Pat wrote, on Tue, 23 Dec 2014 11:01:12 -0500:

I don't think you fully understood his battery analogy. It really
generates voltage. Google thermocouple.

Here's a good explanation of how the flame rod works.
https://www.youtube.com/watch?v=be_it7G01gI

Now that I know how it works, I should be able to devise
a test that doesn't require me to measure 5 ua of current.