In various previous threads, we have wondered about Michter's calling its product "pot still whiskey" when, except for the small still installed in 1976, they clearly were using a column still. Many had speculated that they were claiming their whiskey was "pot still whiskey" because they were using a pot still doubler--exactly like everybody else.
Now it can be revealed. That is, in fact, the answer, as explained here in a Michter's tourist brochure. This brochure and a lot of other cool stuff can be found at this web site run by a descendant of the distillery's founder, Abe Bomberger.