GENERAL ARTICLES

Distiller of Rock

Dr. Lloyd Pidgeon’s process of getting magnesium for war service is a Canadian scientific ten-strike

IAN SCLANDERS January 1 1943
GENERAL ARTICLES

Distiller of Rock

Dr. Lloyd Pidgeon’s process of getting magnesium for war service is a Canadian scientific ten-strike

IAN SCLANDERS January 1 1943

Distiller of Rock

GENERAL ARTICLES

IAN SCLANDERS

Dr. Lloyd Pidgeon’s process of getting magnesium for war service is a Canadian scientific ten-strike

WHEN Lloyd Montgomery Pidgeon was a small boy he had a laboratory in the attic of the manse of Augustine Presbyterian Church in Winnipeg. All his experiments were odoriferous, the only difference between them being that some smelled worse than others. Acrid fumes would float downstairs, and his clergyman father would wrinkle his nostrils, look up from the sermon he was writing, and hoist the nearest window. His mother took things philosophically. She was quietly confident that more than a stench might some day come of her son's hobby-that he might even become a famous scientist. He did. Dr. Lloyd Montgomery Pidgeon of the National Research Council is the man whose process for distilling magnesium metal from rock is helping to win the war. His work still involves the occasional potent odor. When we were talking with him in his laboratory in Ottawa a while ago, there came a point at which we glanced at each other and broke out laughing. We laughed because we were both crying, and we

were crying because the emanations from ammonia react on your eyes in the same way as the emanations from freshly skinned onions. One of his young assistants had in progress a test in which ammonia was used. He reached for the nearest window—as his father had done so many times. Lloyd Pidgeon bears no resemblance whatever to the popular notion of what a scientist should look like. He is not tall and cadaverous, but of medium height and muscular build. Instead of being pale, his face is ruddy. His keen blue eyes, which twinkle with humor, are not concealed behind thick spectacles. His sandy hair is neatly trimmed and

his clothes are well tailored and carefully pressed. From his appearance he might be a successful business executive. He is thirty-nine years old. The last five of these thirty-nine years have been devoted to the study of that modern miracle metal, magnesium, which is only one quarter the weight of iron, and is needed so badly right now for aircraft construction, for incendiary bombs and for flares. His process for recovering it from dolomite, a crystalline limestone found in large quantities in many parts of the world—is being used in a $3,000,000 Government plant in a backwoods village in Ontario, and in five plants in the United States. On these plants the United Nations pin much of their hope of getting more magnesium in the shortest possible time. Because of these plants, and others, that car you are going to buy after the war will be a lighter and more efficient vehicle. Dr. Pidgeon would not be human if he wasn’t pleased that his process has become so important, but the praise which is being heaped on him hasn’t broken down his modesty. “There are a dozen fellows around the Research Council,” he will tell you, “who are working on projects that mean just as much or more. I was lucky. This just happened to come off. Some projects do; others don’t.” It irks him that people who should know quite a lot about magnesium ask him whether it isn’t dangerous. “If it is used as a structural material,” they ask, “isn’t it likely to catch fire?” This query arises, obviously, from the fact that Continued on page 22

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magnesium is an ingredient of photographic flash powder; that it’s the part of the incendiary bomb that does the dirty work; that it’s the part of the flare that gives off millions of candlepower.

To answer it Pidgeon will take you into his laboratory and light an oxy-gas torch. With this, in a matter of seconds, he will burn a hole in a board about an inch thick. Then he will turn the same torch on a block of magnesium and let it play there until you get tired of watching. It makes no mark.

“We could leave a flame that size on that block, and go out to lunch, and when we came back there still wouldn’t be any mark,” he will tell you. “But if you take magnesium in powder, or in small chips, it is different.”

He takes some small chips of the metal, places them on a brick, applies the torch. In jig time they are burning with a glare that is far too bright to watch.

“In a solid mass,” he explains, “there is no fire hazard from magnesium. The temperature at which it would ignite is so great that everything else would be burned first. But little pieces are not the same. They will catch fire.”

He looks at you with that everpresent gleam of humor in his eyes. The chips on the brick have burned themselves out; have left only a whitish powder.

“How do you feel today?” he asks.

“Fine,” you say.

“Well, if you didn’t I could take that powder that is on the brick and make you some milk of magnesia. It’s the same stuff. You just mix it with water.”

McNaughton Started It

THE story of Dr. Pidgeon’s research on magnesium goes back to a day in 1937 when Lieut.-General A. G. L. McNaughton, as president of the National Research Council, called a few of his staff into conference. Typically, he lost no time getting to the subject.

He had been thinking, he said, of magnesium. Magnesium was one of the most plentiful metals in the world. It was found in sea water— perhaps 5,000,000 or 6,000,000 tons of it in a cubic mile. There was more of it in the earth’s crust than of any other commercial metal but iron and aluminum. Niagara Falls, for instance, tumbled over dolomite, and dolomite was rich in magnesium. The mountain behind Hamilton was likewise rich in magnesium. The only trouble was that it was so difficult to recover.

Now, said General McNaughton, if somebody found an easier and better way of extracting magnesium it would be a wonderful thing. He looked around the group, singled out Pidgeon, asked how about it. And that was the beginning.

Dr. Pidgeon insists that there is nothing spectacular, nothing dramatic, to report about his subsequent research. He laughs if you ask him whether there wasn’t some turning

point, some incident that marked the dawn of discovery after groping in the dark, some flash of inspiration such as came to the inventor of the steam engine when he watched the lid of the kettle popping.

“No,” he will tell you, “we don’t discover things that way any more. If you start on a research problem, you will spend the first month or so in the library, reading.”

That’s what he did. He read all there was to read about magnesium from the time it was first isolated as a metal back in 1808 by Davy, the inventor of the miner’s lamp, right down to the present day. He studied all the methods of extraction.

Then he got busy in his laboratory putting these methods to the actual test. The most familiar of them was the electrolytic method, which uses brine deposits or sea water as its raw material. The brine, or sea water, is treated with chlorine to produce magnesium chloride. This, in turn, is fused to a red heat, and given a terrific jolt of electrical current which produces the metal.

Dr. Pidgeon found objections to electrolysis. For one thing, the equipment it required was costly; for another, it took tremendous quantities of power. On top of this it seemed doubtful whether it could be so improved that the price of magnesium could be brought down very much.

He discarded this process, which was the one used in Germany and the one used by Dow Chemical Company, the only magnesium producer in the United States at that time.

Finally he settled on ferrosilicon as an extracting agent. Ferrosilicon is made by reacting iron, sand and coke in an electric furnace. It has a greater affinity for oxygen than magnesia, and if you take the oxygen out of magnesia you get magnesium.

If ferrosilicon and magnesia are placed in a vacuum and heated to a high temperature, the ferrosilicon steals the oxygen and the metal is isolated.

Scientists were aware of this magic, but most of them thought of it as something which could not be done outside of the laboratory with any degree of success. Dr. Pidgeon believed it could.

At this stage there are details which must remain secret, but Dr. Pidgeon found ways to bring about distillation at lower temperatures that were supposed possible. Having done this, he devised a new kind of retort to make the ferrosilicon process commercially practicable. His developments boiled down to the fact that one of the most plentiful metals in the world, and one of the most amazing, could, on paper at any rate, be produced on a large scale at reasonable cost.

Proving It

BY 1940 he had carried his research about as far as he could in the laboratory stage. The proof, he knew, would require a pilot plant,

and pilot plants are outside the scope of the Research Council.

It was just about at this time that Robert Jowsey, of Toronto, veteran prospector and mine-maker, president of Bobjo Gold, descended on Ottawa looking for a job at which he could roll up his sleeves and do something extra for the war effort. He talked it over with his friend, George Bateman, controller of metals.

“Well,” said Bateman, “if somebody would start making magnesium, it would be one of the best things that ever happened.”

Jowsey set out to find how to make magnesium, met Pidgeon, was impressed. He next got in touch with a fellow gold mine president, Walter Segsworth, head of Moneta Porcupine and a mining engineer.

“If the country needs magnesium,” said Segsworth, “we’d better do something about it.”

They formed Dominion Magnesium Ltd. and entered into an agreement with the Research Council whereby they would put up funds for a pilot plant, and undertake certain other obligations, in return for rights to the Pidgeon process if it panned out.

Soon there was a busy little industry in the Research Council’s main building at Ottawa—a magnesium plant which turned out fifty pounds of metal daily and worked on three eight hour shifts. A few months of this, and the green light was showing for a major development.

Haley’s Corner, twelve miles from Renfrew, was chosen as the site. It perched on a deposit of pure dolomite, it was beside a railway line, and a block of electric power was available from a hydro unit on the near-by Ottawa River.

Dominion Magnesium, with Bobjo, Moneta Porcupine and Ventures sharing equally, was ready to finance a mill of a couple of tons capacity a day, but Ottawa, by this time, had decided a larger plant was needed, and that this could best be built with Government funds.

Today the plant at Haley’s Corner has a capacity of ten tons a day and the design is such that this output can be doubled in the future. Dominion Magnesium is looking after the management for the Government on a nonprofit, nonfee basis, and after the war will have the option of purchasing the property. .

Dr. Pidgeon still blinks when he visits Haley’s Corner and sees what grew out of his brain child.

“This time last year,” he told us, pointing, “there was nothing there but a farmer’s field.”

The field is now hidden by a sprawling metal and concrete building, from which the din of rock crushers echoes constantly. The quarry is in the back yard, so to speak, and the finished product comes out the front door.

There are ten furnaces in the plant, each with forty retorts, and there is a vacuum pump for each four retorts. So mechanized is everything that making magnesium is largely a button-pushing job, and a

minimum of skilled labor is necessary. Electric eyes, for instance, watch the temperature of the furnaces, and give the alarm if something goes out of kilter.

Most of the 200 employees are farmers drawn from the surrounding countryside. Most of them have had no.iprevious industrial training. Yet here they are—extracting metal from rock, and looking after the various phases of a process which, it was once thought, could only be done by scientists in a laboratory.

“It’s easier than baling hay,” one of them told us with a grin.

One advantage of a plant using the Pidgeon process is that the capital cost is low in relation to output— not one quarter of the cost of plants using some of the other methods of recovering the metal. Another is that such a unit can be built and placed in operation in a comparatively short period. Still another— and one which is proving important in the United States—is that the process requires less electricity than others—this when a growing power shortage faces the continent.

The magnesium content of the dolomite at Haley’s Corner runs about twelve per cent but there is some loss in the extraction and about eleven tons of rock has to be quarried to give one ton of pure magnesium.

Pidgeon In Private

LLOYD PIDGEON, son of Rev.

Dr. and Mrs. E. L. Pidgeon, of Montreal, and nephew of another well-known clergyman, Rev. Dr. G. C. Pidgeon, of Toronto, was born at Markham, Ontario.

He more or less made up for the odoriferous experiments of the attic by being able to fix things. Years before he stopped wearing short pants, there was nothing electrical, nothing mechanical, he couldn’t put in condition. And if his mother wanted a new kitchen shelf Lloyd could put it up in jig time.

He was handy enough to make himself such musical instruments as banjos and mandolins out of odds and ends, and for years one of his favorite pastimes was strumming a homemade banjo.

His present taste is for more serious brands of music and he has an elaborate electric gramophone, equipped with two loudspeakers, on which he plays the recordings of the Masters. He is very close to being concert stage calibre himself, at the piano, and nobody laughs when he sits down to play.

He has a charming wife, two children, and a bright dream of some day building himself the perfect sailboat.

“But I don’t know,” he shrugs, “when I’ll find time to get around to it.”

His university career was a blaze of scholarships, which carried him successively through the University of Manitoba, McGill, Oxford. After two years of research in England, made possible by the Ramsay Memorial Scholarship, he returned to

Canada, joined the staff of the National Research Council.

Since then he has had charge of several research projects. He’s the first to admit that he doesn’t ring the bell every time. Once he spent three years on something which, thus far, has amounted to nothing.

Dr. Pidgeon carries on a personal crusade against unnecessary weight in anything that moves on wheels. He hates it—thinks it is crazy that automobiles, trains, trucks and buses should be so heavy. He thinks the reason is a hangover from the Victorian epoch when the public got the idea firmly fixed in mind that light things were cheap things, that heavy things were good.

Pidgeon believes, and sincerely hopes, that this conception is now

fading, that men who build things to move on land are beginning to take a lesson from the men who build aircraft, and that the day of light metal alloys, in which magnesium will play such a part, is here at last. To get an inkling of what this means to your postwar car, just figure that a pound of magnesium will do the work of two or three pounds of steel.

One of the most encouraging signs Lloyd Pidgeon has seen lately was an advertisement in which the name “Zephyr” was applied to a crack train.

“Imagine,” he says, “referring to a train as a ‘zephyr’ a few years ago. A few years ago a locomotive was called an ‘iron horse’—and the emphasis was on the fact that it was heavy. People are learning.”