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Rain Bird Impact Drive Sprinkler Head
Society: ASABE Main Category: Agricultural & Biological Sub Category: Era: 1930-1939 DateCreated: 1933 Rain Bird corporate office Azusa State: CA Zip: 91702 Country: USA Website: Creator: Englehardt, Orton

The Rain Bird horizontal action impact drive sprinkler head was invented in 1933 by Orton Englehardt, a citrus grower and native of Glendora. The design offered slow rotation and uniform watering, benefits long sought by local irrigators. Clement M. LaFetra, a friend of Englehardt, urged early patent application. A patent was awarded on December 18, 1933. Englehardt, with no entrepreneurial aspirations, assigned all rights to LaFetra and his wife Mary Elizabeth. Production began in the LaFetra family barn on October 13, 1935.

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Noble Blade Cultivator
Society: ASABE Main Category: Agricultural & Biological Sub Category: Era: 1930-1939 DateCreated: 1937 Nobleford Centennial Park Nobleford State: Zip: AB T0L 1S0 Country: Canada Website: Creator: Noble, Charles S.

In the 1930's thousands of acres of land were rendered unproductive through wind erosion because of drought, tillage, and dust mulch farming practices. Charles S. Noble, of Nobleford, Alberta, invented a cultivator that sheared stubble and weeds below the ground surface, leaving residue on the soil to reduce evaporation and prevent erosion by strong Alberta winds. The Noble Blade Cultivator was patented in 1937. The Noble family subsequently developed a variety of straight and V-blade cultivators.

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Anhydrous Ammonia Application Technology
Society: ASABE Main Category: Agricultural & Biological Sub Category: Chemical Era: 1930-1939 DateCreated: 1932 Delta Research and Extension Center Stoneville State: MS Zip: 38776 Country: USA Website: Creator: Edwards, Felix, Smith, J. O., Andrews, W. B.

In 1932, J. O. Smith, Agricultural Engineer at Delta Branch Experiment Station in Stoneville, MS, attached a small anhydrous ammonia cylinder to a plow in such a manner that the NH3 was released in the soil.  The plow, a Georgia Stock, was pulled by a gray mule named Ike.  This was the first known use of anhydrous ammonia as a soil-applied crop fertilizer.  The crude apparatus and the anhydrous ammonia it applied provided a much needed source of nitrogen for the otherwise rich alluvial soils of the Mississippi Delta. 

Image Credit: Courtesy Flickr/thirteenofclubs (CC BY-SA 2.0) Image Caption: Anhydrous Ammonia is one of the cheapest forms of nitrogen fertilizer available on the market. However because it is such a hazardous material and is difficult to apply, many farmers choose to hire third party businesses to store and apply the fertilizer. Era_date_from:
Mellon Institute of Industrial Research,
Society: ACS Main Category: Chemical Sub Category: Education Era: 1930-1939 DateCreated: 1937 4400 Fifth Ave Pittsburgh State: PA Zip: Country: USA Website: Creator:

Prior to its merger with the Carnegie Institute of Technology in 1967 to form Carnegie Mellon University, the nonprofit Mellon Institute for Industrial Research was a major, independent research corporation dedicated to promoting applied research for industry and educating scientific researchers for the benefit of society as a whole. The Institute educated hundreds of fellows for careers in industrial research and helped to sell the very idea of research to manufacturers.

Image Credit: Courtesy Wikicommons/Piotrus (CC BY-SA 3.0) Image Caption: Mellon Institute, CMU Era_date_from:
Society: Main Category: Sub Category: Era: DateCreated: State: Zip: Country: Website: Creator:

At 5:04:40 on Saturday morning, May 26, 1934, the first diesel-powered, stainless-steel, streamlined train pulled out of Union Station, Denver, on a dawn-to-dusk race for Chicago. Called the Zephyr, it had been delivered to the Chicago, Burlington & Quincy Railroad in Philadelphia just six weeks earlier and had traveled west in a series of short trips. To reach Chicago before sunset, it had to cover 1,015 miles nonstop in less than fourteen hours.

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Society: IEEE Main Category: Electric Sub Category: Era: 1930-1939 DateCreated: 1930-1945 Tokyo Institute of Technology Nikaho State: Zip: Country: Japan Website:,_1930-1945 Creator: Takei, Takeshi
Dr. Takeshi Takei, the professor at the Tokyo Institute of Technology, discovered that composite oxides containing zinc and iron have distinguished magnetic properties. In 1930, Prof. Takei submitted a paper on his work to Japanese Electro-chemical Society and also presented a paper at 57th General Meeting of American Electrochemical Society in St. Louis. That same year, Prof. Takei applied a patent for his discovery, which was granted in 1932(Japan PAT-98844). Tokyo Denki Kagaku Kogyo (now TDK Corporation) was founded in 1935 to commercialize this newly invented ferrite cores.
Image Credit: Courtesy Tokyo Institute of Technology Image Caption: A replica of the early soft-ferrite core. Era_date_from: 1930
Hydromatic Propeller
Society: ASME Main Category: Aerospace & Aviation Sub Category: Aerospace Era: 1930-1939 DateCreated: 1938 New England Air Museum
Bradley Intl. Airport
Windsor Locks State: CT Zip: 06096 Country: USA Website:, Creator: Hamilton Standard

Rapid development of aircraft design in the 1930s required many related innovations, including propeller design. The hydromatic propeller by Hamilton Standard marked a significant advance over the counterweight-type, controllable pitch propeller. The first test flight of the prototype took place in 1938: the public demonstration was made by a United Air Lines DC-3 over New York City on April 6, 1938. It played a distinguished role in allied combat aircraft in World War II.

Image Credit: Courtesy ASME Image Caption: An early example of propeller innovations, including variable-pitch control and feathering capability. Era_date_from: 1938
Link C-3 Flight Trainer
Society: ASME Main Category: Aerospace & Aviation Sub Category: Aviation Era: 1930-1939 DateCreated: 1935 Roberson Museum and Science Center

Binghamton State: NY Zip: 13905 Country: USA Website: Creator: Link, Edwin

During the 1920s, Edwin A. Link was employed in his father's organ building and repair business. He obtained his pilot's license in 1927 and became convinced that a mechanical device could be built as an inexpensive method to teach basic piloting. Link received three patents on his flight trainer (No. 1,825,462, March 12, 1930; No. 2,244,464, June 3, 1941; and No. 2,358,016, Sept. 12, 1944).

Image Credit: Courtesy Wikipedia/Tony Speer Image Caption: An early flight simulator representative of the first truly effective mechanical device used to simulate actual flight processes. Era_date_from: 1935
White River Concrete Arch Bridge
Society: ASCE Main Category: Civil Sub Category: Bridges Era: 1930-1939 DateCreated: 1930 White River Cotter State: AR Zip: 72626 Country: USA Website: Creator: Marsh, James Barney

When this 1,850-foot concrete-arch highway bridge was built on the White River in a remote region of northern Arkansas - prior to the construction of upriver, flood-control dams - flash floods occurred frequently, sometimes causing the water to rise as much as one foot per hour. Construction under these conditions presented a clear danger, so project managers specified both a design and an innovative construction method appropriate to the problem of building across a perilous stretch of unpredictable river.

Image Credit: Courtesy Flickr/jaystout (CC BY 2.0) Image Caption: White River Concrete Arch Bridge Era_date_from: 1930
Waldo-Hancock Suspension Bridge
Society: ASCE Main Category: Civil Sub Category: Bridges Era: 1930-1939 DateCreated: 1931 Penobscot River Stockton Springs State: ME Zip: E 04981 Country: USA Website: Creator: Steinman, David

Designed by David B. Steinman, of Robinson & Steinman, New York City, the Waldo-Hancock suspension Bridge is a significant example of Steinman's work. David Steinman is considered among the most important suspension bridge designers of the 20th century. He earned an engineering degree from Columbia University in 1909 and went on to apprentice with Gustav Lindenthal, then at work on New York's Hell Gate Bridge. In the 1920's, Steinman emerged as an outstanding and innovative suspension bridge designer.

Image Credit: Courtesy Flickr/Justin Russell (CC BY 2.0) Image Caption: Waldo-Hancock Suspension Bridge Era_date_from: 1931
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