Refers to the semen... semen; until the 17TH century, used to be called, euphemistically, to intangible liquid four fundamental humors support, without which there could be no life. Galen did not consider it, which led to the subsequent lack of definition. º 1005.7 BW, CL, CT, SB, RM does not manage to define it as semen; but just see beings [1989:180-181] b. It same occurs with the medicine of those times: Arnau of Vilanova wrote a treaty called of wet radicali, published in Lyon, by B. William Huyon, according to Hernández Morejón [1842-1852: I, 221]; CF. also López de Villalobos, summary, pp. 234-235, or Mexia, Silva, II, p. 359: «and because this natural heat is nature's fire, and always wears and has needed that support, it was necessary thing and put God in your company the humidity ( that radical húmido doctors call and I call natural humidity ) in which maintained and sustained as the fire in the oil of the lamp». CF. the description of Luis Lobera de Ávila in Hernández Morejón [1842 - 1852:II, 318-320]; Reverte Coma [1992:44]. http://cvc.cervantes.es/literatura/clasicos/quijote/edicion/parte2/cap47/default.htm