so that maintenance and repair workers can climb the pole to work on the lines. In the United States, such steps have been determined to be a public hazard and are no longer allowed on new poles. Linemen may use climbing spikes called gaffs to ascend wooden poles without steps on them. In the UK, boots fitted with steel loops that go around the pole (known as "Scandinavian Climbers") are also used for climbing poles. In the US, linemen use bucket trucks for the vast majority of poles that are accessible by vehicle. Dead-end poles The poles at the end of a straight section of utility line where the line ends or angles off in another direction are called dead-end poles in the United States. Elsewhere they may be referred to as anchor or termination poles. These must carry the lateral tension of the long straight sections of wire. They are usually made with heavier construction. The power lines are attached to the pole by horizontal strain insulators, either placed on crossarms (which are either doubled, tripled, or replaced with a steel crossarm, to provide more resistance to the tension forces) or attached directly to the pole itself. Dead-end and other poles that support lateral loads have guy-wires to support them. The guys always have strain insulators inserted in their length to prevent any high voltages caused by electrical faults from reaching the lower portion of the cable that is accessible by the public. In populated areas, guy wires are often encased in a yellow plastic or wood tube with reflectors attached to their lower end, so that they can be seen more easily, reducing the chance of people and animals walking into them or vehicles crashing into them. Another means of providing support for lateral loads is a push brace pole, a second shorter pole that is attached to the side of the first and runs at an angle to the ground. If there is no space for a lateral support, a stronger pole, e.g. a construction of concrete or iron, is used. History The system of suspending telegraph wires from poles with ceramic insulators was invented and patented by British telegraph pioneer William Fothergill Cooke. Cooke was the driving force in establishing the electrical telegraph on a commercial basis. With Charles Wheatstone he invented the Cooke and Wheatstone telegraph and founded the world's first telegraph company, the Electric