Historic innovation in Britain
Paddy Rodgers urges today’s maritime innovators to emulate the perseverance of their predecessors
If we are to learn the lessons of the past and inform our future, it is important to put current innovation and technological solutions into context. We can easily underestimate the contemporary relevance of our past inventors and innovators, but it is a mistake to do so. The oceans are Britain’s lifelines – highways for transporting goods, people and ideas. The importance of these routes to Britain’s survival has led to inventions that address issues of environment, speed, navigation and economic capacity.
However, innovation is not always a solo activity confined within national boundaries. While some inventors worked alone, others built on the results of earlier experiments; and as invention and technological narratives are rarely linear, some inventors arrived at the same solutions simultaneously.
A curious phenomenon has been the reluctance of society, public institutions and government, to implement certain inventions. So an important quality in an inventor is perseverance. The examples below include British inventors who worked with obsessive focus to perfect their designs, or who collaborated and learnt from other scientists before reaching their solutions, and others whose confidence and persistence eventually saw their designs being adopted.
The screw propeller
In the 19th century the desire to move away from a reliance on wind power, which is intermittent, to move cargoes and people around the world was nothing new. The steam-driven paddlewheel had been one way of addressing this – but the engines were heavy and bulky, and in bad weather a paddle could lift out of the water, making the ship yaw abruptly. In warships, the paddle boxes were too exposed to damage to be a long-term solution for any navy. Something better was clearly needed.
In Britain, the invention of the successful screw propeller in the 1830s and 1840s is credited to Francis Pettit Smith, who met the challenge of connecting a propeller via a drive shaft to a steam engine that could accept the thrust. While he was not the first to come up with the idea of a propeller per se, his political and business connections enabled him to refine and experiment on his models, and he worked closely with Brunel. The success of Smith’s propeller on his ship Archimedes, designed to publicise the efficiency of the propeller, led to the Admiralty experimenting with HMS Rattler in 1845. The trials with the Archimedes then led Brunel to redesign the Great Britain with a screw rather than paddlewheels. Great Britain is open to the public at Bristol, where one may appreciate Brunel’s vision of a large iron-built luxury passenger ship driven by a screw propeller that had its origins in Smith’s work.
The marine chronometer
The expansion of European interest in exploring the planet for scientific, political and economic reasons required a greater ability to fix the locations of mariners at sea. The erstwhile lack of precision, especially during long open ocean voyages, not only led to errors in mapping and charting but also was dangerous. Latitude was fixed relatively simply, by calculating the meridional altitude of the sun. However, fixing longitude was considerably more complicated, requiring either complex lunar calculations or knowledge of the precise difference between local time and that of Greenwich.
The work of the Board of Longitude, set up in 1714 to promote the discovery of an effective method, prompted a number of solutions. The most famous, and ultimately successful, was the marine chronometer designed by John Harrison in 1759. However, the success had taken Harrison almost 30 years of design, experiment, deadends and innovation, and a determination to overcome some active resistance within the scientific community. The main practical challenge he faced was the pitching and yawing of ship at sea, which unsurprisingly disturbed a pendulum or dumbbell swing, making timekeeping wildly inaccurate. In addition, a marine chronometer had to be portable – his first design, H1, weighed 72lbs – and had to cope with wide temperature variations.
Captain Cook took a copy of Harrison’s H5, made by Larcum Kendall in 1769, on his second Pacific voyage (1772–1775), and when Cook arrived back at Plymouth after three years at sea, it gave an error of less than 8 miles. This chronometer is held by the National Maritime Museum, while Harrison’s four incremental designs, H1 to H4, are on display at the Royal Observatory, Greenwich.
Lightning conductors
As Britain’s sphere of interest and influence expanded over the globe, with an increase in military presence, the dangers lightning presented to wooden warships developed into a serious problem. A lightning strike could be catastrophic, resulting in masts and yards exploding into splinters, crew killed, and spars, rigging and sails set on fire. To publicise the dangers, William Snow Harris, a doctor with a passionate interest in electricity, produced a pamphlet listing 235 warships that had been struck by lightning between 1790 and 1839, and the injuries and deaths to crew.
The lightning conductors used on British warships had originated in the 1760s, invented by Dr William Watson. But his was an unsatisfactory arrangement, relying on sailors hoisting a copper chain up the mast; the chain got in the way of the rigging, sails and yards, and lightning could melt the links. Britain was behind France and America in addressing this problem, and it took 22 years of perseverance by Sir William Snow Harris to effect a more permanent solution. The National Maritime Museum has examples of some plans he submitted to the Admiralty for trials. Harris’s invention was far superior to earlier approaches. He proposed that a double set of copper plates be nailed onto the masts, slightly inlaid in the wood and overlying each other so that the ends of the plates in one set overlapped at the middles of the others. The solid continuity of the copper strips was important, to ensure that the electricity was conducted effectively down to the keel and into the water. The Admiralty eventually adopted his design in 1842 in response to Parliamentary pressure, but only after extensive delay and experimentation on warships. For instance, in 1831, HMS Beagle was fitted with Harris lightning conductors for the expedition made famous by Charles Darwin. Fitzroy, Beagle’s captain, reported in Appendix 48 of his narrative: ‘Were I allowed to choose between having masts so fitted and the contrary, I should not have the slightest hesitation in deciding on those with Mr. Harris’s conductors’.
Conclusion
Today, the human race faces a different set of challenges: to protect the marine environment and maritime resources. Some of the problems have actually been created by previous inventions; even so, the past can help inform future solutions. For instance, the greenest form of marine power is wind, and from historic ships such as Cutty Sark at Greenwich, we can learn how to adapt and modify technology to reflect new materials and our more advanced scientific understanding. Shifting the sources of propulsion to renewable and wind power will begin to address the 2.5 per cent of greenhouse gas emissions for which the maritime sector is responsible.
Harrison’s work to improve navigation has been continued by others. GPS now enables ships to be more efficiently navigated, saving time and fuel. This is leading to remotely and autonomously operated ships. Propellers have continued to develop, building on the experiments of visionaries like Brunel and Smith: a more efficient design, capable of countering the natural movement of ships through a variety of sea states, as well as providing optimal thrust, would save fuel and reduce emissions – and costs. Equally, quieter running propellers will cause less acoustic disturbance in ecologically sensitive areas.
Smith, Harrison and Harris can serve as inspiration for future researchers and designers. Each of those inventors faced his own challenge, whether that was lack of finance, or lack of connections or support, or sheer technological complexity. However, they all persevered or collaborated to bring new ideas and a different perspective in to their innovative work. If maritime industry is to remedy the damage it causes to the health of the marine environment, it requires the same levels of ingenuity and dedication.
Paddy Rodgers is the Director at Royal Greenwich (incorporating National Maritime Museum, Royal Observatory, Queen’s House, and Cutty Sark)