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Physicists and Physicians Stories from the History of Medical Physics and Bioengineering

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Physicists and Physicians Stories from the History of Medical Physics and Bioengineering Physicists and Physicians Stories from the history of medical physics and bioengineering HPA Lecture 20th ICMP, Brighton September 1 2013 Francis Duck University of Bath, UK [email protected] Four stories of medical physics Giovanni Borelli (1608-1679) Italian astrophysicist Bryan Robinson (1680-1754) Irish physician Jules Gavarret (1809-1890) French medical physicist Edith Stoney (1869-1938) British medical physicist Thomas Young Neil Arnott Herman von Helmholtz Ferdinand Monoyer Adolf Fick Carlos Matteucci Emil du Bois- Reymond Golding Bird John Draper Published 2013: 306 pages ISBN 978 1 903613 55 9 Institute of Physics and Engineering in Medicine, Fairmount House 230 Tadcaster Road, York, YO24 1ES, UK Giovanni Pisa Borelli (1608-79) “I undertook this work … to enlist Anatomy into Physics” “If the spine of a stevedore is bent and supports a load of 120 pounds carried on the neck, the force exerted by Nature in the intervertebral disks and in the extensor muscles of the spine is equal to 25585 pounds. The force exerted by the muscles alone is not less than 6404 pounds”. Is the heart on fire? • “To determine the temperature of the heart accurately, at Pisa, I took care of opening the chest of a live stag and immediately let a thermometer be introduced through the wound into the left ventricle of the heart. • I saw that the highest temperature of the heart did not exceed 40° (gradus 40) which is the usual temperature in the sun in the summer in our country. • Afterwards, using similar thermometers, I measured the temperature of the liver, lungs and intestines in the same stag alive. • It appeared that the heart has the same temperature as the other viscera” Publication of De Moto Animalium • De Moto Animalium was published in Rome in 2 volumes, in 1680 and 1681, just after Borelli’s death • Queen Christina of Sweden gave financial support “her generosity provided the poor Author with considerable funds to improve his destiny and for his work.” • Borelli’s scientific philosophy: he quotes Plato’s reply to the question “What does God do?” : “God exerts geometry”. Not all physicians agreed that iatrophysics was helpful “The Greatest Numbers of Professors of Medicine are declared Enemies to it , and make nothing of breaking their Jests upon Angles, Cylinders, Cones, Celerity, Percussion, Resistance and such like terms, which they say have no more to do with Physic, or the Human Body, than a Carpenter has to do in making Venice Treacle, or curing a fever” John Quincy, Medical Statica: Being the Aphorisms of Sanctorius Translated into English, 5th edition. London. 1737. Bryan Robinson (1680-1754) An Irish Newtonian Physician Robinson’s repetition of Santorius’ “insensible perspiration” experiment Studies on the properties of fibres •A human hair from a “a healthful young Woman 22 years of age” •The extension was measured after it had been held under tension for 2 minutes •Then it was “gently rub’d the Hair from End to End with a Feather dipp’d in some Fluid, and continued thus wetting it for one Minute” •Then the same tension for a further 2 minutes. •He tested the effects of 65 different liquids. “Sir Isaac Newton discovered the Causes of Muscular Motion, and Secretion; and likewise furnished materials for explaining Digestion, Nutrition and Respiration.” Bryan Robinson. A Treatise on the Animal Oeconomy. 1732. Dublin. Robinson’s “Newtonian” explanations Of muscular action: “begun in the nerves at their origin, has been proved to be the vibration of a very elastic fluid ……. by the Power of the Will, a vibrating Motion is excited in the Æther in those Ends of the Nerves which terminate in the Brain, that Motion is in a Instant propagated thro’ their solid and uniform Capillamenta to the Membranes of the Muscles, and excites a like Motion in the Æther lodged within those Membranes” Of secretion: “Sir Isaac Newton has proved from experiments that Particles of Light attract ardent spirits and oil more strongly than water”. Did Robinson misrepresent Newton’s views? • Newton’s Optiks Query 23: “Is not vision perform’d chiefly by the vibrations of this medium (the aether), excited in the bottom of the eye by the rays of light, and propagated through the … optick nerves into the place of sensation? • Newton’s Optiks Query 24 “Is not animal motion perform’d by the vibrations of this medium, excited in the brain by the power of the will, and propagated from thence through the … nerves into the muscles?” • Newton’s Optiks Query 30 “Are not gross bodies and light convertible into one another, and may not bodies receive much of their activity from the particles of light which enter their composition?” A definition of medical physics, 1814 Jean Hallé Professor of Medical Physics and Hygiene, Faculty of Medicine in Paris (1795-1822) Physics applied to • knowledge of the human body …, • to its conservation … • and to the cure of its illnesses. Jules Gavarret (1809-1890) The third Professor of Medical Physics at the Faculty of Medicine, Paris Jules Gavarret France 1809 Born at Astaffort, Lot-et-Garonne 1815 Battle of Waterloo 1824 King Charles X 1829-31 École polytechnique, Paris 1830 Revolution: King Louis-Philippe 1831-33 Military training 1833-40 Medical training in Paris 1840-44 Haematology research with Gabriel Andral 1844 Appointed as professor of medical physics 1847 Cross of the legion d’honneur 1848 Revolution ends monarchy nd 1860 Married Eudoxie Binesse 1852 Napoleon III: 2 Empire 1862 Officer of the legion d’honneur 1871 Siege of Paris 1872 3rd Republic 1885 Retired: made honorary professor 1885 Commander of the legion d’honneur 1890 Died Principes generaux de statistique medicale (1840) • Gavarret had attended a heated discussion on C-A Louis’ data on blood-letting with 140 typhoid patients. • “Navier’s discourse made clear his grasp of the subject and the judgements one could draw from the use of the principles of probability calculation in therapeutic research” • Gavarret applied Poisson’s probability calculations to Louis’ data. With a probability of just over 99.9 to 1, the true mortality rate could have been as high as 49% or as low as 26%. Charles- Claude- Alexandre Louis Siméon Louis Navier Poisson Becquerel’s thermocouple measurements Back’s Arctic measurements Regnault’s apparatus Books by Gavarret • 1840 Principes generaux de statistique medicale • 1855 De la chaleur produite par les êtres vivants • 1859 Traite de l’électricité • 1861 Télégraphique électriquea • 1866 Des images par réflexion et par réfraction • 1869 Physique biologique - Phénomènes physiques de la vie • 1877 Acoustique biologique – Phénomènes physiques de la phonation et de l’audition Is this wide and beautiful theory of reciprocity of forces general enough to encompass the dynamic appearances of the organized world as well as those of the inorganic world? Must it, in a word, be accepted to be universal? These are ideas on which we place reliance, so as to push back, as a mere useless hypothesis, the existence of that independent directing force exerted on the body which, under various names, the vitalist school invoke to explain the phenomena of nutrition and development. Gavarret and medical education • 1872 Strasbourg medical school closed and moved to Nancy • 1873 Gavarret appointed as inspector of preparatory medical schools to review upgrade to full faculty status. • 1874 Preparatory schools at Lyons and Bordeaux converted to full Faculties. • 1879 Gavarret appointed as Inspector-General for Higher Medical Education Professors of medical physics in French Medical Faculties Monoyer, Ferdinand (1836-1912) Lyon Imbert, Armand (1850-1922): Montpellier Charpentier, Augustin (1852-1916) Nancy Bergonié, Jean-Alban (1857-1925) Bordeaux Number of general medical physics books published per decade 6 5 4 3 France 2 Other countries 1 0 Biological physics syllabus • fluid mechanics and the circulation • pneumatics and respiration • optics and vision • acoustics and speech and hearing • heat and body temperature • dynamics and animal mechanics • electricity and bio-electrics • energy and metabolism He was by nature a true scientist, and I always knew him as a freethinker. And, if … his funeral honours did not conform in this regard to his ideas …. he might blame, no doubt, that impersonal posthumous tendency that is so easily assumed, without conscious thought or interest, under the cover and apparent benefit of outmoded, although sacred, customs. Voltaire himself did not escape M Laborde 1890 Edith Stoney MA (1869-1938) Edith Stoney’s family Cousin Father Distant cousin George FitzGerald FRS George Johnstone Stoney FRS Alan Turing (physicist) (physicist) (mathematician) Brother Brother Edith Sister Sister Gerald Stoney FRS Robert Stoney Stoney Florence Stoney Gertrude Stoney (engineer) (doctor) OBE (radiologist) (artist) Edith Stoney’s life • Born 6 January 1869: Donnybrook, Dublin. • 1890-94: Newnham College Cambridge. First class in Maths Tripos Part 1. • 1895-98: Mathematics teacher, Cheltenham Ladies College • 1899-1915 Lecturer in Physics, London (Royal Free) School of Medicine for Women • 1915-1919 Medical military service during WWI • 1919-1925 Lecturer in Physics, Household and Social Science Department, King’s College for Women. • 1925-1938. Retirement work with the British Federation of University Women • Died 25 June 1938: Bournemouth Edith Stoney as a mathematical physicist “The problems she has attacked and solved have been in relation to the special curvature of mirrors for obtaining beams of light of particular shapes. These investigations involved
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