My photograph of the window (and view to Mt Coot-tha on an overcast day) was taken from Royal Queensland Art Society building on Petrie Terrace, Brisbane.

I don’t know the age of this window but the visual wobble was initially disconcerting until my eyes worked out what was going on! GBW

It wasn’t until afterwards that I saw the bubbles in the glass pane following my visit to the RQAS portrait exhibition.  In this case, the bubbles clustered together are called ‘seed bubbles’ and enhance the old-fashioned charm of the window.

Bubbles in old glass bottles and windows are actually air pockets that became trapped during the manufacturing process. True air bubbles are rare in glass produced after 1920, so the presence of a bubble may help to date a bottle or window.

Crude glass almost always contains bubbles, which often adds to its appeal and value among collectors.  Apparently collectors do not view bubbles as ‘flawed’ or ‘damage’ and some even prefer bubbles because they add to the visual appeal of the glass.

♥ Gretchen Bernet-Ward