Bubbler Oil

[Tom Droege <tdroege@veriomail.com>]

I did the test of putting the oil I am using in the freezer overnight and 
it was still viscous, stiffer but will probably work OK since it's purpose 
is to seal the system.

I am using "Light Mineral Oil U.S.P" from the drug store.  I buy USP 
chemicals at the drug store as they are guaranteed to be pure.  Thus a 
source of Isopropyl alcohol (cheap) that you can use to clean lenses.  It 
does not leave a residue as does other alcohols you buy in the hardware store.

Tom Droeegf