I posted the following information on HISTARCH in January of 2002
which is a discussion on the role of tank furnaces in causing the switch to
selenium as a decolorizer.  The tank furnace had more to do with the switch
to selenium than supplies during WWI.  Bill Lockhart has a much longer
discussion of this that will be published in Historical Archaeology in the
near future.

Solarized glass and the change to selenium as a decolorizer.

      The switch to selenium as a decolorizer began before WWI.  Because
the Owens Automatic Bottle-Blowing Machine worked from a tank furnace, it
helped bring about the switch to selenium.  Manganese dioxide was not very
stable in a tank furnace because it is difficult to maintain an oxidizing
atmosphere in such a furnace.  Selenium was much more stable in that
environment.  One of the earliest publication of information on the used of
selenium as a decolorizer came out in 1911 (Angus-Butterworth 1948:68-69).
Keep in mind that the half of the bottles produced in the United States in
1917 was being made on the Owens Machine.  I have not seen very many
solarized Owens-made bottles.

Angus-Butterworth
      1948  The Manufacture of Glass.   Pitman Publishing Corp. New York

For a discussion of this transition, see "Impact of Mechanization in the
Glass Container Industry: The Dominion Glass Company of Montreal, a Case
Study."  Historical Archaeology 1983 volume 19, no. 1:38-50.

      Tony McNichol and I gave a paper at the SHA on dates for
suction-scarred bottoms and we have been gathering information on the
subject.  Opinions we do not need, however comments with citations would be
most appreciated.

George L. Miller
URS Corporation
561 Cedar Lane
Florence, New Jersey 08518