Sea and Ships

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Architects: Basil Spence and Partners ◦ Theme Conveners: C. Hamilton Ellis and Nigel Clayton
Display Designers: James Holland and Basil Spence, O.B.E.

Our ancestors came by sea and found here natural havens for their craft. We still live on the sea and by it, using this same coastline as the childbed of our inheritance – the building of ships for the world and for ourselves.

The years before steam

Several nations have had their spell of preeminence at sea. The British tradition has been continuous.

We are proud enough of our great days of sail, but we are prouder still that most of the changes that a growing world demanded were made by our shipwrights and designers. To-day, we still make the pace in the design, construction and operation of ships for every purpose that the modern world requires.

The days of change

About the time that fast sailing ships were reaching their perfection, iron hulls were replacing wood. Sail’s rival in propulsion – the steam engine – was also gaining ground. In 1843, for example, the Great Britain, though built basically as a six-masted sailer, was fitted with a powerful steam engine and a single propeller. The Great Eastern, launched in 1858, and for many years the world’s greatest ship, was equipped with not only engines to drive her propeller but a paddle engine too.

By the late ’70’s steel was replacing iron in the hulls, and new types of machinery made steam propulsion more efficient and reliable. British industry was ready for the change and took the lead at once in building ships of steel.

Modern propulsion

Modern ship propulsion dates from 1897, when Sir Charles Parsons gate-crashed the Diamond Jubilee Naval Review with his experimental ship Turbinia and showed a clean pair of heels to the fastest of the Queen’s ships. This startling demonstration was the first time the performance of the steam turbine had been seen by a large and influential public. From that moment its development was rapid.

A more recent, though not universal, development is the introduction of electric propulsion, whereby the power of high-speed turbines is transmitted electrically to the propellers, which must turn comparatively slowly.

But the development of turbo-electric propulsion could not have happened without simultaneous development in three other fields. One was the change from coal to oil burning. Another was in metallurgical research, which produced materials that can retain their strength at the very high temperatures needed in the turbine. The third improvement has been in gearing. This was made possible by the development of machine tools to the pitch where they could cut metals with an accuracy of a thousandth of an inch.

Continuation of metallurgical and engineering progress such as this is going to establish the marine engine of the future – the combustion, or gas, turbine. Metallurgists have already found the necessary new materials that can retain their strength at the required temperatures, which are far higher than occur within a steam turbine.

The displays of marine propelling machinery in this section also show the rival of the steam turbine – the modern heavy oil engine. This engine is the product of an original invention of Herbert Akroyd Stuart. After a period of development on the Continent, the lead in its design and manufacture came back to Britain, which is still ahead in making the propelling machinery for motor ships.

Propellers

To look at propellers seem large, simple things, but their design and finish is far from being a simple job. All propellers for big ships are tailor-made for the one hull they must thrust through the water. Every dimension is precisely calculated, and the finish of the propeller, after it has been cast, is precision work.

In the designing of propellers, the pitch of the blade has to be varied along its length since the water does not flow past it uniformly. As no hull is precisely the same as another, these slight variations have to be worked out during trials with scale models in experimental tanks, such as the one demonstrated further on in this Pavilion.

There is still a number of propeller problems to which we do not know the answers. Two of these which are being investigated now are cavitation and “singing”. Cavitation is pitting caused by the attack of sea water. It ruins the precision work done in the finishing shops and cuts down efficiency. “Singing” propellers result from vibration in the blades. This is picked from the water by the hull and gives the ship an irritating sound-effect.

Building a ship

The great business and industry of building ships is shown in the central area of this Pavilion. So complex a story cannot be described in full; but the displays give a series of impressions of the more important events in the birth and growth of a new vessel.

The owners’ needs in cargo or passenger space, speed and economic outlook give the designers the first indication of the dimensions of the ship; but her design, as a robust, well-balanced structure capable of operating on the routes desired, turns out to be a compromise between many more considerations than these.

When working drawings have been produced for every possible part of the ship, the shipyard personnel take over, staying on a high black floor called the “loft”, where the shape of the vessel, full size, is laid down in white lines.

The growth of the ship from this beginning, and the many crafts and skills that bring it about, are summarised here. After some displays of fitting out, the sequence culminates in a summary of modern trends in design.

The ship testing tank

It is accepted practice nowadays for new ships to be constructed first in model form and for their underwater characteristics to be studied (and, if necessary, modified) during trials in an experimental tank.

An 80-foot section of such a tank is included in this Pavilion, and tests will be carried out here with model hulls. The demonstrations of the techniques used have been arranged with the cooperation of the National Physical Laboratory, which has played a leading part in developing this application of science to shipbuilding.

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Harvesting the sea

So far, the displays have been mainly conceded with passenger and cargo ships. Now the story turns to an equally important facet of our maritime life – the sea fisheries.

The methods of this great British industry depend primarily on the habits of the fish themselves. Some, like the herring and mackerel, live and feed near the surface and are caught by drift nets; others, like cod and plaice, live on or near the sea bottom and are caught in trawls. A third group, the halibut, for example, are best fished by means of long lines.

The British fishing grounds have always been expanding and now stretch from the near waters around the coast, through the middle waters of the Faroes to the farthest grounds of Iceland and the Arctic Circle. As the area of fishing has grown, so has the expanse of unprofitable water. Now, to aid the experience and intuition of the skippers, organised scientific research is finding out more and more about the growth, the feeding and the movements of the fish so that their whereabouts and numbers can be predicted with some certainty. Connected with this work are studies of over-fishing the productive grounds so that the stock of fish in North European waters shall be rationally exploited.

Preserving and distributing the catch

Fish is one of the most perishable of foods, and with the lengthening of the sea voyage to the fishing grounds the problem of their preservation begins on board. Science and industry are very alive to the necessity of this, and there has been considerable advance in the methods used in recent years.

An even larger problem is the handling, packing, storage, transport and distribution of the fish ashore, and here, again, are notable improvements worthy of display.

The catches are largely seasonal and their weight may vary daily. It is only by methods of storage that do not detract from quality that this uneven supply can meet a constant demand.

Fishing gear and vessels

This section illustrates how British industry is providing the fisherman with the essentials for his job. As well as improved ships and more efficient gear, the fisherman can now rely also on a wide range of modern equipment for navigation and for the location of fish. Examples of the way he is now served are displayed here.

Special ships for special purposes

Britain is not only pre-eminent in the quality of the ships she builds, but she constructs more ships for specialised purposes than any other nation. This is the theme of the culminating section of this Pavilion.

A bold display of the stems of three very different types of vessel illustrates the variety in result. They are a whale factory ship, a passenger liner and a large tanker for British oil.

The central exhibit is a model of a floating dock, containing a modern liner. Around this are examples of twenty-four different vessels, all specialised for a particular kind of duty.

The great business of operating these and other types of ship is the subject of the Sea section in the neighbouring “Transport” building.