Gravity‐observations in Peru and Colombia

In view of the present wide‐spread interest in Pan‐American affairs and the need, long recognized by geodesists, for base gravity‐stations in the equatorial belt of South America, a brief description of a recent cooperative gravity‐expedition in Peru and Colombia may be of interest. The earliest attempts at the measurements of gravity in South America were those of BOUGUER in the early part of the 18th Century. In his report, published in 1749, he describes the methods and results of his work in Peru and Ecuador in determining the figure of the Earth. BOUGUER determined the length of a filar‐suspension seconds pendulum at three points in Ecuador at elevations of 0, 9,400, and 15,600 feet. His results, of course, have no quantitative value.