Introduction^[1]

Operation PLUTO was a wartime initiative to transport fuel from England to the European continent to support Allied forces during World War II. The primary pipelines extended from Dungeness to Boulogne and from the Isle of Wight to Cherbourg. After the war, the pipelines were dismantled, and the lead they contained was salvaged. Ironically, much of the lead used to construct the pipelines initially came from buildings damaged by Luftwaffe bombing raids.

Operation PLUTO (Pipeline Under The Ocean) was an ingenious and pivotal project during World War II that aimed to supply Allied forces with an essential resource—fuel—directly from England to the European mainland following the D-Day invasion. This paper details the planning, execution, and legacy of PLUTO, underscoring its role in Allied success and post-war engineering.

Operation PLUTO represents a landmark achievement in military logistics and engineering innovation. Designed to address the critical need for fuel during the Allies’ advancement post-D-Day, PLUTO combined cutting-edge technology with strategic foresight, significantly impacting the war’s outcome.

Picture: Operation Pluto – location of pipelines
Citation: Operation Pluto. (2024, November 24). In Wikipedia. https://en.wikipedia.org/wiki/Operation_Pluto
Attribution: The Library of Congress. The original artist is Ashley T. Walker. Drawn in 2009 for Historic American Engineering Record (HAER) VA-132

Background and Strategic Importance

As the Allied forces prepared for the monumental D-Day invasion, their planners faced a daunting logistical riddle. Victory would depend not just on the valour of soldiers or the brilliance of generals but on something far more prosaic yet equally vital: fuel. Armies did not move on their stomachs alone—they needed their fuel tanks. The question was not whether the Allies could land in Normandy but whether they could sustain their relentless advance across Europe.

Traditional methods of fuel transport—barrels hauled by ship and truck—were out of the question. The choppy English Channel was a treacherous gauntlet under constant watch from the Luftwaffe, and German U-boats lurked beneath the waves, ready to turn any supply convoy into a blazing inferno. Something bolder, something unprecedented, was required.

This is where Operation PLUTO emerged—not just as an engineering marvel but as a lifeline of survival. It was a feat that demanded secrecy, audacity, and the courage to imagine the impossible: undersea pipelines stretching from England to France, pumping vital fuel directly to the front lines. The stakes were enormous—without this supply chain, even the bravest troops might falter, their tanks and trucks stranded, their momentum lost.

With D-Day looming, the Allies raced against the clock. The channels would soon echo with the roar of engines and the crash of artillery, and those engines would need an unbroken river of fuel. Operation PLUTO was more than a logistical solution; it was a gamble on the ingenuity of engineers and the resilience of innovation under fire.

Initial Proposals and Conceptualisation

The strategic concept of PLUTO was proposed as early as 1942 by Geoffrey William Lloyd, Secretary for Petroleum^[2], with significant contributions from Arthur Hartley, chief engineer at the Anglo-Iranian Oil Company.

PLUTO was commissioned in response to the immense fuel demands anticipated for Operation Overlord, the Allied invasion of Normandy. Traditional fuel transport methods, such as oil tankers, were vulnerable to German U-boat attacks and adverse weather conditions, necessitating a more secure and efficient supply line.

The PLUTO project was developed under the utmost secrecy, with two main types of pipelines being developed:

• HAIS Pipes: Engineered for flexibility and durability, these were designed by the Anglo-Iranian Oil Company and Siemens Brothers. The pipes were made of flexible steel with a three-inch diameter lead core adapted from submarine telegraph cables.
• HAMEL Pipes: Developed by Henley’s and BICC, these were less flexible (made of lead and steel) but offered greater resistance to external damage.

Recognising the logistical challenges ahead, the project was backed by top military strategists, including Admiral Mountbatten, leading to a top-priority secret development.

The commander for the operation was Captain John Fenwick Hutchings, CBE, DSO.

Development and Engineering Challenges

Construction began in 1943 with two primary routes:

• From the Isle of Wight to Cherbourg: Approximately 70 miles using mainly HAIS pipes.
• From Dungeness to Boulogne: Slightly shorter, utilising both HAIS and HAMEL pipes.

Picture: Captain J. F. Hutchings, commander of Operation Pluto
Citation: Operation Pluto. (2024, November 24). In Wikipedia. https://en.wikipedia.org/wiki/Operation_Pluto
Attribution: Royal Navy official photographer: Zimmerman E A (Lt), Public domain, via Wikimedia Commons
This work created by the United Kingdom Government is in the public domain

Laying pipelines across the English Channel was an audacious endeavour that stretched the limits of engineering and human endurance. The waters between England and France were no friendly avenue; they were a battlefield in themselves, buffeted by strong currents and patrolled by enemy forces. The engineers tasked with this project worked under immense pressure, knowing that even a small misstep could jeopardise the entire Allied advance.

At the heart of the operation was the quirky yet ingenious ‘conundrum’—a massive, floating spool that unwound the pipeline like a thread from a bobbin. These conundrums, each weighing an astonishing 250 tons, became symbols of the daring enterprise. ‘We joked about christening one as HMS Hairbrained,’ recalled Chief Engineer Arthur Hartley, a leading figure in the project. ‘But deep down, we knew these unwieldy giants would either make or break the mission.’

Every decision carried weight. To keep the operation cloaked in secrecy, the pipes were shipped under cover of darkness, and workers often laboured under tight-lipped silence, knowing loose words could travel far. ‘We couldn’t even tell our families what we were building,’ said a technician who only years later learned the true scale of his contributions. ‘It felt like crafting an invisible bridge to victory.’

Despite the challenges, the engineers pressed on. With each pipeline laid, they bent technology to their will, their accomplishments echoing a spirit of ingenuity and perseverance that would become the hallmark of Operation PLUTO.

‘HMS Conundrum’ was an unofficial name given to the large drums used for laying the World War II Normandy landings PLUTO pipeline. The drums were cone-ended, hence the abbreviation CONUN and were used in the sea, hence the HMS Conundrum nickname. They were 30 feet in diameter and weighed 250 tons.^[3]

Technical Innovations and Operation

The laying of pipelines involved overcoming numerous challenges – such as deep waters, strong currents, and maintaining secrecy. Specialised “conundrums”—large floating drums—were essential for efficiently unspooling the pipelines across the seabed.

Picture: Laying the pipeline: a Conundrum being moved into position into a specially constructed dock in preparation for the winding on of the pipe.
Citation: Operation Pluto. (2024, November 24). In Wikipedia. https://en.wikipedia.org/wiki/Operation_Pluto
Attribution: Official photographer., Public domain, via Wikimedia Commons

Operation PLUTO became operational shortly after D-Day, and the first fuel started flowing through the pipelines. At its peak, PLUTO delivered thousands of tons of fuel daily, significantly contributing to the success of Allied operations in Europe. The pipelines operated successfully until the end of the war, after which they were decommissioned and dismantled.

Pipeline Development and Pumping

HAIS Pipeline Development
The HAIS pipeline, developed by Anglo-Iranian, Siemens Brothers, and the National Physical Laboratory, was a groundbreaking solution to wartime fuel supply challenges. Named after its developers (Hartley-Anglo-Iranian-Siemens), the HAIS system featured a 2-inch diameter lead inner pipe capable of delivering 3,500 imperial gallons per day under extreme pressure. This robust system, reinforced with layers of asphalt, vinylite resin-impregnated paper, steel tape, jute, and a protective steel wire casing, was tested successfully across the River Medway and the Firth of Clyde. The innovative use of flexible materials allowed the pipe to be deployed efficiently by specialised cable ships like HMS Holdfast, demonstrating its resilience through trials that included surviving bomb impacts and anchor drags. Full-scale production started in August 1942, involving significant investment, but specifics on costs were often absorbed by companies with the expectation of government reimbursement.

HAMEL Pipeline Development
In response to lead shortages, the Hamel pipeline was developed as an alternative using more readily available materials like mild steel. Engineered by Bernard J. Ellis of Burmah Oil and H.A. Hammick of Iraq Petroleum, the Hamel pipe was a stiffer 3+1/2 inch design, less suitable for coiling but ideal for towing in large, drum-like structures called Conundrums. Despite its rigidity, the Hamel pipe’s design included a broaching tool to clean metal swarf from welds, ensuring integrity. Extensive tests confirmed its viability, leading to its deployment across strategic locations, including the Solent. Six Conundrums were constructed at a cost of £30,000 each, showcasing significant financial commitment to the project’s success. This dual-pipeline strategy ensured a reliable fuel supply to Allied forces during critical phases of World War II.

Picture: Shanklin Chine – P.L.U.T.O. Sign Descriptive sign about the Pipe Line Under The Ocean, from WW2. A small section of this military history still remains in Shanklin Chine. http://www.shanklinchine.co.uk/page12.html
Attribution: Peter Trimming / Shanklin Chine – P.L.U.T.O. Sign
This file is licensed under the Creative Commons Attribution-Share Alike 2.0 Generic license.

Pumping
In the shadow of war’s darkest days, secrecy became the cornerstone of the operations of the Petroleum Warfare Department^[4]. By 1943, they had transformed Sandown on the Isle of Wight and Dungeness on the Kent coast into clandestine hubs of innovation. Under cover of night, trucks rumbled into these sites, their cargoes hidden beneath tarpaulins that shielded not just equipment but the very lifeblood of an Allied victory.

To the untrained eye, these pumping stations were nothing more than sleepy seaside villas or quaint amusement parks—a masterstroke of camouflage. Even the maps of the day betrayed no hint of their existence, and drivers received their cryptic instructions via public phone booths, ensuring no paper trail could reveal their purpose. As one worker recalled, ‘We knew we were building something important, but we didn’t realise we were fueling history.’

Each station housed thirty diesel-powered pumps and four large electric pumps, enabling a significant fuel pumping capacity. These stations were linked to the Avonmouth-Thames pipeline and further connected to Operation Pluto’s undersea pipeline system by early 1944. The French counterpart stations, codenamed “Bambi” for Cherbourg and “Dumbo” for Ambleteuse, were chosen by mid-1943.

Additionally, as part of the Operation Overlord deception plan, a fictitious oil facility was built at Dover. Designed by architect Basil Spence, this elaborate setup included simulated pipelines and storage tanks designed to mislead German reconnaissance. Enhanced with wind machines and smoke screens to mimic activity, the site even hosted visits from notable figures such as King George VI and General Dwight D. Eisenhower, furthering its guise as a legitimate operation.

In 1943, sophisticated pumping stations were established at Sandown on the Isle of Wight and Dungeness in Kent to support Operation Pluto. Each station was outfitted with thirty diesel-powered reciprocating pumps and four high-capacity electric centrifugal pumps from Byron Jackson Company. These installations could pump 400,000 imperial gallons of fuel daily at a pressure of 1,500 psi. Integrated into the broader fuel network, both stations drew from the Avonmouth-Thames pipeline, which had a total capacity of 135,000 long tons per month.

Additionally, a 70-mile branch line linked Dungeness to Walton-on-Thames, and a 22-mile connection ran from Sandown to the largest oil refinery in the United Kingdom at Fawley Refinery in Hampshire on Southampton Water. Corresponding sites in France were selected in June 1943. Sandown would be connected to the port of Cherbourg, a distance of over 65 mi (120 km). Dungeness was connected to the port of Ambleteuse. In keeping with the Disney theme suggested by Pluto, the former was codenamed Bambi and the latter Dumbo. All these crucial pipeline connections were fully operational by March 1944, ensuring a robust supply chain to support the Allied forces after D-Day.

Effectiveness of Operation PLUTO

Operation PLUTO’s initial deployments faced challenges, with the first attempts in August 1944 failing due to technical issues. Success was achieved later: the Hais pipeline commenced operation on 22^nd September 1944, delivering 56,000 imperial gallons per day. However, both the Hais and Hamel pipelines experienced failures on 3^rd October 1944, due to increased pressure, leading to the cancellation of the Bambi pipeline the following day – after delivering 935,000 imperial gallons in total.

Description: [Cropped] Pipeline PLUTO – American Soldier
Pipeline PLUTO – Soldat americain.jpg
Attribution/Copyright holder: Conseil Régional de Basse-Normandie / National Archives USA, Attribution, via Wikimedia Commons

The Dumbo pipeline proved more reliable, starting operations on 26^th October 1944 and continuing until the end of the war. Adaptations and extensions enabled it to transport fuel to Calais, enhancing logistical support through better railway connections. By December 1944, a network of pipes was delivering 1,300 tons of petrol daily. While the Hamel pipes required periodic repairs, the Hais lines remained intact throughout their operation. By August 1945, Dumbo had transported 180 million imperial gallons of petrol.^[5]

Overall, Operation PLUTO contributed approximately 8% of the petroleum products supplied to Allied forces in North West Europe, costing an estimated £4.4 million (equivalent to approximately £243 million in 2024). Post-war, 85% of the pipeline material was salvaged, recovering materials valued at £400,000, which exceeded the cost of recovery.

Economic Aspects and Recovery

The exact cost of Operation PLUTO is hard to determine, but it was a significant investment. The cost was justified by the strategic advantage it provided, ensuring a continuous and reliable fuel supply which was crucial for the mobility and effectiveness of the Allied forces.

After the war, the pipelines were dismantled, and the valuable materials, particularly lead, were salvaged. Much of the lead used in the pipelines came from buildings damaged in the Blitz, adding an ironic twist to the story as these materials, once destroyed by the enemy, were repurposed to aid in his defeat.

Historiography and Legacy

PLUTO has been studied extensively as a hallmark of innovative wartime engineering. The success of the operation not only demonstrated the Allies’ ability to leverage technology in warfare but also set precedents for peacetime engineering projects, particularly in pipeline technology and logistics.

A key component of PLUTO’s success was the development of the Hamel pipe, which addressed wartime shortages of lead by using mild steel. The creation of the Hamel pipe was the culmination of years of research and collaboration, notably involving the Institute of Welding^[6] and Stewarts & Lloyds^[7]. Beginning in 1938, the Institute of Welding conducted extensive studies on techniques like flash butt welding and oxy-acetylene welding to determine their efficacy in joining steel pipes. These findings, first documented in a pivotal 1941 paper on Pressure Pipe Welding, provided the technical foundation for Hamel pipe production.

Stewarts & Lloyds, a leading British steel manufacturer, played a critical role in translating this research into practice. Their facilities produced the steel tubes required for the Hamel pipes, employing cutting-edge techniques to ensure strength, reliability, and resistance to corrosion. Their partnership with the Institute of Welding was pivotal in refining flash butt welding—a method that created seamless, durable joints capable of withstanding the immense pressures of fuel transport and the harsh conditions of the English Channel.

The practical application of these innovations is evidenced by contemporary films showing Stewarts & Lloyds’ welding techniques in action. Their contributions ensured that the Hamel pipes were not only feasible but robust enough to meet the operational demands of Operation PLUTO. Treated with protective coatings and rigorously tested, the pipes delivered a reliable and uninterrupted flow of fuel to Allied forces, overcoming logistical challenges that traditional methods like tankers and fuel drums could not.

Enduring Influence
The innovations pioneered during the development of the Hamel pipes—especially in welding and pipeline construction—set benchmarks that would shape post-war industries. From offshore oil drilling to modern pipeline maintenance, the techniques and materials developed for PLUTO continue to influence engineering practices worldwide. Stewarts & Lloyds’ role in this landmark project is a testament to how industrial expertise and collaborative ingenuity can redefine what is possible, even in the face of extraordinary challenges.

Conclusions

Operation PLUTO represents a masterstroke of engineering ingenuity and logistical brilliance during World War II. Conceived to address the critical fuel supply needs of Allied forces advancing across Europe after D-Day, it became an indispensable lifeline for the liberation campaign. The operation’s success was the result of meticulous planning, groundbreaking innovation, and the dedication of thousands of individuals who worked tirelessly under conditions of extreme secrecy.

The Workforce Behind PLUTO
Over 1,000 individuals were directly involved in laying the pipelines, from engineers and technicians to skilled labourers and naval personnel. Workers were drawn from a mix of military units, oil companies, and civilian contractors. Recruitment emphasised technical expertise and reliability, often targeting employees from firms like the Anglo-Iranian Oil Company (now BP), Siemens Brothers, and Henley’s, who had prior experience in cable-laying or pipeline construction. Despite their diverse backgrounds, they were united by a shared purpose and the knowledge that their contributions would play a vital role in the war effort.

Exploring Alternatives
Before PLUTO was devised, the Allies considered traditional methods, such as using oil tankers and fuel drums to transport fuel across the English Channel. However, these options posed significant risks due to the vulnerability of convoys to German U-boat attacks and the logistical challenges of unloading fuel during active combat operations. Aerial refuelling and other nascent ideas were dismissed as impractical for the scale required. PLUTO offered a solution that combined efficiency, safety, and a lower operational footprint—delivering fuel directly to where it was needed while avoiding the constant threat of enemy attacks.

Maintaining Secrecy
Secrecy was paramount to the success of Operation PLUTO. The project was disguised under innocuous codenames, and its infrastructure was cleverly camouflaged. Pumping stations were hidden as seaside villas or amusement parks, and their locations were removed from maps. Workers were sworn to confidentiality, with strict penalties for breaches, and communications were deliberately obfuscated—delivery instructions were issued verbally or via public phone booths to prevent a paper trail. Even the pipelines themselves, laid under cover of darkness, were an invisible feat, unseen by enemy reconnaissance. This comprehensive security strategy ensured the operation remained unknown to the Axis powers until its fuel began flowing to the front lines.

Lasting Contributions
The lessons of PLUTO have left a significant legacy for post-war civil engineering and industry:

• Undersea Pipeline Technology: PLUTO pioneered techniques that are now standard in offshore oil and gas operations.
• Welding and Materials Innovations: Advanced welding and corrosion-resistant materials developed for PLUTO have influenced pipeline construction worldwide.
• Logistical Coordination: The operation’s management offered a blueprint for handling large, complex projects involving multiple agencies and geographies.
• Remote Monitoring: Early techniques for monitoring and repairing underwater pipelines became the forerunners of modern sensing technologies.
• Secrecy and Site Integration: The innovative use of camouflage and discreet infrastructure integration has inspired similar strategies in sensitive environments.

By August 1945, PLUTO had delivered over 180 million gallons of fuel, constituting a vital 8% of the Allied petroleum supply in Northwest Europe. Its impact was profound, ensuring the operational mobility of Allied forces and accelerating the defeat of Axis powers.

A Testament to Human Ingenuity
Operation PLUTO was not just an engineering triumph but also a testament to the power of innovation under pressure. It transformed logistical challenges into opportunities for creativity, proving that necessity is the mother of invention. The operation remains a symbol of Allied resolve and a cornerstone of modern pipeline technology.

In the legacy of Operation PLUTO, there are enduring lessons about perseverance, collaboration, and the ability of humanity to overcome seemingly insurmountable obstacles. Its story is one of courage and ingenuity—a fitting tribute to the countless individuals who contributed to this remarkable chapter in history. In the end, it was more than an engineering marvel; it was a testament to the ingenuity, courage, and quiet heroism of those who built a pipeline to victory—an invisible bridge across the depths of war, fuelling not just tanks and other military vehicles, but the liberation of a continent and the enduring promise of innovation in the face of adversity.

Description: The tug Britannic lays the seventeenth pipeline to Boulogne.
Citation: Operation Pluto. (2024, November 24). In Wikipedia. https://en.wikipedia.org/wiki/Operation_Pluto
Attribution: Royal Navy official photographer: Zimmerman E A (Lt) – This photograph A 28817 comes from the collections of the Imperial War Museums. Public Domain.

Sources and Further Reading

• http://www.dday-overlord.com/en/battle-of-normandy/supply/pluto
• https://aoghs.org/petroleum-in-war/secret-pipelines/
• https://d-dayrevisited.co.uk/d-day-history/planning-and-preparation/operation-pluto/
• https://en.wikipedia.org/wiki/HMS_Conundrum
• https://en.wikipedia.org/wiki/Operation_Pluto
• https://engineersatwar.ww2.imeche.org/wp-content/uploads/2019/08/imeche_proceedings_hartley_pluto.pdf
• https://romneymarshhistory.co.uk/pluto
• https://shanklinchine.co.uk/2018/07/new-light-on-operation-plutos-wartime-story/
• https://www.combinedops.com/pluto.htm
• https://www.dday-overlord.com/en/battle-of-normandy/supply/pluto
• https://www.historicmysteries.com/history/operation-pluto/37819/
• https://www.iwm.org.uk/collections/item/object/1060008558
• https://www.sciencefocus.com/science/does-the-pluto-pipeline-under-the-ocean-still-exist
• https://www.theweldinginstitute.com/insights/13090802
• https://www.warhistoryonline.com/world-war-ii/operation-pluto-oil-gasoline-game.html

YouTube Videos

• https://youtu.be/RqKxeYZLNmU
• https://youtu.be/Hv3YB1uVy5Y
• https://youtu.be/0GgZUbGltNs
• https://youtu.be/FdMuIc3Qzn8
• https://youtu.be/6jIW2g7IkFA
• https://youtu.be/qCt_ykszXOQ

Books

• Fuelling the Wars: PLUTO and the Secret Pipeline Network, by Tim Whittle, published by Folly Books, availability unknown
• Operation Pluto eBook, by Ren Cooper – Available as a Kindle eBook from https://www.amazon.co.uk/Operation-Pluto-Ren-Cooper-ebook/dp/B0D9YY7F11/
• PLUTO: Pipe-Line Under the Ocean – The Definitive Story, by Adrian Searle, published by Shanklin Chine, available from https://www.amazon.co.uk/PLUTO-Pipe-Line-Under-Ocean-Definitive/dp/0952587602/
• Where Pluto Crossed the Path: Rambles with Purpose Across the Isle of Wight, by Tim Wander, published by New Generation Publishing, available from https://www.amazon.co.uk/Where-Pluto-Crossed-Path-Rambles/dp/178955750X

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End Notes and Explanations

1. Source: Compiled from my research using information available at the sources stated throughout the text, together with information provided by machine-generated artificial intelligence at: bing.com [chat] and https://chat.openai.com. Text used includes that on Wikipedia websites is available under the Creative Commons Attribution-ShareAlike License 4.0; additional terms may apply. By using those websites, I have agreed to the Terms of Use and Privacy Policy. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organisation. ↑
2. Explanation: Secretary for Petroleum was a British government position created during World War II to oversee and coordinate Britain’s petroleum supplies and usage. The office emerged as part of the broader war effort to ensure the efficient management of critical resources, particularly fuel, which was essential for both military operations and civilian needs. The role involved:
   • Overseeing the import, storage, and distribution of petroleum products.
   • Ensuring fuel availability for key sectors, including the military, industry, and transportation.
   • Collaborating with allied nations and companies to secure petroleum supplies under wartime conditions.

   During the war, Geoffrey William Lloyd served as Secretary for Petroleum and played a significant role in initiating and supporting innovative projects like Operation PLUTO, which addressed the Allies’ logistical challenges related to fuel supply. ↑

3. Source: https://en.wikipedia.org/wiki/HMS_Conundrum ↑
4. Explanation: The Petroleum Warfare Department (PWD) was led by Sir Donald Banks, a British civil servant and former military officer, who became its Director upon its establishment in 1940. Banks brought a blend of administrative acumen and technical insight to the department, which was critical for managing its innovative but unconventional operations. As Director, Banks oversaw the department’s wide-ranging activities, ensuring collaboration between government agencies, private companies, and scientific experts. His leadership helped turn experimental ideas into practical wartime applications.Other notable figures were Geoffrey Lloyd, the Secretary for Petroleum (see above), who provided high-level political oversight and direction to the PWD – his office was instrumental in ensuring the department’s projects received the necessary resources and priority, and Arthur Hartley, Chief Engineer of the Anglo-Iranian Oil Company (later BP) who contributed engineering expertise, particularly in the development of undersea pipelines for Operation PLUTO.The PWD operated with a significant degree of secrecy, and its unconventional ideas often required robust advocacy and coordination, which Sir Donald Banks effectively managed. ↑
5. Source: https://www.theweldinginstitute.com/insights/13090802 ↑
6. Explanation: The Institute of Welding is now part of TWI (The Welding Institute). TWI is a renowned organisation specialising in welding, joining, and materials engineering. It evolved from the Institute of Welding, which was established in 1923, to advance research and practice in welding technology. Over the decades, the organisation expanded its scope to include broader areas of materials science and engineering, becoming TWI. The Institute of Welding played a critical role in developing welding technologies during World War II, including those used in Operation PLUTO. In 1946, the Institute of Welding became part of a larger organisation, the British Welding Research Association (BWRA). Later, these entities merged under the name TWI. Today, TWI is a global leader in engineering research and technology, providing consultancy, training, and research in fields like welding, materials joining, and additive manufacturing. See more at: https://www.twi-global.com/ ↑
7. Explanation: Stewarts & Lloyds was a steel tube manufacturer with its headquarters in Glasgow. The company was created in 1903 by the amalgamation of two of the largest iron and steel makers in Britain: A. & J. Stewart & Menzies, Coatbridge, North Lanarkshire, Scotland; and Lloyd & Lloyd, Birmingham, England. The steel industry was nationalised for the second time, and the company became part of the British Steel Corporation in 1967. See more at https://en.wikipedia.org/wiki/Stewarts_&_Lloyds ↑