One more word on this. Nabokov's "ex ponto" is a clear allusion to Virgil's Epistulae ex Ponto (Letters from the Black Sea). Since Shade had presumably never been on the Black Sea (Latin: ponto) but VN (and CK or VB) presumably had, might VN not be saying that through the Index runs the theme of exile? I.e., a "gentle wind" that both VN and CK share? But not JS.
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