Please, some lyric help needed.

[elshiva]

I'm working on a review of Roxy Music's "Stranded" as sort of diversion during my illness (I have ulcers, gall stones, and maybe other gastrointestinal problems). Anyways, I am having some trouble with a certain phrase, "jet black magic." Now let me give you the context, here's the song:

Street Life
(Bryan Ferry)

Wish everybody would leave me alone -yeah
They're always calling on my telephone
When I pick it up there's no one there
So I walk outside just to take the air
Come on with me cruising down the street
Who knows what you'll see, who you might meet
This brave new world's not like yesterday -
It can take you higher than the milky way
Now I'm blinded I can't really see - yeah
No more bright lights confusing me - no
Don't ask me why I'm feeling blue
'Cause loving you is all I can do
Hey good-looking boys - gather around
The sidewalk papers gutter-press you down
All those lies can be so unkind,
They can make you feel like you're losing your mind
Street Life
Street Life
Street Life
What a Life
Back to nature boys - Vasser girls too
Watch what you say, or think, or do
Continental-style strasse girls might
But you know exactly if it's wrong or right
Education is an important key - yes
But the good life's never won by degrees - no
Pointless passing through Harvard or Yale
Only window shopping - it's strictly no sale
Week end starts Friday soon after eight
Your jet black magic helps you celebrate
You may be stranded if you stick around
- And that's really something...

© E.G. Music Ltd 1973
http://www.roxyrama.com/classic/lyrics/roxy_music/street_life.shtml

And here's a live performance of it, if that helps:
http://www.youtube.com/watch?v=s4qfMMbuIy0

If that link doesn't work try:
http://www.youtube.com/watch?v=prlt_3v5G84

My guesses are that "jet black magic" refers to beer, but I could be wrong. Something that helps him celebrate on weekends. I've checked urban dictionary and there's nothing on that phrase. Thank you for reading and your patience.