1930-1949

San Antonio's River Walk, a catalyst for abundant commercial and tourism enterprise, is generally regarded by cities and urban planners throughout the world as a prototype for the development of urban riverfront sites. The River Walk's success, however, would not have been possible without a series of flood-control and architecture projects completed in the first half of the 20th century that relied heavily on civil-engineering expertise. 

When Arnold Beckman, a professor of analytical chemistry at the California Institute of Technology, was asked to devise a way to measure acidity in citrus fruit, the resulting “acidometer” revolutionized chemical instrumentation. The innovative features of the pH meter, including its use of integrated electronic technology and all-in-one design, were the basis for subsequent modern instrumentation developed by Beckman and his company.

The plaque commemorating the development reads:

Steroid chemists often refer to the 1930s as the Decade of the Sex Hormones, when the molecular structures of certain sex hormones were determined and first introduced to medical practice as drugs. Russell Marker achieved the first practical synthesis of the pregnancy hormone, progesterone, by what now is known as the "Marker Degradation." Produced from starting material in a species of Mexican yam, Marker’s progesterone eventually became the preferred precursor in the industrial preparation of the anti-inflammatory drug cortisone.