The DC area..........the Potomac river..........the below was taken from the piece about Langley.....the SI's 3rd secretary.................who petitioned congress for a telescope..........it ends with the Potomac river....


His first success came on May 6, 1896 when his Number 5 unpiloted model flew nearly 3/4 of a mile after a catapult launch from a boat on the Potomac River.^[6] The distance was ten times longer than any previous experiment with a heavier-than-air flying machine,^[7]demonstrating that stability and sufficient lift could be achieved in such craft.
On November 11 that year his Number 6 model flew more than 5,000 feet (1,500 m). In 1898, based on the success of his models, Langley received a War Department grant of $50,000 and $20,000 from the Smithsonian to develop a piloted airplane, which he called an "Aerodrome" (coined from Greek words roughly translated as "air runner"). Langley hiredCharles M. Manly (1876–1927) as engineer and test pilot. When Langley received word from his friend Octave Chanute of the Wright brothers' success with their 1902 glider, he attempted to meet the Wrights, but they politely evaded his request.
While the full-scale Aerodrome was being designed and built, the internal combustion enginewas contracted out to manufacturer Stephen Balzer (1864–1940). When he failed to produce an engine to the power and weight specifications, Manly finished the design. This engine had far more power than did the engine for the Wright brothers' first airplane—50 hp compared to 12 hp. The engine, mostly the technical work of men other than Langley, was probably the project's main contribution to aviation.^[8] The piloted machine had wire-braced tandem wings (one behind the other). It had a Pénaud tail for pitch and yaw control but no roll control, depending instead on the dihedral angle of the wings, as did the models, for maintaining roughly level flight.
In contrast to the Wright brothers' design of a controllable airplane that could fly against a strong wind and land on solid ground, Langley sought safety by practicing in calm air over the Potomac River.