This refers to the effect of west wind in the water. The question that comes up when reading the third canto at first is what the subject of the verb "saw" (33) could be. On the one hand there is the "blue Mediterranean" (30). With the "Mediterranean" as subject of the canto, the "syntactical movement" is continued and there is no break in the fluency of the poem; it is said that "he lay, / Lull'd by the coil of his crystalline streams, / Beside a pumice isle in Baiae's bay, / And saw in sleep old palaces and towers" (30–33). On the other hand, it is also possible that the lines of this canto refer to the "wind" again. Then the verb that belongs to the "wind" as subject is not "lay", but the previous line of this canto, that says Thou who didst waken ... And saw" (29, 33). But whoever—the "Mediterranean" or the "wind"—"saw" (33) the question remains whether the city one of them saw, is real and therefore a reflection on the water of a city that really exists on the coast; or the city is just an illusion. Pirie is not sure of that either. He says that it might be "a creative you interpretation of the billowing seaweed; or of the glimmering sky reflected on the heaving surface". Both possibilities seem to be logical. To explain the appearance of an underwater world, it might be easier to explain it by something that is realistic; and that might be that the wind is able to produce illusions on the water. With its pressure, the wind "would waken the appearance of a city". From what is known of the "wind" from the last two cantos, it became clear that the wind is something that plays the role of a Creator. Whether the wind creates real things or illusions does not seem to be that important.