 The earliest extant record of a solar equatorium, that is, one to find the position of the sun, is found in Proclus's fifth-century work "Hypostasis", where he gives instructions on how to construct one in wood or bronze.Although planetary equatoria were also probably made by the ancient Greeks, the first surviving description of one is from the "Libros del saber de astronomia" ("Books of the knowledge of astronomy"), a Castilian compilation of astronomical works collected under the patronage of Alfonso X of Castile in the thirteenth century, which includes translations of two eleventh century Arabic texts on equatoria by Ibn al‐Samḥ and al-Zarqālī.