As the scope of the work expanded we were pressed for room in the garage and Mr. Loomis purchased the Spencer Trask house, a huge stone mansion with a tower, like an English country house, perched on the summit of one of the foothills of the Ramapo Mountains in Tuxedo Park. This he transformed into a private laboratory de luxe, with rooms for guests or collaborators, a complete machine shop with mechanic and a dozen or more research rooms large and small. I moved my forty-foot spectrograph from East Hampton and installed it in the basement of the laboratory so that I could continue my spectroscopic work in a better environment. Mr. Loomis had a new tube made for the instrument, since there was no point in digging up the underground sewer pipes which had served formerly. He packed the tube in boiler felt with an arrangement for keeping the entire tube at a constant temperature, had a new and better camera made, installed motors, revolution counters, etc., for rotating the grating, which was housed in a small closet built around the brick pier on which it was mounted, and arranged other substitutions and gadgets, until I told him there was nothing left of my celebrated spectrograph but the forty feet. It had experienced a “reincarnation”, and required no pussycat as housemaid.
Loomis, who was anxious to meet some of the celebrated European physicists and visit their laboratories, asked Wood to go abroad with him. They made two trips together, one in the summer of 1926, the other in 1928. Going over on the Ile de France early in July, 1926, they were met at Plymouth by a Daimler in which they were driven to Hereford for a visit with Wood’s friend Thomas R. Merton, professor of physics at Oxford and now treasurer of the Royal Society. His estate bordered on the River Wye, and their arrival coincided with the salmon-fishing season. Merton had a fine private laboratory behind the house and some interesting experiments to show, but for once Loomis was excited over something other than physics. He waded in the Wye and landed a fifteen- pound salmon.
In Paris they had a fine time visiting laboratories, among them that of Dr. Jean Saidman, who was interested in the applications of ultraviolet light in the practice of medicine. He had much to say about Lumière Wood, which was the name the French had given it during the war. Wood says his own name is unfortunate since in translation it frequently becomes confused with the noun. An American consul in Paris once sent a report to the State Department that the French were finding important industrial applications for the light of a mercury arc passed through a “wooden screen”, his translation of “écran de Wood”. Dr. Saidman had all sorts of electrical apparatus, including an X-ray machine with a fluoroscope. Loomis had never witnessed the action of the human stomach, and the doctor politely offered to use Wood as a guinea pig. He was given a dose of barium carbonate, after which Loomis’s request was granted. Wood insisted on a mirror so that he could witness the process too.
They finally sailed for home on the Olympic.
Wood’s sensational and exciting circus methods of presenting scientific data had a queer and beautiful repercussion in 1926. The Franklin Institute in Philadelphia decided to sponsor a Christmas-week series of scientific lectures for children similar to those which Faraday had organized ninety years ago at the Royal Institution in London. Dr. Wood was invited to inaugurate the lectures with a talk on “Recreations with Radiations”.
He selected from all of the optical experiments with which he was acquainted a large assortment of the most spectacular, and in particular those which could be shown by projection, for many actual experiments can be shown in operation on a large white screen with an even greater brilliancy than that of motion pictures. From these he selected the ones which young people could understand, and arranged them in such order that a logical, continued story could be built up, beginning with the simpler ideas and going on gradually to the discussion of more difficult material. In particular, he worked out a method of projecting on the screen a much longer and more brilliant spectrum than had ever been shown before, so far as he knows. It was about a foot in width and ten feet long, the rainbow colors having a high degree of purity. With this as a background he showed numerous experiments on the absorption of light by various vapors, fluids, and solids, the bright-line emission spectra of metallic arcs, and related phenomena. A host of experiments with the brilliant-colored patterns produced by polarized light and some of his early experiments with sodium were also on the program, with the demonstration of its taking fire when thrown on water, and the story of the people who were scared to death by the “man who spit fire in a puddle”.
In the audience was nine-year-old Kern Dodge, grandson of Mrs. James Mapes Dodge and great-grandson of Mary Mapes Dodge, founder and long-time editor of St. Nicholas. The lecture had so filled this little boy with passionate joy and excitement that he went home in a sort of holy glow which set fire to his grandmother — whereupon she wrote out a check for $10,000 to endow the Christmas lectures for children and make them permanent.
Meanwhile, Wood’s scientific work was opening up new fields for study.
In the autumn of 1927 (Wood says) I made an astonishing discovery. During the spring before, I had observed that the fluorescence of mercury vapor excited by the blue light of the mercury arc was quite strongly polarized, a condition that is recognized by the appearance of dark bands crossing the luminous patch when viewed with a Nicol prism and quartz wedge. Returning to my laboratory in the fall, I started work again, but now was unable to repeat my observations. There was no trace of polarization whatever. The setup of apparatus, lamp, mercury tube, optical parts, had not been altered. I tried to think of some slight change that I had made and forgotten, but could think of nothing except that I had turned the table around so as to get one end away from the sink. What effect could that have? Obviously none; but how about the earth’s magnetic field? Fantastic idea! But I turned the table with all its load of apparatus back to its former position and lighted the mercury lamp. I looked through the polarization detector, and there were the black bands crossing the spot of green fluorescent light of the mercury vapor. Picking up a three-cornered file that was lying on the table I held it near the tube, and the dark fringes vanished. The file had been magnetized by some previous contact with a magnet, as were most of the files in my laboratory. Never before had so weak a magnetic field as that of the earth been found to affect any optical phenomenon, and work was immediately started in collaboration with Alexander Ellett, one of my best students. Our first problem, of course, was to neutralize the earth’s magnetic field in the vicinity of the apparatus, which was done by a pair of wire coils carrying a carefully adjusted current. The investigation occupied us for two years, for we found still more interesting and complicated effects with the vapor of sodium, in which case we were dealing with the simpler phenomenon of resonance radiation, instead of with fluorescence. These results opened up a wide field of new research on the effects of magnetism on light sources, and many papers appeared by other investigators.