Xerxes' Pontoon Bridges Xerxes' Pontoon Bridges Xerxes' Pontoon Bridges were constructed in 480 BC during the second Persian invasion of Greece upon the order of Xerxes I of Persia for the purpose of Xerxes’ army to traverse the Hellespont (the present day Dardanelles) from Asia into Thrace, then also controlled by Persia (in the European part of modern Turkey). The bridges were described by the ancient Greek historian Herodotus in his "Histories", but little other evidence confirms Herodotus' story in this respect. Most modern historians accept the building of the bridges as such, but practically all details related by Herodotus are subject to
All-dielectric self-supporting cable No metal wires are used in an ADSS cable. Optical fibers are either supported in loose buffer tubes, or arranged in a ribbon configuration. To prevent strain on the fibers, most types provide the fibres with excess slack length compared to the length of the supporting member. Several designs of cable are used. In one type, small plastic tubes each containing up to eight fibers are filled with a gel compound, and stranded around plastic rods. The hydrocarbon gel compound prevents water from wicking along the length of the cable. The inner structure is wrapped with polyester tapes and encased