** - It refers to the moment when the police arrested HH after Q's murder. They bring up an event that took place approximately two years before that - and close to when Lolita left him at the hospital and he decided to shoot "his brother.". Although he hadn't killed anyone at that time, he admits that he submitted to the cops because he was afraid that he'd be accused of child-molestation (and then he mentions "a life of crime") and, therefore, his murderous project concerning his "fiend" could not be carried out. The timing in very neat.

 

"I was soon to be taken out of the car [   ] like a patient [   ] And while I was waiting for them to run up to me on the high slope, I evoked a last mirage of wonder and hopelessness. One day, soon after her disappearance, an attack of abominable nausea forced me to pull up on the ghost of an old mountain road that now accompanied, now traversed a brand new highway[   ] As I approached the friendly abyss, I grew aware of a melodious unity of sounds rising like vapor from a small mining town that lay at my feet, in a fold of the valley [   ] But even brighter than those quietly rejoicing colors [   ] both brighter and dreamier to the ear than they were to the eye, was that vapory vibration of accumulated sounds that never ceased for a moment, as it rose to the lip of granite where I stood wiping my foul mouth. And soon I realized that all these sounds were of one nature[  ] Reader! What I heard was but the melody of children at play [   ] I stood listening to that musical vibration from my lofty slope [   ] and then I knew that the hopelessly poignant thing was not Lolita's absence from my side, but the absence of her voice from that concord.[   ] When I started, fifty-six days ago, to write Lolita, first in the psychopathic ward for observation, and then in this well-heated, albeit tombal, seclusion, I thought I would use these notes in toto at my trial, to save not my head, of course, but my soul. In mind-composition, however, I realized that I could not parade living Lolita. I still may use parts of this memoir in hermetic sessions, but publication is to be deferred.[   ] "