Did the Radio Telegraph lead to a Miscarriage of Justice?

Posted on July 7, 2012 by Andrew

In an earlier blog, we learned how Cooke and Wheatstone’s telegraph played a central role in the capture of the murderer John Tawell as he travelled by train from Slough to London. In an analogous case, the murderer Dr Hawley Crippen became the first criminal to be caught using Marconi’s new radio telegraph.

Dr Hawley Crippen

 

 

 

 

 

 

 

 

 

 

 

Crippen and his mistress Ethel “Le Neve” Neave were identified as they sailed across the Atlantic in July 1910. The captain of the SS Montrose, Henry Kendall, became suspicious of the couple, and telegraphed the following message to his office in London using the Marconi radio system:

“Have strong suspicions that Crippen – London cellar murderer and accomplice – are amongst saloon passengers. Moustache taken off. Growing beard. Accomplice dressed as boy. Voice manner and build undoubtedly a girl. Travelling as Mr and Master Robinson.”

As a result of this message, Inspector Dew of Scotland Yard boarded the White Star liner Laurentic, and managed to arrive at the St Lawrence riverbefore the SS Montrose. Disguised as a tug boat pilot, he boarded the Montrose and arrested Crippen. Crippen was hanged at Pentonville Prison on 28th November 1910.

Crippen has acquired a particularly ghoulish reputation in the public mind, and a waxwork of him has been exhibited for many years in the Chamber of Horrors at Madame Tussaud’s in London. However, a century after the crime was committed, DNA analysis now suggests that the mutilated body found in the cellar was not that of Crippen’s wife, Cora, as was alleged at the trial. Indeed, it even suggests that the body was that of a man. Whether this proves that Crippen was innocent is debateable, but there is now a campaign to clear his name.

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The Strange Story of Phone Phreaking

Posted on May 20, 2012 by Andrew

During the 1960’s, the use of analogue signalling tones between telephone exchanges gave rise to a new phenomenon called “Phone Phreaking”. The word “phreak” is apparently a combination of “phone”, “free” and “freak”, so it’s rather a good name.

Phone phreaking seems to have developed independently in a number of different places, but one of the early pioneers was a blind American schoolboy named Joe Engressia. At the age of eight, it is said that Engressia liked to dial non-working telephone numbers just to listen to the recording that said “This number is not in service”. One day, he started whistling a tune while listening to a recorded announcement and was surprised to find that the line suddenly went dead. When he repeated the experiment, the result was the same. Full of curiosity, he rang the local phone company and asked them why this had happened. An engineer explained that the phenomenon was known as “talk-off”, and that it occurred when a 2,600Hz tone occurred by chance during the course of a telephone conversation.

Joe subsequently discovered that he could use this knowledge to obtain free telephone calls. In 1969, while a student at the University of South Florida, he was disciplined by the college after being caught whistling-up free long distance calls for fellow students. His exploits eventually led to him being arrested and prosecuted for “malicious mischief” after he featured prominently in a famous 1971 article on phone phreaking in Esquire magazine.

Joe Engressia had perfect pitch, which meant that he could whistle an accurate 2,600 Hz tone whenever he wanted. However, for the benefit of lesser mortals without perfect pitch (or those who could not whistle), electronic “blue box” tone generators soon started to appear. These boxes were held next to the telephone mouthpiece, and enabled phone phreaks to generate the full range of signalling tones that they needed. It was even discovered that the plastic whistle included as a free gift in packets of Cap’n Crunch breakfast cereal would produce the required 2,600 Hz tone.

Cap'n Crunch Whistle

Cap'n Crunch Whistle

Phone phreaks loved to demonstrate their expertise by setting up complex calls with devious routes. For example, a call might be established between two adjacent telephones with a route that threaded its way around the world, thereby enabling the speaker to listen to the sound of their own voice. Telephone conference calls were organised – free, of course – during which phreaks would exchange information about the inner workings of the telephone system and brag about their latest exploits. Since these activities were illegal, calls of this type were often made from public phone boxes, but the fear of prosecution seems to have done little to deter dedicated phone phreaks. It was only with the introduction of digital telephone exchanges in the 1980’s that phone phreaking finally came to an end.

Photograph courtesy of Keith Schneider, Gasoline Alley Antiques, http://www.gasolinealleyantiques.com
 
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Treating a Paranoid Computer

Posted on April 10, 2012 by Andrew

The ARPANET was an early computer network that played a critical role in the development of the Internet. In 1972, Robert Kahn organized the first public demonstration of the ARPANET’s capabilities at the International Conference on Computer Communications in Washington, DC. This included “conversations” across the United States between a computer at MIT that was programmed to behave like a psychiatrist, and a computer at Stanford that mimicked the behaviour of a paranoid psychotic. One of their conversations went as follows:

Doctor:    “Good evening. Tell me your problems.”
Patient:   “People get on my nerves sometimes.”
Doctor:    “I am not sure I understand you.”
Patient:   “You should pay more attention.”
Doctor:    “Suppose you should pay more attention.”
Patient:   “You’re entitled to your own opinion.”
Doctor:    “What makes you think I am entitled to my own opinion?”
Patient:   “It bothers me just to be around people in general.”

These demonstrations of long-distance networking may not have done much to advance the treatment of paranoid psychosis, but they brought the ARPANET’s capabilities to a much wider audience. They also helped to silence the doubters who had claimed that the newfangled packet switching technology would never work.

(Conversation quoted from “Where Wizards Stay Up Late – the Origins of the Internet”, Katie Hafner & Matthew Lyon, Touchstone, 1998)

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If At First You Don’t Succeed . . .

Posted on March 20, 2012 by Andrew

The successful laying of a trans-Atlantic cable was one of the most extraordinary feats of engineering in the history of telecoms. The hero of our story is Cyrus Field, an American businessman who had made his fortune in the New York textile and paper trade. At a time at which existing submarine cables rarely exceeded 100 miles in length, Field was planning a submarine cable 2,000 miles long laid between Ireland and Newfoundland, with an additional 1,000 miles of cable to link Newfoundland with New York City.

Cyrus Field

Field joined up with four other New York businessmen to form the grandly named New York, Newfoundland and London Telegraph Company. They decided to start with the “easy” part of the project—the link between Newfoundland and New York City. Although this was mainly an overland route, the difficult terrain and the appalling weather presented considerable difficulties. Furthermore, the first attempt to lay an 85-mile submarine cable across the Cabot Strait was a complete disaster and they had to return for a second (successful) attempt the following year. The Newfoundland to New York City link was finally completed in 1856.

At this point, the company had exhausted its funds, so Field turned to England for additional investment. In October 1856, he created the Atlantic Telegraph Company and started selling stock in London. One of Field’s great strengths was a complete inability to accept defeat. The following list of his attempts to lay a trans-Atlantic cable stands as testimony to his extraordinary persistence:

Attempt No. 1

In 1857, USS Niagara and HMS Agamemnon were each loaded with 1,250 miles of cable and they set sail from Southern Ireland. The plan was that the Niagara would lay its half of the cable first and the Agamemnon would then take over when they reached mid-Atlantic. However, the cable broke after only 440 miles had been laid.

Attempt No. 2

For the second attempt, it was agreed that the Niagara and Agamemnon would both start laying cable in mid-Atlantic and would proceed in opposite directions. However, on their way to the starting point, the ships encountered a massive storm that lasted for 6 days and threatened to capsize both vessels. Despite 45 crew members requiring treatment for injuries, they did eventually manage to start laying cable but it snapped almost immediately. They started again, and this time they managed to lay 80 miles of cable before it snapped. On the third try, the cable snapped after 220 miles had been laid.

Attempt No. 3

On July 28, 1858, Niagara and Agamemnon set sail once again and this time they managed to complete the installation of the cable. However, attempts to communicate over the installed cable were less successful—it was found that the received signal was so weak that over half the words needed to be repeated. In an attempt to rectify the problem, the company’s Chief Engineer increased the voltage. To his consternation, this burnt out the cable’s insulation and rendered it useless. The public rejoicing that had followed the first successful laying of a trans-Atlantic cable was brought to an abrupt and acrimonious end.

Attempt No. 4

After this string of failures, it was decided that the next attempt would have to use a cable that was almost three times heavier. This raised the question of how many ships would be needed to install such a massive cable. The problem came to the attention of the famous engineer, Isambard Kingdom Brunel, who invited Cyrus Field to visit the construction site of the Great Eastern. At 693 feet long, this ship was five times the size of any other vessel afloat when it was completed in 1858, and it was capable of carrying the full length of cable needed to span the Atlantic. However, the first attempt using the Great Eastern met with failure when the cable broke just 600 miles short of the Newfoundland coast. Interestingly, the sudden loss of connectivity in the cable was detected back in Ireland, leading to speculation that the Great Eastern had sunk; there was considerable relief when it eventually returned to port.

Attempt No. 5

In July 1866, the Great Eastern left Ireland for another attempt and Field’s persistence finally paid off—after just 2 weeks, the cable had been successfully installed. Telegraph messages were soon being exchanged across the Atlantic and the link was opened up for commercial traffic. Amazingly, this cable was still in use 100 years later.

Later that summer, the cable that had broken during Attempt No. 4 was successfully repaired and the remaining 600 miles of cable were laid. Within a month of the first trans-Atlantic cable becoming operational, a second cable was also transmitting messages.

It is satisfying to note that this tale of dogged determination had a happy ending. The long sequence of failures caused widespread scepticism about the project, and many investors decided to cut their losses before success was achieved. Western Union, the dominant telegraph operator in the United States, were so convinced that a trans-Atlantic cable would never work that they started building a telegraph link to Europe via Siberia—a route that required only 25 miles of submarine cable to cross the Bering Straits. These plans had to be scrapped when they heard of Field’s success.

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Are Radio Waves Bad for Your Health?

Posted on February 4, 2012 by Andrew

The health risks associated with radioactivity have been recognized for many years. Alpha, beta and gamma emissions from radioactive sources can ionize atoms or molecules that they encounter by detaching electrons from them. People exposed to high levels of ionizing radiation can develop a number of health problems, including radiation sickness, sterility, cancer and genetic damage. Since gamma rays are a form of electromagnetic radiation, it is not surprising that concerns should also be raised about electromagnetic radiation at other frequencies.  X-rays and ultraviolet are examples of ionizing radiation from other parts of the electromagnetic spectrum, and even visible light can be ionizing under some circumstances. However, electromagnetic radiation at lower frequencies does not have the energy to cause ionization, and microwaves and radio waves are both examples of non-ionizing radiation. In other words, people living near a radio transmitter are NOT being bombarded with ionizing radiation.

In spite of this, concerns have been expressed about potentially harmful effects caused by cell phones, cellular base stations, WiFi networks, microwave transmission links and satellite ground stations. Although these systems transmit at frequencies that cannot break atomic bonds, they can cause heating of the skin in much the same way as a microwave oven. To address this problem, the maximum output power has been restricted to levels at which the heating effect is far too small to cause cell damage. 

Mobile Base Station

Mobile Base Station

However, concerns continue to be expressed about non-thermal mechanisms that might cause a risk to health. A study published in April 2008 found that exposure to mobile phone signals for just 5 minutes could stimulate human cells to divide; this process occurs naturally when tissue grows or rejuvenates, but it is also a key part in the development of cancer. It has also been suggested that a small percentage of the population suffers from “EMF sensitivity” and that this accounts for a wide range of problems, including headaches, tinnitus, nausea and stomach upsets.

Despite the lack of clear scientific evidence that using a mobile phone is a health hazard, it is reasonable to assume that holding a radio transmitter against the side of the head for long periods of time cannot be good for you. Powerful campaigns have been fought to prevent the construction of mobile base stations near homes and schools after research suggested that children’s brains absorb 50–70% more radiation from mobile handsets than adults because their skulls are smaller. Using similar arguments, WiFi networks in schools have been blamed for problems ranging from poor concentration in the classroom to Attention Deficit Hyperactivity Disorder (ADHD).

Such claims are easy to make and hard to refute. Poor concentration in the classroom could be blamed on a nearby WiFi network, but a diet of junk food combined with lack of exercise and late nights spent playing video games is a more likely explanation. People fall ill for all kinds of reasons, and the fact that they used their mobile phone immediately before the first symptoms appeared does not prove cause and effect. In fact, epidemiological studies have so far failed to provide any convincing evidence that using WiFi networks or mobile phones leads to health problems. 

However, we know that the health problems caused by exposure to ionizing radiation from a nuclear explosion may not appear until many years after the event, so it is possible that problems caused by using mobile phones or WiFi networks will not appear for a while yet. We need to remain vigilant until the evidence is completely clear. The probability of a long-term health risk is extremely small, but if such a risk were to be established, the impact could be devastating.

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Who REALLY Invented the Telephone?

Posted on January 28, 2012 by Andrew

As any quiz enthusiast will tell you, Alexander Graham Bell invented the telephone. He was awarded a patent for the telephone in 1876, and he and his fledgling telephone company successfully defended that patent against more than 600 legal challenges – five of which went all the way to the US Supreme Court. This, you might think, is pretty good evidence that Bell really did get there first.

The telephone patent subsequently turned out to be one of the most valuable in history, and that may help to explain some of the enthusiasm with which it was challenged in the courts. However, there have always been lingering suspicions that Bell’s success may have been partly attributable to dodgy dealings within the US Patent Office. Careful study of Bell’s laboratory notebook throws up some remarkable similarities to the patent caveat filed by his arch rival, Elisha Gray. It appears that Bell may have retrospectively modified the text of his patent application after being shown Elisha Gray’s caveat by an accomplice who worked in the patent office.

I was aware of this controversy when I wrote about the invention of the telephone in DOT-DASH TO DOT.COM, but my treatment of the subject focussed on the sequence of events that led Bell from his investigations into a “harmonic telegraph” to the development of the “gallows telephone”, and these facts are not in dispute.  Bell’s gallows telephone was based on sound principles and ought to have worked – but didn’t because of an implementation error. At that point, Bell suddenly (and inexplicably) changed to a totally different “variable resistance” microphone that looked strangely similar to one used by Gray, and this produced a working telephone. As I said in the book:

“Careful examination of Gray’s caveat shows that he understood the principles of the telephone and—given a little more time—would almost certainly have been able to produce a working model. Furthermore, Gray’s caveat contained a description of a variable resistance transmitter that was remarkably similar to the one used by Bell when he spoke the first words to be received over a telephone. It was later claimed that the part of Bell’s patent that deals with the variable resistance transmitter was added after it had been filed. Gray believed that Bell had updated his patent application after illegally being shown a copy of Gray’s caveat by friends in the Patent Office.” 

I’ve just finished reading “The Telephone Gambit” by Seth Shulman, and I have to say that I’m now pretty convinced that Bell won the race by cheating. I still believe that Bell arrived at all the key components of a viable telephone through his own efforts, but I’m less certain that he would have been awarded the famous patent without some help from within the US Patent Office. The Telephone Gambit reads like a detective story, and I strongly recommend it to anyone interested in this fascinating corner of history.

So does this mean that future quizzes will recognise Elisha Gray as the inventor of the telephone? Well, possibly not. In 2002, the US House of Representatives passed a resolution that named a Florentine immigrant to the United States, Antonio Meucci, as the inventor of the telephone (strangely, Shulman’s book doesn’t mention him at all). Furthermore, there are some who would argue that a German schoolteacher called Philipp Reis actually got there first. This is a question that doesn’t have a simple answer, and my advice would be to omit it from future quizzes!

Alexander Graham Bell, Elisha Gray and Antonio Meucci

Alexander Graham Bell, Elisha Gray and Antonio Meucci

 

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This Is All Getting A Bit Scary

Posted on January 17, 2012 by Andrew

Since the attack on the World Trade Center on September 11, 2001, there has been considerable speculation about the possibility of cyber terrorism. In March 2000, a disgruntled Australian employee used the internet to release one million litres of raw sewage into the rivers and coastal waters of Queensland. Could terrorists use the internet to gain control of a nuclear power station, an air traffic control system or a military installation? The possibilities for causing mayhem in this way are limited only by the imagination, and the fact that it hasn’t happened yet does not prove that it can’t be done. Hackers have demonstrated convincingly that it is possible to penetrate highly sensitive government and military computers using nothing more sophisticated than a laptop computer and a connection to the internet. Is it only a matter of time before the West is held to ransom by terrorists operating from somewhere beyond the reach of legal or military sanctions?

Experts dismiss these suggestions by pointing out that critical systems are “air gapped” from external networks (i.e. there is no physical connection at all). But the Stuxnet worm managed to infect the Iranian nuclear enrichment program in spite of the presence of an air gap. And there are plenty of systems out there that are supposed to be air gapped – but actually aren’t. During testing of the Boeing 787 Dreamliner, it was found that no air gap existed between the aircraft’s control systems and the network used to provide passengers with in-flight internet access. If this vulnerability hadn’t been found during a routine FAA inspection, it might have enabled a passenger with advanced hacking skills to have a go at flying the plane.

Boeing 787 Dreamliner - with air gap added!

Boeing 787 Dreamliner - with air gap added!

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Let’s Hear It for the Bad Boys of Physics!

Posted on January 8, 2012 by Andrew

Surprising as it may seem, there are still some major barriers that are holding back the march of telecommunications. One of these barriers is Einstein’s universal speed limit – the speed of light – which applies to electrical currents in copper wire, beams of light in fibre optic cables and microwave communications with satellites. Light travels at approximately 200,000 km/sec in glass and at nearly 300,000 km/sec in air, but this is still far too slow for some telecoms applications. Fibre optic links can generate long enough delays to cause time-outs on high-speed data applications, and the quarter-second delay introduced by satellites is something that we see every day on our television screens when journalists are reporting from remote locations. Communications with probes in the outer reaches of the solar system are plagued by round-trip delays of up to a day, and there is simply no prospect of holding a telephone conversation with any extra-terrestrial civilization that may be orbiting a distant star.

Unless our current understanding of relativity theory turns out to be incorrect, the speed of light is one restriction that we are just going to have to live with. But recent developments at the Gran Sasso laboratory in Italy have raised the tantalising possibility that neutrinos may be capable of travelling faster than the speed of light. Admittedly, it’s only 0.0025% faster than light, but even that would be enough to prove that this fundamental speed limit can be breached. Another possibility is that Einstein’s speed limit is still valid, but the neutrinos have found a short cut through an additional dimension that we are not currently aware of. Either way, if these results prove to be correct, then faster communication may perhaps be a realistic aspiration.

Neutrinos have been described as the “bad boys of physics” by Professor Joao Magueijo of Imperial College, London. If any sub-atomic particles were going to be caught speeding, it was always likely to be neutrinos. However, these particles are so small that they very rarely interact with other particles, which makes them very difficult to work with. The experiments at Gran Sasso were conducted with extreme care, but there is still a high probability that the results will eventually be attributed to experimental error. However, if they do prove to be correct, and if travelling faster than light does not entail travelling backwards in time, then the race would be on to see how this new understanding of the physical world could be applied in the world of telecommunications.

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A New Year Murder

Posted on January 1, 2012 by Andrew

In 1839, William Fothergill Cooke and Charles Wheatstone opened the world’s first public telegraph service on a 13-mile stretch of rail track between London Paddington and West Drayton. The telegraph received some sensational publicity a few years later when it played a crucial role in the capture of a murderer.

On New Year’s Day in 1845, John Tawell travelled to Slough with the intention of poisoning his mistress. It appears that he had expected her to die quietly, so he was greatly disconcerted when she let out a bloodcurdling scream. To make good his escape, he ran to the station where a train was just departing for London. As he climbed aboard and settled into his seat, he was firmly convinced that he would have disappeared into the London crowds long before news of his crime reached the city.

However, he had not reckoned on Cooke and Wheatstone’s telegraph. The following message was flashed up the line:

“A MURDER HAS JUST BEEN COMMITTED AT SALT HILL AND THE SUSPECTED MURDERER WAS SEEN TO TAKE A FIRST CLASS TICKET TO LONDON BY THE TRAIN WHICH LEFT SLOUGH AT 742PM  HE IS IN THE GARB OF A KWAKER WITH A GREAT COAT ON WHICH REACHES NEARLY DOWN TO HIS FEET  HE IS IN THE LAST COMPARTMENT OF THE SECOND CLASS COMPARTMENT.”

The word “KWAKER” caused some confusion at Paddington until it was realized that the intended word was “QUAKER”—this type of telegraph was not capable of transmitting the letters “Q” or “U”. When Tawell arrived in London, the police were waiting for him. He was subsequently found guilty of murder and hanged.

John Tawell

In an analogous case in July 1910, Marconi’s new radio telegraph played a crucial role in the capture of the murderer Dr Hawley Crippen and his mistress Ethel “Le Neve” Neave as they made their get-away across the Atlantic. The captain of the SS Montrose, Henry Kendall, became suspicious of a couple of his passengers, and he telegraphed the following message to London:

“HAVE STRONG SUSPICIONS THAT CRIPPEN—LONDON CELLAR MURDERER AND ACCOMPLICE—ARE AMONGST SALOON PASSENGERS. MOUSTACHE TAKEN OFF. GROWING BEARD. ACCOMPLICE DRESSED AS BOY. VOICE MANNER AND BUILD UNDOUBTEDLY A GIRL. TRAVELLING AS MR AND MASTER ROBINSON.”

As a result of this message, Inspector Dew of Scotland Yard boarded the White Star liner Laurentic and managed to arrive at the St Lawrence river before the SS Montrose. Disguised as a tug boat pilot, he boarded the Montrose and made the arrest. Crippen was hanged at Pentonville Prison on November 28, 1910. Recent DNA evidence has raised some concerns about this conviction.

Dr Hawley Crippen
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The First Wireless Telephone

Posted on December 28, 2011 by Andrew

On 3rd June 1880, Alexander Graham Bell transmitted the first wireless telephone message using his newly-invented “Photophone”.

Alexander Graham Bell's Photophone

The Photophone contained a flexible mirror that vibrated in response to the speaker’s voice. When sunlight was projected on to the mirror, the vibrations were superimposed upon the reflected beam. At the receiver, crystalline selenium cells were used to detect the light beam. The resistance of these cells decreased as the intensity of the light increased, thereby allowing the speech signal to modulate an electrical current. This current could then be converted back into audible speech using an ordinary telephone receiver. In effect, the Photophone was a telephone that used light instead of electricity to carry the signal from the transmitter to the receiver.

Bell took out four separate patents relating to the Photophone, and it is reported that he considered it to be a more important invention than the telephone because it could operate without wires. However, his design was vulnerable to interference from rain or fog, and it could only communicate over a restricted distance. It was not until the development of fibre optics that communication using a beam of light became a practical possibility.

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