In a previous post about authors who constructed worlds that seemed to invalidate Nabokov's claim in LATH [ie: "[n]obody can imagine in physical terms the act of reversing the order of time. Time is not reversible."], Philip K. Dick's Counter-Clock World (1967) and Martin Amis's Time's Arrow (1991) were cited. Reversed time narratives were distinguished from "narratives that tell stories in reverse chronological order" by M-L Ryan (2009), who left out of her considerations Nabokov's permanent interest in reversions, hereafter and chronophobia as we find them being presented in "Ada", "Speak, Memory," and in several of his other writings as well.

By coincidence, Stan K-Bootle put me in touch with another kind of punch line*:
"There was a young lady called Bright
Who could travel much faster than light.
She set out one day
In a relative way
And returned on the previous night"

but not even naughty Laura in TOoL manages such a feat. Ada seems to get close to this idea when, after years of separation, she meets Van and her "solitary and precipitate advance consumed in reverse all the years of their separation as she changed from a dark-glittering stranger with the high hair-do in fashion to the pale-armed girl in black who had always belonged to him." However, this transformation is merely taking place in the narrator's mind and it follows a process that lies close to the Freudian transferential "re-edition of the past." (a central issue for psychoanalytic theories and practice).

In "ADA" there's a whimsical succession of wordplaying that verges on echolalia: "Allied to the professional and vocational dreams are ‘dim-doom’ visions: fatidic-sign nightmares, thalamic calamities, menacing riddles. Not infrequently the menace is well concealed, and the innocent incident will turn out to possess, if jotted down and looked up later, the kind of precognitive flavor that Dunne has explained by the action of ‘reverse memory’; but for the moment I am not going to enlarge upon the uncanny element particular to dreams — beyond observing that some law of logic should fix the number of coincidences, in a given domain, after which they cease to be coincidences, and form, instead, the living organism of a new truth."

Nevertheless, in a totally different mood, Van could recognize his mental automatisms and, not very successfully, try to "uncurl out of an indefinitely lengthy trance, and note with wonder that the ship was going the other way or that the order of his left-hand fingers was reversed, now beginning, clockwise, with his thumb as on his right hand, or that the marble Mercury that had been looking over his shoulder had been transformed into an attentive arborvitae. He would realize all at once that three, seven, thirteen years, in one cycle of separation, and then four, eight, sixteen, in yet another, had elapsed since he had last embraced, held, bewept Ada...Numbers and rows and series — the nightmare and malediction harrowing pure thought and pure time — seemed bent on mechanizing his mind."

Van often swerves, subreptitiously, to go against the hateful Signy Mondieu Mondieu and when he insists on the prevalence of a deliberate operation that can efficaciously put the past in reverse gear: "In the same sense of individual, perceptual time, I can put my Past in reverse gear, enjoy this moment of recollection as much as I did the horn of abundance whose stucco pineapple just missed my head, and postulate that next moment a cosmic or corporeal cataclysm might — not kill me, but plunge me into a permanent state of stupor, of a type sensationally new to science, thus depriving natural dissolution of any logical or chronal sense."

The same themes discussed in LATH seem to constitute ADA's alchemical corpus: "My aim was to compose a kind of novella in the form of a treatise on the Texture of Time, an investigation of its veily substance, with illustrative metaphors gradually increasing, very gradually building up a logical love story, going from past to present, blossoming as a concrete story, and just as gradually reversing analogies and disintegrating again into bland abstraction.." **

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*- Arthur Buller in Punch, 19 Dec. 1923.

** - Although Nabokov takes his time to rally against Einstein's Relativity Theory and time-space, most often he has in mind narratological time and fiction. Here is another example which departs fromVan's maniambulations and leads to his "standing of a metaphor on its head not for the sake of the trick’s difficulty, but in order to perceive an ascending waterfall or a sunrise in reverse: a triumph, in a sense, over the ardis of time." Unfortunately for me, I haven't yet really grasped its objective non-poetic meaning.