Radium in the Two World Wars
In the late 19th century, German scientist Wilhelm Röntgen discovered a previously unknown form of powerful radiation invisible to the human eye. This type of ray, which no one (including Röntgen) fully understood at the time, was so mysterious that he named it ‘X’. In 1896, working from Röntgen’s findings, Henri Becquerel identified the phenomenon of radioactivity – both as a concept and as a force – and Marie Skłodowska Curie would later give it a name. In 1898, with her husband Pierre, Skłodowska Curie identified two new elements: polonium and radium.
Scientists and, in turn, medical practitioners and entrepreneurs would struggle to understand the complicated properties of these new radiations. By the early 1900s, the mostly unfathomable properties of radium would find expression in a wide range of products and services aimed at the general consumer. I have been logging examples of these on www.museumofradium.co.uk
One of the most important markets was radium paint. In their laboratory, the Curies had observed that while radium chloride looked just like salt it actually glowed in the dark. This effect was subsequently understood to be caused by its radiation agitating the nitrogen naturally present in the air. This vibration creates a buzz of energy, which is perceptible as a shimmer of light, just luminous enough to be visible in the dark. If you added a sticky substance to it, you could paint objects and make them glow and, because radium was continually giving off energy, this paint would not fade for a very long time.
In Britain, the biggest consumer of radium paint was the armed forces, starting with the Compass Department of the Admiralty. This department had begun using luminous radium compounds in 1914 for compasses but its use was soon expanded to other divisions for objects like aeroplane instruments (particularly advantageous as early aircraft did not have electrical systems), binoculars and escape hatches.
Watches with self-luminous dials became an essential safety element: a must-have gadget. They solved a very important problem – how to see your watch in the dark (a vital necessity for timed and synchronised manoeuvres) without calling attention to your location.
In the book Knowledge for War: Every Officer’s Handbook for the Front, written by Captain B.C. Lake and published around 1916, there was a list of indispensable items. First on this list – even before ‘Field glasses’ and ‘Revolver’ – is ‘Luminous wristwatch with unbreakable glass’.
Companies such as Ingersoll, The Goldsmiths & Silversmiths Company, J.C. Vickery, and Mappin & Webb sold luminous trench or ‘service’ watches. The Allies’ Wristlet Watch, sold by G. Baudoin in Paris, featured both unbreakable glass and a luminous dial: ‘Will victoriously withstand any shock, however violent. Indispensable at the front. Useful to all.’
Demand for self-luminous watches only grew after the war. The wearing of wristwatches by officers and soldiers (prior to the First World War it had been frowned upon for men to have anything other than a pocket watch: wristwatches were for women) had created a fashion that spread through wider society. While this change of fashion happened a little later the other side of the Atlantic, it has been estimated that over 4 million glow-in-the-dark watches had been produced in the United States by 1920.
Towards the end of the next decade as the inevitable descent into a second Europe-wide war began, the British government and Armed Forces again recognised the importance of radium-activated paints as part of the war effort.
And while trench warfare was no longer the primary driver, there was still a need for the glow-in-the-dark effect. Blackout regulations were imposed on 1 September 1939 and moving around the darkened streets of Britain was fraught with dangers and challenges that, the advertisers stressed, could best be solved by their products: ‘Night workers! Get an Ingersoll Radiolite Pocket Watch or Wrist Watch: Shows the Time in the Dark.’
As the dangers of using radium became better understood watchmakers sought alternatives. By the 1960s Tritium was used as an activator, followed by non-radioactive substances like LumiNova or Super LumiNova. These are ‘after glow’ pigments that grow very brightly after exposure to a light source but diminish over time.
Glow-in-the-dark radium watches are highly collectable and come onto the market in alarming numbers and, often, in poor condition. If you do happen to find yourself the owner of a radium watch it’s probably safe to wear it occasionally but my advice is: do not sleep with it and don’t place it on your bedside table at night.
Lucy Jane Santos is an expert in the history of 20th century leisure, health, and beauty with a particular interest in (some might say obsession with) the cultural history of radioactivity. She is the author of Half Lives: The Unlikely History of Radium, which is out in paperback now.