tube coils

To: tesla-at-pupman-dot-com
Subject: tube coils
From: RODERICK MAXWELL <major-at-vicksburg-dot-com>
Date: Thu, 05 Sep 1996 18:26:27 -0500

I have not even finished my first capacitor discharge tesla coil and already I,m 
looking forward to building a tube driven coil! I've odered a couple of books from 
I.T.S. __Vacuum Tubes In Wireless Communication__ by Elmer E. Bucher ,and __Vacuum Tube 
Tesla Coils__by J.F. Corum and K.L. Corum. I have built several high voltage projects 
using induction coils and a solid state Mosfet driver, but I have never built 
__anything__ that uses tubes. 
  In __Vacuum Tubes In Wireless Comunication__ it describes the vacuum tube as a 
rectifier. It also shows the direction of electron flow from the filament to the plate.
This part I comprehend and understand well. What I have a hard time visualizing is 
current flow from the plate to the filament! If the flow fom the filament to the plate 
is composed of electrons, what is current flow from the plate to the filament composed 
of and what is the mechanism that allows this to happen? Is it simular to hole flow in 
semiconductor material???? Could someone that has experience with tube electronics 
please answer these questions for me so I can sleep nights?