Erected 1968, commemorating the 100th Anniversary of discovery of helium in the gaseous atmosphere surrounding the sun. (The discovery of traces of helium on earth was first announced in 1895.) The four time columns are filled with books, documents, and various artifacts that will tell future generations about life in 1968. After the time columns were filled, the caps were welded on and the contents sealed in a helium atmosphere. In twenty-five, fifty, one-hundred, and one thousand years from the time of filling, the four individual columns are to be opened. Helium is an element which occurs in commercial volume in natural gas produced since 1918 from wells in the Texas Panhandle. In 1929 the first of several helium processing plants began operations near Amarillo. Large quantities of helium extracted from natural gas are stored underground northwest of Amarillo, and will provide a valuable source of supply for many years. Once used only in lighter-than-air craft, helium now serves vital needs in industry, science, and the nation's military and space programs. (1968)