Evidence for the crank combined with a connecting rod appears in the Hierapolis mill, dating to the 3rd century; they are also found in stone sawmills in Roman Syria and Ephesus dating to the 6th century. The pediment of the Hierapolis mill shows a waterwheel fed by a mill race powering via a gear train two frame saws which cut blocks by the way of some kind of connecting rods and cranks. The crank and connecting rod mechanisms of the other two archaeologically-attested sawmills worked without a gear train. Water-powered marble saws in Germany were mentioned by the late 4th century poet Ausonius; about the same time, these mill types seem also to be indicated by Gregory of Nyssa from Anatolia.