Bottles are introduced in Chapter One as the new way in which humans are created and grown. Right off the bat, this just seems very, very wrong. But far more disturbing than the notion of little zygotes inside bottles is the notion of full-grown humans being similarly trapped. Now we're in the realm of the metaphor. Of course, Huxley being Huxley, we're told directly that this is what he's going for in Brave New World. Look at Mustapha's words in Chapter Sixteen: "Even after decanting, [man is] still inside a bottle – an invisible bottle of infantile and embryonic fixations. Each one of us, of course, […] goes through life inside a bottle."
Let's go back to some earlier mentions of bottles.
Take a look at Lenina and Henry's date: "Bottled, they crossed the street; bottled, they took the lift up to Henry's room on the twenty-eighth floor. And yet, bottled as she was […], Lenina did not forget to take all the contraceptive precautions." OK, great, Lenina and Henry are trapped inside a bottle. But what is it that traps them? Let's look at some more text: "Lenina and Henry had what they wanted […] they might have been twin embryos gently rocking together on the waves of a bottled ocean of blood-surrogate." OK, so when the text talks about them being bottled, what it really means is that they're infantile. Makes sense, right? Pre-infants are grown inside bottles, so infantile imagery should go hand in hand with bottle imagery.
Now look at one more passage, this time the Orgy-porgy scene with Bernard: "And as they sang, the lights began slowly to fade – to fade and at the same time to grow warmer, richer, redder. […] In their blood-coloured and foetal darkness the dancers continued […] in the red twilight."
Wait a minute…red light…does that sound familiar? Indeed, yes. Hop back to Chapter One and listen to Henry Foster: "Embryos are like photograph film […]. They can only stand red light." Exclamation point! If the twelve people at the solidarity service are bathed in red light, it must have something to do with them being embryos, with them being bottled, and with them being infantile – just like Henry and Lenina on their date. So what do these two scenes have in common?
Sex. The adults who are bathed in red light and trapped inside metaphorical bottles are made infantile when they have sex. Why? Think about babies. When they want something, they cry. When they're hungry, they eat. They basically have no restraint. They're servants to their impulses. There's no length of time for them between a desire and the consummation of their desire. If this language also sounds familiar, it's because we took it from Mustapha Mond in Chapter Three: "Feeling lurks in that interval of time between desire and its consummation. Shorten that interval, break down all those old unnecessary barriers." Because the adults of the World State have been trained to give into their every desire, especially sexual impulses, they have also been trained to be infantile, to be bottled, to be just like those embryos bathed in the red light. And as proud as we would like to be for coming up with this all on our own, we have to give credit to Bernard, who very famously said to Lenina in Chapter Six: "[We're] infants where feeling and desire are concerned. […] That's why we went to bed together yesterday – like infants – instead of being adults and waiting."
The tragedy lies in the results of such infantile behavior. Mustapha claims that the indulgence of all impulses is freeing – the citizens of the World State are freed from the pain of waiting and wanting. In fact, however, it is this sort of indulgence that imprisons the citizens and bottles them up just like infants. They aren't free to act on impulses, they are instead slaves to their basest desires.