 Both Einhard and Notker the Stammerer refer to the envoys travelling between Harun's and Charlemagne's courts, amicable discussions concerning Christian access to the Holy Land and the exchange of gifts.Notker mentions Charlemagne sent Harun Spanish horses, colorful Frisian cloaks and impressive hunting dogs.In 802 Harun sent Charlemagne a present consisting of silks, brass candelabra, perfume, balsam, ivory chessmen, a colossal tent with many-colored curtains, an elephant named Abul-Abbas, and a water clock that marked the hours by dropping bronze balls into a bowl, as mechanical knights—one for each hour—emerged from little doors which shut behind them.