I had stolen the honey of a spasm
1) Accomplished or enjoyed by stealth, secret
1) a sweet viscid fluid, of various shades from nearly white to deep golden, being the nectar of flowers collected and worked up for food by certain insects, esp. the honey-bee
2) applied to products of nature of, or resembling honey: esp. a. the nectar of flowers; b. a preparation consisting of the expressed juice of dates or other fruit of palm trees
1) Sudden and violent muscular contraction of a convulsive or painful character
To put it bluntly, Humbert was able to orgasm without Lolita being aware
The conjurer had poured milk, molasses, foaming champagne into a young lady's new white purse; and lo, the purse was intact
1) one who performs tricks with words
2) one who practises conjuration; one who conjures spirits and pretends to perform miracles by their aid; a magician, wizard
1) a person's conscience, heart, etc., regarded as a place of safe storage or supply; a person's thoughts or store of ideas
2) more generally: a natural receptacle in an animal (or plant) resembling a bag or pocket, as a pouch, a marsupim, a cyst, an ovicapsule, etc.
1) Untouched; not affected by anything that injures, diminished, or sullies; kept or left entire; unblemished; unimpaired
Humbert had acted in a way that got into Lola's head. His action was more in his words (constantly calling her "Darling," and the pet name "Lolita"). From these words, Lolita was able to hold HH's feelings and manipulate them to fit her wants. This sentence is very biological and her "purse" was untouched with the "milky foaming molasses," but even though he did not have intercourse with her at this point, the process of having (and the natural processes of) an orgasm are alluded to in this sentence.
Thus had I delicately constructed my ignoble, ardent, sinful dream
1) not noble in disposition, nature, or quality; mean, base, sordid; dishonourable. Of persons, their actions, aims, desires, etc.
1) Burning, on fire, red-hot; fiery, hot, parching
2) Inflammable, combustible
3) Glowing with passion, animated by keen desire; intensely eager, zealous, fervent, fervid
Humbert created a dishonest and passionate and corrupted image/idea of Lolita.
The basic understanding of this paragraph is in no way one of the more complex paragraphs of the novel, however it is the words used to describe the event that add a beauty to the ugliness of this scene. The reader comprehends that Humbert has pleasured himself in the presence of a 12yr old girl and is (much like Lolita) "encased" in this dream of HH's. Words flow and bring images of youth and sweetness to mind [honey, milk, molasses, champagne, new, white, dream, fanciful, floating]. But these words only serve to distract the active-reader and repulse the passive-reader. This is one instance that proves how wonderful a narrator HH is. He is able to absolve his sins by writing with such rich language. Other than the duality of the words [innocent words that can have their meanings contorted into grotesque associations], HH addresses three persons in this paragraph.
Person 1: The jury (the reader)
He repeats himself to the reader to hone in on the idea of his innocence. "...without impairing the morals of a minor. Absolutely no harm done."
Person 2: Lolita
He addresses Lolita in a subtly obvious way. When he talks about pouring his conjuring ways into the purse, he lets Lolita (that may be reading this manuscript) know that indeed her conscience remained untouched. "...young lady's new white purse; and lo, the purse was intact."
Person 3: Himself
Then the end of the paragraph feels like a journal entry should. Self-reflexive. He reflexes that his "dream" of Lolita was an image he created and trapped Dolores in.