"In 1958, Felix Candela completed his most significant work, the Los Manantiales Restaurant shell, in Xochimilco, Mexico City. ...[He] was taking a risk... The form was original, unexplored, and impossible to analyze precisely. Candela’s career, however, habitually flew in the face of precise analysis. In his first acclaimed shell, the Cosmic Ray Pavilion of the University of Mexico City, he also designed an unprecedented form, using almost no calculation... Candela’s subsequent designs relied increasingly on structural understanding and practical experience. As a designer-contractor, he had the unique responsibility of building his own solutions. By closely observing his buildings, and using smaller projects to test new ideas, he developed an acute sense of concrete shell behavior."