In 1534, the Sicilian mathematician Francesco Maurolico (1494-1575) compiled a brief work titled Ex Heronis et aliorum spiritalibus, in which he described and illustrated 11 pneumatic and hydraulic devices. Of these, seven were taken directly from Hero's Pneumatica through Giorgio Valla's partial Latin translation of 1501. Of the remaining four, three were simple devices accompanied by similar realistic drawings, suggesting a common but as yet unidentified source. One of these perhaps derived ultimately from Philo's Pneumatica, while another was probably adapted from a more complex device described by Vitruvius in De architectura and attributed to Ctesibius. Finally, one device was probably invented by Maurolico himself, suggesting that he took a practical interest in such pneumatic-hydraulic devices.