Izaak Maurits Kolthoff (1894–1993) has been described as the father of modern analytical chemistry for his research and teaching that transformed the ways by which scientists separate, identify, and quantify chemical substances. Once a collection of empirical recipes and prescriptions, the field of analytical chemistry is today an essential branch of chemistry built upon solid theoretical principles and experimental techniques, the basis of which was formed over the course of Kolthoff’s nearly 80-year career.
1930s
DayGlo fluorescent pigments, a new class of pigments based on fluorescent dyes and polymeric materials, were developed between the 1930s and 1950s by scientists at Switzer Brothers, Inc. (now Day-Glo Color Corp.). These pigments absorb various light frequencies (visible and invisible to the human eye) and reemit them, producing intense visible colors that appear to glow, even in daylight.
When Georgia chemist Charles Holmes Herty found a way to make quality paper from pine trees in 1932, he also founded an industry that brought much-needed jobs to the depression-crippled south. Paper producers had deemed the plentiful pine too gummy—until Herty's Savannah Pulp and Paper Laboratory wrote a new chapter in the ancient craft inspired by insects who built paper nests while dinosaurs roamed the earth. At its root, however, the papermaking process remained the same: the bonding of cellulose, a polymer whose long chains support plant cell walls.
Albert Szent-Györgyi (1893-1986), biochemist, pioneered the study of biological oxidation mechanisms during the 1920s. Between 1930 and 1936, while a Professor at Szeged University, he proved that hexuronic acid, which he had previously isolated, is identical with vitamin C and that it could be extracted in kilogram quantities from paprika.
"It remains today one of the great bridge engineering accomplishments for railway and highway bridges built in the country."
- Historic American Engineering Record, Southeast Regional Office, National Park Service, U.S. Department of the Interior, 2005
With the dawn of the automobile age at the beginning of the Twentieth Century, the entire nation started to demand better roads. In the 1910s, motorists and businessmen in Utah became aware of the possibilities of tourism as a business. Soon the state of Utah and the federal government responded with a decades-long program to improve transportation to and within Zion National Park.
Several factors argued for a road through Zion National Park:
One morning in April 1938, 27-year-old DuPont chemist Roy J. Plunkett cracked open the valve of a pressurized canister containing tetrafluoroethylene (TFE) gas in preparation for an experiment. Much to his irritation, the canister that he had filled the night before appeared to be empty. His assignment had been to find a replacement for the refrigerant Freon 114, on which Frigidaire currently held a monopoly. To conduct his scheduled experiment that morning, he needed to release some TFE into a heated chamber and then spray in hydrochloric acid.
In 1933 the 68-year-old inventor Niels Christensen finally tackled a problem that had bothered him throughout his long career in hydraulics. His elegant and simple solution—the O-ring—would become such a ubiquitous part of so many technologies that it is present by the dozens in every home and car, and applied to everything from fountain pens and soap dispensers to hydraulic presses and bomb-bay doors.
Early in 1924, 34-year-old Edwin Armstrong returned to Columbia University, the scene 11 years earlier of his breakthrough invention of the regenerative circuit, while only a sophomore. His device had amplified radio waves a thousandfold and made radio practical. This time he had set his sights on eliminating static from radio, a problem most felt was insoluble. “Static, like the poor, will always be with us,” declared the chief engineer of AT&T.
Serial doodler, drafter, and brainstormer, New Hampshire–born Earl S. Tupper was an inventor obsessed with improving everyday household objects. His rough sketches, scrawled with a fountain pen over rapidly yellowing notebook paper, include an eyebrow shield to allow more precise penciling; adjustable glasses; hairpins that wouldn’t fall out; and garter hooks that remained fastened. “My purpose in life [is] to take each thing as I find it and . . . see how I can improve it,” he wrote.