1940s

In 1941, near Palouse, Washington, Raymond A. Hanson conceived of a self-leveling mechanism for hillside combines. On the steep hills in the Pacific Northwest, leveling is necessary to save grain because of the gravity grain separation mechanism. Before the Hanson invention, manual leveling required a person to stand on the combine platform and adjust the machine to the lay of the land - a hot, tedious job. The grain-saving attributes of Hanson's invention were probably more important than the labor saving, although both were valuable.

In the mid 1930's, the USDA Soil Conservation Service (SCS) realized the importance of hydrologic processes on agricultural fields and watersheds and determining their impact on soil erosion, floods, water resources, and the agricultural economy. In response, the SCS Hydrologic Division established experimental watersheds in Coshocton, Ohio, Hastings, Nebraska, and Riesel, Texas, and operated them until 1954 when the watersheds were transferred to the newly created Agricultural Research Service (ARS). 

The first commercial circulating fluid bed reactor, PCLA #1 (Powdered Catalyst Louisiana), went on stream on May 25, 1942, in the Baton Rouge Refinery of the Standard Oil Company of New Jersey (now ExxonMobil Corporation). This first use of powdered catalysts in continuous operation allowed the efficient cracking of heavy gas oils to meet the growing demand for high-octane fuels. Today, fluid bed reactors are in use worldwide for the manufacture of fuels, chemical intermediates and plastics.

The plaque commemorating the development reads:

Developed by Rohm and Haas in the 1940s, water-based acrylic emulsion technology filled a need for easy-to-use household paints for a growing suburban population in the United States following World War II. This aqueous technology required less preparation to use, was easier to clean up, had less odor, and performed better than or equal to paints made with solvents. It was also a leap forward in acrylic chemistry.

Taken together, the 1940 and 1950 Tacoma Narrows bridges mark a significant turning point in the design of long-span suspension bridges. The original 1940 structure was designed with one of the shallowest and narrowest stiffening elements of any long-span suspension bridge yet built. The structure failed dramatically in a rather moderate 42 mph windstorm on 7 November 1940, only four months after opening for traffic.

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In 1888, George Eastman created the Kodak camera, the first camera designed to use roll film. The camera's simplicity and user friendly mechanism revolutionized amateur snapshot photography and in 1892, he founded the Eastman Kodak Company, in Rochester, New York.

On December 23, 1947, in the Bell Telephone Laboratories at Murray Hill, New Jersey, physicists John Bardeen and Walter Brattain spoke over the world’s first transistor-amplified telephone circuit, a quarter-inch-tall device composed of a thin strip of gold foil sliced in two in order to create two metal contacts over a crystal of germanium. Their success was the culmination of eight years of research conducted alongside their team leader, 37-year old William B. Shockley, and triggered a wave of new electronics.

In early 1945 Laurence Marshall contemplated the imminent financial ruin of his company. Raytheon had enjoyed a lucrative business supplying the U.S. military with magnetrons, electron tubes that generated microwaves, a key component in the nascent technology of radar and the detection of enemy airplanes. But World War II seemed likely to end soon, and with it Raytheon’s lucrative military contracts. Raytheon needed to come up with something it could sell to civilians.

It is difficult to recall a time when doctors and patients had trouble tracking the presence of glucose and other substances in urine and blood. Lack of sufficient measurement tools made it difficult to manage a host of diseases, including diabetes as well as other metabolic diseases and kidney and liver conditions. Today, self-management of these diseases is an easier process because of the development of diagnostic test strips by Alfred and Helen Free and their research team at Miles Laboratories.

The text of the plaque commemorating the development reads: