The Gravity Engine

by Andrew May

First published in Quantum Muse, July 2000

It was with some trepidation that I left my house in Gloucester Square that warm summer’s evening in 1851. After all, it is not every day that one has an appointment with a madman. Yet the correspondence I had exchanged with Mr Faraday over the previous months had given birth to a profound curiosity in me; a curiosity that would only be satisfied by a personal meeting. I feared the man’s enthusiasm was becoming infectious.

As I walked across the tree-lined square, I reflected on what little I actually knew of Michael Faraday. He had vanished from public view in the thirty-odd years since his ignominious dismissal from the Royal Institution. Yet at the start of his career he had been a rising star in the field of science; a potential genius by some accounts. Everything changed with his disastrous researches into magnetism. Faraday had become obsessed with the preposterous notion that magnetism and electricity were in some wise interchangeable; that magnetism could be generated by electricity and vice versa. He fostered some crack-pot scheme for a motor that would turn his "electro-magnetism" into rotational energy like a fantastic species of steam engine. In the space of a few brief years Faraday saw all his ideas discredited by experiment, and found himself ostracised by the scientific establishment.

Judging from his letters to me, Faraday’s thoughts during his long scientific exile had turned from magnetism to gravity, the most ubiquitous and unchanging force in the world around us. Yet he spoke of harnessing its powers in the service of society. Surely this too was nothing but the continued raving of a lunatic? I strove to ground myself in reality, as I made my way across the leafy spaces of Tyburnia. Like its sister Belgravia further south, this was among the first districts in London to be planned from the start on both aesthetic and functional principles. Elegant four-storey town houses, with their stuccoed facades and Doric porches, lined the broad squares and avenues. It all seemed a far cry from talk of anti-gravity and inertialess motion.

I arrived at the busy thoroughfare of the Edgware Road and hailed a hackney cab. I recognised the driver, a jolly fellow with a red waistcoat and a gap in his front teeth.

"Good evening, Mr Stephenson sir," said he. "And where might I take you today?"

"Waterloo Bridge, at the junction with Commercial Road," I replied, for such was the location of my planned rendezvous with Mr Faraday. I climbed into the cab, and we moved off into the traffic, joining the general mass of cabs, carts and carriages clattering southwards.

In a few minutes we were heading down Park Lane, and for the hundredth time that year I found myself peering through the trees to my right to catch a glimpse of the vast wonder occupying a sizeable acreage of Hyde Park. Officially known as "The Great Exhibition of the Works of Industry of All Nations", it was a veritable Crystal Palace of steel and glass, more than a third of a mile in length, and a fitting tribute to the great Industrial Revolution in which my father, and more latterly I myself, had been privileged to play a modest role.

"Ain’t it a marvellous sight, Mr Stephenson," my driver said. "Have you visited inside it yet?"

"Indeed I have," said I. "And for my sins, I was asked to contribute a little to the exhibit concerning railways."

"Really, sir?" The cabbie looked impressed. "I wouldn’t have thought you had any time for that sort of thing these days, what with you being a Member of Parliament and all."

"On the contrary," I exclaimed. "I consider myself to be an engineer first and last. The country already has more than enough politicians. I view my seat in the House of Commons as an opportunity to further the interests of my fellow engineers, and to do my best to ensure that this great country of ours remains at the forefront of industrial progress."

We turned into Piccadilly, and then slowly made our way along the Haymarket, around Trafalgar Square, and into the Strand. If such a thing is conceivable, the traffic became even denser and more chaotic as we travelled east. In common with many such journeys, we experienced several near accidents as the driver, cursing under his breath, narrowly averted collisions with other vehicles. It has been suggested that all traffic should be made to drive on the left-hand side of the road, thus avoiding dispute as to who has right of way. But the sharply cambered roads, and the manure and other detritus piling up towards the gutters, mean that in reality anything but the middle of the road is treacherous for the horses. Perhaps Mr Faraday had the right idea indeed with his gravity-defying machines; a horseless carriage flying above the streets would be the perfect solution to London’s traffic problems!

From the Strand we turned off down Wellington Street and then onto Waterloo Bridge. Below us, the Thames was as busy with barges, steamboats and sailing boats as the streets were with carriages. The tide was low, and the water was a dirty pale brown. The stink was atrocious; the same rank odour that comes up from the sink-holes in the street. Instinctively I covered my nose with a handkerchief. I glanced at the cabbie; he seemed oblivious to the smell.

Ahead of us, on the south bank of the river, the building work for the great new southern rail terminus was visible on the upstream side of the bridge. On the downstream side rose the enormous spire of the Surrey Shot Tower, dwarfing everything around it. At a hundred and eighty feet, it was equal in height to Nelson’s Column on the more fashionable north side of the river, and to my mind much more attractive because it was functional as well as decorative.

At the far end of the bridge I alighted and paid the driver a shilling. As I watched the cab turn round and disappear into the traffic, I suddenly felt rather foolish. A solitary, smartly-dressed, middle-aged gentleman, alone on an unfamiliar street corner in Lambeth, waiting for an excommunicated scientist with a reputation as a charlatan and a lunatic! I took out my watch and flipped it open. It was only twenty past seven, still ten minutes before the time I had agreed to meet Mr Faraday.

A few minutes later I espied a figure shuffling purposefully towards me along Commercial Road. Dressed in rumpled grey clothes and with straggling white hair, the intensity of his gaze nevertheless convinced me that this was the man I had come to meet.

"My dear Faraday, it’s so good to make your acquaintance at last," I greeted as he came up to me.

"At your service, Mr Stephenson," he replied. "I cannot tell you how grateful I am that you have agreed to see me tonight. Please, follow me. There is much that I wish to show you, and I have no desire to take up more of your time than is absolutely necessary."

Faraday started to lead me back the way he had come. I warmed to his straightforward manner immediately. He had a noticeable Yorkshire accent, which endeared him to me still further. Although my work kept me in London most of the time, I was and always will be a Northerner at heart.

"My theories on electromagnetism were wrong, and I paid dearly for that mistake," said Faraday. "Since then I have conducted many more experiments, and I believe I have now made the breakthrough I was seeking. Yet my reputation is such that no-one in the scientific establishment is prepared to give me so much as a hearing. It is my fondest hope that you, with your practical knowledge of engineering and your position in Parliament, will be able to take my ideas forward in a way that I myself never will. There is a chance, and I believe it is a fairly good chance, that a machine will come of this that is every bit as revolutionary as your late father’s invention."

I said nothing. I had become accustomed, as indeed my father became accustomed in his later years, to hearing him referred to as the inventor of the steam locomotive. It served no great purpose to point out that what my father had actually done was to refine and develop a machine that had already been invented by the Cornishman Trevithick.

We turned off Commercial Road down an alley leading to the waterfront. I realised then that our destination could be nothing other than the Shot Tower itself.

"I needed a tall building for my experiments," Faraday explained. "To this end I secured a menial job for myself at this place. During the day I polish newly made shot and sort it into bags. I have been fortunate enough to gain the sympathy of the superintendant, and he allows me use of the building in the evenings on the condition that everything is back in good order by the next morning."

We arrived at the entrance to the tower, where a large ornately lettered signboard left one in no doubt that these were the premises of the Patent Shot Manufacturing Company. Faraday produced a large iron key and unlocked the door.

The inside of the tower was as impressive as the outside. About thirty feet across at the base, it tapered upwards to the top of the tower, where there was located a metal grille. During the normal course of operation, molten lead would be poured through this grille to plummet the hundred and eighty feet to ground level. In the middle of the floor was a large vat of water, designed to break the fall of the by now almost perfect spheres of molten lead, and cause them to cool and solidify into pieces of shot.

Looking up, I could see some sort of object suspended beneath the grille, attached by a rope which passed over a pulley arrangement.

"That is a pig of lead, weighing a hundred and seventy pounds," Faraday said. "Wound around it is an insulated copper wire, the two ends of which are then twisted around the rope supporting it. The rope passes over the pulley, then descends down to ground level where it passes around this winch."

Faraday indicated a large drum with a crank handle near the wall of the tower. The rope, with the two wires wrapped around it, was wound several times around the drum. The free ends of the two wires then passed through the hub of the drum, and a length of twisted wire protruded from it.

Faraday wheeled over a small table on which was placed an instrument made of brass and polished wood. I recognised it as an electro-calorimeter, a device commonly used for measuring electric current. I have a very similar thing in my own collection. Invented by a brilliant young gentleman from Salford by the name of James Prescott Joule, it works on the principle that a measurable amount of heat is generated whenever an electric current is passed through a resistance. The instrument makes use of a precisely known resistance, the heat capacity of which is also precisely known, together with an accurately calibrated thermometer which can measure temperature changes of small fractions of a degree.

Faraday picked up the free ends of the wire and clipped them onto the electro-calorimeter. "For the first experiment, I will simply release the brake on the winch. This will allow the weight to fall freely under gravity, pulling the rope and wires after it. What I have discovered is that some of the gravitational energy that is lost by the weight as it falls can be converted into electric current. Observe the meter carefully."

I glanced nervously up at the pig of lead, and then at the vat of water far below it.

"Oh, there is no need to worry," said Faraday, sensing my discomfort. "We will not get very wet if we keep close to the wall."

Faraday released a lever on the winch, and the lead weight began its descent. It took just over three seconds to make the journey to ground level, unravelling the rope from the winch with increasing speed as it fell. It landed in the vat with an enormous splash, emptying quite a quantity of water onto the surrounding floor in the process. But as Faraday had predicted, only a few spots reached us where we stood.

All this I heard in passing behind my back, for my attention was focused on the scale of the electro-calorimeter. As the weight descended, the mercury level jumped up by a significant fraction of an inch, then subsided back to its original value soon after we heard the splash. The fall had indeed produced a sizeable electric current.

Faraday turned to me, his eyes sparkling. "This was the first of my discoveries; that it is indeed possible to convert mechanical motion into electricity," he said. "Previously, the only method we have had to create electricity is the chemical cell, which is expensive and cumbersome. The generation of electricity will be revolutionised."

"That is a remarkable discovery indeed," said I. "But you implied that it is just the first of two that you have made."

Faraday disconnected the electro-calorimeter and pushed it away. He wheeled up a second table, on which stood a large battery of electrical cells. "The conversion of gravitational energy into electricity is reversible," he said, clipping one wire to the negative terminal of the battery. "Observe what happens when I close the circuit."

Faraday connected the other wire to the positive terminal. I looked anxiously at the vat of water, somehow expecting to see the pig of lead shoot up out of it and ascend heavenward. Nothing happened.

"Try pulling gently on the rope," Faraday said.

I took hold of the rope just above the winch, and gave a small tug. I felt a slight resistance as the lead weight rose up out of the water, but then all resistance vanished. I let go of the rope in surprise, but the weight continued its ascent. It appeared to rise at constant speed until it clattered against the pulley at the top of the tower, finally arresting its motion.

"Good Heavens," I exclaimed. "Anti-gravity!"

"I believe it is not just gravity that is neutralised, but inertia itself; the resistance of a body to any change in its motion," said Faraday. "This experiment used a lead weight, but it might just as well have been a steam engine. Just imagine; a locomotive flying through the sky as light as a bird."

I was suddenly put in mind of some lines by our new poet laureate. "What is it that Mr Tennyson says in Locksley Hall? About how he saw the heavens fill with commerce, argosies of magic sails…"

"…and the nations’ airy navies grappling in the central blue," continued Faraday. "Yes, anti-gravity will shape the future of commerce, and war, and everyday travel; everything will shift from the Earth’s surface to the skies above us."

My mind filled with visions. "We are standing on the brink of a revolution which will make the steam engine look old-fashioned," I said. "Who can guess what the world will be like a hundred and fifty years hence?"

"By the start of the twenty-first century, even the crustiest old professors will be preaching anti-gravity as if it is the most obvious thing in the world," Faraday said. Suddenly his mood darkened. "But if some creative young thinker ever makes so bold as to suggest a connection between electricity and magnetism – ah, that will be a different matter entirely. Then the guardians of scientific orthodoxy will foam at the mouth like mad dogs, and damn him as if he were possessed by demons."

Copyright © 2000, 2001 Andrew May