Quite a number of studies, such as those by Íñiguez (1963, pp. 193-211), García Tapia (1990, pp. 172-181) and Lorda (1997), have discussed the cranes used in the construction of Spanish Renaissance buildings. All these papers deal with the surviving evidence about the construction of the Escorial complex, in particular the main church or basilica, such as a large number of contracts and other documents, a manuscript by Juan de Herrera called Architectura y machinas, and the outstanding drawing of the Escorial building site now at Hatfield House, England.
Another source for studies about Spanish Renaissance cranes is Lázaro de Velasco’s translation of Vitruvius’ De architectura libri decem. Velasco was the grandchild of a wood carver, Juan López de Velasco, and the son of Jacopo Torni, a Florentine painter and sculptor who was master mason of Murcia cathedral and architect of the church of San Jerónimo in Granada. Velasco followed an ecclesiastical career, holding a post as beneficiado in the chapter of Granada cathedral. However, his artistic interests show up in his work as illuminator of choir books, in his ill-fated attempt to obtain the office of master mason for Granada Cathedral in 1577 and in his complete translation of Vitruvius into Spanish, about 1564.
Of course, Velasco translates the passages of Vitruvius’ tenth book about machines, such as the tryspast and the polyspast, adding drawings of these hoisting devices. Furthermore, Velasco interpolates a long passage describing a big crane, similar but not identical to the ones in the Escorial, with a pyramidal frame, a windlass or mástil, moved by men treading inside a wheel, a rotating pole, ropes and a tryspast, but does not furnish a drawing of this big, non-Vitruvian crane.
After a brief review of Velasco’s career, I shall try to reconstruct the big crane in Lázaro de Velasco’s text, comparing it with the Escorial cranes, as depicted in the Hatfield drawing and described in the studies of Íñiguez, García Tapia and Lorda. I shall also discuss the possible sources of Lázaro de Velasco expertise on cranes; on the one hand, classical sources such as Vitruvius or Greek mechanics, on the other, the traditional and empirical lore of carpenters and masons, embodied in the ingenio or crane put up in Murcia cathedral in the years of Jacopo Torni, or the cranes that Velasco may have seen in Granada cathedral
