Making elevators safe

Alexander Miles did not invent the elevator, but he made it safe. The African-American inventor and entrepreneur patented his electric elevator with automatically closing doors on October 11th, 1887. Early elevators had been used several hundred years BC, powered by human or animal muscle power, and occasionally water power. Before Miles filed his patent, the elevators of his day were steam powered, and had doors that had to be opened and closed manually. Sometimes people forgot and were injured; sometimes people stepped into empty lift shafts and fell hundreds of feet.

Miles improved their safety with mechanisms that closed off access when the lift was moving, and closed the doors automatically before the cage could move. His lifts were electric, and the mechanisms he devised continue to influence modern elevator design. The story is that he was inspired when he was travelling with his daughter in an elevator whose doors had been left open. He attached a flexible belt to his cage design so that it opened and closed doors with levers and rollers when it passed over drums positioned appropriately.

Born in Ohio in 1838, when many black people in the US were slaves, he’d shown his talents by creating and marketing hair care products. He progressed from being a barber to becoming a prosperous businessman. His United Brotherhood life insurance company was designed to give black people insurance they had no access to otherwise. He was the first black member of the Duluth Chamber of Commerce. He died in 1917, and was posthumously inducted into the National Inventors Hall of Fame in 2007.

Modern elevator design begins with Alexander Miles, but it certainly does not end there. Several engineering research teams are working on the technology that could be used to construct the most ambitious engineering project ever undertaken, the construction of an elevator that could take people and cargo into space. Situated at the equator, it would have an overhead base in geostationary orbit, 22,500 miles above the Earth’s surface, where TV satellites are located. A cable would connect the fixed point on the rotating Earth to the fixed point in a rotating orbit, with a huge counterweight above that point to keep it stable. Elevator cages would ride up and down that cable, possibly powered by a nuclear reactor at its base.

The space elevator would enable people and cargo to reach space without the huge expenditure of rocket fuel currently required, and not subject to the forces that currently play upon them. The concept of a tower reaching up to a geosynchronous orbit was first published in 1895 by the Russian space physicist Konstantin Tsiolkovsky. Sir Arthur C Clarke, who pioneered the use of TV satellites in a 1945 paper in Practical Wireless, has researched and written about space elevators, most notably in his 1979 novel “The Fountains of Paradise.”

No materials yet devised have the ensile strength and lightness to enable such a cable to be built, although carbon nanotubes are being investigated as a possibility. The space elevator would be a stupendous project, dwarfing anything that humans have achieved before, but if humanity is to become a spacefaring species, a breakthrough of this nature might be needed. No doubt it will be opposed by people who want us to “live more simply,” and by those who think the money would be better spent on social housing and equality awareness seminars. They will tell us that we don’t need to go into space, but we do. If we build it, I hope they will name one of its carriages after Alexander Miles, as an appropriate tribute to his inventive mind.