Nice links Jeff! Thanks!
The W8UZZ has quite the collection!

Irv VE6BP

Jeff Liebermann wrote:
On Wed, 31 Dec 2014 20:48:15 -0000, "gareth"
wrote:

In the textbooks, a capacity hat is shown as having a capacity down
to ground (in the case of a marconi antenna), but if you do the calculations
based on the physical dimensions, the resulting capacitance is so small
as to be meaningless.

So, .... what is the real picture here?

http://www.k0bg.com/caphats.html
http://en.wikipedia.org/wiki/T-Antenna
http://www.buzzbar.com/w8uzzch.html
http://www.smeter.net/antennas/short-top-hat-loaded.php
http://www.dxengineering.com/techarticles/hotrodzandmobileinstall/dx-engineering-hot-rodz-antenna-capacity-hats