Paul Alexander contracted polio in 1952 when he was six, leaving him paralysed from the neck down.

In 1952, when he became ill, doctors in his hometown of Dallas operated on him, saving his life. But polio meant his body was no longer able to breathe on his own.

The answer was to place him in a so-called iron lung - a metal cylinder enclosing his body up to his neck.

The lung, which he called his “old iron horse”, allowed him to breathe. Bellows sucked air out of the cylinder, forcing his lungs to expand and take in air. When the air was let back in, the same process in reverse made his lungs deflate.

He would go on to earn a law degree - and practise law - as well as publish a memoir.