worked extensively and successfully on the physiology of vision. These studies have significantly enriched the field of knowledge and practical medicine. The result of these studies was the famous “Physiological Optics” by Helmholtz, the first issue of which was published in 1856, the second in 1860, and the third in 1867.

The eye is one of the most remarkable organs of our body. They knew about his work before and compared it to the work of a photographic camera. But to fully clarify even just the physical side of vision, a rough comparison with a camera is not enough. It is necessary to solve a number of complex problems from the field of not only physics, but also physiology and even psychology. They had to be resolved with a living eye, and Hermann Helmholtz managed to do this. He built a special device (ophthalmometer), amazing in its simplicity, which made it possible to measure the curvature of the cornea on the posterior and anterior surfaces of the lens. This is how the refraction of rays in the eye was studied.

We see objects painted in one color or another, our vision is colored. What is it based on? A study of the eye has shown that the retina has three main light-sensing elements: one of them is most irritated by red rays, the other by green rays, and the third by blue rays. Any color causes a stronger irritation of one of the elements and a weaker irritation of the others. Combinations of irritations create the entire play of colors that we see around us.

To examine the bottom of the living eye, Hermann Helmholtz made a special device: an eye mirror (ophthalmoscope). This device has long become mandatory equipment for every eye doctor. Helmholtz did a lot to study the eye and vision: he created physiological optics - the science of the eye and vision.

Here, in Heidelberg, Helmholtz conducted his classical studies on the speed of spread of nervous excitation. Frogs for dissection have visited the scientist’s laboratory table many times. He studied the speed of excitation propagation along the nerve. The nerve received irritation from the current, the caused excitation reached the muscle, and it contracted. Knowing the distances between these two points and the time difference, you can calculate the speed of excitation propagation along the nerve. It turned out to be very small, only from 30 to 100 m/sec.

It seems like a very simple experience. It looks simple now that Hermann Helmholtz developed it. And before him, it was argued that this speed cannot be measured: it is a manifestation of a mysterious “vital force” that cannot be measured.

Helmholtz did no less to study hearing and the ear (physiological acoustics). In 1863, his book “The Doctrine of Sound Sensations as the Physiological Basis of Acoustics” was published.

And here, before Helmholtz’s research, much related to hearing was studied very poorly. They knew how sound originated and propagated, but very little was known about the effects that sounds have on objects capable of vibrating. Hermann Helmholtz was the first to tackle this complex phenomenon. Having created the theory of resonance, he then created on its basis the doctrine of auditory sensations, our voice, and musical instruments. While studying the phenomena of oscillations, Helmholtz developed a number of questions that are of great importance for the theory of music, and gave an analysis of the causes of musical harmony.

The example of Helmholtz shows the great importance of the breadth of a scientist’s horizons, the richness and diversity of his knowledge and interests. There, in Heidelberg, his classic works on hydrodynamics and the foundations of geometry were published.

Since March 1871, Helmholtz became a professor at the University of Berlin. He created a physics institute where physicists from all over the world came to work.

After moving to Berlin, Hermann Helmholtz devoted himself exclusively to physics, and studied its most complex areas: electrodynamics, in which, based on the ideas of Faraday, he developed his own theory, then hydrodynamics and the phenomena of electrolysis in connection with thermochemistry. Particularly remarkable are his works on hydrodynamics, begun back in 1858, in which Helmholtz gives the theory of vortex motion and fluid flow and in which he manages to solve several very difficult mathematical problems. In 1882, Helmholtz formulated the theory of free energy, which solves the question of what part of the total molecular energy of a certain system can be converted into work. This theory has the same meaning in thermochemistry as Carnot's principle in thermodynamics.

In 1883, Emperor Wilhelm granted Wilhelm Helmholtz the title of nobility. In 1884, Helmholtz published the theory of anomalous dispersion, and a little later several important works on theoretical mechanics. Works on meteorology date back to the same time.

In 1888, Helmholtz was appointed director of the newly established government physical and technical institute in Charlottenburg - the Center for German Metrology, in the organization of which he took an active part. At the same time, the scientist continues to lecture on theoretical physics at the university.

Helmholtz had many students; Thousands of students listened to his lectures. Many young scientists came to work in his laboratory and learn the art of experimentation. Many Russian scientists can be considered his students - physiologists E. Adamyuk, N. Bakst, F. Zavarykin, Ivan Sechenov, physicists Pyotr Lebedev, P. Zidov, R. Colley, A. Sokolov, N. Shidder.

Unfortunately, not only joyful events awaited Helmholtz in his old age. His son Robert, a promising young physicist, died untimely in 1889, leaving his work on the radiation of burning gases.

The scientist's most recent works, written in 1891-1892, relate to theoretical mechanics.

Hermann Ludwig Ferdinand Helmholtz - quotes

An unheard of thing happened: a physician and professor of physiology occupied the main physics department in Germany.

Your rich practical experience with intelligent and interesting problems will point mathematicians in a new direction and give them new impetus... One-sided and introspective mathematical reasoning leads to areas from which no valuable fruit can be expected.

The slightest doses of alcoholic beverages destroy the possibility of happy thoughts arising, killing them in their infancy.

Although science is a factor that awakens and shapes the most refined faculties of human consciousness, yet one who studies and researches only to know will not find the true meaning of his own existence on Earth. Only active activity makes human existence worthy.

Hermann-Ludwig-Ferdinand von Helmholtz was considered a national treasure in Germany. He managed to become the first doctor among scientists and the first scientist among doctors. Interesting fact. Although Helmholtz was as profound, as broad in his scope of knowledge, and as brilliant in his research as Leibniz, he had a poor memory, was a very mediocre student, and graduated from high school with a poor performance. During his studies at the gymnasium, no one could even think that he would do so much useful in science! However, Herman became an outstanding physiologist. And moreover, the name of the doctor, mathematician, psychologist, professor of physiology and physics Helmholtz, inventor of the eye mirror, in the 19th century is inextricably linked with the radical reconstruction of physiological concepts. A brilliant expert in higher mathematics and theoretical physics, he put these sciences at the service of physiology and achieved outstanding results.

Hermann's father August-Ferdinand-Julius Helmholtz (1792-1859) received higher education at the University of Berlin, where he first studied at the Faculty of Theology and studied philosophy. In 1813, captivated by the idea of ​​national revival of Germany, he volunteered to join the army and, despite poor health, spent two years on campaigns. After the conclusion of peace, he again entered the university, this time at the Faculty of Philology. He passed a special examination in 1820 and received a position as head teacher at the Potsdam gymnasium. In the first year of his teaching he married Caroline Penn, the daughter of an artillery officer, descended through the male branch from a famous American, and through the female branch from the Sauvage family, which moved to Germany at the beginning of the 19th century and belonged to the Huguenots; so that, like the von Humboldt brothers, Hermann Helmholtz was partly French.

At the gymnasium, August-Ferdinand taught German, philosophy, interpreted Plato, read Homer, Virgil, Ovid, and even taught mathematics and physics at one time. His favorite subject, however, was Greek literature and culture. As an outstanding teacher, he was appointed sub-rector in 1827, and a year later received the title of professor. He remained a teacher at the gymnasium where his son Herman would soon go to study until 1857, then retired, receiving a pension.

Hermann was born on August 31, 1821 in the German city of Potsdam. Besides him, two girls and a boy later appeared in the family. As a child, Herman grew up as a frail child and was often ill for a long time. Each illness made his parents tremble, fearing for their first-born. Early on, a certain flaw in his mental makeup was revealed: a weak memory for things that do not have an internal connection. He had difficulty distinguishing between the right and left sides. Later, when he studied languages ​​at school, he found it more difficult than others to remember irregular grammatical forms, especially figures of speech. He barely mastered history; it was a pain to learn passages in prose by heart. This deficiency only intensified over the years and became the scourge of his old age. When Cicero or Virgil were being read in class, he calculated the path of rays in telescopes under the table and even then found some optical theorems that were not mentioned in textbooks.

On September 12, 1838, Herman graduated from high school, and the question arose about choosing a career. Of the sciences, he was most attracted to natural science. However, the lack of the necessary funds to devote himself to pure science forced Herman’s father to advise his son not to go to the Faculty of Science, and Herman decided to devote himself to the study of medicine as a field that could help him settle down in the future so as not to interrupt his studies in physics and mathematics . Added to this was another favorable circumstance, which decided the whole matter; the only relative involved in science in the Helmholtz family was Murenin, who occupied a prominent position. He undertook to work for Herman to be admitted at the state expense to the Friedrich-Wilhelm Military Medical-Surgical Institute in Berlin, which trained military doctors.

A seventeen-year-old student studies physics, chemistry and anatomy in the first semester. In addition to these main subjects, in the first year he studied logic, history, Latin and French. Herman devoted his free time during vacations and holidays to reading Homer, Byron, Biot and Kant. Herman was lucky not only with his fellow students (a whole galaxy of future luminaries of physiology studied with him, who formed the flower of German science: Karl Ludwig, Dubois-Reymond, Brücke, Virchow, Schwann), but also with his physiology teacher Johannes Müller, a luminary of German physiological science. In the second semester, under the influence of his famous teacher, Herman became interested in physiology and histology. Müller's students were united by the same desire to connect physics with physiology and find a more solid foundation for their substantiation. Herman was significantly superior to his friends in his knowledge of mathematics, which gave him the opportunity to accurately “formulate problems and give the correct direction for solving them.”

Hermann's work in Müller's laboratory, which began brilliantly in his student years and captivated him, was interrupted in the fall of 1842 by practical work as a surgeon at the Charite military hospital in Berlin, which lasted a whole year and took him daily from 7 a.m. to 8 p.m. Nevertheless, on November 2, 1842, Herman defended his doctoral dissertation in Latin, “On the structure of the nervous system of invertebrates.” The topic “Structure of the nervous system” was suggested to him by Müller himself. In this dissertation, he proved for the first time that the known elements of nervous tissue, nerve cells and fibers, are connected to each other and form parts of an inextricable whole, which was later called a neuron.

The story of how Herman acquired the microscope with which he completed his dissertation work is extremely touching. Having fallen ill with typhus, as a student at the Friedrich-Wilhelm Institute, he was admitted free of charge to the Charite hospital, and thanks to this, he accumulated a small amount from the scholarship, which gave him the opportunity to purchase a microscope, albeit an inferior one.

After graduating from the institute, Helmholtz was sent to the Charité hospital as a resident, where Virchow also worked. At the same time, he works in the home laboratory of Gustav Magnus (1802-1870), the author of publications on mechanics, hydrodynamics, heat, etc. Helmholtz had to serve a seven-year fellowship as a military doctor. He managed to get a job in Potsdam, near Berlin: in October 1843 he served as a squadron surgeon in the Royal Life Guards Hussars. Helmholtz lives in a barracks, gets up like everyone else at five o'clock in the morning at the signal of a cavalry trumpet. Despite all the inconveniences of barracks life, he managed to set up a small physical and physiological laboratory and in 1845 carry out his experiments on the consumption of substances during muscular work, for which Dubois-Reymond gave him portable scales.

In the same year, physicists and chemists who worked in Magnus’s laboratory formed a physical society, which accepted the young Helmholtz. In July of the same year, Helmholtz gave an epoch-making report to the Physics Society, “On the Conservation of Force.” He tried to publish this brilliant work in a scientific journal, but it was not appreciated, so he published it in 1847 as a separate book. So, Helmholtz mathematically substantiated the law of conservation of energy proclaimed by Lomonosov back in the 18th century, showing its universal nature, and applied this law in physiology. With this work he united the physical, chemical and biological sciences, for which the principle of conservation of energy gave a solid foundation and laid the foundation for Helmholtz's worldwide fame. The first person to correctly understand and formulate this law back in 1842 was the German physician Julius Robert Mayer from Heilbronn.

On June 1, 1847, Helmholtz was transferred to the royal Gardes-du-Corps regiment, also located in Potsdam. Helmholtz met the Felton family, whose head was a military doctor. The young Olga von Felton, with whom Helmholtz often played the piano, read poetry and took part in performances, made an indelible impression on him, and on March 11, 1847, he was engaged to her. On September 30, 1848, after serving for 6 years as a military doctor, Helmholtz was promoted to senior physician. Alexander Humboldt helped Helmholtz to be released from the remaining three years of compulsory service and contributed to his appointment to Brücke's place at the Academy of Arts and the Anatomical and Zoological Museum. The Academy and Müller were very pleased with this. But as soon as Helmholtz got used to the new conditions, the next year a new assignment awaited him.

Professor Brücke was transferred to the Department of Physiology at the University of Königsberg, and he needed a deputy. It could have been either the more experienced Dubois-Reymond or Helmholtz. But since Dubois-Reymond’s father could still support him while he was engaged in scientific work, the choice fell on his friend Helmholtz. On the recommendation of Müller, Helmholtz was invited in 1849 to become a professor of physiology at the University of Königsberg. In Königsberg, in the process of his research, he designed a number of original measuring instruments. The eye mirror (ophthalmoscope) he designed, which made it possible to observe the fundus of the eye, and the so-called Helmholtz pendulum, which made it possible to expose tissue to rapidly successive irritations with a precise dosage of time, became widespread in various fields of physiological research and medicine. And nowadays, the ophthalmoscope plays a huge role in diagnosing not only eye diseases, but also nervous diseases such as brain tumors, tabes spinal cord, etc.

The Königsberg period of Helmholtz's scientific activity was the most productive. There he developed the physiological theory of hearing, according to which the phenomenon of resonance underlies the ability of animals and humans to distinguish one sound tone from another. A sound of a certain pitch does not set into oscillatory motion the entire main sound membrane, but only one group of its fibers resonating at a given sound frequency. Based on the physical laws of resonance, Helmholtz created the doctrine of the auditory function of the organ of Corti, located in the inner ear of a person.

Helmholtz's works in the field of physiology are devoted to the study of the nervous and muscular systems. He discovered and measured heat generation in muscle using the thermoelectric method (1845-1847) and, using the graphical technique he developed, studied in detail the process of muscle contraction (1850-1854) in experiments on a frog; galvanometric measurement of short time intervals (based on the ballistic principle). When Helmholtz set himself this goal, his teacher, Müller, doubted the possibility of measuring the speed of passage of excitation along the nerve, the almost immeasurably small amount of time when a person felt pain from a burn. During this insignificant period of time, excitation must travel a certain path along the nerve conductors. How to measure the speed of movement of excitations along the nerves? And is it even possible? Being the most skillful of experimenters, Helmholtz took up the solution to this problem, proposing a solution ingeniously simple.

He supplied an electric current to the frog's nerve near any of its muscles. The current excited the nerve, and the muscle responded to this stimulation by contracting. Then he irritated the same nerve with an electric current, not at the muscle itself, but at some distance from it. The muscle contracted again, but somewhat later than the first time. This difference in time, divided by the length of the nerve between the two points where the electricity was applied, indicated the speed at which the stimulus traveled along the nerve. In the frog on which Helmholtz conducted this experiment, the speed of excitation propagation along the nerves turned out to be equal to 27 meters per second. How different this relatively small speed was from the fantastic figure that scientists called! It was assumed that the speed of excitation along the nerves is equal to the speed of light - 300 thousand kilometers per second!

In 1867-1870, together with the Russian scientist N. Bakst, he measured the speed of propagation of excitation in human nerves. A number of the scientist’s studies relate to the physiology of the central nervous system. He first identified the latent period of reflexes in 1854, made the first experimental attempt to determine the rhythm of impulses sent by the brain to the muscle (1864-1868), and quantitatively determined the latent period of the volitional muscle reaction to irritation of the sense organs.

Helmholtz's teaching on “unconscious inference” as an image-building operation in which muscle movement is involved filled this category with new content. The role of muscle movement in the generation of sensory products is revealed in the teachings of I.M. Sechenov, from whom threads stretch to modern views on the mechanism of processing sensory information.

Major works that brought Helmholtz great fame and attracted the attention of the Paris Academy of Sciences prompted the Prussian Ministry of Education to approve Helmholtz as an ordinary professor in 1851, which significantly improved his financial situation. In August 1853, Helmholtz, leaving his wife and two children with his relatives, took his first trip to England, where he met Faraday.

In the field of physiology of vision, he developed methods for determining the curvature of the optical surfaces of the eye, and in 1853 he gave the theory of accommodation. He showed that visual assessment of the size and distance of objects is based on peculiar muscle sensations that arise when the muscles of the eye move. Helmholtz's idea about the role of muscle sense in the formation of perceptions was deeply developed in the psychophysiological works of I.M. Sechenov.

In developing questions of the physiology of vision, Helmholtz was constantly helped by his wife, who was his friend and assistant; she copied his manuscripts, and he was the first to give his lectures to her. In 1854, a quiet, happy, secluded life was overshadowed by the death of his beloved mother. At the same time, his wife's tuberculosis began to threaten her health. Helmholtz began to take measures to move to another city, where the climate was milder, and such an opportunity presented itself to him when the Department of Physiology and Anatomy in Bonn became vacant. In 1855 he was appointed to the department of anatomy and physiology at the University of Bonn, where he worked until 1858.

At the ophthalmological congress in Paris, where in 1867 he read a report on the sense of relief, the words were heard at a gala dinner: “Ophthalmology was in darkness - God said that Helmholtz was born - and the light shone.” In 1859-1866, Helmholtz studied the psychology and physiology of sensory processes (visual, auditory) and color perception. He fully developed the doctrine of color vision, based on the assumption that the retina has three main color-sensing elements. Developing the idea that there are three elements in the retina that are sensitive to red, green and blue, he developed a theory of the emergence of color visual sensations. Red, green and violet, according to Helmholtz, are the primary colors, from the optical mixing of which the entire infinitely rich palette of colors perceived by the human eye arises. Helmholtz's theory has stood the test of time and today satisfactorily explains the physiology of color visual sensations. It should be noted that work on the perception of complex colors was first developed by the brilliant physician and physicist Thomas Jung. Helmholtz left to humanity his remarkable research on other problems of the physiology of vision.

In 1857, the Baden government invited Helmholtz to move to the department of physiology at the famous Heidelberg University, where two of his close friends, Bunsen and Kirchhoff, were already working as professors. Little Heidelberg, one of the cities of the Duchy of Baden. On the hill are the ruins of an ancient castle. Curly oak groves look into the waters of the Neckar. The Heidelbergers pompously called the modest two-story building that housed Helmholtz's laboratory the Nature Palace. In this laboratory, Ivan Mikhailovich Sechenov studied with Helmholtz. How great the impression the teacher made on him can be judged by his following words:

What can I say about this out-of-the-ordinary person? Due to the insignificance of my education, I could not get closer to him, so I saw him, so to speak, only from afar, never remaining calm in his presence... His... figure with thoughtful eyes emanated a kind of world, as if not from this world. Strange as it may seem, I’m telling the absolute truth: he made an impression on me similar to what I experienced when looking for the first time at the Sistine Madonna in Dresden, especially since his eyes were really similar in expression to the eyes of this Madonna. Probably, he made the same impression upon close acquaintance... In Germany, he was considered a national treasure and were very dissatisfied with the description of one Englishman that in appearance Helmholtz looked more like an Italian than a German.

The first years after moving to Heidelberg were associated with difficult family experiences for Helmholtz. On June 6, 1859, his father died. This loss was very difficult, because... Throughout his life, he developed not only close family relations with his father, but also friendly relations, as evidenced by correspondence in which purely family and personal issues are intertwined with complex philosophical problems about the systems of Fichte, Hegel, and Schelling. The blissful landscape of Heidelberg was disrupted by the exacerbation of his wife’s serious illness. On December 28, 1859, Olga Helmholtz died. Due to his severe nervous state and fatigue, Helmholtz experienced frequent fainting spells, which had happened before. Two small children remained in his arms. A year later, he proposed to Anna Mol, the niece of a professor of Persian at the Collège de France in Paris. Anna spent most of her life in Paris and London and was a highly educated girl. After Helmholtz returned from England, on May 16, 1861, the wedding took place with Anna von Mohl. On November 22, 1862, Helmholtz was elected vice-rector of the University of Heidelberg. In 1864, Helmholtz visited England for the second time. In London, he visited Tyndall and Faraday, and gave a lecture at the Royal Society on the normal movements of the human eye in connection with binocular vision.

Helmholtz's work took him far beyond the boundaries of physiology, so it is not surprising that when in April 1870, after the death of Gustav Magnus, the chair of physics at the University of Berlin became vacant, Dubois-Reymond, the rector of the University of Berlin, received from the Minister of Education von Müller an order to invite Kirchhoff or Helmholtz to the department. In 1871, on behalf of the University of Berlin, Dubois-Reymond sent Helmholtz an offer to head the first department of physics in Germany. On February 13, 1871, returning from a trip to Switzerland, Helmholtz was invited to Versailles, where Wilhelm I signed his appointment as professor of physics. On this occasion, Dubois-Reymond remarked: “An unheard-of thing happened: a physician and professor of physiology occupied the main physics department in Germany.”

Soon Helmholtz was elected professor of physics at the Medical-Surgical Academy, the academy where he received his scientific education. Here, continuing his work on physiological acoustics and optics, he moved more and more away from medicine and moved on to purely physical issues. Shortly before this, Helmholtz received a request from William Thomson if he would like to take up the chair of experimental physics at Cambridge. The invitation is especially significant considering that the first professor of physics at Cambridge was the famous Maxwell and later the most prominent modern physicist, E. Rutherford.

During the Franco-Prussian War of 1873, Helmholtz took part in organizing assistance to the wounded. And in the same year, another family tragedy befell him: his daughter Kat died. Helmholtz had a hard time experiencing the loss of a loved one. But life moves on. On October 15, 1877, Helmholtz was elected rector of the University of Berlin and at the same time published the work “On Thinking in Medicine,” which has been of deep interest to this day. In 1888, he was appointed president of the Physico-Technological State Institution; He combined this position with a professorship in theoretical physics at the university until his death. Here he created works on physics, biophysics, physiology, and psychology. He developed the thermodynamic theory of chemical processes and introduced the concepts of free and bound energy. Laid the foundations of the theories of vortex motion of liquids and anomalous dispersion...

A year before his death, Helmholtz goes to the World's Fair in Chicago. Returning from a trip to America, he slipped while entering his cabin and injured his head, which apparently had serious consequences and could have caused subsequent illness. Paralysis of movements gradually developed, apparently due to the hemorrhage that continued to destroy the brain. Thus began the disease and severe events that led to death. On the morning of July 12, Helmholtz left the house, but was no longer able to walk on his own. A passerby ran up to him and helped bring him into the room and lay him on the sofa.

Despite the fact that Helmholtz supported the theory of the eternity of life put forward by Richter in 1865 (cosmozoan theory), death did not want to take this into account. The inevitable outcome of the life of all things on earth - death - took the brilliant scientist into its halls. This tragic event, which shook the entire scientific world, occurred on September 8, 1894 at 1 hour 11 minutes in the afternoon at the age of 72. A marble monument was erected in front of the University of Berlin, where the last years of the great naturalist’s life took place.

HELMHOLTZ, Hermann Ludwig Ferdinand

German physicist, mathematician, physiologist and psychologist Hermann Ludwig Ferdinand Helmholtz was born in Potsdam in the family of a gymnasium teacher. In 1838 he graduated from high school. Despite his interest in physics, Helmholtz was unable to enter university due to lack of funds. After signing a commitment to serve eight years as a military surgeon, he was accepted into the Friedrich Wilhelm Military Medical Institute in Berlin. In 1842, Helmholtz defended his dissertation on physiology; in 1843–1848. served as a military doctor in Potsdam. Here he became interested in physiology, which was taught by the famous physiologist I. Müller, and became close friends with young researchers E. Dubois-Reymond and E. Brücke, who were passionate about the idea of ​​​​transforming physiology as a science by introducing methods of physics and chemistry into it.

In 1845 Helmholtz became a member of the Berlin Physical Society. From that time on, he began to regularly travel to Berlin, where he conducted experiments in the laboratory of the famous physicist G. Magnus. In 1845–1846 The basic ideas of the scientist were formed, expressed by him in the famous work “On the Conservation of Force,” which became an important stage in the development of thermodynamics. On July 23, 1847, Helmholtz gave a report on this topic to the Physical Society. In it, he mathematically substantiated the law of conservation of forces (in modern scientific language - energy), showed its universality, introduced the concept of potential energy (in his terminology - tension force), connected the law of conservation of energy with the impossibility of building a perpetual motion machine. Having analyzed most of the physical phenomena known at that time, Helmholtz showed the universality of this law, in particular, that the processes occurring in living organisms also obey the law of conservation of energy; this was the strongest argument against the concept of a special “living force” supposedly controlling organisms. Somewhat earlier, the law of conservation of energy was formulated by the German physician Yu. R. Mayer, but his work was initially completely unknown to physicists.

In 1848, Helmholtz was released from military service, and he took the position of extraordinary professor of physiology and general pathology at the University of Königsberg. In 1855 he moved to the University of Bonn, and in 1858 he became a professor of physiology in Heidelberg. All this time, his studies in physiology continue. It measures the speed of propagation of a nerve impulse and studies the process of muscle contraction. Helmholtz becomes the first person to see the retina of a living person; for this he uses a special eye mirror - an ophthalmoscope, invented by him in 1850. His extensive research on the physiology of vision (theory of accommodation, color vision, etc.) was summarized in the classic work “Manual of Physiological Optics” (vols. 1– 3, 1856–1857). In 1856, Helmholtz's acoustic work began with the study of combination tones. He built a model of the ear, which made it possible to study the nature of the impact of sound waves on the organ of hearing, and solved the so-called problem. organ pipe, developed a theory of perception and production of sounds. In addition, he conducts important studies of the vibrations of strings and acoustic resonators (Helmholtz resonators), studies the hydrodynamics of vortices, and develops the principle of mechanical similarity, which makes it possible to explain a number of meteorological phenomena and the mechanism of formation of sea waves.

In 1870, Helmholtz was invited to Berlin, where the department and laboratory he headed became the informal center of physics in Germany. In 1888, he headed the Physico-Technical University, where both applied and fundamental research was carried out. Under the leadership of Helmholtz, the institute turned into a large scientific center, where young physicists from many countries, including Russia, came to study.

In 1870–1880 Helmholtz worked a lot on the problems of electrodynamics, trying to find criteria for choosing one of the then existing electrodynamic theories. Under his influence, G. Hertz conducted research that led to the discovery of electromagnetic waves. A major role in the development of electromagnetism was played by Helmholtz’s own experiments, carried out by him back in 1869. Drawing attention to the oscillatory nature of the discharge of a Leyden jar, he showed that similar oscillations arise in an induction coil connected to a capacitor (i.e., he essentially created an oscillatory circuit consisting of inductance and capacitance). In 1881, Helmholtz put forward the idea of ​​the atomic nature of electricity, in 1882 he formulated the second law of thermodynamics in a form that allows it to be applied to chemical processes, and introduced the concepts of free and bound energy.

HERMAN HELMHOLTZ

Hermann Helmholtz is one of the greatest scientists of the 19th century. Physics, physiology, anatomy, psychology, mathematics... In each of these sciences, he made brilliant discoveries that brought him worldwide fame.

Hermann Ludwig Ferdinand Helmholtz was born on August 31, 1821 in the family of a Potsdam gymnasium teacher. At the request of his father, in 1838 Hermann entered the Friedrich Wilhelm Military Medical Institute to study medicine. Under the influence of the famous physiologist Johann Muller, Helmholtz devoted himself to the study of physiology and, after attending an institute course, defended his doctoral dissertation in 1842 on the structure of the nervous system. In this work, the twenty-two-year-old doctor first proved the existence of integral structural elements of nervous tissue, which were later called neurons.

In the same year, Hermann was appointed as a resident at a hospital in Berlin. In 1843, Helmholtz began his career as a Potsdam military doctor. He lived in a barracks and got up at five o'clock in the morning at the signal of a cavalry trumpet. But the squadron surgeon of the hussar regiment also found time to study science. In 1845, he said goodbye to military service and went to Berlin to prepare for the state exams to become a doctor. Helmholtz studies diligently in the home physics laboratory of Gustav Magnus.

A.G. Stoletov, who sensitively grasped the turning point in the scientific development of Germany in the forties, wrote: “Magnus’s home laboratory - the first example of a physical laboratory - is becoming a breeding ground for experimental physicists.” Subsequently, a graduate of this laboratory, Helmholtz, becomes Magnus's successor and moves the laboratory to the building of the University of Berlin, where it turns into a world scientific center.

Another of Helmholtz's teachers in Berlin was Johann Müller. Much later, on November 2, 1871, at a celebration of Helmholtz on the occasion of his seventieth birthday, he made a speech in which he described his scientific path. He indicated that, under the influence of Johann Muller, he became interested in the question of the mysterious being of the life force. Reflecting on this problem, Helmholtz in the last year of his student came to the conclusion that the theory of vital force “attributes to every living body the properties of the so-called perpetuum mobile.” Helmholtz was familiar with the problem of perpetual motion from his school years, and during his student years “in his free moments... he looked for and looked through the works of Daniel Bernoulli, d’Alembert and other mathematicians of the last century.” “Thus,” said Helmholtz, “I came across the question: “What relation must exist between the various forces of nature, if we accept that perpetuum mobile is generally impossible?” - and further: “Are all these relations in reality fulfilled?”

In Müller's journal, Helmholtz published in 1845 his work “On the expenditure of matter during muscle action.” Also in 1845, young scientists grouped around Magnus and Müller formed the Berlin Physical Society. Helmholtz also joined it. Since 1845, the society, which later turned into the German Physical Society, began to publish the first abstract journal “Uspekhi Physics”.

Helmholtz's scientific development thus took place in a favorable environment of increased interest in natural science in Berlin. Already in the first volume of Uspekhi physics, 1845, published in Berlin in 1847, a review was published by Helmholtz on the theory of physiological thermal phenomena. On July 23, 1847, he made a report “On the Conservation of Force” at a meeting of the Berlin Physical Society. It was published as a separate brochure that same year.

The authorities at that time “were inclined to reject the justice of the law; amid the zealous struggle that they waged against Hegel’s natural philosophy, my work was considered fantastic intellectualism...” However, Helmholtz was not alone; he was supported by young scientists, and, above all, by the future famous physiologist Dubois Raymond and the young Berlin Physical Society.

As for his attitude to the work of his predecessors Mayer and Joule, Helmholtz repeatedly recognized the priority of Mayer and Joule, emphasizing, however, that he was not familiar with Mayer’s work, and did not know enough about Joule’s work.

Unlike his predecessors, he connects the law with the principle of the impossibility of perpetual motion. Helmholtz views matter as passive and immobile. In order to describe the changes taking place in the world, it must be endowed with forces of both attractive and repulsive. “The phenomena of nature,” says Helmholtz, “must be reduced to the movements of matter with unchanging driving forces, which depend only on spatial relationships.”

Thus, the world, according to Helmholtz, is a collection of material points interacting with each other with central forces. These forces are conservative, and Helmholtz puts the principle of conservation of living force at the head of his research. Helmholtz replaces Mayer’s principle “out of nothing nothing comes” with a more specific position that “it is impossible, given the existence of any arbitrary combination of bodies, to continuously obtain a driving force from nothing.”

The principle of conservation of living force in its formulation states: “If any number of moving material points moves only under the influence of such forces that depend on the interaction of the points on each other or that are directed towards fixed centers, then the sum of the living forces of all points taken together will remain the same same at all moments of time at which all points obtain the same relative positions in relation to each other and in relation to existing fixed centers, whatever their trajectories and velocities may be in the intervals between the corresponding moments.”

Having formulated this principle, Helmholtz considers its application in various special cases. Considering electrical phenomena, Helmholtz finds an expression for the energy of point charges and shows the physical meaning of a function called potential by Gauss. He then calculates the energy of a system of charged conductors and shows that when Leyden jars are discharged, heat is released that is equivalent to the stored electrical energy. He showed at the same time that the discharge is an oscillatory process and electrical oscillations “become smaller and smaller, until finally the living force is destroyed by the sum of the resistances.”

Helmholtz then considers galvanism. Helmholtz analyzes energy processes in galvanic sources, in thermoelectric phenomena, laying the foundation for the future thermodynamic theory of these phenomena. Considering magnetism and electromagnetism, Helmholtz, in particular, gives his well-known conclusion for the expression of the electromotive force of induction, based on Neumann's research and relying on Lenz's law.

In his work, Helmholtz, unlike Mayer, pays the main attention to physics and only speaks very briefly and concisely about biological phenomena. Nevertheless, it was this essay that opened the way for Helmholtz to the Department of Physiology and General Pathology of the Medical Faculty of the University of Königsberg, where in 1849 he received the position of extraordinary professor.

Helmholtz held this position until 1855, when he became a professor of anatomy and physiology in Bonn. In 1858, Helmholtz became a professor of physiology in Heidelberg, where he worked extensively and successfully on the physiology of vision. These studies have significantly enriched the field of knowledge and practical medicine. The result of these studies was the famous “Physiological Optics” by Helmholtz, the first issue of which was published in 1856, the second in 1860, and the third in 1867.

The eye is one of the most remarkable organs of our body. They knew about his work before and compared it with the work of a photographic camera. But to fully clarify even just the physical side of vision, a rough comparison with a camera is not enough. It is necessary to solve a number of complex problems from the field of not only physics, but also physiology and even psychology. They had to be resolved with a living eye, and Helmholtz managed to do this. He built a special device (ophthalmometer), amazing in its simplicity, which made it possible to measure the curvature of the cornea on the posterior and anterior surfaces of the lens. This is how the refraction of rays in the eye was studied.

We see objects painted in one color or another, our vision is colored. What is it based on? A study of the eye has shown that the retina has three main light-sensing elements: one of them is most irritated by red rays, the other by green rays, and the third by blue rays. Any color causes a stronger irritation of one of the elements and a weaker irritation of the others. Combinations of irritations create the entire play of colors that we see around us.

To examine the bottom of the living eye, Helmholtz made a special device: an eye mirror (ophthalmoscope). This device has long become mandatory equipment for every eye doctor.

Helmholtz did a lot to study the eye and vision: he created physiological optics - the science of the eye and vision.

Here, in Heidelberg, Helmholtz conducted his classical studies on the speed of spread of nervous excitation. Frogs for dissection visited the scientist’s laboratory table many times. He studied the speed of excitation propagation along the nerve. The nerve received irritation from the current, the caused excitation reached the muscle, and it contracted. Knowing the distances between these two points and the time difference, you can calculate the speed of excitation propagation along the nerve. It turned out to be very small, only from 30 to 100 m/s.

It seems like a very simple experience. It looks simple now that Helmholtz developed it. And before him, it was argued that this speed cannot be measured: it is a manifestation of a mysterious “vital force” that cannot be measured.

Helmholtz did no less to study hearing and the ear (physiological acoustics). In 1863, his book “The Doctrine of Sound Sensations as the Physiological Basis of Acoustics” was published.

And here, before Helmholtz’s research, much related to hearing was studied very poorly. They knew how sound originated and propagated, but very little was known about the effects that sounds have on objects capable of vibrating. Helmholtz was the first to tackle this complex phenomenon. Having created the theory of resonance, he then created on its basis the doctrine of auditory sensations, our voice, and musical instruments. While studying the phenomena of oscillations, Helmholtz developed a number of questions that are of great importance for the theory of music, and gave an analysis of the causes of musical harmony.

The example of Helmholtz shows the great importance of the breadth of a scientist’s horizons, the richness and diversity of his knowledge and interests. There, in Heidelberg, his classic works on hydrodynamics and the foundations of geometry were published.

Since March 1871, Helmholtz became a professor at the University of Berlin. He created a physics institute where physicists from all over the world came to work.

After moving to Berlin, Helmholtz devoted himself exclusively to physics, and studied its most complex areas: electrodynamics, in which, based on the ideas of Faraday, he developed his own theory, then hydrodynamics and the phenomena of electrolysis in connection with thermochemistry. Particularly remarkable are his works on hydrodynamics, begun back in 1858, in which Helmholtz gives the theory of vortex motion and fluid flow and in which he manages to solve several very difficult mathematical problems. In 1882, Helmholtz formulated the theory of free energy, which solves the question of what part of the total molecular energy of a certain system can be converted into work. This theory has the same meaning in thermochemistry as Carnot's principle in thermodynamics.

In 1883, Emperor Wilhelm granted Helmholtz the title of nobility. In 1884, Helmholtz published the theory of anomalous dispersion, and a little later several important works on theoretical mechanics. Works on meteorology date back to the same time.

In 1888, Helmholtz was appointed director of the newly established government physical and technical institute in Charlottenburg - the Center for German Metrology, in the organization of which he took an active part. At the same time, the scientist continues to lecture on theoretical physics at the university.

Helmholtz had many students; Thousands of students listened to his lectures. Many young scientists came to work in his laboratory and learn the art of experimentation. Many Russian scientists can be considered his students - physiologists E. Adamyuk, N. Bakst, F. Zavarykin, I. Sechenov, physicists P. Lebedev, P. Zidov, R. Colley, A. Sokolov, N. Shidder.

Unfortunately, not only joyful events awaited Helmholtz in his old age. His son Robert, a promising young physicist, died untimely in 1889, leaving his work on the ray emission of burning gases.

The scientist’s most recent works, written in 1891–1892, relate to theoretical mechanics.

Helmholtz Helmholtz (Hermann Ludwig Ferdinand von Helmholtz) is one of the greatest modern naturalists, b. in Potsdam on 19 Aug. 1821 At the request of his father, in 1838 he entered the Friedrich Wilhelm Military Medical Institute to study medicine; under the influence of the famous physiologist