Down in the seven seas more optical cables carry the major share of ocean-crossing traffic, and they are multiplying fast. Amazingly, Victorian glories such as Lord Kelvin's Atlantic cable and Isambard Kingdom Brunel's paddle-wheel leviathan, the Great Eastern, are still evoked by today's hot news. FLAG has eight segments between landfalls. First it passes the Straits of Gibraltar to touch Spain, then eastward past Scylla and Charybdis to Egypt, down the Red Sea to Bombay to curve wide around the tip of India, then across the narrow isthmus in Thailand, achieving its terminal in Japan via Hong Kong and Korea.
Strong branches go off to the United Arab Emirates, Malaysia and China.
Nor is FLAG alone. It was physicist John Tyndall in 1854 who first admired the guiding of light by curved jets of water. Today's fibers guide perfectly. They are precisely layered cylinders of very pure silica, a tiny core clad by a coating of slightly lower refraction. The first task in the long development of optical fiber was to give it an incredible clarity.