Doctor Wood. Modern Wizard of the Laboratory: The Story of an American Small Boy Who Became the Most Daring and Original Experimental Physicist of Our Day-but Never Grew Up

Chapter Thirteen. Tuning in the War

While Wood was in Europe, in the autumn of 1913, he was invited to become a member of the Solvay Conference of the International Physical Institute which was meeting in Brussels. There were present about thirty eminent scientists, among them Einstein, Sir James Jeans, Lindeman, Rutherford, Rubens, Langevin — and Madame Curie. Madame Curie was the only woman, and at the opening of the congress she requested that the others refrain from smoking, as she disliked the smell of tobacco. Since the Institute had provided for each member a box of Havana cigars, her request was unpopular. At the second session, Wood (having meanwhile plotted with Professor Jeans) took out his pipe and lit it. Jeans followed suit, then one by one the other members helped themselves to cigars. Wood says Madame Curie rose, gathered her papers, and departed.

At about this time Wood bought by chance a little headphone radio — or “wireless receiving set” as it was called in those days. The day when they’d bring voices and music and be a fixture in every home was still in the far distant future. There was nothing to pick up from the Eiffel Tower station, or from anywhere, except Morse code. Nobody had receiving sets except cranks and scientists. How Wood acquired one, learned code, kept the gadget, brought it home to America, and “tuned in” privately on the World War before either the public or the newspapers got it can best be told in his own words.

We lived in an apartment on the Avenue Charles Floquet almost in the shadow of the Eiffel Tower. One day on the way to the Sorbonne I had passed an electric shop and saw a little galena headphone radio set in the window. There was a sign suggesting that you could use this set to listen to the Eiffel Tower radio station. So I thought it might be fun to learn code and I bought it.

An invalid friend of mine, a brother of S. S. McClure, who also lived at 14 Avenue Charles Floquet, worked with me, and in time we both learned to read Morse code. I bought him a set. We used to practice sending and receiving together. Mrs. McClure said she thought it saved his life. Signals came in from the Eiffel Tower with such strength that you could often see a spark between the cat whisker and the galena crystal on my receiving set.

When I got home — that must have been about the end of June, 1914 — I decided I might as well keep on with code practice if I didn’t want to forget it, and I installed a set at East Hampton, just about the same as the one I had in Paris, but with 150-foot antennas. Messages began coming in with good strength from Wellfleet on Cape Cod and from the German Telefunken station at Sayville, Long Island.

A few days before the outbreak of war, early in August, I was recording letters one at a time, as they came in, without realizing what it was all about, as is usual with novices. The message stopped suddenly, and I found I had written, “To all German ships at sea. England has declared war on Germany. Proceed at once to the nearest German port. On no account touch at French or English ports”. And then the Telefunken call letter signing off. This message was repeated at intervals during the day and night. I wondered why these messages were always in English. After war was declared, messages continued to come in from Telefunken, usually in English, addressed to the German cruisers Dresden and Karlsruhe, and this kept up for three or four weeks after the war had begun. We wondered then why the government permitted the sending of these messages from an American station. Later on the government put a stop to it.

There were a lot of messages in a strange code coming from Telefunken, with words like “Cuckoo Buffano” and “Ciro Teliko”. These words came in so frequently that I still remember them.

War news used to come in from Wellfleet and Telefunken (until it was closed down), and we got the latest news at East Hampton long before the newspapers reached us. People got into the habit of calling me up at all hours of the day and night — even drunks on the way home from dances would drive into our yard and wake me up shouting, “Hey, Prof, what’s the latest from Europe?”

Before the war was a week old Wood had written a letter to Lord Rayleigh, suggesting a method of destroying Zeppelins, on which public attention was focused at the moment. The attacking plane was to fly across the path of the Zeppelin a little ahead of her and drop small flaming steel darts, making a barrage of fire through which the airship would have to fly. The darts were to be threaded on a metal rod, which was to be drawn back by a mechanism that would release them at such intervals that the distance between them would be less than the width of the Zeppelin. This would make a hit certain and a single hit would mean the destruction of the airship by fire. This was essentially the mechanism now in use and referred to as “a stick of bombs”.

Early in November, 1914, he sent to the French, through Ambassador Jusserand, the suggestion that brombenzyl vapor or some similar compound be released in enormous quantities over twenty or more kilometers of the Western Front, at a time when the meteorological department could guarantee a west wind for several hours. The slightest whiff of this vapor causes a smarting pain in the eyes and a copious flow of tears. It is impossible to keep the eyes open, and, he pointed out, all that remained would be to advance and capture the weeping Germans, for a man who can’t see, can’t shoot. He pointed out that it would not violate the Hague convention, as no permanent injury resulted. This was six months before the Germans started gas warfare on too small a scale with chlorine, and gas masks were speedily developed. Tear gas came into general use later on.

Wood says the idea occurred to him suddenly as he was walking from a meeting of the National Academy with Professor Pupin and Dr. Welch, both of whom laughed at the idea and said a gas would soon be dissipated in the air. Wood replied that the odor of a fish-fertilizer factory fifteen miles from East Hampton was suffocating when the wind was right.

Later in the war, when he was in France, he discussed the question with the French gas people and reminded them that he had made this suggestion in 1914. They agreed with him that had they tried this on a twenty-five-kilometer front they probably would have broken through.

Shortly after America’s entry into the war, a meeting of the Naval Consulting Board was held in New York at the request of Admiral Sims. It consisted of a group of civilian scientists, engineers, and also naval officers, who were expected to think up useful ideas for the Navy. Sims was about to sail for England to discuss antisubmarine activities with the British Admiralty and wanted to arm himself with the latest suggestions. Dr. Wood, though not a member of the board, had been invited to participate.

During the exchange of ideas, Dr. Wood suggested that experiments be made with what are now called “blisters”. His idea was to have an outer shell of thin steel subdivided into a number of air-filled chambers, welded to the hull on the outside of warships, below the water line. A torpedo would explode on contact with the outer shell and the gases would expand into the air space and lose most of their destructive force. He said the idea could be tried at small cost on some condemned hull, substituting a bomb for the torpedo. Hudson Maxim, the explosive expert of the board, leaped to his feet and shouted, “Professor Wood is all wrong. The compartments should be filled with water instead of air”. This was perfect nonsense, and there were cries of “No, no”.

Sims rapped on the desk and said that further discussion would be a waste of time, as the British Admiralty had informed him no antitorpedo defense that involved the building of any structure whatsoever on the outside of the hull would be considered.

The English battleships and cruisers were equipped with “blisters” in the latter part of the war, and they are shown in many photographs of ships engaged in the present war. The principle of antitorpedo air pockets is now standard practice in naval construction, but they are incorporated within the hull. It seems strange that Sims knew nothing about them at the time of the meeting in New York, if they were already in use in the British Navy.

It was at this same meeting that Wood amazed them all — and shocked most of them purple — by suggesting that it might be a bright idea to train seals to chase submarines! They laughed, and some member tried to start a new topic. But Wood stood up and claimed the floor. He was a great scientist, and so they listened to him — and so help me God, the British Admiralty later tried it!

Wood began by pointing out that seals could be taught almost anything that dogs could. A collar with a steel wire attached to a large hollow ball of rubber painted scarlet and dragged along on the surface would enable the sub-chaser to follow the seal! A. G. Webster, professor of physics at Clark University, protested against wasting the board’s time with such a silly suggestion, and another member said you couldn’t train an animal to do anything it had no natural instinct for. Wood countered by asking, “How about fox hounds following a bag of anise seed?” and suggested that it would do no harm to consult a professional seal-trainer, who would be the one best qualified to decide whether the suggestion was worth trying.

Sims took the idea over to London, and within a month the Admiralty was conducting experiments with seals, on a lake in Wales, admitting subsequently that the idea had come through the United States naval attaché in London. They found that seals could be trained to hunt out and follow the sound of a submarine’s propeller, and perhaps the odors from the oil and exhausts. The experiments were commenced with an electrical “buzzer”, and the hungry seal was rewarded with a fresh fish as soon as he located or followed it. In experiments with their own submarines, they had what Dr. Wood characterized as “considerable success”.

The “water bloodhounds” never trailed or caught any German U-boats, however, and as a would-be honest biographer I am compelled to say that the “considerable success” attributed by Dr. Wood to his trained seals was not a determinate factor in marine warfare. The seals had been muzzled to discourage independent fishing expeditions of their own, but one of the difficulties encountered was that they had a tendency to run off after schools of herring anyway — just as the bloodhound abandons Eliza or a convict to go off chasing rabbits. Other difficulties were that the seals not infrequently followed wrong ships, and that the floats attached to their collars could not be made large enough to be clearly visible at great distances or in fogs. The seals did learn to trail oil, and learned for that matter to trail the sound of screw propellers, and therefore proved Dr. Wood’s contention — but the whole business leaves me with the conviction that the idea was even more “screwy” than the sterns of the U-boats. One thing of importance did result from these fantastic experiments. They proved that the seals could hear perfectly well when swimming at full speed under water, and this discovery was responsible for an improvement in the performance of the hydrophones or “listening trumpets” which were towed under water and picked up propeller sounds. The noises made by the rush of water across the trumpet’s mouth drowned out fainter sounds, and it had been necessary to slow down or stop the chaser for listening purposes. By studying the contours of the seal’s ears and applying their design to the ears of the hydrophones, their performance was greatly improved.

It was after Wood had his major’s commission and was working with the Bureau of Inventions in Paris, in co-operation with all the Allies, that he conceived what has since been variously called the “spider shell”, the “spaghetti shell”, the “piano-wire shell”, and the “parachute shell”. It perhaps happily combines, as I see it, the two paradoxical categories of his war inventions. It is certainly fantastic, yet it must be pragmatically sound, since the British were reported to be reviving and using it in the air defense of London in 1940 — and international press services were attributing its origin to “Professor R. W. Wood, Johns Hopkins University physicist”.

Here’s what Wood says about it.

In discussing defense against hostile aircraft with a number of officers of the French air force at one of the aerodromes, in November, 1917, I suggested that experiments be made with shells containing a coil of steel piano wire — the shells to be constructed like the “parachute bomb” in pyrotechnics. One end of the coil was to be attached to the base of the shell and the other to a small silk parachute packed in the nose. On explosion the base would be driven downward, unwinding the coil of wire, while the parachute would open and drift along with the long strand of wire dangling below, like the spider that spins a long thread into the breeze, and then floats away carried by his thread. I also suggested this at one of the meetings of the Bureau of Inventions in Paris, calling it the “spider shell”, but nothing appears to have been done with the idea at the time. After the war I alluded to it in a number of public lectures on the relation of scientific research to warfare. Several paper patents appear to have been taken out by various parties in the interval between the two world wars. According to press accounts the wire strands used in the present war were not provided with parachutes and would fall rapidly.

During all this hectic time, while Wood was inventing war gadgets and later, when we went in, pulling every possible human wire to get into uniform and actual service “over there”, he wasn’t neglecting his purely scientific work.

In the early part of the summer of 1916, he was busy in East Hampton developing a new filter for the photography of the planets by ultraviolet light, which he planned to use with the great sixty-inch reflecting telescope of the Mount Wilson Observatory in California. The filter consisted of a cell made by covering the ends of a short section cut from a square glass bottle with plates of “uriol” glass. This cell was filled with bromine vapor, which he had found to be transparent to ultraviolet light but opaque to all other rays capable of acting on the photographic plate.

In late September Wood went with his wife and daughter Margaret to San Francisco, their first visit with the grandparents since before the earthquake in 1906. Wood immediately went down to Pasadena and was quartered in the so- called “Monastery”, the sleeping quarters of the observatory staff on Mount Wilson. The sixty-inch telescope was assigned to him for four evenings, and, to his delight, he found Harlow Shapley, who had assisted him in Princeton, now a member of the staff and ready to help him again. The bromine cell was mounted on a brass frame directly in front of the plateholder, which covered an aperture in the side of the great tube near the top, the huge mirror of “silver on glass” being at the bottom of the tube. Photographs of Jupiter and Saturn were made with infrared, yellow, violet, and ultraviolet light, the latter showing an equatorial belt on Saturn that had never been seen before, the cause of which gave rise to considerable discussion among astrophysicists. It was finally decided to be a circular cloud of very fine dust that bordered the “ring” on its inner edge.

As this research neared its end, a “terrible” tragedy occurred.

We had cleaned and charged the cell with fresh bromine vapor (Wood says), leaving as usual a drop or two of the liquid to make up the loss due to its slow combination with the beeswax cement. One of us had clamped it in position, and the great telescope was slowly swung into its nearly vertical position. Suddenly there was a crash like that made by a glass bottle shattered on a cement floor. “Good God”, we both (I think) gasped. “The bromine cell on the silver mirror”. I leaned over the edge of the tube and looked down. Sure enough, on the great circular shining silver surface, five feet in diameter and twenty-five feet below me, there was a large irregular black splotch, some eighteen inches across. There was nothing that could be done at the moment, and I was relieved to see that the spot was not spreading, which indicated the bromine had all been used up. But had the glass surface been damaged? That was the question that caused a sinking feeling in the pit of my stomach. Shapley said that it was his fault, as he believed he had attached the cell, but I insisted (I hope) that it was mine, as I felt sure I had done it. However, it turned out all right: the glass mirror was not damaged, they were planning to resilver it anyway in a couple of weeks, and the amount of silver removed had not caused enough loss of light to interfere with the program arranged for the intervening time. We felt better when told by the director that worse things than this had happened. One of their mechanics had once let a small monkey wrench fall on the mirror, which made a large nick in the surface.

Returning to Baltimore late in October, he started a new line of investigation with Professor Okano, a Japanese scientist who had been sent to work with him. They investigated what is known as the “ionizing potential” of sodium vapor, which had never been determined. Defined in words, they were to determine the lowest voltage that would cause sodium vapor to glow or emit light in a vacuum tube. The final result was interesting, though they did not feel sure of it until a number of sources of error had been discovered and conquered. A sodium lamp could be operated with an electric potential of only 1.5 volts on its terminals or by one dry cell, provided free electrons were present. Wood had, in 1910, in collaboration with R. H. Galt, one of his students, studied the spectra of the electrical discharge in dense sodium vapor, and been struck by the overpowering brilliancy of the yellow light in some cases. “It was like looking at the sun through a yellow glass”, he says. He had dreamed of sodium lamps, naturally, but at the time there was no way of preparing a glass tube or bulb that would not blacken and become opaque after a few minutes’ exposure to the corrosive vapor. It was this circumstance that had caused Lord Kelvin to ask, “Have you succeeded yet in taming sodium vapor?” Modern sodium lamps are of course the latest development for street lighting.