A series of six lectures reworked for publication surveys civil engineering from ancient to modern times, outlining hydraulic and structural achievements in Mesopotamia and Egypt, Roman roads, aqueducts, harbors, and practical rules of ancient practice. It then follows the evolution of bridges and contemporary theory, treating stresses, materials, construction methods, and mechanical appliances. The closing sections compare proposed interoceanic canal routes across the Central American isthmus, notably Nicaragua and Panama, evaluating topography, alignment, water supply, lock versus sea-level schemes, and constructability using photographic illustrations and technical analysis.