Citizen meteorology, Victorian style: the meteorological balloon ascents of 1852

One of the principal aims of Constructing Scientific Communities is to discover nineteenth-century models for twenty-first century citizen science projects, in which large numbers of people from various walks of life gather and analyse data under the direction of research scientists. A hitherto little-known example of nineteenth-century citizen science dates from 1852, when some private individuals, in addition to a handful of astronomers working in observatories, were invited to make regular observations of the weather during a series of four daredevil balloon ascents between August and November 1852.

The first serious scientific balloon flights in Britain, they were organised by the ‘Kew Committee’, a committee of the British Association for the Advancement of Science, which then ran Kew Observatory near London. Formerly the private astronomical observatory of King George III, Kew Observatory had been taken over by the BAAS in 1842 and it quickly became a powerhouse of innovative meteorological experiments, observations and instruments. It would soon become world famous as a centre for geomagnetic research, solar astronomy and instrument testing, as well as meteorology.

Reporting to the Kew Committee was the Scottish physicist John Welsh, superintendent of Kew Observatory from 1852 to 1859. Welsh personally went up on all four balloon flights and was in charge of the scientific observations. On the first two flights, he was accompanied by Richard Nicklin, an assistant observer at Kew. All the ascents were made in the large Nassau balloon that was owned and operated by Charles Green, the leading British balloon pilot, or ‘aeronaut’ of the time. Each flight was launched from Vauxhall Gardens, a well-known London pleasure resort for the well-to-do.

The principal scientific goal of these balloon flights was to measure the temperature and humidity of the air at different altitudes. As late as 1852, the properties of the upper atmosphere and the circulation of weather systems around the globe were poorly understood. Nor was there as yet any national weather service or system of professional weather stations as we have today. In order to obtain reliable comparisons with weather data on the ground, it was necessary to employ a large network of volunteer observers underneath where the balloon would be flying. The unpredictable winds at altitude meant that the path of the balloon could not be predicted in advance. For example, the first flight, launched on 17 August, ended near Swavesey in Cambridgeshire, yet on the last ascent (10 November), the balloon nearly landed in the English Channel, eventually coming to rest near Folkestone.

The volunteer observers were therefore scattered across a large area, to ensure that at least a few of them would be in the vicinity of the balloon’s flight path. The majority of the observers were in a wide range of locations across southern and eastern England, including Aylesbury, Bedfordshire, Norwich, the Isle of Wight, Oxford and Cambridge, as well as the London area. Results were also used from observers even further afield, in places such as Edinburgh and Belfast, likely so that a picture of the weather across the whole of Britain on the days of the ascents could be built up.


Example of a printed circular with instructions to volunteers taking weather observations on the ground during the balloon ascent of 17 August 1852. Reproduced by kind permission of the Syndics of Cambridge University Library, MS.RGO.6.402.457.

Prior to each flight, the Kew Committee sent out a circular, asking the observers to take readings of the barometer, hygrometer, and dry and wet thermometers every hour while the balloon was in the air. The circulars also requested the volunteers to note the types of cloud in the vicinity of the balloon (if the balloon was visible from their observing station), and to send in their regular weather observations for the days before and after each ascent. Ever committed to scientific precision, the Kew Committee even asked volunteers to send in the corrections they made to their instruments and their station’s height above the sea. The example illustrated here is the circular sent to the Astronomer Royal, George Airy, three days before the 17 August flight.

It is not known how the volunteers came to take part in this project, but it is likely that members of the Kew Committee wrote to a large number of people whom they knew to be active meteorological observers and invited them to contribute. Of the thirty-four observers who participated, six might today be described as ‘professional astronomers’. These included George Airy at Greenwich Observatory and Manuel Johnson of the Radcliffe Observatory in Oxford. Yet almost none of the rest did science for a living: they were mostly private gentlemen, a fair number of them clergymen with scientific interests.

At least some of the data produced by the observers were used in analysing the results of the ascents. Welsh’s paper describes how in order to compare the temperature of the air at different altitudes, it was necessary to measure the temperature on the ground along the track of the balloon. This was achieved by selecting and averaging the results from observers closest to the course of the balloon on each flight. The ground observers’ results were essential in demonstrating the drop in temperature with altitude. On 17 August, the balloon reached a maximum height of 19,000 feet, where a temperature of 10° Fahrenheit (-12°C) was recorded, while the mean temperature on the ground was 71° Fahrenheit (21°C).

It could be argued that the ground observations were mostly made by privileged individuals with time and money to do science. But the principle of using volunteer observers in support of a large scientific project was exactly the same in 1852 as that used in today’s citizen science projects such as those managed by Zooniverse.


James Glaisher (1809-1903). Source: Wikimedia Commons.

One of the ground observers was James Glaisher, head of the Magnetic and Meteorological Department at Greenwich. Welsh’s ascents in 1852 inspired Glaisher to carry out a series of even more daring meteorological balloon flights in the 1860s, which brought him national fame. Unfortunately, Welsh himself died in 1859, aged just thirty-four, which might be one reason why his pioneering work in 1852 – plus that of his airborne companions and the volunteer observers on the ground – is not so well remembered today. Yet the balloon experiments of 1852 paved the way for later studies of the upper atmosphere, in addition to acting as an inspiring exemplar of a research project in which private citizens provided much of the large body of supporting data required.

Dr Lee Macdonald is a historian of science in the nineteenth and twentieth centuries, specialising in the history of astronomy and the physical sciences. In addition to working part-time for the Constructing Scientific Communities project, Lee works as Research Facilitator at the Museum of the History of Science in Oxford.


The Victorian origins of ‘space weather’

Today we take it for granted that activity on the Sun causes colourful displays of the aurora (the ‘northern lights’ in the northern hemisphere; the ‘southern lights’ south of the equator) and, in extreme cases, power cuts and disruptions to satellite communications. We now know that the Sun triggers these phenomena through its magnetic field and the stream of subatomic particles it emits, called the ‘solar wind’ – which in turn affects Earth’s magnetic field. We call the state of the solar wind and magnetic activity in the solar system ‘space weather’. Aurorae do not just take place on Earth: they can occur on any planet that has both a magnetic field and an atmosphere. They have been photographed in the atmospheres of Jupiter, Saturn, Uranus and Neptune; more recently, spacecraft have imaged them in the skies of Mars.

We strongly associate pictures of aurorae on other planets, as well as terms like ‘space weather’ and ‘solar wind’, very much with the space age. However, the possibility of detecting aurorae on other planets – and, by implication, the existence of the Sun’s influence throughout the solar system – was first suggested by two British astronomers working in the mid-nineteenth century: Balfour Stewart (1828-1887) and Edward Sabine (1788-1883).

A correlation between aurorae and the Earth’s magnetic field had been known since the eighteenth century, when Anders Celsius (best known for the Celsius temperature scale) and Olof Hiorter noticed frequent and wild oscillations in the direction of magnetic north during an auroral display. In the 1830s, the astronomer and scientific polymath John Herschel (1792-1871) undertook a systematic study of sunspots while on a four-year observing expedition at the Cape of Good Hope in South Africa. In 1837, he noticed a peak in both sunspot and auroral activity and thought that it would be worth investigating whether a correlation between these two phenomena applied more generally. Six years later, German apothecary and astronomer Heinrich Schwabe discovered that the number of sunspots waxed and waned in a ten-year cycle. Then, in 1852, Sabine discovered a similar periodicity in the Earth’s magnetic field and noticed that it coincided exactly with Schwabe’s sunspot cycle. Herschel saw this discovery as confirmation of a link between sunspots and aurorae, and he now suggested that the ‘red clouds’ seen during a solar eclipse (now known as solar prominences) might be ‘reposing auroral masses’.

In response to Sabine’s discovery, the British Association for the Advancement of Science (BAAS) set up a solar telescope and a suite of magnetic instruments in the Association’s observatory at Kew, to further investigate this correlation. The solar telescope, known as the Kew ‘photoheliograph’, took pictures of the Sun every clear day so that sunspot activity could be compared with the magnetic readings. (See separate article and associated video on the ConSciCom web pages about Elizabeth Beckley’s role in solar photography at Kew.)

In 1859, Balfour Stewart became superintendent of Kew Observatory. On 1 September that year, just two months after Stewart took up his post, the astronomers Richard Carrington and Richard Hodgson independently noticed a pair of bright lights appear above a large sunspot group, only to disappear a few minutes later. The timing of this explosion on the Sun, now known to have been a solar flare, coincided exactly with a jump in the traces produced by the magnetic instruments at Kew, and triggered Stewart’s interest in connections between solar activity and terrestrial magnetism.

In the early 1860s, Stewart and Sabine engaged in a lively correspondence on the nature of the newly-discovered Sun-Earth connections. In an August 1862 letter to Sabine, Stewart revived (without acknowledgement) Herschel’s 1852 assertion that the red clouds seen during eclipses might be aurorae on the Sun. In his reply to Stewart, Sabine took the speculation further, suggesting that the solar ‘aurorae’ triggered aurorae on Earth and wondered whether ‘all the planets participate in such appearances, though we may never attain to their observation’. Stewart, in turn, suggested a variety of observational evidence in favour of the red solar clouds being aurorae, including the fact that, as with sunspots, their greatest frequency coincided with periods of magnetic disturbance on Earth. As to Sabine’s suggestion that aurorae might occur on all the planets, Stewart wondered whether ‘perhaps Mr De La Rue could photograph one [of the planets] during an Aurora and ascertain this’.

Warren De La Rue (1815-1889) was then Britain’s leading pioneer of astronomical photography. He was instrumental in designing the Kew photoheliograph and was famous for his photographs of the Moon. Neither De La Rue’s nor anyone else’s photographic technology was then capable of photographing aurorae on other planets, but since 1979 spacecraft, including the Hubble Space Telescope, have photographed aurorae around the poles of Mars, Jupiter, Saturn, Uranus and Neptune (though scientists believe that Jupiter’s aurorae are due primarily to the interaction of the planet’s magnetic field with its volcanic satellite Io rather than the solar wind).


Figure 1. Aurora around the southern pole of Saturn, photographed with the Hubble Space Telescope. Image courtesy J. T. Trauger (Jet Propulsion Laboratory) and NASA.

Although Sabine and Stewart’s prediction had to wait more than a century to be vindicated, their logic was correct: something emanating from the Sun was influencing the entire solar system at the same time. We now know that this ‘solar wind’ is made up of charged subatomic particles that become tangled in planetary magnetic fields and cause their atmospheres to glow with auroral light. What, however, could these two visionaries have had in mind in 1862, when the smallest particle known to exist was the hydrogen atom?

Stewart’s work makes it clear that he believed solar emissions travelled through an invisible, all-pervading medium called the ‘ether’. In the mid-nineteenth century, with the rise of the wave theory of light, such a medium had become a popular way of explaining how light travelled through space. In the forefront of this ether physics was Stewart’s contemporary and fellow Scot, James Clerk Maxwell (1831-1879), whose electromagnetic theory described mathematically how light is an electrical and magnetic wave that propagates through this hypothetical ether. The ether was needed in the wave theory of light, because as a wave, light needed something to propagate through, just as sound requires air in which to travel.

Moreover Stewart, a staunch Christian believer, saw the ether as a convenient way of explaining the newly-discovered law of the conservation of energy without compromising the religious doctrine that the universe would one day come to an end. The ether provided a repository into which all the energy in the universe would eventually be dissipated, leaving the universe ultimately devoid of light and heat.

Stewart believed that as the planets changed their positions relative to the Sun, they moved through this ether and drew energy out of the Sun, causing magnetic effects that gave rise to sunspots and, as a consequence, aurorae. According to Stewart, the ether meant that the Sun and planets were tightly bound to one another, so that the motion of one body would have an effect on the others. Over the 1860s and 1870s, he used the solar results at Kew to develop some increasingly elaborate theories that attempted to correlate the positions of planets in their orbits with variations in sunspot activity. At the same time, he built experiments to find evidence for the ether, by measuring the heating of a disc spinning rapidly in a vacuum, eliminating friction with the air as a source of heat.

Watch a short video taken in 2007 by the STEREO A spacecraft, showing the tail of Comet Encke being buffeted by the solar wind – thought by Balfour Stewart and his contemporaries to be due to the ether. (Courtesy of NASA/STEREO.)

Both these approaches had inconclusive results. Stewart claimed to have detected heating in his spinning disc experiments, though modern scientists believe that this was due to the less-than-perfect vacuum attainable with the equipment of the mid-nineteenth century. After 1905, the ether theory gradually became discredited by Albert Einstein’s special theory of relativity. This painted a new picture of how light waves travel through space, dispensing with the notion of an ether.

However, the story of Balfour Stewart’s researches into solar-terrestrial physics has one ironic twist. In 1870, Stewart left Kew to become professor of ‘natural philosophy’ (now called physics) at Owens College in Manchester (now the University of Manchester). One of his students at Manchester was a young Joseph John (‘J. J.’) Thomson, who in 1897 would discover the electron – the first of the subatomic particles now known to make up the solar wind.

Dr Lee Macdonald is a historian of science in the nineteenth and twentieth centuries, specialising in the history of astronomy and the physical sciences. In addition to working part-time for the Constructing Scientific Communities project, Lee works as Research Facilitator at the Museum of the History of Science in Oxford.

‘Work peculiarly fitting to a lady’: Elizabeth Beckley and the early years of solar photography

The important role played by female photographic assistants in American astronomical observatories at the end of the nineteenth century is now well-known – and, indeed, has recently been popularised by Dava Sobel, in her 2016 book, The Glass Universe: How the Ladies of the Harvard Observatory Took the Measure of the Stars. These assistants carried out the tedious, but essential work of analysing images of stars and stellar spectra on photographic plates. Some of them became major pioneers of astronomy in their own right – notably Henrietta Leavitt, whose discovery of the period-luminosity law of Cepheid-type variable stars enabled Edwin Hubble and his successors to measure the distance scale of the universe.


Kew Observatory

Less well-known, however, is the work of British astronomical photographer Elizabeth Beckley (c. 1846-1927), who took photographs of the Sun and analysed the results two decades before Edward Pickering established his team of female assistants at Harvard College Observatory. Elizabeth Beckley worked at Kew Observatory near London, where members of the British Association for the Advancement of Science had set up a ‘photoheliograph’, a small refracting telescope dedicated to photographing the Sun and its mysterious dark spots. In the 1840s, a German pharmacist and amateur astronomer called Heinrich Schwabe had discovered that the number of sunspots visible waxed and waned in a cycle of approximately ten years. Then, in 1852, soldier and geophysicist Edward Sabine found that variations in the Earth’s magnetic field rose and fell in a cycle that coincided exactly with Schwabe’s sunspot cycle. Sabine then persuaded the BAAS to build a dedicated solar telescope and set it up at Kew, where it would be used from 1858 to photograph the Sun every clear day in an effort to understand the interrelation between the sunspot and magnetic cycles.

Putting this plan into practice was not easy, especially as Kew Observatory had a very limited budget. The Kew photoheliograph used what was then the latest photographic technology, a process known as ‘wet collodion’, which enabled sharp images of the Sun to be taken using snapshot exposures lasting tiny fractions of a second. This process, however, was very labour-intensive: the photographic plates had to be prepared immediately before exposure and then exposed and developed while still wet. Therefore, two people were needed to produce solar images: one to aim the telescope and take the pictures, the other to prepare and develop the plates. Yet the observatory did not have sufficient funds to employ two people.

Enter Elizabeth Beckley. Still in her teens when she began photographing the Sun in the 1860s, Elizabeth was the daughter of Kew Observatory’s mechanical engineer, Robert Beckley – himself an important figure in the history of meteorology for his role in developing the Robinson-Beckley anemometer, the familiar device with whirling cups that measures wind speeds on the tops of buildings. In 1870, Elizabeth Beckley married George Mathews Whipple, an assistant at Kew Observatory who became its superintendent in 1876. They had two sons, of whom the eldest, Robert Stewart Whipple (1871-1953), became a noted scientific instrument collector and the founding donor of the Whipple Museum of the History of Science in Cambridge.

In 1865, Elizabeth Beckley’s involvement in solar photography was acknowledged by Warren De La Rue, who had taken a leading role in designing the photoheliograph. De La Rue claimed that solar photography:-

seems to be a work peculiarly fitting to a lady. During the day she watches for opportunities for photographing the Sun with that patience for which the sex is distinguished, and she never lets an opportunity escape her. It is extraordinary that even on very cloudy days, between gaps of cloud, when it would be imagined that it was almost impossible to get a photograph, yet there is always a record at Kew.

It is likely that Sabine had some part in employing Miss Beckley, for there is evidence that he wanted Robert Beckley himself to select an assistant to help him with the photographic work. It seems that Beckley, not having the money to employ a full-time assistant, used his daughter as casual labour. Significantly, Elizabeth Beckley’s name does not appear on any of the observatory’s annual salary lists. Yet a diary kept at Kew in the 1860s reveals occasional payments of £5 to ‘Miss Beckley’, suggesting that she was paid piecemeal.



Indeed, it is not difficult to imagine a father-daughter partnership at work in photographing the Sun at Kew. De La Rue’s article quoted here suggests that Elizabeth might have watched for precious intervals of clear sky and operated the photoheliograph, while her father prepared the plates and developed them after exposure. It is also possible, though, that this team effort worked the other way round, with the father taking the photographs and the daughter working in the darkroom.

In any case, this seems to be the earliest example of a woman being employed in the day-to-day work of astronomical photography. Although women did not have a recognised role in scientific photography in the 1860s, they were very active by then in the burgeoning field of commercial photography. Some prominent portrait photographers of the mid-nineteenth century were women – such as Julia Margaret Cameron, who took portraits of many prominent people of the time, including the elderly Sir John Herschel. Also, by the early 1870s, many assistants working in photographic studios were women.

Elizabeth Beckley’s work might therefore have reflected a contemporary trend, though her work as an astronomical photographer was pioneering in the 1860s – especially when we consider evidence that in addition to taking the photographs, she helped to analyse the results. Those results were used by the observatory’s director, Balfour Stewart, to make tentative correlations between planetary alignments and sunspot activity, and to effectively predict what we now call the ‘solar wind’, a flow of matter and energy from the Sun that causes ‘storms’ in the Earth’s magnetic field and displays of the aurora borealis or northern lights. Elizabeth Beckley’s photographic work played a direct role in establishing the modern science of solar-terrestrial physics.

Watch an interview with Dr Lee Macdonald on Elizabeth Beckley for International Women’s Day:

Dr Lee Macdonald is a historian of science in the nineteenth and twentieth centuries, specialising in the history of astronomy and the physical sciences. In addition to working part-time for the Constructing Scientific Communities project, Lee works as Research Facilitator at the Museum of the History of Science in Oxford.