Would this cap work?

To: tesla-at-poodle.pupman-dot-com
Subject: Would this cap work?
From: Tesla List <tesla-at-stic-dot-net>
Date: Fri, 30 May 1997 09:05:17 -0500
Approved: tesla-at-stic-dot-net

Subject:  Would this cap work?
  Date:   Thu, 29 May 1997 13:54:36 -0700 (PDT)
  From:  Brandon Doughan <fiveht-at-well-dot-com>
    To: tesla-at-pupman-dot-com

Perhaps Im not the first to think of such a cap, but I have an idea
along 
the lines of the beer bottle set-up.

Would it not be possible to take a length of polyethylene (or other 
appropriate material) tubing, carefully seal off one end, fill with
brine, 
seal the other end around one terminal (with a bit of, say Cu wire, 
extending into the brine), and then immerse this length into a brine
bath 
containing the opposite terminal?  This tubing could be arranged in a 
spiral or zig-zag such that you effectively have your two plates.

The total capacitance could easily be figured knowing your dielectric, 
thickness of tubing and the area of cylinder submerged (whatever that 
formula is...).

As I see it, the advantage to this setup is in its ease of
construction.  
To obtain a certain capacitance, simply cut that length of tubing.  You 
could even tune by varying the amount of tubing that is submerged.  On 
the down side, it seems possible that pressure buildup could split open 
the tubing.

What do you think?

Take Care- Brandon