The brief Almoravid dynasty left no monuments behind it. Fez had already been founded by the Idrissites, and its first mosques (Kairouiyin and Les Andalous) existed. Of the Almoravid Fez and Marrakech the chroniclers relate great things; but the wild Hilalian invasion and the subsequent descent of the Almohads from the High Atlas swept away whatever the first dynasties had created. The Almohads were mighty builders, and their great monuments are all of stone. The earliest known example of their architecture which has survived is the ruined mosque of Tinmel, in the High Atlas, discovered and photographed by M. Doutté. This mosque was built by the inspired mystic, Ibn-Toumert, who founded the line. Following him came the great palace-making Sultans whose walled cities of splendid mosques and towers have Romanesque qualities of ma** and proportion, and, as M. Raymond Koechlin has pointed out, inevitably recall the "robust simplicity of the master builders who at the very same moment were beginning in France the construction of the first Gothic cathedrals and the noblest feudal castles." [Illustration: From a photograph from the Service des Beaux-Arts au Maroc Fez—Medersa Bouanyana] In the thirteenth century, with the coming of the Merinids, Moroccan architecture grew more delicate, more luxurious, and perhaps also more peculiarly itself. That interaction of Spanish and Arab art which produced the style known as Moorish reached, on the African side of the Straits, its greatest completeness in Morocco. It was under the Merinids that Moorish art grew into full beauty in Spain, and under the Merinids that Fez rebuilt the mosque Kairouiyin and that of the Andalusians, and created six of its nine Medersas, the most perfect surviving buildings of that unique moment of sober elegance and dignity. The Cherifian dynasties brought with them a decline in taste. A crude desire for immediate effect, and the tendency toward a more barbaric luxury, resulted in the piling up of frail palaces as impermanent as tents. Yet a last flower grew from the deformed and dying trunk of the old Empire. The Saadian Sultan who invaded the Soudan and came back laden with gold and treasure from the great black city of Timbuctoo covered Marrakech with hasty monuments of which hardly a trace survives. But there, in a nettle-grown corner of a ruinous quarter, lay hidden till yesterday the Chapel of the Tombs: the last emanation of pure beauty of a mysterious, incomplete, forever retrogressive and yet forever forward-straining people. The Merinid tombs of Fez have fallen; but those of their destroyers linger on in precarious grace, like a flower on the edge of a precipice.