Since 1948, over 11,000 dams and associated conservation practices in more than 2,000 watershed projects encompassing 160 million acres in 47 states have been constructed as a part of the USDA Small Watershed Program. These projects have improved the quality of life and the environment in rural communities by protecting people's lives and property, conserving soil and water resources, reducing flooding, providing economic development, recreation, and water supplies, enhancing water quality, and improving wetlands and wildlife habitat.
A Crucial Step In The Evolution Of Modern Animal Agriculture Was The Development Of Mechanical Ventilation Methods For Animal Housing. Air Inlets Are Pivotal To Good Ventilation. In 1948 William F. Millier, Working At Cornell University Under The Direction Of Professor Clesson Turner, Tested And Published The Concept Of The Slotted Inlet. Professor Turner And Others At Cornell University Subsequently Continued To Develop Slotted Inlet Systems And Systematize Design Methods.
The convenient dry-copying process for printed pages is among the truly revolutionary inventions of the century. In 1937 Chester Carlson, a New York patent attorney, developed the concept of applying an electrostatic charge on a plate coated with a photoconductive material. On November 22, 1938, Carlson dusted powder dyed with evergreen spores across an exposed plate and transferred the imprint to the surface of a paper.
The use of heat pumps for the heating and cooling of the Commonwealth Building, initiated in 1948, was a pioneering achievement in the western hemisphere. The theoretical conception of the heat pump was described in a neglected book, published in 1824 and written by a young French army officer, Sadi Carnot. Its practical application on a large scale is attributable to designers J. Donald Kroeker and Ray C. Chewning, building engineer Charles E. Graham, and architect Pietro Belluschi.