Edward Davy and the telegraph

All I can say is hooray for Ken Slater and Clive Coogan, who drew my attention to a gap in my knowledge -- by the time I had finished plugging it, these two talks had come into being.

People who write, complaining, commending or commenting to the ABC may sometimes feel that the bouquets and brickbats they cast have left not a ripple. This is the story of how one set of brickbats about Australian content led one ABC talk-maker down some curious historical by-ways.

Now the people who program music for the ABC have to worry about Australian content, but I never thought it would be a problem for the Science Unit. I was wrong, it seems.

Under the Australian content system, music programmers must include a certain percentage of Australian music, either composed or performed in Australia, and this probably helps to keep a number of local musicians and composers out of the soup kitchens.

But the logic is odd, as John Cargher reminds us from time to time, for the system claims almost anybody with an Australian affinity: it's a classic "Heads I win, tails you lose" system.

If you grew up here, like Percy Grainger, the music you wrote in Britain and America is still counted as Australian. Yet if you came here as an adult and you write music here, like Felix Werder, that's Australian music, too!

Back, though, to our brickbats. My short talks are mainly about the people who have given their names to something. Maybe a unit, like the ohm, the curie or the tesla, or a machine like Atwood's or Wimshurst's, or it could even be Bunsen's burner, Compton's Effect, Avogadro's hypothesis, or some other scientific item. Regrettably, very few of the people who gave their names to things are definably Australian. Local science content wasn't meant to be easy.

Perhaps the Braggs would fit. One of whom was born here, while the other worked here for some years, but that's about all. To get scientists of local interest, I need to look, as I have done and will continue to do, at foreign scientists who have some vague connection with us. Like the people who visited Australia at some time, such as Joseph Dana the mineralogist, or Charles Darwin, or T. H. Huxley, who courted his future wife in Sydney's Newtown.

I have a similar problem when it comes to women scientists. I believe in citing as many women scientists as I can, because this is a socially useful thing to do. While stupid people keep telling young girls that women can't be scientists, I want to counter that nonsense with as many suitable role models as I can muster.

Equally, we ought to tell colour-blind boys that they can do chemistry. After all, they're no worse off than John Dalton, who discovered the atom. And we should remind people that Australians can be world-class scientists, too. But you must be honest, and cite only the world-class examples. There's a limit to how far you can bend history, even for the most socially useful of reasons.

This aside, I'm a bit of a chauvinist, and I prefer to talk about Australians if I can. So I was rather upset by a critical letter to Robyn Williams, one which objected to a talk that I gave last year about Charles Wheatstone, an Englishman.

Briefly, Ken Slater said we'd got it wrong. Edward Davy, he wrote, was the true inventor of the telegraph. More importantly, Davy was a local lad who died in poverty in Australia, at Malmsbury in Victoria in 1885. I was guilty, he said, not only of getting it wrong, but I was doing an injustice to one of ours.

What I actually said was that Wheatstone is remembered these days for the Wheatstone bridge, which even Wheatstone said that he didn't invent, and that he is never credited with the concertina and the working telegraph, that he did invent.

All of my references agreed on Wheatstone as the inventor of the first working commercial telegraph, and I've even seen his machine on display in London, at the Science Museum. So I was not impressed by an unsubstantiated claim on behalf of somebody I'd never heard of. Davy doesn't even feature in the displays in the Powerhouse, so I was inclined to dismiss him as a nobody.

Still, I rounded up all the usual references and looked Davy up. I drew a series of blanks. Few of the overseas historical sources had heard of him, though I found a one-line dismissal of Davy as one of a number of inventors of "chemical telegraphs".

Chemical telegraphs are of some historical interest. They've been round in one form or another since the days of Alexander the Great, so I made a few notes about Edward Davy and filed them for future reference.

You may be surprised to hear me mention Alexander the Great in this context. It isn't a well-known story, so perhaps we might digress for a moment.

In those far-off days before pocket watches, Alexander's military successes owed much to his ability to coordinate the attacks of the wings of his army. He did this by having his generals each dip a piece of cloth in two different chemical solutions.

After a time that depended on the chemicals' concentrations, the cloth pieces would change colour, indicating the time to attack, and they would all fall upon the enemy at the same moment. This was, of course, the origin of the expression "Alexander's Rag-Time Band".

A number of early telegraphs used similar changes in chemically-treated cloth to record a message for later decoding. These chemical telegraphs, however, turned out to be a dead-end, and so I ignored the claim for Davy as the inventor of the telegraph. He had clearly never invented an electric telegraph, unlike Wheatstone.

Then the mail brought a long clipping from a journal called "Laboratory News", where Ken Slater's criticism was elaborated on by one Clive Coogan. I don't know him, but he knew about Davy.

The article gave me some basic details about Edward Davy, details that made me wonder if my historical sources were correct. Maybe Davy, like Phar Lap and Les Darcy, really was another colonial victim of the Overseas Conspiracy.

Clive Coogan referred to patents for electrical telegraphs. He even mentioned a few dates, and indicated that Davy had an entry to himself in the "Australian Dictionary of Biography".

This was more like it! I'm always ready to do justice to somebody I've wronged, and this was beginning to look like an interesting paper chase, so I got down to it.

The "Australian Dictionary of Biography" article was a disappointment, since most of it, the positive side of Edward Davy, had been repeated by Coogan's article. It seemed that Davy's claim to fame originated in a book by J. J. Fahie that was written in 1884, so I found a copy of the book and read it.

If you want to be pedantic, there were many different telegraphic inventors: Fahie lists dozens of them, even if you stay, as he does, only with the makers and proposers of electrical telegraphs.

You can go all the way back to 1729 and Stephen Gray, a little- known experimenter whose fame was deliberately and unfairly eclipsed by Newton. Gray may be little-known, but he's featured in the Powerhouse: I'll come back to him some other time.

Then there was "C.M." who outlined a plan for a telegraph in the Scots Magazine in 1753. This may have been a certain Charles Marshall, or it may have been a Charles Morrison, but even then, C. M. was a definite second to the Abbe Nollet.

In 1746, the Abbe had arranged a one-mile circumference circle of Carthusian monks, each pair of monks being linked by iron rods, and he then connected the two end monks to a Leyden jar, a primitive but effective capacitor or charge storage device. Nollet wanted to find out if the electric charge travelled instantaneously.

When the circuit was closed, the monks all shrieked and dropped their iron rods at the same time. This would have been all right, of course, as Carthusians don't take a vow of silence.

Clearly the Abbe's system would lead to a labour-intensive form of telegraph, but given a less than infinite number of monks, you could send the works of Shakespeare around the world.

A slow message perhaps, and one that might have trouble in crossing open water, but these were merely trivial details that could soon have been sorted out. I wonder if there's a Royal Society for the Prevention of Cruelty to Monks? Who cares, it was a dead end.

Over the rest of the 18th century, things fairly buzzed along. A Dr. Watson sent an electrical signal across the Thames in 1747, Joseph Bozolus suggested in 1767 that an alphabetic code could be worked out, Louis Odier suggested an electrical telegraph of five thousand leagues in 1773, and Volta proposed the use of his Volta pistol to send signals in 1777.

Chappe, inventor of the semaphore, experimented with an unusual electrical system in 1790. Imagine that you have two clockwork dials, each with a single hand that points in turn to the numerals 0 to 9. Provided these turn in unison, if I ring a bell when my dial points to 3, you can read a 3 off your dial as well.

Chappe, by the way, banged a casserole, a humble stewpan, rather than a bell. A pity, for if he had beaten about the bush instead, he would have invented the bush telegraph.

Chappe's saucepan method works well in a small room, but becomes rather useless at any great distance, as sound takes time to travel. By the time you hear my bell from 300 metres, a second has elapsed, and your dial probably says 4 or 5, not 3, as I intended.

Chappe turned to an electrical signal which Nollet proved took no measurable time to travel. This still had a singular drawback: the lack of suitable insulation for the wires, so in the end, Chappe turned to mechanical signalling systems and invented his semaphore.

The English knew of the French semaphore system, remains of which are still to be seen in Brittany. The English had their own system for sending naval signals, but this often failed to work due to fog, rain, or darkness. Even so, when Ralph Wedgwood, one of the famous potting family, proposed an electric telegraph to replace the semaphore, his timing was bad.

Wedgwood made his suggestion in 1814, just as peace broke out all over war-weary Europe. Lord Castlereagh at the Admiralty replied that the old system of shutter semaphores was enough, since the war was at an end, and money was scarce. Maybe if Napoleon had kept going for a bit longer in 1815, Wedgwood might have stood a chance, but as it was, no more came of his ideas.

In 1846, some years after Ralph Wedgwood's death, his son argued that the system had failed because there were no railroads in 1814: you needed the right-of-way along the rail line to establish a working telegraph, he said.

You needed a few other things as well, one of which was invented by Edward Davy, but Wedgwood might have been better advised to take out a patent on porcelain insulators.

That brings us to the work of Sir Francis Ronalds, as he later became. Chappe, you will recall, used revolving dials, and so did Ronalds, but with a few improvements. Ronalds' insulation was much better, as he proved by burying his wires a metre underground. Others talked about insulation, but Ronalds demonstrated that it could be achieved. The first vital requirement dropped into place.

Ronalds also allowed for the dials to be regularly synchronised with each other, and for a small explosion to be set off in one of Volta's gas pistols to warn that a message was about to be sent. His messages began with a bang -- I wonder if they ended in a whimper?

Alas, he also sent his proposal to the Admiralty. Mr. Barrow, Secretary of the Admiralty advised that "...telegraphs of any kind are now wholly unnecessary...". This was 1816, and Napoleon had been more permanently disposed of.

Up to now, all of the proposals had involved static electricity, but voltaic batteries had been presented to the world in 1800, and the interest in static electricity waned for the time being.

It was more fun you see, playing around with electricity from a battery. That sort of electricity kept on coming, where Leyden jars had to be recharged after every use. This was the second vital element in getting a working telegraph.

Benjamin Franklin had noticed, many years before, that even a static spark will eat away iron, and Joseph Priestley had wondered if an electric spark would change the colour of litmus. It did, and the path was now open for chemical recording telegraphs.

The most popular among the chemical methods was electrolysis. You need a separate wire, sometimes a pair of wires in the early days, for each letter to be signalled. Send the right message, and bubbles appear in a small electrolytic cell.

The trouble was, if you tried to send a message any distance, the voltage dropped, and you lost your signal. And that was where Edward Davy was to come up trumps with the other vital idea.

But before that could be, the dozen or more electrostatic telegraphs, all invented before Davy came on the scene, had to be set aside to make room for electromagnetic methods. Davy's is another story, one that I will come back to next week.

When I tell that story, you will see that, even if Davy deserves no credit as the inventor of the first telegraph, he certainly doesn't observe his present obscurity, for he was a first-rate inventor. First-rate, but dead unlucky.

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Last week, I explained how two "Science Show" listeners had drawn my attention to the case for Edward Davy, rather than Charles Wheatstone, as the inventor of the first electric telegraph. I then discussed the many people who sent electrical messages long before Davy came on the scene, but I stopped at the point where electricity and magnetism were combined to send a signal.

By 1820, Oersted had found that an electric current produced a magnetic field. That same year, Ampere proposed a telegraph that used this effect. He had a separate pair of wires and a separate needle for each letter. Crude, maybe, but better by far than strings of Carthusian monks, all linked by iron rods to a Leyden jar, the Abbe Nollet's model that I described last week.

Other famous names were coming onto the telegraphy scene as well: at Gottingen, Gauss and Weber laid wires over the rooftops for a couple of kilometres, and operated a successful telegraph from 1833 to 1838. Gauss and Weber beat both Wheatstone and Davy, but the distance they could transmit over was still limited, even with clever instrumentation to read weak signals.

By 1836, Steinheil had a telegraph, based on Gauss and Weber's, using two bell-tones, high and low, to carry a code similar in form to Morse code, on principles suggested by that mathematical genius, Gauss. Steinheil also had a method of recording the messages for later transcription, but this wasn't necessary. Two bells, differing by a sixth, were easy to distinguish, and so recording wasn't needed. This difference of a sixth was important, he said, for it was the most effective one for untrained ears.

Davy started his work about 1835, but his only patent was for a chemical system of recording signals and associated circuitry.

True, Davy demonstrated a working system in November and December 1837, but Wheatstone and Cooke had already sought a patent in May that year. The time has come, I think, to tell Davy's story.

Edward Davy was born in Devonshire, and may have been related to Humphrey Davy. He usually lends Humphrey a small amount of glory, for most chemists and geologists who use a "Davy blow-pipe" think it was Humphrey who invented it, not Edward, the surgeon turned inventor and chemist.

Here I must record the first of Edward's many disappointments in life. He intended to buy a medical practice in London, but instead bought the practice of a dispensing chemist. Still, he turned it to good account, what with his blow-pipe and his "Diamond Cement" for mending broken china and glass.

Then Edward started experimenting with a telegraph. His 1836 version used static electricity, and he recognised that six wires, plus a return wire, would be enough to send a signal. But this was the year that Steinheil was sending a binary code on a simple circuit by galvanic current. Edward wasn't in the race, not yet. He had too many wires, and the wrong form of electricity. Wheatstone and Cooke used six wires also, but they used real electric currents.

Soon after, though, we find him proposing a twenty-wire telegraph with ordinary batteries and tapping keys. A small compass needle, labelled with a letter of the alphabet, would be moved when a current travelled along its wire into a small coil.

The current travelling in the coil would produce a magnetic field that would deflect the needle, so that the letter marked on the needle came into view at the receiving end.

Then Davy had a bright idea: why not use current back and forth, so that each needle could reveal, say, an A on one end when the current went one way, and a B on the other end when the current went the other way?

It was about this point that Edward Davy had his important idea. Running currents around a mile of copper wire in Regent's Park in London, he was frustrated by the leakage of current into the ground.

A small current, he realised, was still enough to deflect a needle: what if that needle was part of a switch to send a fresh current surge into the next section of wire?

This was the origin of his electrical renewer, something that we now call the electrical relay. Davy was the first to think of it, he included it in his patent application, and that put him in the box seat. No other telegraph could operate without it, not if it were to operate over any distance, and Davy had the relay all tied up.

Now here begins the mystery, though I imagine that Davy's Australian descendants know the answer. The existing records give no reason for it, but late in 1838, he left London for Adelaide, never to return. In the careful neutral words of the Australian Dictionary of Biography", he was "...unaccompanied by his wife and child...".

Writing in 1883, an English nephew of Edward's, knowing that Edward was still alive in the colonies, said with firm Victorian reserve that, "Into the reasons of his leaving there is no occasion to enter. Suffice it to say that he had been contemplating doing so all through the end of 1837 and 1838, and that his reasons were entirely of a private kind."

When he left London, Edward left his affairs in the hands of his father, a medical man, who had knew nothing of telegraphy. It appears that Davy senior was already disappointed with his son, for Edward, remember, had not been practising as a surgeon.

The father had also contributed large amounts of money to the exercise, and could see no future in a system where Cooke and Wheatstone had sewn up the main (as he saw it) patents. As a medical man, he could have had no idea of the value of the electrical relay, although Cooke and Wheatstone certainly did.

In the end, Edward's father sold the whole patent to Cooke and Wheatstone for six hundred pounds, giving them access to the only element of Edward's patent that they wanted, the electrical relay.

But it would be unfair to blame the father alone: Edward had been too greedy. He had tried to interest businessmen in his invention, first offering 10%, and later 25%, so that those he dealt with lost interest in his proposals.

John Fahie, Davy's main champion in the late nineteenth century, believed that if Edward could only have found a partner, he would have succeeded equally with Cooke and Wheatstone as the introducer of a successful telegraph: all that was needed, he said, was some capital and some licking into shape.

And what of Edward in Australia: why didn't he pursue his invention, or at least seek the credit due for it? For one thing, he was far from the centre of things, and had left Cooke and Wheatstone in command of the field, his father had sold the key patent, and he had a number of other fish to fry.

The careful listener may have noticed that I mentioned him leaving his wife and son behind while at the same time referring to his Australian descendants.

I also mentioned his many disappointments in life, but I gave no details then, either of what I could glean of his family life, or what I had learned about his later life and career. I will outline them now, for not only are they interesting, they may offer some clues about his comparative lack of public front in his native land.

Edward did not at first practise as a surgeon in the colonies, but seems to have become a sort of land dealer in Adelaide, where ther were apparently some fifteen land transactions in his name.

Then he was elected to the Council, was briefly the editor of the Adelaide Examiner, and practised medicine for a while. Somewhere along the way, he remarried, although just what he and his first wife, Mary, did about a divorce, I cannot discover.

A librarian acquaintance who knows about such things tells me that in some cases, travelling to the Antipodes constituted a de facto divorce, so I thought it unlikely that he was hiding from Mary. His Australian life was a little too public, but it was a long way from home. Maybe he thought he was safe, who can say? I do know for certain that he was in regular correspondence with his own family in Britain, and they knew where he was.

In 1849, Davy took out a patent for a copper smelting process, and set up in business to operate this process, but the business failed, due to lack of capital. We next hear of him in Melbourne, where he was the assay master for a year on the princely salary for those days of fifteen hundred pounds.

A year later, there was a new Governor in Victoria, and Hotham set him adrift. After an indifferent period of farming near Malmsbury, Edward turned again to medicine, and seems to have stayed with that thereafter. He invented no more.

Just as well, probably, for his second wife bore him a large family before dying in 1877, and he presumably needed a secure income. There was a third wife, as well.

He might have remained in the colonies, unrecognised for his work on telegraphy, had John Fahie not tracked him down in 1883. The only other description of Davy's telegraph was meagre and misleading, and the apparatus was destroyed in 1880, and Davy's papers were probably about to go the same way when Fahie contacted a nephew in England. This saved the one reliable source of information on Davy's work.

In a five hundred page History of Electric Telegraphy to the Year 1837, published in 1884, John Fahie devotes more than a hundred pages to Davy, as well as a large appendix.

On top of this, Fahie published his views in an English journal, The Electrician, and so they became known to the Royal Society of Victoria. The President acclaimed Davy as "...the almost forgotten pioneer and inventor of the electric telegraph...", and proposed him for life honorary membership of the Society.

In the end, a sub-committee was formed to look into the best way of recognising Davy's contribution. Their sober recommendation appears to have been to recognise him only as "...the first to form a distinct conception of the relay system...". Whether he got his fully-deserved honorary life membership, I know not.

I started by questioning whether Davy could be correctly be called an Australian inventor. Perhaps his copper smelting patent could be listed as an Australian invention, and I have no doubt that his relay was an important invention, but what of his telegraph?

Not really a novel invention, I think. Not if you want to measure it up against some of the Germans and their developments. It undoubtedly had potential, but so did any number of others. Remember, obtaining a patent doesn't mean something is going to work: it just says that you are the first one to propose that idea.

Clive Coogan says that 1988 is the 150th anniversary of Davy's invention, and that we ought to honour him. Next July 4th is indeed the 150th anniversary of his patent, but let's remember Edward Davy for his real worth in inventing the relay.

If you really must celebrate a multiple of fifty years in telegraphy this year, then April 15th is the day when you should have celebrated. On that day, in 1738, M. Desaguliers sent an electrostatic signal through a straight string, 420 feet long, in the house of the Prince of Wales, confirming what Stephen Gray had observed a decade earlier.

For my part, I plan to remember Davy in future as the highly successful English inventor of the Davy blow-pipe. Now that, unlike most of his other ventures, was a success for him.

And the moral to this story? Well it's all a bit like the Russians and the Americans, both claiming some invention for one of their natives. The history taught in different countries has different heroes for the same action, and sometimes even has different outcomes, but I didn't realise that Australia has become divided.

The only two people who have corrected me, saying, in nice terms, that any fool knows that Edward Davy invented the telegraph are both Victorians. Until recently, I had never heard of Lores Bonney, either, though I have recently had the pleasure of three hours of her company. She's 91 now, but still as sharp as a tack.

Lores Who?, people are asking themselves right now, most of the way around Australia, but not in Queensland. Our least famous pioneer aviator lives in Queensland, and I'll bet she's better known up there.

Is it drawing too long a bow to suggest that, as our local heroes diverge, so too do our cultures? It may well be, but we don't have all that many high achievers: we ought to share them around, whether they be record-making aviators like Mrs. Bonney, or creative inventors like Edward Davy. I'm glad that two Victorians chose to throw gentle brickbats. Thanks, Ken, thanks, Clive.

Lores Bonney is dead now. I had the pleasure, in the late 1980s of wheeling her around the Powerhouse Museum, where she was then the feature of a display -- she was a bit frail, and I persuaded her that she would see more if she allowed me to wheel her, and we had a marvellous chat, which gave me a great deal that I think is missing from the history books. One of these days, I must get out my notes and do something with them.

This is one of a set of talks which were originally heard on ABC Radio National in Australia. All of the talks are copyright © Peter Macinnis, 2001, but permission will be readily granted on request for educational and most non-profit purposes. Contact Peter Macinnis specifying the talk(s) you want, and the purpose to which they will be put. For the rest of the talks, go to Six Months of Sundays.