Figures & Tables
Scientists have long been trained to build on the successes or failures of their predecessors, their teachers, and their fellows largely through scientific associations and their publications. Such societies range from small, local ones to huge organizations with membership drawn from over 100 countries. The oldest and most prestigious for geophysicists is the Royal Society, given both its name and charter by Britain’s King Charles II back in 1660. The Royal Astronomical Society, chartered in 1820, has also had a marked interest in geophysical matters, even to the extent of publishing a Geophysical Journal, because the earth is very much a part of the planetary system. Within the United States, the prestigious National Academy of Sciences (NAS) was started as an ally of government at the initiative of President Abraham Lincoln who asked the scientific community in 1863 for technical assistance with the war effort. Geophysical societies per se did not appear until the early 1900s. As a result of the great San Francisco earthquake, the Seismological Society of America (SSA) was formed in 1906. The International Union of Geodesy and Geophysics (IUGG) came into being in 1911, while its U.S. interface, the American Geophysical Union (AGU), was finally organized in 1919. The field of exploration geophysics lagged even further, with the Society of Exploration Geophysicists not being incorporated until 1930.
Long before the advent of scientific societies, perceptive men had been contending with the physical forces of nature. Aristotle (384–322 BC) compiled the first known geophysical treatise, the Meteorologica, less than half of which pertained to weather matters—the remainder dealt with oceanography, astronomy, and meteors (also called shooting stars). Formal seismic instrumentation appeared as early as A.D. 132 when Chang Heng set up a seismoscope in China that not only indicated that an earthquake had occurred but also the direction of the first motion. However, man’s formal knowledge of the physics of the earth did not change much from the time of Aristotle until late in the European Renaissance, when the fertile mind of Leonardo da Vinci (1452–1519) initiated new thinking on this subject, as he did in so many others. Early in the 16th century, he studied, for example, the tides of the Euxine (Black) and Caspian Seas, as well as the mechanics and inherent dangers of rock slippage along a geological fault near Florence, Italy. He also deduced that Alpine rocks were at one time submerged for he found embedded sea shell fossils.