“With your back to the wind a low pressure center will be to one’s left, high pressure to one’s right” – C.H. D. Buys Ballot
One hundred sixty years later, we still remember this simple phrase. As campers, outdoors people, military members, boaters, or just looking up at the sky; with a simple glance we can guess whether a storm is coming or going. But, how did that phrase come about? Over several weeks I sailed around uncharted waters, digging through journals from the 1870s only to be swept back to books from the 1840s. What I came away with blew me away. A story of two men, half a world away, with the same idea. One relentlessly pushing his ideas and theories while the other published in a friend’s journal. In the end what I thought was a ‘law’ turned out to be something completely different.
William Ferrel
In 1856 William Ferrel wrote “An Essay on the Winds and Currents of the Ocean”for the Nashville Journal of Medicine and Surgery[1]. I won’t get into the details about how Mr. Ferrel knew the publisher of the journal, why he chose that journal over others; or just why he decided to publish his thoughts. These questions can all be answered by reading his biography. However by reading his article one can surmise a few things from his thought processes: Mr. Farrel drew his meteorological inspiration from James Epsy’s The Philosophy of Storms[2], along with the the theory behind his high/low storm rotations from Redford, Reid and Piddington’s books. After reading M.F. Maury’s The Physical Geography of the Sea[3], William Ferrel saw that there was a pattern with the charts and data that was presented in the book. Using George Hadley’s Theory concerning the cause of the general trade winds[4] and LaPlace Tidal Equations, he drew many conclusions, the most important being that of barometric pressure of storm systems in relation to the rotation of the earth. In 1858 he followed up in the Astronomical Journal with “The Influence of the Earth’s rotation upon the relative motion of bodies near its surface”[5]. This paper concluded the following: “If a body is moving in any direction, there is a force arising from the earth’s rotation, which always deflects to the right in the northern hemisphere, and to the left in the southern hemisphere”.
When one start to dig into William Ferrel, or the ‘Ferrel Cell’ they are presented with ‘Coriolis Effect’. However if they read more into the Coriolis Effect, or read William Ferrel’s article, he clearly states that the math he used in conjunction with Maury’s book was Laplace’s Tidal Equations from 1776 which, does resemble Coriolis Acceleration, 100+ years later.
William Ferrel wasn’t just known for his ‘Ferrel Cell’, and sadly the history books will probably only remember him as the ‘Coriolis Effect’ guy. But what people might not realize is that William Ferrel also built the first tide predicting machine in the US for the US Coast and Geodetic Survey. This machine predicted tidal highs and lows, running from 1883 until 1910. It was aptly named The Coast and Geodetic Survey Tide Predicting Machine No. 1.[6]
C.H.D. Buys Ballot
Whereas William Ferrel received his inspiration from the authors of the New World, Buys Ballot’s inspiration blew in from Europe. Buys Ballot’s brainstorm for his thesis, and later pamphlet, came from reading Wilheim Heinrich Dove’s Ueber Das Gesetz Der Sturme (On the Law of Storms)[7]. It can be assumed that if Buys Ballot had read W.H Dove’s book, he had also read the inspiration behind it; Henricus Guilielmus Brande’s Dissertatio physica de repentinis variationibus in pressione atmosphaerae observatis (Physical Dissertation on the Sudden Variations which have been observed in the Pressure of the Atmosphere)[8]. Both W.H. Dove and Henricus Brande go into detail about barometric low pressure storms and the direction of wind following the pressure systems. Likewise, both of these authors provided hard data, just like the author’s of William Ferrel’s book; however they never empirically proved their theories. This is what Buys Ballot aimed to do.
Not only did Buys Ballot conduct his own independent research for his thesis, he also reached out to other cities and countries across Europe to create a massive telegraph weather station system. Each station would report in their wind speed, direction, temperature and barometric pressure. If there were approaching storms, his telegraph stations would report this information to the other stations as an early warning system.
After gathering the necessary data, Buys Ballot released his thesis in 1857 titled: “Note sur se rapport de l’intensite et de la direction du vent avec les ecarts simultanes du barometre”[9]. His thesis was released 10 months after William Ferrel, however if you read his thesis, it says nothing of what one thinks of today: ‘back to the wind low pressure on left’. His original thesis in 1857 was on how changes in barometric pressure causes an increase in wind. The faster the barometer changes the faster the wind blows. Which, leaves one to wonder, where DID ‘Buys Ballot Law’ come from?
In 1860 Buys Ballot put out a pamphlet to the general public titled: “Eenige regelen voor aanstaande weersveranderingen in Nederland” (A few rules for forthcoming weather changes in the Netherlands)[10]. Okay, quick sidebar under the storm tree. Have you noticed that William Ferrel published all of his work in English; And yet in the 1800s Buys Ballot’s work is either published or studied in: English, German, Latin, French and now Dutch? Mr. Ferrel may have had an uphill battle with his theories, but Buys Ballot did have a world stage with 5 languages. This may have made it easier to disseminate his thesis and later, his ‘law’ as it was, across many scientific journals.
Buys Ballot’s pamphlet was meant as a general guide to the layperson for weather, from rain and pressure, to our current ‘Ballot phrase’. (On page 50 – Translated very rough from Dutch. I speak and understand many languages, Dutch is not one of them so forgive me if I butchered this)
The rule for the wind direction is thus this: Put yourself in the direction of the wind with your back to the wind. From where the wind comes, the lowest place is on left hand side; just as with hurricanes.
De regel voor de windrigting is dus deze : legt men zich in de rigting van den wind met den rug naar de plaats, van waar hij komt, zoo heeft men de laagste plaats aan de linkerhand, even als bij de orkanen.
Now the pieces are starting to come together. Or so you think. It was not just a thesis in 1857 to the scientific community about wind speed and barometric changes, but a simple weather pamphlet to the Dutch people in the 1860’s that spawned the ‘Buys Ballot Law’.
‘Back to the wind, Back to the wind…’ I had read this before, several years before 1860. While going through Henry Piddington’s The Sailor’s horn-book for the law of storms[12],he references a direct quote from Nautical Magazine of December[13], The Maria Soame’s Hurricane:
We left you with the first fair wind of a hurricane, from which you were to ascertain at once the direction of the focus from you. The method we gave you was good and simple, but perhaps the following may be more so. Turn your back to the wind ; then if you are in North latitude it will be on your left hand, but if you are in South latitude it will be on your right, in both cases at a right angle from the direction in which you are looking.
From this, at least 15 years before Buys Ballot published his pamphlet, one can assume that two important books on marine storms considered this common mariner knowledge. Does this necessarily mean that Buys Ballot came up with a new theory? I don’t believe so. Like many in his day, Including Ferrel; he took the research, theories, books of others and came across a central theme. He gave this theme life, nurtured it, and it became a common ‘law’ among meteorologists. However, he should be rightfully known for his original thesis on storms, wind direction and atmospheric pressure; not a re-printed quote from another author.
As with William Ferrel, many will remember him for his Law, but Buys Ballot should be remembered for much more. Mr. Ballot was an advocate for weather forecasting and alerts. His research into his thesis spanned several years, gathering data via telegraph from remote weather stations, which eventually spawned telegraph weather stations across other parts of Europe. He was also outspoken in meteorological circles on putting remote weather stations on islands and remote areas to gather storm data and report this data to Europe as an early warning system. His ideas were revolutionary at the time, and paved the way to weather stations across Europe.
Aftermath
By the early 1860’s we have two brilliant meteorologists; worlds away. Students from two different schools of thought. One focused on the American and British authors; publishing to an obscure journal of medicine. And the other, a follower of European authors, publishing to international mediums.
After Ferrel published his articles he went on to study, research and publish several more articles into the 1880’s. This is where Mr. Ballot differs from Mr. Ferrel. Where Mr. Ferrel researched and published, Mr. Ballot did the same but also advocated, attempted to sway the scientific community to his theories and generally did everything in his power to advance the meteorological community in Europe. This didn’t go unnoticed in Europe, because during this time there was a power struggle between meteorologist theories and eventually something needed to become a standard. This is where R.H. Scott of the Royal Meteorological Society stepped in. R.H. Scott had read Mr. Ballot’s previously published articles. After reading his articles he became a convert of his theories and proposed the two idea’s from Buys Ballot’s thesis papers to the Royal Meteorological Society on May 1868 titled “Report of an Inquiry into the connexion between strong winds and barometrical differences[11]” presented to the committee of the meteorological office. This is one of the first times that these two theories were put together in the same article, being called ‘Buys Ballot Law’.
It wasn’t until 1886 that Ballot wrote to William Ferrel. And in an extremely difficult to find return letter on 25 July 1886, Mr Ferrel wrote back:
I cannot but admire your great generosity in proposing to connect my name with yours and even to put mine first in designating the law known as Buys Ballot’s law The law has been too long and too well known by the latter designation to change it now if there was any occasion for it But there is really none No one doubts its being an original discovery with you and first promulgated by you and if as frequently happens in new discoveries others may have similar ideas about the same time this is no occasion why the name of the law should be changed Although I would esteem it a great honor to have my name in any way connected with yours yet I will never encourage the change which you so generously propose C.H.D Buys Ballot. [14]
And there it is, the seas have calmed, and all is right in the world. Buys Ballot realized that William Ferrel had come up with his theory earlier and was willing to give him the credit he deserved. But, William Ferrel realized changing the name of a theory that has been known around the world for over 20 years would not be beneficial to the meteorological community. They were men of science, knowledge, desire to further not only their studies, but advance the meteorological age for their respective continents. What an amazing journey through turbulent seas, a whirlwind of languages, essays and laws to only be presented with the calm sea of understanding between two scientists. As I dock this gondola of knowledge, I leave the reader with this: If two scientists half a world away came up with the same theories at the same time 150 years ago; what other scientific discoveries were made, published or otherwise by doppelgänger’s?
Written by: Jayson Broughton – Edited by: Len Kaplan
Bibliography
1: William Ferrel, An essay on the winds and the currents of the ocean, 1856
2: James Pollard Espy, The Philosophy of Storms, 1841
3: M.F. Maury, The Physical Geography of the Sea, 1855
4: George Hadley, Concerning the cause of the general trade winds, 1753
5: William Ferrel, The Influence of the Earth’s Rotation Upon the Relative Motion of Bodies Near It’s Surface, 1858
6: B.G. Fischer, The Coast and Geodetic Survey Tide Predicting Machine No. 2, 1912
7: Heinrich Wilheim Dove, Ueber Das Gesete der Sturme, 1857
8: Henricus Guilielmus Brande, Dissertatio physica de repentinis variationibus in pressione atmosphaerae observatis, 1826
9: Buys Ballot, Note sur se rapport de l’intensite et de la direction du vent avec les ecarts simultanes du barometre, 1857
10: Buys Ballot, Eenige regelen voor aanstaande weersveranderingen in Nederland, 1860
11: R.H. Scott, Report of an Inquiry into the connexion between strong winds and barometrical differences presented to the committee of the meterological office, 1869
12: Henry Piddington, The Sailors horn-book for the law of storms, 1851
13: The Nautical Magazine of December, The Maria Soames’ Hurricane, 1846
14: J.P. Van Der Stok, Levensbericht C.H.D Buys Ballot, 1899
