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 Nine. High Lights, High Jinks

Early in 1905 Wood finished the monumental work on physical optics which was destined to make him an outstanding authority on all subjects connected with light. The manuscript of Physical Optics was in the hands of Macmillan, destined to appear officially in the autumn of the same year, but it was due in the meantime for the oddest “prepublication” in the history of scientific books. Here’s what apparently happened.

In 1905 the Wood family spent the summer again in France. Just as they were leaving Paris for Brittany, an enormous bundle of galley proofs arrived from New York. Wood dumped them in the Darracq, to be corrected and mailed en route. The Macmillan Company claims with truth the first official publication, but it seems to have appeared previously, “serially” and uncopyrighted, dipped into with amazement by tourists, in hotel privies and backhouses scattered all over Normandy and Brittany. Not caring to bother with the two sets of duplicates of the galley proofs, he had tossed them into hotel wastebaskets, as he mailed the corrected set back, in installments, to New York. Motoring to Paris over the same route two months later, they found large sheafs of Physical Optics hung on nails as toilet paper in many of the inns where they had previously stopped.

Weird extracurricular excursions, alarms, and adventures kept occurring to Wood and his brain children when they returned to Baltimore, despite the steady progress of his serious scientific work. One of these occurred when a wealthy Baltimore engineer by the name of Otto Luyties conceived what may have been the first practical idea in the world for experiment with helicopters and invited the by now famous Johns Hopkins professor to aid him in matters of theory. Since Luyties was paying all the expenses, Wood agreed cheerfully to lend all the “theory” he could.

At that period (says Wood) Lord Rayleigh’s collected works were my Bible. He had shown by calculations that the weight that could be raised by an engine or motor of given horsepower could be increased indefinitely by increasing the diameter of the airscrew. I verified these predictions by mounting a large electric motor, with its axis vertical, on a platform scales and attaching airscrews (or propellers of thin wood) of different diameters directly to the projecting axis of the motor. The blades of the largest one employed barely cleared the walls of the room, and registered the highest lifting force on the scales. Small models were made, driven by rubber bands, which rose in the air and sailed off in horizontal flight.

Presently Luyties built one whose horizontal propeller looked like a windmill about twenty feet in diameter. It had a twenty-five horsepower motor, and in May, 1907, they took it out to Sparrows Point for a trial flight.

Wood said, “Who’s going up?”

Luyties said, “Not me. I’ve engaged a parachute jumper who will do anything for fifty dollars”.

The propellers were of canvas like the sails of a Dutch windmill or the jib on a yacht. Just then the parachute jumper came up and Wood said, “Are you really going to do this?”

“Sure”, the parachute jumper said, “for a hundred and fifty dollars I’d do a bomb ascension!”

Wood wanted to know what that was, and the jumper said: “I go up in a balloon, drop with a parachute, and have a string about forty feet long below my legs on which a bottle of gunpowder explodes. Once the string got tangled up, the bottle exploded between my legs — and look at my scars! I will still do a bomb ascension for a hundred and fifty dollars, so why shouldn’t I do this for fifty?”

The helicopter was on the wagon scales, and the parachute jumper was on the helicopter. The engine started. The sails filled out. Wood says it was lovely. It looked like a merry-go- round. It finally trembled, lifted a hundred pounds of its own weight off the scales, but remained otherwise stationary. Wood says the parachute jumper got his fifty dollars — but he doesn’t feel that he himself was quite so well treated. While it was about to go up, it was Luyties’s machine and Wood was only a “theoretical adviser”. But when it came out in the Baltimore papers next morning, it was Wood’s machine that had failed to rise from the ground.

Wood also participated in many of the more serious, sometimes successful and sometimes tragic aviation experiments in those pioneer days. One of these was with his friend Lieutenant Thomas Selfridge, who was subsequently killed in the ill-fated flight at Fort Myer with Orville Wright, in the autumn of 1908 — just a week after Selfridge had been a house guest of the Woods at their summer place on Long Island. On Selfridge’s invitation, Wood had made a trip with him to Hammonds- port, New York, where Glenn Curtiss, Selfridge, and McCurdy had been financed by Alexander Graham Bell to develop a power-driven plane.

They had just finished constructing the June Bug, he says, and were making short daily flights in a straight line. They hadn’t been able yet to make circular flights, principally because the June Bug's engine, which was then air-cooled, over heated too quickly. Wood, remembering his own laboratory expedients for cooling off red-hot sodium-vapor tubes, told them that if they packed the cylinders in cotton wool drenched with water, the engine would keep cool longer. Curtiss thought the idea was absurd, even as a temporary expedient, and vetoed it. Wood, always insistent when he believes he’s right in matters of that sort, proved his point conclusively with tests made on the engine of Curtiss’s six-cylinder racing motorcycle in the laboratory there. Before they were able to use this method with the June Bug, a water-cooling system had been worked out, making the longer circular flights possible. Wood, who had flown in Lilienthal’s glider, wanted at this time to make a solo flight in the June Bug, but the plane was “wavy” and dangerous, and Curtiss wasn’t wanting any needless dead celebrities strewn around his field.

Another of his extracurricular — but in this case completely successful — scientific stunts during this period was the invention of the so-called “fish-eye” camera. Long years before, while poking around under water in the primitive diving helmet he’d made with a wooden pail, he had suddenly said to himself, “I wonder what the world looks like to a fish..”.

In discussing refraction in his lectures on optics, he had always taken up the view which the submerged swimmer gets when his eyes are directed upward to the surface of still water, which appears as if covered by a dark ceiling with a circular sky-lit window directly overhead. The entire sky from horizon to horizon is compressed into this window and all objects surrounding the pond, trees, houses, fishermen, etc., should appear around the edge of this circle. The water is, however, always rippling from the disturbance due to the swimmer’s descent, and the eye does not focus well when submerged, so it is next to impossible to see any trace of what should be a sharp, though somewhat distorted, picture embracing an angular aperture of 180°. Wood had looked for this in vain with his wooden-bucket diving helmet at Cataumet many years before, forgetting at the time that the rays from the horizon, which are refracted down at a steep angle on striking the surface of the water, are bent back into their original direction when they enter the air inside of the helmet, through its glass window.

It occurred to him, however, during one of his lectures, that by immersing a camera — plate, lens and all — in water and waiting for the ripples to subside before making the exposure, a sharp photograph of the phenomenon might be obtained. After a few preliminary experiments with a tin lard pail furnished with a horizontal opaque diaphragm and filled with water, he constructed what he named the fish-eye camera. A brass box was made measuring five by six by two inches, into which a photographic plate could be slipped through a slot in the side, which was then sealed by a rubber gasket. The box was then filled with water through a small hole, closed by a screw cap. The optical system consisted of a small square of plate glass backed by an opaque film of silver covered with varnish, in the center of which he made a minute circular window, by scratching off the opaque film. This plate was cemented over a small hole at the center of one side of this box, glass side up. This was covered with a hinged lid, which served as a lens cap for making the exposure. The surface of the pond was represented in this case by the outer surface of the glass plate, the pinhole aperture forming the image on a photographic plate which was immersed in the water with which the box was filled. This was in effect a camera with the equivalent of a lens of a working angle of 180°, and it could be pointed in any direction, up, down, or sidewise.

As his first subject he selected an overhead trestle bridge, which carried the streetcars across the railroad yards at the Monument Street crossing. This should give a good idea of how an overhead bridge appears to a fish in a quiet stream below it. Placing the sinister-looking black box on the ground, he was annoyed to find himself surrounded by an interested group of colored children, who had followed him to see what it was all about. As they would of course ruin the picture, he told them to clear out, an order which was greeted by giggles. An exposure of a minute would be required, and Wood suddenly had an inspiration. Lighting a match, he held it against the side of the box, shouting, “Beat it, or you’ll be blown sky high”, and raising the lid of the box, he hurried away. The crowd scattered in all directions, and at the end of a minute he returned, closed the lid, and strolled back to his laboratory.

While the scientific significance of the fish-eye camera was given to the world in the British Philosophical Magazine and other technical journals, our Literary Digest and the Illustrated London News took it up from the point of view of the fish — particularly the fish in aquariums who seem generally to stare just as much at us as we do at them — and probably think we’re just as queer.

In 1908, the Woods bought the old Miller farmstead, with its pre-Revolutionary house and huge barn and its remaining five acres of land, near the seashore in East Hampton, Long Island, far out toward Montauk Point. There are deeds of conveyance dating back to 1771, and the hand-hewn beam structure of the buildings indicates that they too may date back that far.

Wood transformed the immense barn and its adjacent cowshed at East Hampton into a summer laboratory. Both here and at Johns Hopkins, he was absorbedly at work throughout these years — despite diversions and digressions — with new experiments, discoveries, and inventions. He later invented and installed beneath the cowshed the mercury telescope which made a world-wide sensation; he also built the largest spectroscope (or spectroscopic camera) in the world, and cleaned it of spiderwebs with the unwilling co-operation of the family cat[8]. He took aerial photographs by sending a camera up on a kite and releasing the shutter with ordinary firecracker punk. He made the further steps which were to mark a high light in his career by resuming and improving the photography of the moon with invisible ultraviolet light, which he had begun back in 1903.

He also took terrestrial time out, as it were, to debunk the complicated theory evolved by purely academic physicists to account for the high temperatures obtained in conservatories and greenhouses, which had crept into nearly all textbooks that mentioned the matter at all. It is well known that glass is quite opaque to the greater part of the sun’s spectrum beyond the red, that is, the region of longer wave lengths. The old theory considered that the visible light and shorter heat waves passed through the glass and heated the ground. The ground, thus heated, was supposed to give out radiation of such long wave length that it could not pass through the glass and was therefore trapped.

Wood’s theory was merely this: the glass house lets in the heat rays, which warm the ground, which in turn warms the air. This warm air is shut in by the house, instead of rising to the clouds as it does in the open. If you leave the doors of a greenhouse open, what becomes of the old theory?

He proved his case by the following very simple experiment. Constructing two enclosures of black cardboard, he covered one with a glass plate and the other with a plate of transparent rock salt. The bulb of a thermometer was inserted in each enclosure, and the apparatus exposed to sunlight. The temperature rose to 130° Fahrenheit, practically the same in each bulb. The rock salt is transparent to practically all of the heat radiations concerned, and on the old theory the enclosure covered by this material should not show the greenhouse effect, that is, there would be no trapping of radiation and the temperature of the enclosure would be much less.

In December, 1908, Wood was called upon to give a public lecture dealing largely with color and its application to paintings (the word “color” here refers to light rather than to pigments). Partly as a demonstration to enliven this lecture and partly because he thought it might have some use in stage lighting, he had worked out an optical method for the intensification of the color of paintings. Wood had occupied himself with the painting of landscapes in oil for some time as a diversion and had frequently noticed that a spot of sunlight, coming through chinks in the foliage and falling upon a green meadow in the picture, had produced a pleasing effect.

It occurred to him that if this enhancement of the illumination could be applied to all of the high lights in the picture in proper proportion, there would probably be a startling increase in the brilliancy of the picture. The whitest paint is only about sixty times as bright as the darkest paint ever employed by artists, whereas the ratio of intensity of sunlight on a white building to the deep shadow of a doorway may be as much as a thousand to one.

He found a way of intensifying the light contrasts in paintings by photographing the original painting, preparing a lantern slide from the negative, and projecting it with a lantern placed at such a distance as to secure exact registration of the image on the original. In this way, a powerful illumination was thrown on the high lights and a feeble light on the shadows, with all the intermediate gradations correctly controlled. The effect in a dark room is quite startling — a landscape fairly glows with sunlight. After viewing it for a few minutes, if the lights in the room are turned up and the lantern turned off, the picture looks as if it had not been dusted for years. The audience was amused when a large portrait of a prominent trustee was illuminated in this way, and Wood found that by joggling the projecting lantern the pupils of the portrait’s eyes glanced rapidly back and forth from right to left in a most lifelike manner.

Wood saw a possible practical use of this discovery in connection with stage effects, in which the painted backdrop could be illuminated by a lantern in the gallery which projected upon it a photograph made in a similar manner. This, he thought, should be particularly effective in sets which were supposed to be drenched in sunlight.

Wood’s most important work, however, continued to center around the optical investigation of sodium vapor. Examining the absorption spectrum of sodium vapor in the ultraviolet, he succeeded in increasing the number of lines of the principal spectral series from the eight previously known to fifty. It was, and still is, the longest spectral series known. This discovery was later cited by Niels Bohr as a beautiful proof of his new theory of atomic radiation, for which he received the Nobel prize. Another experiment of Wood’s at the same time that was also important in the new theories of radiation was his demonstration that the fluorescent light emitted by sodium vapor (and potassium and iodine vapor as well) was polarized — that is, a large percentage of the light vibrated in a single plane. At the same time, Wood was working with one of his students, H. W. Springsteen, on magnetic effects on polarized light. Corbino, an Italian physicist, some years previously had noted that by placing a sodium flame between the poles of an electric magnet and passing a beam of polarized white light through it, the plane of polarization of some of the yellow light was rotated several degrees. Wood and Springsteen, working with metallic sodium heated in a glass tube instead of a sodium flame, obtained rotations as great as 14° in the yellow region, and discovered marked traces of rotation in other regions of the spectrum. Wood was to continue this work for a number of years, with more powerful magnets and improved technique, obtaining rotations as great as 1,440° or four complete revolutions, results of great value to the theoretical physicists.

In the summer of 1909 Mars was in opposition, and all the astronomers were on tiptoe. Wood took out the six-inch lens of his big spectroscope at East Hampton and mounted it on a block of cement on the lawn in front of his laboratory door. A silvered mirror reflected the light of the red planet through the lens and thence to an eyepiece forty feet away, at the back of the dark laboratory, where he viewed the magnified image of the planet while lying comfortably on the floor on an old mattress.

During this same summer he resumed his experiments on photographing the moon in ultraviolet light, and showed the possibility of getting some notion of the nature of the rocky surface of the moon by photography with light confined to selected regions of the spectrum. His first paper on the subject was communicated to the Royal Astronomical Society of Great Britain by Sir Robert Ball, the Astronomer Royal, and published in the Monthly Notices of the Society, from which I quote:

The preliminary experiments were made at my summer laboratory at East Hampton, Long Island, N. Y., with an improvised instrument made out of odds and ends. A thin film of silver, opaque to all visible light, transmits quite freely ultra-violet light of wavelength 3000, but these rays will not go through glass, consequently a lens made of quartz was necessary. A photographic telescope was made of a three-inch silvered quartz lens of six-foot focus mounted over one end of a piece of galvanized iron stove-pipe, with a plate- holder at the opposite end. This was lashed to a five-foot astronomical telescope which served for following the moon, during the three-minute exposure which was necessary. Both were attached to an equatorial mounting made of an old bicycle frame embedded in a block of cement, the steering axis pointing to the pole star. A slow motion enabled me to make exposures of several minutes if necessary. A more detailed description of this instrument will be found in the English Mechanic for November 12, 1909.

I had discovered an extensive deposit of some material which is dark in ultra-violet light, close to the crater Aristarchus. This deposit shows scarcely at all in the pictures made in yellow light, while it is nearly black in pictures made by light confined to the ultra-violet range around wave-length 3000.

Parallel experiments made in the laboratory showed that many substances which are white in ordinary light are jet black when photographed with these very short waves. Chinese white (zinc oxide) and most white garden flowers are good examples. These white flowers, if growing on a snow-bank, would be nearly invisible, and would not appear in photographs made in the usual way, but would be clearly brought out in pictures made with the quartz lens and the silver film.

In this same year, 1909, the American Academy of Arts and Sciences gave Wood the American gold Rumford Medal for his work on the optical properties of metallic vapors, and Clark University, at Worcester, Massachusetts, conferred on him the degree of LL.D., in company with other distinguished American and European scientists, including Freud and Vol- terra, the celebrated Italian mathematician. Wood has never taken his honors any too seriously, and here’s what he says, recollecting the occasion.

After the rather heavy and solemn ceremonies were over Professor Webster, head of the Physics Department, invited us to his house for cheese and beer. As things dragged a bit, Webster asked me to show them a celebrated parlor trick I’d invented when a student at Johns Hopkins.

Lying on the floor one evening and watching the inverted face of one of the graduate students who was talking while standing up, I had been intrigued by the ludicrous expressions of the talking mouth when viewed upside down. In my imagination I pictured eyes and nose on the chin to complete a small face engaged in animated conversation. It was screamingly funny, and I at once got out my water colors and painted the eyes and nose in the proper position with respect to the mouth, laid a mirror flat on a table, seated myself before it, and covered the upper part of my face with a black veil, transparent enough to see through. By holding a mirror in my hand well out in front of me, I could see the reflected image of the little face right side up in the large mirror, and I recited Jabberwocky with many grimaces to observe the effect. It was a great success, and had been exhibited on many occasions to small but enthusiastic audiences seated in front of the mirror. After the performance in Webster’s parlor was over and the laughter had died down, dear old Volterra came up to Webster and, shrugging his shoulders and holding his hands palms up in a gesture of despair, said plaintively, “C’est plus gai ici qu'en Europe!”

Despite metallic vapors, gold medals, hard work, and what- have-you, the Woods had been keeping things pretty gay too in summertimes at East Hampton. Believe it or not, our professor learned to dance the bunny hug and turkey trot, and is credited with a howling wisecrack when someone asked if he wasn’t afraid of treading on the feet of the young matron who was giving him a lesson in the. then new “close-up” clinches. “How can I?” he demanded, “when her feet are always behind me?"

Costume parties, barn dances, amateur theatricals followed one another in dizzy succession every summer, and each gave Wood a chance to demonstrate his ingenuity and high spirits. The “face on the chin” trick was elaborated into a vaudeville act by projecting it in color by a homemade lantern onto a huge white head made from a properly compressed pillow. (Ziegfeld later experimented with the idea.) But Wood probably got most fun out of an “aeroplane flight” that was the climax of a vaudeville show that the Woods put on in the famous barn. Here is Wood’s account of it.

The feature of the evening was announced as an aeroplane flight from the roof of the barn. An iron wire had been fastened from a pole on the top of the barn, descending at a small angle all the way across the wide lawn to the front gate of the house. From this was suspended on two small steel roller trolleys a huge Weather Bureau box kite used in meteorological investigations, which had been sent to me as an aid in kite photography experiments. At the appointed hour I appeared on the lawn clothed in some ridiculous aviation suit, goggles, beard, etc. Introduced by a barker as Bleriot, the first man to cross the English Channel by air, I mounted a ladder behind the barn, climbed up over the roof, and hoisted the box kite over the ridge pole, with a straw man, clothed as I was, suspended below it. Lighting the stick of red fire between the fore and aft wings and giving the machine a push, I sank back out of sight behind the ridge pole. Away it went with a streak of red smoke behind and the trolley wheels adding their scream to the screams of the women which rose when the whole contraption — man, machine, and red fire — crashed into a bush by the gate.

Towards the end of this crowded year of 1909, Columbia University wrote to Wood asking him if he would care to be an Adams Research Fellow of Columbia. There was a fund left by Edward Dean Adams of New York as a memorial to his son, Ernest Kempton Adams, the income to be devoted to maintenance of a research fellow and the publication and distribution of the results of the research.

All that Professor Wood would have to do in return for the honorarium was to permit the publication of his papers by Columbia University in the form of a book, for the years during which he held the fellowship.

Wood accepted it and held the fellowship for three years. It enabled him to take a sabbatical in 1910-11, and again in 1913-14, Johns Hopkins University paying him half salary during the years which he spent abroad.