It is in effect about LSD but Lennon gt the idea from a picture his son drew for him and he took the words from images in Alice in Wonderland.
For analysis of techniques used in the song here is a bunch of stuff I found (just copied and pasted hope it is of some help):
Style and Form
"Lucy ..." is comparable in many respects to "
Tomorrow Never Knows" and "
Strawberry Fields Forever". It is less subtle than either of those two songs, but it also all the more outrageous and not the least bit less ingenious.
It's also the most explicitly
drugs-oriented of the three; even the earlier precedents such as "
I'm Only Sleeping" and "
Dr. Robert" sound tame in comparison. Don't ever forget that just because the title of the song matches the name of picture painted by toddler Julian doesn't mean that the song
isn't's about the so-called "dreaded" Lysergic Acid
Plasticene porters with looking glass ties, indeed.
The music is certainly as mercurial and elusive as the imagery of the words, especially in terms of the constantly shifting key structure and the rhythmic alternation of 3/4 and 4/4 meters. There's also that typically Beatlesque manipulation of form in the way the bridge section is dropped for the final Verse sequence.
The use of drone-like harmony in the verse and rote repetition of a single phrase in the refrain lends an appropriate eyes-pinned hypnotic feeling to the piece.
Melody and Harmony
The melodic material is kept exceedingly simple in consideration of the combined metrical and harmonic challenges which underlie it. Hum it to yourself and listen to what it sounds like independently of the accompaniment. I mean, there's not much there if you take it out of context.
The song's three sections each have a distinct harmonic and melodic profile:
The verse is in the key of A and consists of a repeated chromatic filling out of the I chord. The tune just noodles around the five notes that outline the A-Major triad.
The bridge starts off in the key of B-flat but finishes up in the key of G. This seemingly remote modulation belies a loose relation between the two keys: G is the parallel Major of g minor, and the latter is the relative minor of B-flat. The tune here is almost monotonously stuck on the note D.
In order to provide some well-needed ballast-like oases of predictability, the Refrain is in G and stays close to home with the old I -» IV -» V progression. However, it also pivots on the D chord to get back to the key of A for the verses which follow it. The melody this time consists of a plain downward scale.
Arrangement
Lewisohn says the opening ostinato lick is played on a special Hammond organ stop that sounds like a celeste. Fine; the end result still sounds to my ears sounds like a harpsichord played back with as much seasick flutter as you'd get from my 35 year-old (and counting) Wollensak reel-to-reel tape deck.
Paul's standout performance on bass is ample proof of how the magical collaborative abilities of Messrs. Lennon and McCartney was extended well beyond the arbitrary task divisions of words-versus-music, or verses-versus- middle eights. I am especially impressed by the amount of variation provided by the bass part:
First verse: downbeats only ;
First bridge: every beat, largely with repeated notes;
First refrain: running eighth notes in Baroque fashion;
Second verse: downbeats only, again;
Second bridge: every beat, with more in the way of arpeggio outlines;
Second refrain: running eighth notes, again;
Third verse: more active and in a less regimented manner than previously;
Outro: more running eighth notes, this time with arpeggios as well as melodic runs.
The vocal parts show similar attention to structured variation:
Verses: John solo; at first with so little ADT that you can isolate a pristine single-track vocal by blocking out either of the stereo channels. Final phrase is more truly double-tracked.
Bridges: John solo; heavily echoed with mild ADT, and sounding like he's exhaling helium
First refrain: First phrase sounds like Paul solo but with ADT. Second phrase has John and Paul singing in unison. Third phrase has them singing in parallel thirds; with Paul as usual "on top", so to speak.
Second refrain: The parallel thirds start right in the first phrase.
Outro: First phrase has John and Paul in unison, but the rest of the entire outro is in parallel thirds.
Other instrumental details of note include the way the lead guitar always doubles the lead vocal in the bridges, the prominence of the organ during the outro, and the repeated, ultra close-up, yet sparing use of the tamboura drone; "is that you buzzin?" 2
