Science and Industry

on the World Today

CALDER HALL, at Cumberland, England, is the first big atomic pile in the world to produce electrical energy on an industrial scale. It is the pioneer unit in an atomic energy program far more extensive than anything that has taken shape in the United States. The visitor finds himself dumped off the overnight train from London at dawn. The tiny station is only a few yards from the sand and rocks that rim the chilly waters of the Irish Sea, while off to eastward are the gray Cumberland hills of the Lake District.

Guided by a friendly technical expert, the visitor eventually climbs long flights of iron stairs which lead to the inner sanctuary, the charge face where the pile is loaded with uranium fuel cartridges. The face of the pile forms the steel-plate floor of an enormous open room. Every foot or so there is a two-inch hole, now carefully plugged, through which the fuel cartridges are dropped down through many feet of concrete sheathing into the pile itself— graphite blocks tightly packed into a huge metal pressure vessel.

There is no roar of energy. The pile produces energy only in the form of heat. Carbon dioxide is circulated through the pile, picks up the heat, and transports it to a heat exchanger, where it is transferred to water that becomes steam to drive the generator turbines.

The pile itself is controlled by one man at a desk in a cool green room. Facing him is a bank of instruments that supplies a second-to-second report on everything that happens in the pile. At his hand is a bright red button. Should there be a hint of trouble, a touch will send control rods sliding into the pile to absorb electrons and halt fission. So far, the British atomic energy program has been carried out without the loss of a single life.

Because Calder Hall simultaneously manufactures plutonium and produces electric power, it consumes about one third of the electricity it produces in its two piles. Nevertheless it turns 60 to 65 megawatts into the national electricity grid, and its capacity is now being doubled with two more reactor units nearing completion.

Cheap power ahead

Calder is, however, only the pioneering installation of a program that within a decade will provide 15 per cent of Britain’s electrical energy needs. Already four nuclear power plants are being built. Each is larger than its predecessor, with the latest one, at Hinkley Point in Somerset, designed to have a half-million megawatt capacity.

Present plans call for the addition of 6000 megawatts of electrical generator capacity in nuclear plants by 1966. It is estimated that conventional plants of this capacity would use 10 million tons of oil. or 18 million tons of coal a year. The atomic plants are expected to cost about 750 million pounds more than equivalent conventional plants, including 180 million for the original charge of uranium fuel, which will probably last fourteen years or more. The net effect of the relatively high capital costs and low fuel expense of the atomic plants is to make electricity from nuclear plants more costly at the present time than that produced by coalor oil-burning plants.

By 1962-1963, however, increased efficiency in design is expected to give the atomic stations a slight advantage, while by 1970 nuclear power is expected to be appreciably cheaper than conventional power produced in Britain. The engineers who designed one of the atomic plants now under construction are said to have already improved their techniques so they can now design a pile of the same size that would turn out more than double the electrical output, with a 20 per cent drop in cost per kilowatt.

This increased efficiency is not all gravy. British cost estimates for the future depend upon using the atomic plants for the base load, with the plant operating practically continuously so that high capital costs are spread over as many kilowatthours as possible. Increased atomic plant efficiency, however, means that fewer units will be needed to meet the base demand. This creates a serious economic problem for the companies that have trained expensive teams of scientists and engineers for atomic plant design.

There are other problems, notably an aesthetic one. The British are acutely aware that nineteenth century industry blighted their countryside. They are determined not to have it happen again. Among the atomic plants under discussion is one for North Wales, scenically beautiful but economically depressed. Local people are eager to have the plant for the jobs it will provide, but letters of protest are reaching the London papers from all over England. One solution proposed is to put plants underground. This would add to high construction costs, but in an underground plant earth could replace some of the expensive shielding, while less costly foundations would be needed to carry the great mass of the pile.

These problems will presumably one day face us in the United States. That they do not yet confront us, that our own atomic power program is nowhere near as advanced, is due to a striking difference in circumstances. Britain is running out of coal, while political pressures threaten its sources of oil overseas. It vitally needs new energy sources at home. The United States has large supplies of relatively inexpensive fuels. With no pressing need of costly nuclear power at the present time, we can afford to go slow, to experiment with many techniques, and to benefit by the experience of others.

Liquid gas from Texas

Some foggy morning next winter a London housewife will start her breakfast preparations by lighting a jet of natural gas from Texas. The gas will not have reached her stove by a 3000-mile suboceanic pipeline, but by a method almost as spectacular: a ship. A specially designed tanker is going into service carrying 2000 tons of frozen liquefied natural gas — methane — at 260 degrees F. below zero.

The ship-borne gas experiment is being made by the British Gas Council in collaboration with an American firm called Constock Liquid Methane Corporation, a joint venture of Continental Oil Company and Chicago Stockyards Company. It is hoped that the tanker gas will prove considerably less expensive than the gas that Britain must now manufacture from costly imported oil or its dwindling supply of carbonization coal.

Under the plan, methane from Gulf Coast oil fields in Texas will be liquefied by a water-borne plant. Refrigerating the gas not only liquefies it but condenses it to 1/600 of its former volume. The liquid methane is then pumped into a converted cargo ship with four specially designed tanks, insulated on the inside with balsa wood, which can maintain the low temperature during the voyage without additional refrigeration.

On arrival in England, the methane will be pumped ashore to an island in the Thames, where it will be changed back to a gas and piped into London mains. Although Texan gas is being used for the trial run, it is too expensive to fit into the transportation plan permanently. Supplies would probably be obtained from Venezuela or the Middle East for a large-scale operation.

Liquefying methane at extreme low temperature is not new. The world’s first gas liquefaction plant was built in Cleveland, Ohio, in 1940 to store gas for peak loads. In 1944, however, a storage tank released large amounts of liquefied gas into the air, and a tremendous explosion smashed two hundred neighboring houses, killing about one hundred and forty people. The present proponents say they have overcome all the safety hazards both in their ship design and in the tanks that will store the liquid methane in Britain. If natural gas can be successfully carried overseas, liquefaction might provide new markets for wasted and shut-in gases in the world’s oil fields.

Submarine tankers

An even more striking proposal for cutting the cost of imported fuel is the use as oil tankers of enormous, high-speed submarines driven by atomic power plants. The English firm of Mitchell Engineering Ltd. is studying the possibility of 100,000-ton craft to speed across the Atlantic or around the Cape of Good Hope at 50 or 60 knots.

While to the landlubber it might appear easier to slide over the top of the water than to push through it, tank tests carried out for Mitchell by Saunders-Roe, the seaplane manufacturers, indicate that for large hulls at high speeds the opposite is true. An 80,000-ton surface craft traveling at 60 knots would need about three times as much power as the same size hull deeply submerged. The reason for this startling difference is that the surface ship has to contend not only with the natural wind and surface waves on the sea, but with the drag of the water it pushes ahead of it. Actually it would be impossible for a submarine to proceed at any considerable depth in the shallow waters found in many coastal areas, but there is quite a large gain at depths of 200 to 300 feet.

An underwater tanker would probably remain submerged permanently, with the crew reaching surface in port through some sort of retractable conning tower. Since such a vessel would not have to undergo the varying strains of diving and surfacing, it might be relatively lightly built. With the hull almost completely filled with petroleum, the cargo itself would support the hull walls against the high pressures found at cruising depths. The tanks would have to be filled with water as they were emptied of oil in order to keep the sides from being crushed in.

Japan, another petroleum importer, is also considering submarine tankers, though on a smaller scale.

A proposal under study by Mitsubishi Heavy Industries envisages a 30,000-ton craft with a speed of 22 knots.

Dual typewriters

Many branches of science as they become ever more complicated and esoteric develop a whole family of symbols of their own. As a result, the problem of transcribing a technieal manuscript on an ordinary typewriter becomes a stenographer’s nightmare. The Imperial Typewriter Company, a British firm, has met the challenge by linking two complete typewriters side by side, like Siamese twins, thus providing two keyboards and double the usual number of characters. One keyboard has the standard alphabet, the other supplies ninety-odd additional symbols. The two keyboards share a single carriage, which slides back and forth on a rail that runs the length of the double machine. The typist zips the carriage back and forth between units as symbols are needed. Once accustomed to the machine, she can work up considerable speed. The dual-unit typewriter costs two or three times as much as an ordinary office machine.

Even the 184 symbols and letters of a dual unit are not enough for a highly technical manuscript. The manufacturer has begun work on development of three units for real eggheads.

Slow enough to land

High landing speeds have always been a problem with aircraft that must limit their landing run on the cramped deck of a carrier, and the coming of the jet has not helped matters. In an attempt to shorten the landing run of its Scimitar jet interceptor, the Royal Navy has developed an artificial air stream from the plane’s own engines.

Air from the compressors is blown over the upper surfaces of the plane’s flaps as it comes in for a landing. With this reinforcement, the laminar flow, instead of breaking up when the flaps are depressed, gives the plane a lift that the normal air flow at this speed could not provide. According to the British scientific magazine New Scientist, the plane is able to reduce landing speeds sharply — probably by as much as 15 mph. British manufacturers are reported to have an aircraft engine under development in which a greatly increased flow of air cuts landing speed even more sharply.

Cold light

Since heat and light ordinarily go hand in hand, the amount of light that can be passed through a motion picture projector is usually limited by the amount of heat that the film can stand. An optical firm in Lichtenstein has developed for the British Rank motion picture interests a coldlight “mirror" that enables the light

to be stepped up without a matching increase in heat.

The mirror is made by coating the glass — which need not be of optical quality, since the light does not pass through it — with fifteen extremely thin layers of material, alternately of high and low refractive index. By carefully varying the thickness of the successive layers, it is possible to reflect 98 per cent of the visible light, while most of the heat passes on through. The sandwich surface is so hard that it is resistant to sputter damage from the projection arcs.

It has been suggested that the process might be used to produce the opposite effect: glass that transmits light but reflects heat. Such a material would have many applications in industrial processes involving high temperatures.

New uses for nylon

Nylon, delicate enough for the sheerest stocking, can also be one of the sturdiest of materials — as demonstrated by the fact that British manufacturers are using it to sheath boat bottoms. Combined with a vinyl plastic and glued to the planking, the nylon sheath not only restores seaworthiness to a leaky boat but also protects the wood from boring sea worms. Tested at a Nigerian port infested by the voracious teredo worm, a sheathed mahogany panel remained intact after twenty-two weeks in the water. If the nylonplastic gets cut or nicked, it can easily be patched. A British boatbuilder is offering elastic, abrasionresistant nylon bottoms — called Aquasheath — for his entire line of small craft.

A “printed" textile that is really dyed has been developed by the Bradford (England) Dyers Association Ltd. Under heat a nylon fabric which has been treated to resist dye is passed between two rollers, one of which bears an engraved pattern. The pattern is not visibly transferred to the cloth, but in the areas where the raised pattern applies pressure, a change in the molecules of the fabric takes place. When the invisibly embossed fabric is subsequently dyed, the pigment penetrates only the areas disturbed by the pattern. The final effect is very much like a print but with a slightly glazed or lacquered appearance.