It is worth noting that in this he included the study of music theory and singled out for use the treatises of Aristoxenus, Euclid, Ptolemy, Boethius, Iordano and Zarlino.(44) In 1602 there appeared a Spanish edition, dedicated to the Duke of Lerma, of Jacques (`Diego') Besson's Theatrum instrumentorum et machinarum (Lyon, 1578), which describes a kind of
reductional compasses.(45) Four years later Andres Garcia de Cespedes, the professor of the court mathematical academy, published in Madrid his Libro de instrumentos nuevos de geometria, dedicated to Archduke Albert, in which he claims to have written other treatises in Spanish on the various metal mathematical instruments which he had made and calibrated himself (f.2r).