25-4: me encontré con que, etc.: con governs the whole following clause as its object. Psychologically an intervening noun is indicated: I met with (the discovery) that I could not, etc.
25-5: haga són: (make sound) play. Alarcón has accented són to distinguish it from the verb son.
26-1: Pedro Pablo Rubens: Peter Paul Rubens, the great Flemish painter (1577-1640). He enjoyed much royal patronage, and consequently much of his work is now in the galleries of Spain and France.
26-2: Castilla la Nueva: the southern portion of the province of Castile, in central Spain, the northern portion being called Castilla la Vieja.
26-3: de feísima capilla: una is understood before feísima.