Alexander Graham Bell

What, THE Alexander Graham Bell?

Yes, most famous for the invention of the telephone, Alexander Graham Bell was an Inventor and originator in very many areas.  As well as telephones he was interested in flight, structural engineering, the deaf and water craft, amongst many other things.

Throughout his life Bell invented many items, starting with a device to clean Wheat which he invented at the age of 11, and then moving on through such items as air conditioning (he used air blown past blocks of ice), devices to sort punched cards, storage of information using magnetic media (such as we now use for audio cassettes and floppy disks).

As well as inventing physical items, Bell, driven by a history of deafness in his family, devised a phonetic alphabet to help the deaf learn to speak.  Bell also founded the first ever school for the deaf.

Bell is most famous, however for developing three items. The one everyone knows about is the Telephone of course, that being first demonstrated in 1876.  He also developed the hydrofoil, successfully setting the world speed record of 70.86mph in 1919.  The third major invention of his sits between these two, and is the one we are interested in - the Tetrahedron kite.

So why did he develop the Tetrahedron kite?

The development of the kites were driven by the competition to produce manned, powered flight.  By 1891 Bell had realised that the most stable platform to base an aircraft on was a kite, and he began experimenting with this.

One of the classic problems with kites is that of scaling them up - as a kite gets larger the structure needed to support the kite needs to be progressively stronger, and thus much heavier. 

Starting from a triangular box kite - a good, stable starting point, Bell soon realised that he could remove some of the framework, and still end up with a stable kite.  Eventually he came down to a four triangular-sided design that had considerable advantages over the triangular box design - the most important of these being structural integrity; the triangle is a very stable shape - just try squashing one.

Once Bell had developed the basic tetrahedron unit he spotted it's potential in structures, and designed buildings, bridges and towers using the same principal.  One such tower was built looking down over the Bras D'Or lakes near to Bells home.