The Ugly American and the Soviets struggled for preeminence in the Third World through proxies in Latin America, Africa, and Asia. In the Middle East, the US feared the spread of Communism starting in Egypt and attempted to secure the region's most populous and politically powerful country for the West by guarantees of funding for construction of the Aswan Dam but it was eventually the Soviets who prevailed. Soviet diplomatic and political successes in the Third World left the West worried about losing one country after another to Communism according to the domino theory evoked by President Dwight D. Eisenhower. It was in
Aswan the summer solstice, a vertical staff cast no shadow. They noted that the sun's disc was reflected in a well at noon. This statement is only approximately correct; at the summer solstice, the shadow was only of the staff, and so could scarcely be discerned, and the northern limb of the Sun's disc would be nearly vertical. However, Eratosthenes used this information together with measurements of the shadow length on the solstice at Alexandria to perform the first known calculation of the circumference of the Earth. The Nile is nearly wide above Aswan. From this frontier town to the northern