Chris Cox is preparing to be become one of the men who put up and maintain the power lines that satisfy the huge demand for electricity in the USA. He's a trainee linesman in California. Working with high voltages is extremely dangerous. He has to be super fit and totally focused on the job and, of course, he needs a good head for heights because for much of the time he will be working up 60 feet poles. A strong set of boots with sharp metal crampons and a thick leather belt that allows him to lean out from the pole at 30 degrees are all he needs to get to the top. Cox is part of a growing generation of young people who are rejecting the idea of going to university in favour of a hand-on approach to furthering their skills