Not all the towers along a transmission line are identical. Look closely at a tower where the line makes a sharp turn and you will likely find it is wider and beefier than other towers along the route. The added strength and weight are needed to resist the unbalanced pull of the conductors, which might overturn an ordinary tower. These special towers are called deviation or angle towers.
The transmission-line tower everybody knows is an Erector Set latticework of steel girders and diagonal braces. The techniques for designing and building these towers are the same ones used in constructing steel bridge trusses or crane booms. The individual pieces can be made cheaply from rolled steel and then bolted together on the site. This last point is more important than it might seem: transporting a fully assembled tower 100 feet tall is an awkward and expensive business.
Ruskin's Seven Lamps of Architecture provided seven guides, or 'lamps', for the troubled craftsman, guides for anyone who works directly on material things. These seven are:
The lamp of sacrifice: The willingness to do something well for its own sake.
The lamp of truth: The truth that 'breaks and rents continually'; Ruskin's embrace of difficulty, resistance, and ambiguity.
The lamp of power: Tempered power, guided standards other than blind will.
The lamp of beauty: Which for Ruskin is found more in the detail, the ornament—hand-sized beauty—than in the large design.
The lamp of life: Life equating with struggle and energy, death with deadly perfection.
The lamp of memory: The guidance provided by the time before machinery ruled.
The lamp of obedience: Obedience to the example set by a master's practice rather than by his particular works; otherwise put, strive to be like Stradivari but do not seek to copy his particular violins.