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

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.