approach to the new technology, with very thick walls and a shallow dome, only visible from a certain distance or height. Bold contrasting colours of masonry, with red sandstone and white marble, introduce what was to become a common feature of Indo-Islamic architecture, substituting for the polychrome tiles used in Persia and Central Asia. The pointed arches come together slightly at their base, giving a mild horseshoe arch effect, and their internal edges are not cusped but lined with conventionalized "spearhead" projections, possibly representing lotus buds. Jali, stone openwork screens, are introduced here; they already had been long used in temples. Tughlaq architecture The tomb of Shah Rukn-e-Alam (built 1320 to 1324) in Multan, Pakistan is a large octagonal brick-built mausoleum with polychrome glazed decoration that remains much closer to the styles of Iran and Afghanistan. Timber is also used internally. This was the earliest major monument of the Tughlaq dynasty (1320–1413), built during the unsustainable expansion of its massive territory. It was built for a Sufi saint rather than a sultan, and most of the many Tughlaq tombs are much less exuberant. The tomb of the founder of the dynasty, Ghiyath al-Din Tughluq (d. 1325) is more austere, but impressive; like a Hindu temple, it is topped with a small amalaka and a round finial like a kalasha. Unlike the buildings mentioned previously, it completely lacks carved texts, and sits in a compound with high walls and battlements. Both these tombs have external walls sloping slightly inwards, by 25° in the Delhi tomb, like many fortifications including the ruined Tughlaqabad Fort opposite the tomb, intended as the new capital. The Tughlaqs had a corps of government architects and builders, and in this and other roles employed many Hindus. They left many buildings, and a standardized dynastic style. The third sultan, Firuz Shah (r. 1351-88) is said to have designed buildings himself, and was the longest ruler and greatest builder of the dynasty. His Firoz Shah Palace Complex (started 1354) at Hisar, Haryana is a ruin, but parts are in fair condition. Some buildings from his reign take forms that had been rare or unknown in Islamic buildings. He was buried in the large Hauz Khas Complex in Delhi, with many other buildings from his period and the later Sultanate, including several small domed pavilions supported only by columns. By this time Islamic architecture in India had adopted some features