other buildings were woven on the court looms. It was said of Abbas I’s unparalleled achievements in art and architecture, “Isfahan is half the world.”

The commencement date of the Royal Mosque is uncertain. Some sources give 1590, a little early in the context of other urban development, and others claim that Abbas I laid the first stone in spring 1611. Ali Reza, the calligrapher responsible for the inscriptions in the building, dated the main entrance in 1616. Although Abbas put great pressure on his architect Ostad Abu’l-Qasim and his team of workmen, the mosque was incomplete when the Shah died in 1628 at the age of seventy. It is probable that work was still going on two years after that. The beautiful building certainly set a precedent, for elements of some later mosques are derivative: for example, the dome of the nearby Madrasa Mader-e-Shah (Royal Theological College) of 1714.

There are an estimated 18 million bricks in the Royal Mosque and the exterior reveals of its openings are claimed to be faced with 472,500 tiles. Indeed, the building should be included among the world’s architectural feats because of the resplendent tile work on its main facade, its beautiful turquoise dome, and the interior. Tiles were a critical element of Persian architecture for two reasons: first, there was a practical need to weatherproof the clay bricks normally used in construction; and second, artistically, they were used to ornament the building. This was not merely for decoration but to define and articulate the underlying architectural form: tile work emphasized selected motifs and marked transitional points in the design, either by providing a patterned boundary or by the use of calligraphy. The Royal Mosque is widely celebrated for its exquisite haft rang (seven-color) tile work—colors were white, blue, yellow, turquoise, pink, aubergine, and green—which was developed extensively during the seventeenth century as the quality of glazes improved. It differed from conventional mosaic in that the full range of colors was used to create sinuous or calligraphic patterns on individual tiles, so that when they were placed, the overall design could be seen.

See also

Dome of the Rock; Sultan Ahmet Mosque (Qubbat As-Sakhrah)

Further reading

Ferrier, R. W., ed. 1989. The Arts of Persia. New Haven, CT: Yale University Press.

Colombek, Lisa, and Donald Wilber. 1988. The Timurid Architecture of Iran and Turan. Princeton, NJ: Princeton University Press.

Honarfar, Lutfullah. 1978. Historical monuments of Isfahan. Tehran: Ziba Press.

Maunsell sea forts

England

The coasts of Kent and Essex Counties, England, overlook the Thames Estuary, the only sea route to London. Throughout World War II it was constantly endangered by German minelayers, U-boats, and the Luftwaffe. From 1939 until 1942 the British navy patrolled the area; then a series of seven sea forts was built to permanently guard the river mouth. They were an innovative architectural and engineering achievement. The reinforced concrete and steel structures were entirely prefabricated in a Gravesend dry dock, floated to their locations, sunk, and anchored on the bottom of the sea, up to 9 miles (14 kilometers) off the coast. Although not as large as the now almost commonplace offshore oil and gas platforms around the world, the sea forts predated them by about five years, and the six so-called “Texas Towers” that form part of the U.S. lighthouse system by almost twenty.

Two kinds of forts, one for the navy and another for the army, were designed by the civil engineer Guy Maunsell. Even when war was little more than a threat, he submitted several proposals for seaward defenses, but it was not until October 1940—over a year after the outbreak of war—that the Admiralty commissioned him to design a prototype sea fortress. His initial costly proposal, for a 2,900-ton (2,640-tonne) pontoon supporting a gun battery, was shelved by the government. But when France fell, the Admiralty was moved to action and asked Maunsell to produce five sea forts for the Royal Navy.

The naval sea forts were essentially steel gun platforms with two 6-inch (150-millimeter) cannon and a Bofors antiaircraft gun. The huge structures were assembled by Holloway Brothers at the Red Lion Wharf, Gravesend, towed downriver by three tugs,