stability favouring dynamic expression. In 1556, French author Philibert Jambe de Fer gave a set of fingerings for hybrid instruments such as the Rafi and Grece instruments that give a range of two octaves. Here, the 15th was now produced, as on most later recorders, as a variant of the 14th instead of as the fourth harmonic of the tonic, as in Ganassi's tables. Documentary evidence: treatises The first two treatises of the sixteenth century show recorders that differ from the surviving instruments dating to the century: these are Sebastian Virdung's (b. 1465?) (1511), and Martin Agricola's (1486–1556) similar (1529), published in Basel and Saxony respectively. , the earliest printed treatise on western musical instruments, is an extract of an earlier, now lost, manuscript treatise by Virdung, a chaplain, singer, and itinerant musician. The printed version was written in a vernacular form of Early New High German, and was aimed at wealthy urban amateur musicians: the title translates, briefly, as "Music, translated into German ... Everything there is to know about [music] – made simple." When a topic become too complex for Virdung to discuss briefly, he refers the reader to his lost larger work, an unhelpful practice for modern readers. While the illustrations have been called "maddeningly inaccurate" and his perspectives quirky, Virdung's treatise gives us an important source on the structure and performing practice of the recorder in northern Europe in the late fifteenth and early sixteenth centuries. The recorders described by Virdung have cylindrical profiles with flat heads, narrow windows and long ramps, ring-like turnings on the feet, and a slight external flare at the bell (above, far left and middle left). Virdung depicts four recorders together: a or (basset) in F3 with an anchor shaped key and a perforated fontanelle, two tenors in C4 and a (alto) in G4. According to Virdung, the configurations F–C–C–G or F–C–G–G should be used for four-part music, depending on the range of the bass part. As previously mentioned, the accuracy of these woodcuts cannot be verified as no recorders fitting this description survive. Virdung also provides the first ever fingering chart for a recorder with a range of an octave and a seventh, though he says that the bass had a range of only an octave and sixth. In his fingering chart, he numbers which fingers to lift rather than those to put down and, unlike in later charts, numbers