1743: Hales invents first mechanical ventilator

Stephen Hales (1677-1761)
 (1, page 328)

Stephen Hales was among the great men of science who lived during the 17th century. Among other achievements, he was the first to accurately measure blood pressure, and he invented an artificial ventilator used to purify air for people living in enclosed quarters such as prisons, ships, and granaries.

He was born in 1677 into the world of Isaac Newton (1643-1727), the man who inspired the scientific revolution.  When Hales was only a boy of ten-years-old, Newton was at the peek of his career, publishing his book Philosophiæ Naturalis Principia Mathematica (Mathematical Principals of Natural Philosophy). It was in this book Newton published his laws of motion and laws of universal gravitation. Such wisdom, when he learned about it in school, must have inspired the young Hales. (4, page 66)

A young Hales would also have been influenced by Robert Boyle and John Mayow.  Boyle's was a great chemist (some say alchemist) who was best known for his use of the scientific method and creating Boyle's law, which states the inverse relationship between absolute pressure and the volume of gas.  Mayow was such a great mind that, had he not died prematurely at the young age of 35, might have been the first to discover oxygen and carbon dioxide.  (4, page 66-67)

As those great men set a path for men like Hales, he would do the same for those who followed in his tracks, such as Joseph Black, who discovered carbon dioxide, Joseph Priestly, who discovered oxygen, Carl Scheele, who also discovered oxygen, Lavoisier, who also discovered oxygen and gave it a name, and Henry Cavendish, who discovered hydrogen.

Hales entered Corpus Christi College, Cambridge, in 1696, and studied science, botany, and chemistry.  He was ordained in 1703, and he began his work on chemistry at the laboratory at Trinity College.  In 1709 he was appointed as minister to the Parish of Teddington, where he would spend the rest of his life. He was married in 1719, although his wife died in 1721.  He died at the age of 83 in 1761.  (4, page 65)(5)

His main contributions to science and physiology came in his Statical Essays that were published in two parts: Vegetable Statics, published in 1727 (the same year that Newton died), and Haemastaticks, published in 1733.

In Vegetable Statics he discussed plant physiology and chemistry.  Yet his most significant contributions to our history come from his later work Haemastaticks, which is described by britannica.com as the most significant contribution to the physiology of blood circulation since the works of William Harvey. (5)

In this book he described an experiment where he inserted a tube into a blood vessel and allowed blood to rise up the tube.  In this way he became the first person to "quantitatively measure blood pressure." (5)

He also described measuring the capacity of the left ventricle of the heart, the output of the heart per minute, and the speed and resistance to flow of blood in the vessels.  (5)

He became very interested in the spread of disease, and was aware that people in close quarters were more likely to catch diseases because they were all breathing the same stale air. Infections were easily spreading from one person to another.  (2, pages 241-243)

Of course in his day, once you caught a disease such as tuberculosis, you were at the whim of God, meaning that there was little you could do but pray that you got better.

So he set out to invent something that could be installed at these places to ventilate air from the outside in order to freshen the air inside.  What he ended up inventing was the first artificial mechanical ventilator which he introduced to the public in 1743.

He published his invention and opinions in his 1758 book "Treaties on Ventilators."

Sir John Simon wrote about "English Sanitary Institutions" in 1897, and explained how the invention of Stephen Hales benefited people who spent time in prisons, military barracks, military hospitals, and aboard ships.  He said:

Dr. Hales's "lungs"... seem to have been often advantageously used in ships, prisons and hospitals (the military was) ordered by the Lords of the Admiralty to adapt his "fire-pipes" to His Majesty's Navy 4 Readers of the present day who may find it hard to imagine the " putrid " quality of the atmospheres which in those days the inmates of prisons and ships and barracks and hospitals had to breathe, can well assist their imagination by referring to the pages of Hales and other contemporary reformers. (3, page 119)

John Pringle (1707-1782)
(1, page 374)

The invention was helped along by John Pringle, who was a surgeon general of the British Army from 1742-1758, and considered the father of modern military medicine. (1, page 373)

He studied the spread of disease among the military, particularly fevers.  He observed, along with others, that the more people were in a confined space, the greater likelihood the spread of fevers would be.  (2, pages 241-3)

Attributing it to the stale air inhaled, he championed to have the mechanical ventilator described by Hales installed in hospital wards.  (2, pages 241-3)

He discussed the importance of military sanitation, especially the importance of the mechanical ventilator, in his 1752 book "Observations on the Diseases of the Army." He also wrote about the importance of antiseptics to prevent the spread of disease. (1, page 373)

The problem with the ventilator was electricity hadn't been invented yet, and so the machine had to be man powered.  So, not only was the machine itself expensive, it was expensive to work and maintain. (1, pages 241-3)

So many military hospital wards resorted the difficult task of maintaining wards in well ventilated places such as "barns, churches, or ruinous houses.  Of  course the simplest and least expensive solution was simply to keep patients in the same poorly ventilated wards they were already in.   (1, pages 241-3)

When this was the case, many such institutions worked hard to install as many windows as they could into such places.  When new places were built, as many windows as possible were installed.  Windows, therefore, were the least expensive option to improve ventilation, and by the late 1750s most hospitals had plenty of windows.  (1, pages 241-3)(2, pages 241-243)

Of course, Pringle also said there was an increased effort to try to keep patients separated.  This, along with better ventilation from open windows, seemed to help allay the problem, at least to a certain degree.  (2, pages 241-3)

It got to the point that there are stories of patients who were lying sick in bed looking up through the holes in the ceiling at the stars and moon in the night sky, or feeling the hot sun upon their bodies during the day.  This must have been a nice, refreshing atmosphere to get healthy in.

However, when the weather wasn't so friendly, such a venue must have posed a problem, especially when the rain or snow was falling.

To sum up the contributions of Hales I will quote Dr. Garrison:

Stephen Hales (was) an English clergyman of inventive genius, who enriched practical science in many ways, particularly as the originator of artificial ventilation."  (1, page 328) 

References:

1. Garrison, Fielding Hudson, "Introduciton to the history of medicine," 1922, London, W.B. Saunders Company
2. Hudson, George L, "British Military and Naval Medicine, 1600-1830," 2007, Amsterdam, New York, Editions Rodopi B.V.
3. Simon, John, "English Sanitary Institutions," 1897, 2nd edition, London, John Murray
4. Darwin, Francis, edited by Francis Wall Oliver, "Makers of British Botany," 1913, London, Cambridge University Press
5. "Stephen Hales," britannica.com, http://www.britannica.com/EBchecked/topic/252340/Stephen-Hales, accessed 7/11/14

RT Cave Facebook Page
RT Cave on Twitter

1636: Boyle learn benefits of artificial breathing

Robert Boyle (1627-1691)

1637:Boyle learns benefits of artificial breathing

By his accurate anatomical descriptions, Andreas Vesaleas inspired a generation of physicians to learn about the human body.  He also did some experiments himself, one of which included his using bellows to push air into the trachea of an animal.  This experiment was later used by Robert Hooke to prove that artificial respiration could be used to keep a person alive.

In 1636 Robert Boyle (1627-1691) discovered the presence of gases in the blood, and is therefore perhaps the first to describe an element. He found that "fresh defibrinated blood gave off bubbles of gas when it was exposed to the vacuum of an air pump."

A few years later John Mayow (1640-1679) thought the gas was nirto-aerial gas, or what we now refer to as oxygen.  (7, page 517)

Boyle, on the other hand, is responsible for many discoveries, his most famous being what is now referred to as Boyle's Law. 

This states that at a constant temperature the pressure of a gas has an inverse relationship to it's volume.

This law would become very significant to many of the later researchers. It would be used to explain why we breathe, why popcorn pops, why a tea kettle whistles, and why a balloon bursts when you blow too much air into it.

The same law would later be used by physicians to explain why inventions like Robert Hooke's bellows might cause trauma to the lungs.

1590: The invention of the microscope

The name of the person who invented glass will forever be unknown to history, although what is known is that it was invented in the first century by the ancient Romans. 

After grinding various shapes and sizes of lenses, they spent quite a bit of time looking through these, and they observed the some objects appeared larger -- were magnified -- when observed through certain lenses.  In this way, the ancient Romans discovered the first simple microscopes.

This knowledge, however, was not used much until the 13th century when spectacle makers ground different sizes and shapes of lenses in order to find a way to help people see better.  

While they invented the first spectacles, they also ended up inventing the first microscopes.  These first microscopes, however, were basically nothing more than large magnifying glasses.  

In 1590, two spectacle makers by the name of Zaccharias Janssen and his father Hans, were experimenting with various lenses.  They ended up putting one lens in a tube, and then two, and then three, to see how this might improve or change the appearance of objects observed. 

What they ended up discovering was the by using two lenses they could make an object appear 3-10 times larger than normal, and even larger than they appeared in any simple magnifying glass.  It was in this way that they invented the compound microscope.  

Soon after other investigators learned of this new invention, Galileo Galillei improved upon it by performing his own experiments.  He would use it to investigate the sun and the solar system.  

Jan Swammerdam and Robert Hook would also use it to investigate the unseen elements of the human body, making discoveries that would help advance medicine.  

Anthony Leeuwenhoek would also use a microscope, although the one he invented was a simple microscope that, because he became so adept at grinding lenses and adjusting light, was able to magnify objects far greater than any compound microscope, or up to 500 times.  

In this way, the microscope would become one of the most significant tools of science and medicine.

References:

1. Tissier
2. Lagerkvist, Ulf, "The Enigma of Ferment," 2005, Singapore, World Scientific Publishing
3. Potter, Elizabeth, "Gender and Boyle's Law of Gases," 2001, Indiana University Press
4. Newman, William R, et al, "Alchemy Tried in the Fire," 2002, University of Chicago
5. Lehrs, Ernst, "Man or Matter," 1958, Great Britain, Whistable Litho Ltd.
6. Jindel, S.K., "Oxygen Therapy," 2008, pages 5-8
7. Hill, Leonard, Benjamin Moore, Arthur Phillip Beddard, John James Rickard, etc., editors, "Recent Advances in Physiology and bio-chemistry," 1908, London, Edward Arnold
8. Hamilton, William, "A History of Medicine, Surgery and Anatomy," 1831, Vol. I, London, New Burlington
9. Osler, William Henry, "The evolution of Modern Medicine: A series of lectures delivered at Yale University on the Sillman Foundation in April, 1913," 1921, New Haven, Yale University Press
10. Osler, ibid, pages 170, reference referring to William Harvey: Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus, Francofurti, 1628, G. Moreton's facsimile reprint and translation, Canterbury, 1894, p. 48. 20 Ibid., p. 49.
11. Garrison, Fielding Hudson, "Introduction to the history of medicine," 1921, London, 
12. Baker, Christopher, editor, "The Great Cultural Eras of the Western World: Absolutism and the Scientific Revolution 1600-1720: A biographical dictionary," 2002, CT, Greenwood Publishing; Herman Boerhavve published Biblia Naturae (Bible of Nature) in 1737, which was a two volume compilation of the works of Jan Swammerdam. Can you read Latin?
13. Garrison, op cit, 266; (Samuel) Pepy's Diary, Mynors Bright's ed., London, 1900, v, 191
14. Bradford, Thomas Lindsley, writer, Robert Ray Roth, editor, “Quiz questions on the history of medicine from the lectures of Thomas Lindley Bradford M.D.,” 1898, Philadelphia, Hohn Joseph McVey
15. Brock, Arthur John, "Galen on the natural faculties," 1916, London, New York, William Heinemann, G.P. Putnam's Sons
16. "History of Chemistry," historyworld.net, http://www.historyworld.net/wrldhis/PlainTextHistories.asp?ParagraphID=kpt, accessed 7/6/14
17. Affray, Charles, Denis Noble, "Origins of Systems Biology in William Harvey's masterpiece on the Movement of the Heart and the Blood in Animals," April 17, 2009, International Journal of Molecular Sciences, 10(2), pages 1658-1669, found online at ncbi.nlm.hih.gov, http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2680639/, accessed 7/8/14

RT Cave Facebook Page
RT Cave on Twitter