The balloon-riding Victorians who courted disaster: the true story behind The Aeronauts

Who was James Glaisher?

The more senior of the two was the fabulously bewhiskered scientist James Glaisher, the superintendent of the Magnetic and Meteorological Department at the Royal Observatory at Greenwich, who would go on to be a founder member of the Aeronautical Society of Great Britain.

His co-pilot was Henry Coxwell, a highly experienced balloonist. The day’s flight was one of many the men had made together – part of a series of 28 balloon ascents commissioned by the British Association for the Advancement of Science.

What were Glaisher and Coxwell trying to achieve?

Glaisher and Coxwell’s mission was to measure the temperature and humidity of the atmosphere to better understand how this governed the weather – perhaps the scientist saw himself as a latter-day Christopher Columbus or Ferdinand Magellan, keen to explore what he called the “aerial ocean”, which offered him “a boundless sea of enquiry”.

The weather that September day proved to be kinder than on earlier attempts, especially two months earlier when the pair’s flight plans had been scuppered by unusually high winds for July.

At three minutes past 1pm, they released the tethers of their balloon, named Mars, and the upward voyage began. Glaisher was delighted that, on this windless afternoon, they rose “with the ease of an ascending vapour”. The balloon climbed two miles in just 19 minutes, aided by the potent gas supply ‘brewed’ by the manager of the nearby Wolverhampton Gas Works.

Glaisher and Coxwell’s mission was to measure the temperature and humidity of the atmosphere to better understand how this governed the weather

Once airborne, Glaisher the scientist set about his work. One experiment was to observe how high altitude affected the pigeons he had brought along, so as the balloon reached three miles high, he scooped up a bird and threw it over the side. Glaisher watched as it “dropped like a piece of paper”. A second pigeon, released at the four-mile mark, “flew vigorously round and round, apparently taking a dip each time” then a third was forced to take to the air between four and five miles, but “fell downwards as a stone”.

Glaisher didn’t heed these warnings.

How did disaster nearly strike Glaisher's balloon flight?

As the balloon continued to rise and the temperatures fell, Glaisher began to feel the effects of the thin air himself. His sight became fuzzy, his limbs grew heavy and immovable, and he could not even call out to Coxwell for help.

Soon, Glaisher had passed out, his head hanging over the basket. “In an instant, darkness came over me,” his memoirs reported. “I believed I would experience nothing more as death would come unless we speedily descended.”

No descent was imminent. Coxwell realised he would have to make the dangerous climb out of the basket and into the balloon’s rigging in order to free the valve line, which had become entangled. It was a crucial piece of equipment as it released gas from the canopy, which in turn allowed the balloon to descend.

Coxwell’s first attempt to untangle the valve line ended with an ungraceful tumble back into the basket while experiencing temperatures of minus 20 degrees Celsius. The balloon continued to rise. When he tried again, he had no feeling in his fingers due to the cold. Desperately, he clamped his teeth around the rope and forcefully tugged. The balloon’s ascent slowed and within a few seconds, the descent began.

With the immediate danger now past, Coxwell’s attention could now turn to Glaisher. He initially thought his partner to be resting due to his semi-recumbent position but, after realising the severity of the situation, Coxwell anxiously tried to rouse the unconscious man. “Never shall I forget those painful moments of doubt and suspense as to Mr Glaisher’s state when no response came to my questions,” he later wrote. “I began to fear he would never take any more readings.”

His efforts, though, were met with success. “I have been insensible,” declared Glaisher, with typically Victorian understatement, on regaining consciousness. “You have,” confirmed a relieved Coxwell. “And I too very nearly.”

Glaisher’s recovery was swift – reporting that “no inconvenience followed my insensibility” – and the first thing he did was to pick up his pencil to continue his readings. Successful scientific endeavour was paramount and certainly not to be dented by the mere trifle of a near-death experience.

That was, at least, until he noticed that Coxwell had not gone unaffected. His co-pilot’s hands were black from frostbite so Glaisher immediately sought a remedy, rubbing brandy into the hands until circulation was restored.

The last reading Glaisher made before falling unconscious had been at 29,000ft. Although his calculations that the balloon carried on above 36,000ft are almost certainly flawed (both men would surely have perished at that height), the confirmed height was still higher than anyone else had managed before.

As they headed back to terra firma, Glaisher released a fourth pigeon, but it simply hitched a ride atop the balloon. The pair landed in a farmer’s field in Shropshire, 20 miles from the launch site. Since, as Glaisher subsequently moaned, “no conveyance of any kind could be obtained”, he was forced to walk seven miles to the market town of Ludlow to find help. Coxwell stayed behind to look after the balloon as, after a previous landing in the area, the aeronauts had encountered hostility from locals annoyed at potential damage to crops.

Was Glaisher and Coxwell's flight a success?

Despite the high drama on board, the flight had been an unqualified success – and not only for the altitude reached. The readings from the ascent provided the first direct indication of the existence of the stratosphere, and, as Glaisher’s great-grandson John L Hunt has noted, the events of the day “was one of the first practical examples of the effect of the lack of oxygen on the human body”.

Glaisher, as the scientist and project leader, is rightly celebrated for the achievement, but there is a danger of downplaying Coxwell’s contribution. After all, he was the man who ensured the balloon didn’t disappear into the atmosphere and who revived his colleague.

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In the days after they reached for the skies, the duo’s travails were chronicled and lauded by the press. The ascent was the lead story in The Times and Punch magazine celebrated the feat in verse:

‘Tis true that these two men did go
Six miles towards the sky;
But as for Icarus, we know
That story’s all my eye.
Then what’s the use to hear about
Old heroes’ fabled acts
When now they’re beaten out and out
By wonders that are facts.

And what of the two remaining pigeons? Both landed with the balloon – one dead, but the other, after a short recovery, escaped to the sanctuary of the Shropshire countryside. It would never fly so high again. And neither would Glaisher and Coxwell.

This article was first published in the December 2019 issue of BBC History Revealed