Tetrahedral Kites!

Although best known for developing the practical telephone — for which he became the first, in 1876, to secure a US patent — the Scottish-born inventor Alexander Graham Bell is also noted for his work in aerodynamics, a rather more photogenic endeavour perhaps, as evidenced by the wonderful imagery documenting his experiments with tetrahedral kites. The series of photographs depict Bell and his colleagues demonstrating and testing out a number of different kite designs, all based upon the tetrahedral structure, to whose pyramid-shaped cells Bell was drawn as they could share joints and spars and so crucially lessen the weight-to-surface area ratio.

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Bell began his experiments with tetrahedral box kites in 1898, eventually developing elaborate structures comprised of multiple compound tetrahedral kites covered in maroon silk, constructed with the aim of being to carry a human through the air. Named Cygnet I, II, and III (for they took off from water) these enormous tetrahedral beings were flown both unmanned and manned during a five year period from 1907 until 1912.

The delightful images below have mainly been sourced from three places: Bell’s own private journals, which meticulously log his progress not only with text but also with numerous photographs pasted into the pages (from 1903–104); a couple of articles (from 1903 and 1907) in the National Geographic Magazine; and the Bulletin of his Aerial Experiment Association, which he led from its beginning in 1907 until it disbanded in 1909.

There are so many photos, I just grabbed one at random, The Public Domain has oodles of photos, and links to all the sources!