Colossus: Bletchley Park's Greatest Secret

Colossus: Bletchley Park's Greatest Secret

by Paul Gannon

NOOK Book(eBook)

$10.99 $11.99 Save 8% Current price is $10.99, Original price is $11.99. You Save 8%.
View All Available Formats & Editions

Available on Compatible NOOK Devices and the free NOOK Apps.
WANT A NOOK?  Explore Now
LEND ME® See Details

Product Details

ISBN-13: 9781782394020
Publisher: Atlantic Books
Publication date: 01/01/2007
Sold by: Barnes & Noble
Format: NOOK Book
Pages: 240
Sales rank: 1,101,573
File size: 3 MB

About the Author

Paul Gannon writes on all aspects of information and communications technology.
Paul Gannon is a writer on all aspects of information and communications technology. He is the author of Trojan Horses & National Champions: A History of the European Computing and Telecommunications Industry (IT Book of the Year, 1997) and Colossus (Atlantic, 2006).

Read an Excerpt


Bletchley Park's Greatest Secret

By Paul Gannon

Grove Atlantic Ltd

Copyright © 2006 Paul Gannon
All rights reserved.
ISBN: 978-1-78239-402-0


Wireless War One

In August 1914, a few days after the start of the First World War, the assistant district commissioner of Fanning Island, one of the most remote outposts of the British Empire, donned his symbol of authority – a pith helmet – and walked down to the beach to welcome a French warship. The island had no harbour, not even a jetty, so the warship lowered a small boat, and a landing party rowed towards and then past the coral reef that constrained the approach of larger vessels. Some of the workers who collected copra on the island dashed out into the surf to meet the party: it was the practice for visitors to be carried ashore so that they need not wet their feet. But, as the workers waded out to the boat, a uniformed officer jumped from it, ran past the porters up to the beach and the waiting assistant district commissioner. He then pulled out a pistol, waved it around for all to see and, pointing it at the commissioner's stomach, announced, 'You are my prisoner.' Out beyond the coral reef, the French flag was lowered and a German one raised in its place: the warship was, in fact, the light cruiser Nuernberg.

Fanning Island, located at latitude 3 degrees, 51 minutes North, longitude 159 degrees, 21 minutes West, is sixty-five kilometres (forty miles) north of the Equator and 1,900 kilometres (1,200 miles) from Hawaii. It is a typically tiny spot on the map of the Pacific at fifteen kilometres long by six kilometres wide, and very low – largely just about a metre above sea level, rising to a maximum of just over three metres. A few dozen natives of other Pacific islands were employed there by a British company to collect copra, the dried kernel of the coconut from which coconut oil is extracted, and until the beginning of the twentieth century the island had been otherwise unoccupied. However, the purpose of the German ship's visit was not to seize a source of copra. Rather, it was to destroy a telegraph-cable relay station. For the island was the first landing stage of the British transpacific telegraph cable, laid in 1902, as it headed away from Canada towards Australia and New Zealand. A staff of ten to twelve people kept the cable open to telegraph traffic day and night, all year round. The remote island was a tough posting for telegraph staff where, at least until the arrival of the German ship, little tended to distinguish one day from another.

The Pacific cable was the latest link in the network of All-Red Routes, owned and operated by British companies, which encircled the globe and provided the communications that both bound together the British Empire and supported every other developed country's international trade and commerce. The 'All-Red' label derived from the colour used on British maps to show the territories of the Empire, a practice that would endure until the 1960s. The main cable routes in the network touched land only on the territories of the Empire. Where there was no British territory, land was annexed – as had happened with the remote Fanning Island, no nation having previously seen the copra as being worth the effort of claiming the island, or discerning any strategic or tactical value in its possession. But the coming of the cable made it a significant location, there being no other suitable British possession in the mid-Pacific. The distance from Fanning Island to the western coast of Canada still required a single cable span of 5,600 kilometres (3,500 miles), then 'very much longer than any in existence'. The next link, between Fanning Island and Fuji, was another 3,200 kilometres (2,000 miles), while the entire cable length was 11,900 kilometres (7,400 miles). Indeed, it was with the completion of the Pacific cable that the Imperial Defence Committee was able to report to the British government, 'The dependence of the United Kingdom on cable stations situated upon foreign territory has been generally eliminated.'

At the end of the nineteenth century, Britain dominated the international cable networks. No other country possessed such an extensive network. One company, the Eastern Telegraph Company, controlled almost 50 per cent of the world's submarine cables, while other British companies owned another 30 per cent of the cable routes. These figures underestimate the extent of British domination of worldwide telegraph traffic, because, apart from a number of transatlantic cables, most of the submarine cables owned by non-British companies were local links, connecting to British long-distance routes. For a while, writes Daniel Headrick, historian of the politics of telecommunications, this British domination of cable networks 'aroused the admiration and envy of foreigners, but little hostility. In an age of free trade, nations tolerated each other's comparative advantages. As long as the European powers were preoccupied with Continental problems and the United States with its own westward expansion, the seas were Britain's special sphere ... The benefit of the telegraph for colonial administration, news and world trade were so evident that the ownership of the cables was seen as a minor issue.' In this spirit, in 1885, the Committee for Colonial Defence (later renamed the Imperial Defence Committee) had declared that submarine cables should be treated as neutral assets that would not be interfered with during a conflict.

These laissez-faire attitudes were to disappear as the nineteenth century drew to an end. Conflict between European nations, for example, in the rush to acquire colonies made foreign governments and their traders more resentful of British control. Several incidents – such as that at Fashoda in 1898 when British and French colonial forces came close to clashing in the Sudan – demonstrated that the British were quite happy to make use of their dominance to read the telegrams of other countries and to use the information thus gleaned for political, military or commercial advantage. (Non-British telegrams were given lower priority than British ones and could be delayed as well as read.) This growing resentment of British control clearly signalled that the cable network would be at risk in the event of war, and so the Imperial Defence Committee turned its attention to how the cables could be protected. Its policy of treating cables as neutral assets shifted towards one of attacking other countries' cables, regardless of whether they were owned by enemies or neutrals.

According to practice, which, in the absence of any provision dealing specifically with cable-cutting, must be regarded as the international law on the subject, it is open to a belligerent to cut cables connecting a point on the territory of the belligerent and a point on the territory of a neutral, as well as those connecting points on belligerent territory ... It may be expected that an enemy such as Germany will cut as many as possible of the cables serving British interests, whether they connect points on neutral territory or not ... In these circumstances, and seeing that there are places which it would be desirable for naval and military reasons to cut off from telegraphic communication in the war with Germany, or with Germany and her allies, the [Committee] are of opinion that the right to cut cables, whether neutral connecting points or not, should be exercised whenever the exigencies of war demand it ... Generally speaking, if France and Russia were in alliance with this country, it would be possible to isolate Germany from practically the whole world, outside Europe, by cutting the cables to the Azores, Tenerife, and Vigo and the three cables on Yap Island.

The policy of communications neutrality had in effect been replaced by the use of cables and communications as a weapon of war. Other states, including Germany and the United States, were to take the same view. And it was for this reason that, in August 1914, out in the mid-Pacific, two German ships, the Nuernburg and the Titania, headed for Fanning Island, planning to use deception and the French flag to gain a bloodless landing on the island. The German officer explained that his orders were to destroy the cable station and that, if no one got in his way, no one would be hurt. The German seamen used hand grenades to blow up the powerhouse and then they smashed equipment in the operating room, spilling battery acid all over the floor. But the acid prevented them from continuing their destructive spree in an adjoining room that held sensitive equipment allowing the cable to work in both directions simultaneously. It would have taken some months to get this equipment set up again if it had been damaged, but, ironically, the careless spilling of the acid saved it.

Meanwhile, out at sea the cable itself was under attack. The Titania, which carried cable-cutting gear, had already hacked through the windward cable in several places and dragged the end out to deep water. The Nuernburg started fishing up the other cable link. But this operation was also botched. The light cruiser lacked specialist grappling equipment and so the cable had to be raised in shallow water: although it was cut, its severed ends could nonetheless be recovered fairly easily. Had the long cable end been dragged out over the edge of the reef, it could only have been lifted by a cable-repair ship. As it was, no sooner had the Germans left than the cable was recovered by staff from the plantation using a rowing boat and a grappling hook fashioned out of a pickaxe. Engineers patched up a temporary connection and informed the next relay station at Suva, Fiji, of what had happened. Suva passed the message on, just in time, for it was the next port of call for the Titania and the Nuernburg and suffered similar damage. However, a cable-repair ship was dispatched from Auckland with the equipment needed to get both relay stations back into operation. It took several weeks to repair the damage, but neither relay station was attacked again and both provided normal service for the duration of the war.

The only other attempt to disrupt British strategic communications was an attack on another relay station in South West Africa where the staff were held as prisoners for a year. But the loss of the relay station did not matter. Britain had long before laid down second 'parallel' routes in its All-Red network, precisely to guarantee that communications would not be disrupted by the loss of a link or two. British maritime supremacy over the German surface fleet secured Britain's network and chased the raiders from the seas. (The Nuernberg herself was sunk near the Falklands Islands a few months later, along with all but one of German Admiral Graf von Spee's squadron.) Britain's cable network could now become a fully fledged weapon of war.

Even before the two German ships had approached Fanning Island, Germany itself had already been effectively isolated. Its cables were cut not haphazardly, or just at one or two remote points, but systematically and permanently. Britain, with its open economy, needed its global network to harness the resources of its Empire for the war. Constraining Germany's cable communications would undermine German efforts to win support in the USA and Latin America, as well as the Middle East and Asia, by closing down and controlling the channels that allowed Germany to gather intelligence and disseminate propaganda. The British cable ship Telconia executed one of Britain's first military actions of the war when it cut the five cables that linked Germany to the Americas and elsewhere. Shortly afterwards, Russia severed land cables that enabled Austria and Germany to communicate with the Middle East. Then Britain turned on Germany's overseas wireless stations, destroying those at Dar-es-Salaam and Yap in the Caroline Islands; others were destroyed in the Pacific or taken over by the Japanese, then Britain's allies. It took time to close the last loopholes, but eventually Germany was cut off from cable communication with the outside world for the remainder of the war. And the only links that remained open – courtesy of neutral governments which allowed German coded messages to be bundled in with their own diplomatic traffic – were closely monitored by the British as, at some point in their journey, they went over a British cable. This stranglehold on German international communications eventually had a decisive effect on the outcome of the war.

At the end of July 1914, a group of wireless engineers from the British Marconi Company visited their counterparts and competitors at the Telefunken Company, and were shown around its factories and research laboratory near Berlin. The most impressive demonstration was saved for the last day when the British engineers were taken to the new high-power wireless station at Nauen some fifteen kilometres from the German capital. Nauen was the most powerful wireless station in the world and an equally powerful statement of Germany's ambitions to neutralize the stranglehold exercised by Britain on cable communications. The British team saw the massive new antennas and the 200 kW high-frequency alternators that powered the transmitter. The trip had been the initiative of Telefunken and the German government, for such wireless technology promised to break the British cable monopoly and Germany wanted Britain to know it. According to the Marconi Company's official history, 'Immediately [the British] left the station, Nauen closed down its normal commercial operations and the military, who had been awaiting the visitors' departure, took over control.' Later, on 31 August 1914, Nauen sent out a message, on behalf of the Imperial Admiralty, for re -transmission by the chain of German wireless stations to 'all ships and wireless stations'. Germany, it said, was 'threatened with danger of war. Enter no English, French or Russian harbours'.

Germany, realizing that it lagged behind Britain in the control of cable communications, had eagerly embraced the idea of wireless. The new technology promised that Germany no longer had to endure the British intercepting, delaying and, worst of all, reading its messages. Unlike cables, which run from point to point, wireless can communicate with any number of points within its transmission range. It is quicker and easier to set up, and soon it was able to cover great distances. Wireless, an electrical technology, was an area in which German companies were expected to excel. In the latter half of the nineteenth century, the rapid advance of the German telephone and electrical industry, a key sector in the second industrial revolution, challenged British supremacy in telecommunications. The new wave of industrial and technological innovations demanded a much closer link between science and technology than in the industries that Britain had pioneered, and it was in Germany that the first industrial research laboratories appeared, marking an important stage in the development of industrial production. As a relative newcomer to industrialization, Germany found it easier to adopt the more coherent approach now needed, while British companies were slower to change and adapt. 'Beyond question, the creation of this [electrical] industry was the greatest single achievement of modern Germany,' wrote the economic historian J H Clapham. (In 1895, Germany employed 26,000 in its electrical industry; by 1906, the figure was 107,000. In 1913, Britain's electrical industry was about half the size of that of Germany.) The leading German electrical companies Siemens & Halske and AEG were encouraged to merge their wireless operations in the national interest, thereby creating Telefunken. By 1906, transatlantic wireless telegraphy was possible and Germany rapidly created a chain of international long-distance wireless stations, with Nauen at the centre of the web linking German possessions in Africa and the Pacific, along with one station in the United States. At a stroke, Germany was free of Britain's hard-won dominance of global communications.


Excerpted from Colossus by Paul Gannon. Copyright © 2006 Paul Gannon. Excerpted by permission of Grove Atlantic Ltd.
All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.
Excerpts are provided by Dial-A-Book Inc. solely for the personal use of visitors to this web site.

Table of Contents


A Word about Words,
1 Wireless War One,
2 Codes and Ciphers,
3 Between the Wars,
4 Wireless War Two,
5 A Window on a War,
6 NoMo,
7 'If the Wind Meets it',
8 Knockholt,
10 Fishing the Depths,
11 Herring and the Cat's Whiskers,
12 'Hier ist so traurig',
13 Making the Difference,
14 The Robinson Family,
15 Inventing the Electronic Computing Machine,
16 'Colossus Arrives Today',
17 Fish Dialects,
18 Fish – Landing the Catch,
19 A Day in the Life of Fish I,
20 A Day in the Life of Fish II,
21 The Technology and Organization of Fish,
22 Transatlantic Fisheries,
23 Siginstitutionalization,
24 Colossus – The Legacy,
A The Baudot. Code with Shift Function,
B The Vernam Cipher,
C Extended Example of 'The First Break',
D Structure of the Lorenz Schluesselzusatzgeraet SZ40/42,
E The Delta Techique,
F Robinson: Block Diagram of Major Function Units,
G Non-machine Problems Identified During the Heath Robinson Period,
H Basic Functional Sub-systems of Colossus,
I Annotated Printout of Colossus 3 run 23/10/44 (Stickleback),
J Colossus 'Processing Tree',
K Sturgeon and Thrasher,
L Bream Message Types and Examples – Early 1944,
M Some Jellyfish Messages from May and June 1944,
N Cribs Used on Dragon,
O Whiting Decode, 5 February 1945,
P 'Hitler as seen by Source',
Q Newmanry Staffing,
A Note on Sources,
Further Reading,

Customer Reviews

Most Helpful Customer Reviews

See All Customer Reviews