“[…] I think, together with Claude Bernard, that movement is the most important act, in that all the functions come into play in order to achieve it.”[i]
(Fig. 1) Marey, Etienne Jules (1830-1904)
Marey had a long and distinguished scientific career covering more than 50 years, focusing principally on the study of movement. In all its forms, he tried to record and track movement in order to better deconstruct, dissect, and analyze its functionality in medicine, physiology, and biomechanics. Instruments, appliances and machines, images and chronophotographs[ii], devised and fabricated, attest to his scientific abilities and imagination. Marey very soon realized that most of the advances made in the experimental sciences, as in the sciences of pure observation, result from the methods and instruments used. The creation of a large number of measuring instruments, linked with the graphical representation of physiological signals, reveals the origins of most of his scientific discoveries. After studying at the Faculty of Medicine in Paris, in 1859, he defended his medical thesis on blood circulation in physiological and pathological conditions. Already, his thesis showed the premises of his passion for engineering and physiology.
The advances achieved in the science of physical diagnosis were a feature of nineteenth century trends. Indeed, auscultation and percussion established themselves as the chief preoccupations in research into signs of disease. Following this trend, manufactured and tested measuring instruments in order to better interpret and apply the results of experimental physiology to medicine[iii]. He was particularly interested in the hydraulics of blood circulation, body heat, and respiration, the movements of the heart, muscular function, nervous actions, and electrical phenomena. In the early 19th century, Marey’s scientific preoccupations became part of the thinking in which vitalism and positivism materialism stood out in providing explanations for the characteristics of life. For the first group, life depended on a vital force inherent in living tissue and distinct from conscious thought. The latter group, the positivists, rejected these theories, asserting that the laws of physico-chemistry governed the functioning of the living matter.
However, the recovery of the laws of thermodynamics to explain the movement of living beings put an end to this debate. The logic of materialism steered physiological tests on demonstrations of calorific, mechanical, electric and chemical forces, thus building new bridges between the disciplines by raising conceptual and theoretical standards. Marey followed this eclectic path; he devised, developed, and constructed apparatus using an intellectual method which consisted of borrowing from the different systems and keeping what seemed most probable and positive in each. He founded a new coherent system in which concepts, theories, methods, and borrowed instrumentation contributed to establishing a new approach and discipline: biomechanics.
The originality of Marey’s work can be seen in the recording of movement by means of the invention and creation of multiple and diverse measuring instruments[iv]. The various sensors, linked to graphics, show motor function but do not
reveal its complexity. They contribute to the biomechanical analytical and methodical deconstruction of animal and human functions, movement and locomotion. This kinematic and dynamic tracking of motion helps to address hidden physiological assumptions. It is true that the movement and locomotion of living beings is determined by their anatomical constitution which should be shown in order to better understand and exploit physiological knowledge. In this respect Marey was to exploit other fields of research in multiple domains, electricity, photochemistry, chronophotography that would introduce bionics.
Marey also referred to the past and took inspiration from it. His collection of studies entitled La Machine Animale [Animal Mechanism][v], published in 1873 reveals, in its numerous quotations from Borelli’s work as far back as the late seventeenth century, how biomechanics is descended from the iatromechanical movement. The Animal Mechanism, a transitional work between medical writings (in particular on blood circulation) and specifically physiological writings in an approach directed towards understanding the motor function (La méthode graphique [The graphic method][vi] 1878, Levol des oiseaux [The flight of birds][vii], 1890) is surprising in its interpretation of the functionality of the body, mainly organological, not to say exclusively mechanical (pumps, valves, tubes, mechanical support).
Marey’s interest in movement was inscribed in the context of the application of the laws of energy conservation. With Animal Mechanism he, again like his predecessors, compares the organism to a machine, whose organs are its parts, each function (respiration, circulation, locomotion) associated with its own machine represented by the corresponding organs.
Movement represents one of the most apparent characteristics of life, both in terms of blood circulation and in terms of movements that are subject to the will, which regulates their speed, energy and duration by the muscular actions of locomotion. To analyze and understand the laws that govern movement, the spatial and temporal relationships should be established while at the same time the underlying forces should be clearly demonstrated.
However, at that time, transitional movement was proving difficult to analyze without resorting to methods taken from physics and chemistry. Hence Marey created new tools that were to initiate the graphic method, facilitating interpretation until laws could be extracted. His scientific approach puts forward a fundamental angle, that of proving laws by simulation using mechanical models, capable of reproducing the phenomena being observed and analyzed.
This approach or methodology, closely associating analysis and simulation, was very modern. Indeed, nowadays this method is part of the analytical and algorithmic approach favored by the rise in the use of computers. Marey designed and built many models, notably for blood circulation and to pump the heart[viii], but also for the flight of birds, locomotion remaining a complex activity difficult to model.
One of the striking aspects of Marey’s experimental legacy seems to be the transition towards the use of chronophotography, which progressively supplanted his graphic method. Having studied the work of the British photographer Eadweard Muybridge (1830-1904), who in 1878, invented a process capable of deconstructing and fixing movement, Marey decided to concentrate his research on developing equipment that would make it possible to carry out chronophotography.
(Fig. 3) From the book, Movement (1895). Method of simultaneously recording the foot-pressure on the ground and the changes in elevation of the body during a jump. Courtesy of Collection BIU Health Medicine, Open License.
However, feeling that his system was too cumbersome and complicated, he devised a photographic gun in 1882. He drew inspiration in particular from the gun of the astronomer Jules Janssen (1824-1907), used in 1874 to photograph planet Venus crossing the Sun. This instrument made it possible to take twelve photographs per second. In 1893, he succeeded in projecting deconstructed images, which was to become the technical origin of cinematography. In particular, with this method he obtained images with equal time intervals between the positions. All these processes enabled this French research scientist to dissect in slow motion the different phases in human and animal locomotion. All this extensive work on time, space, locomotion, was to be recorded in his book Le Mouvement [Movement][ix], published in 1894.
Marey’s scientific project focused on understanding the laws that produce movements, because they encapsulate life, and understanding them means gaining an understanding of life.[x] For that purpose, he used chronophotography which facilitated the description and measurement of the global properties of movement in order to reach an understanding of the physiological mechanisms underlying their production.
For example, the global chronophotographic and kinematic description of a vertical jump gives information about the parabolic trajectory of the center of gravity. This trajectory makes it possible to calculate the work generated, but above all to estimate the muscular force of the lower limbs. The recording of the force exerted on the ground, with the development of pneumatic capsules and later the creation of a force platform, dictated to Marey that every muscular act that results in raising the body’s center of gravity increases the pressure exerted on the ground.
Marey’s work, through the exposure of all the measuring instruments he created, shows the connecting thread and the logical progression of his ideas that cross through anatomical considerations and physiological processes. The observer can deduce, by picking up and registering mechanical signals, the physiological sources. The process materializes movement in order to better quantify it and facilitate its understanding. In particular, the energy expended is calculated to measure the efficiency or the deficiency of the underlying physiological mechanisms.
For E-J Marey, physiology should be made part of the dialogue between anatomy and mechanics so as to produce, together with these partners, a new scientific discipline, biomechanics. Indeed, his work was conducted in the late nineteenth century, in a favourable social context and economic environment where sciences were combining to create new ones.[xi]
In this context, the close association of eclecticism and inventiveness found itself transcended by influences from industry and the technical positivist culture. This trend favored the association of multidifferentiated and multi-referenced concepts and theories, to create new lines of thought. Marey’s inventions draw inspiration from technical and industrial social reality which is interested in calculating the efficiency of living engines and the rationality of the laws of energy saving. This explains the inventiveness of heterogeneous, varied, and precise apparatus to measure blood circulation, cardiac pulsations, lung movements, and also the displacement or falling of common objects, kinematics and the global locomotor dynamics of animals and humans.
Marey’s studies associated medicine and subsequently physiology not only with science and technology but also with art, showing his achievements in the light of pioneers in numerous subjects. In fact, he was to dedicate the last three years of his life, from 1899 to 1901, to a little known aspect of his work, the study of air motion by photography. Thus, through his aerodynamic research on smoke trails and the flight of birds, he contributed to making progress on questions directly related to the field of aeronautics which was just being born.
[i]Marey, Etienne-Jules. Du mouvement dans les fonctions de la vie.[Movement in the functions of life].Paris:G. Baillière, 1868.
[ii] Shell, Hanna Rose. “Cinehistory and Experiments on Film.”Journal of Visual Culture, 11 (2012): 288-306.
[iii]Lawrence,Christopher. “Physiological apparatus in the Wellcome Museum. 1. The Marey sphygmograph.”Medical History22 (1978):196-200.
[iv]Dagognet, François. Etienne-Jules Marey – A Passion for the Trace. New York: MIT Press, 1992.
[v] Marey, Etienne-Jules. Animal Mechanism: a treatise on terrestrial and aerial locomotion.New York: D. Appleton & Co., 1879.
[vi] Marey, Etienne-Jules. La méthode graphique dans les sciences expérimentales et principalement en physiologie et en médecine.[The graphic method in the experimental sciences and more specifically in physiology and medicine]. Paris: Masson, 1878.
[vii] Marey, Etienne-Jules. Le vol des oiseaux. [The flight of birds]. Paris: G. Masson, 1890.
[viii]Silverman,Mark. “Etienne-Jules Marey: 19th century cardiovascular physiologist and inventor of cinematography.”Clinical Cardiology, 19 (1996): 339-41.
[ix]Marey, Etienne-Jules. Movement. New York: D. Appleton and Company, 1895.
[x]Douard,John W. “E.-J. Marey’s visual rhetoric and the graphic decomposition of the body.” Studies in History and Philosophy of Science Part A, 26 (1995):175-204.
[xi]Baker, Richard. “The history of gait analysis before the advent of modern computers.”Gait & Posture, 26 (2007): 331-342.
Figure 1. Public Domain, via biusante.parisdescartes.fr / Image reference: CIPB2106
Figure 2. Public Domain, via biusante.parisdescartes.fr / Image reference: CIPB2106
Figure 3. Public Domain, via biusante.parisdescartes.fr / Image reference MEDIC@: medmarey106x0167
PHILIPPE CAMPILLO, PhD, after a thesis obtained in 1998 at Montpellier University in STAPS (Science and Technology of Physical and Sports Activities) on the biomechanical analysis of specific sport movements, he completed a second doctoral graduate level at Lille University in the discipline “Epistemology, history of science and technology”, on the theme: the history of the theories of locomotion. His perspectives and research interests are: analysis and optimization of motor performance / history and epistemology of science and biomechanics of locomotion.