Insulated double glass window assembly

An apparatus for selectively varying the color of a window, said apparatus comprising:

• a double pane window assembly comprising two at least generally parallel, spaced transparent or translucent panes defining a volume therebetween,
• at least three liquid reservoirs containing respectively two different colored antifreeze liquids and a cleaning liquid capable of removing residue antifreeze liquid from said window volume,
• conduit means for connecting said liquid reservoirs to said double pane window assembly and opening to said volume,
• a pump operatively positioned within said conduit means intermediate of said liquid reservoirs and said double pane window assembly,
• solenoid valve means within said conduit means between each liquid reservoir and said pump for selectively connecting said pump to a given liquid reservoir,
• a reversible electric motor for driving said pump,
• switch means for controlling reversible energization of said pump motor, and
• selector means for preventing energization of more than one of said solenoid means such that between pumping of different colored antifreeze liquids to and from said window volume assembly, said cleaning liquid may be pumped from its liquid reservoir to said window assembly to flush residue antifreeze liquid from said volume.