Experiments by Stringfellow.
The next man to test an apparatus with superposed surfaces was Mr.
Stringfellow, who, becoming much impressed with Mr. Wenham's proposal,
produced a largish model at the exhibition of the Aeronautical Society
in 1868. It consisted of three superposed surfaces aggregating
28 square feet and a tail of 8 square feet more. The weight was under
12 pounds and it was driven by a central propeller actuated by a steam
engine overestimated at one-third of a horsepower. It ran suspended to a
wire on its trials but failed of free flight, in consequence of
defective equilibrium. This apparatus has since been rebuilt and is now
in the National Museum of the Smithsonian Institution at Washington.
