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

Not much came of these lunar experiments (says Wood), chiefly because of climatic conditions. Dew formed on the mirrors, the clock did not drive very steadily, and there were innumerable mosquitoes, who came from all directions to see what was going on. So later in the autumn through the courtesy of Professor H. N. Russell of Princeton University, I was given an opportunity of mounting my sixteen-inch mirror at the Princeton Observatory. Professor Harlow Shapley, now director of the Harvard Observatory, was then a fellow in astronomy at Princeton, and he assisted me in handling the telescope and making the exposures.

We made photographs of the full moon by orange, violet, and ultraviolet rays, the latter bringing out the dark deposit bordering the lunar crater Aristarchus with great distinctness, while the orange-ray picture showed no trace of it. Experiments showed that when a gray volcanic rock was treated at one spot by blowing a jet of sulphur vapor against it, a thin deposit of sulphur crystals was formed which was invisible to the eye but came out black in a photograph made with ultraviolet rays. It therefore seemed probable that an extensive deposit of sulphur had been found on the moon’s surface by the new photographic technique.

The plates obtained through the ray filters could be studied to advantage by the methods employed in the three-color process of color photography. The negative taken through the ultraviolet screen was printed on a gelatin film and stained blue, the violet and orange pictures being rendered in red and yellow respectively. The three films when superposed resulted in a very fine color photograph which brought out the differences in the reflecting power of the different dark areas on the moon in a very striking manner. The prevailing tone of the darker portions of the lunar surface was olive green, but certain spots came out with an orange tone and others with a decided purple color. The dark spot near Aristarchus came out deep blue, as was to be expected.

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INFRARED LANDSCAPE: A 1911 photograph made by Wood of a summer landscape in Sicily – the earliest landscape photograph with infrared light ever made. Wood also pioneered in ultraviolet-light photography.

PEGOUD UPSIDE DOWN: Wood pirouettes in the snows of St.Moritz, in the constume he designed that won first prize at the fancy dress ball.

In 1911 Wood also continued his researches with mercury vapor and detected resonance radiation in the ultraviolet region, analogous to the sodium vapor resonance at the yellow lines. The thing of greatest interest was the invention of what he termed a resonance lamp.