"To a child who had never seen an escalator before this belt might have looked like a giant liquorice strap.
"Or maybe she thought its warm, moving form, as it curved down into the floor, was like a tongue disappearing into a throat. When the world is a giant adventure playground, why not?"
Looking at the successive frames of Oettli's negatives from the department store, it is clear there was nothing staged about the photo, says McCredie.
"He saw it quickly, took one shot and moved on," McCredie said.
"You can see that in the successive frames he shot in the store – some massed desktop fans, a man signing a hire-purchase agreement or similar, and then the girl.
"Did the girl know she had been snapped? If she did, would she have understood anything of Oettli's purpose? Would anyone?"
The photo is on display at Te Papa until October 13, and the museum is optimistically hoping the subject of this moment in history may come forward.
"Who is the girl? Is she out there somewhere?" McCredie said.
"Does she remember the sensation of tongue on belt? Did she decide that maybe she wouldn't do that again?
"As an adult, does she feel a twinge of suppressed excitement when she sees an escalator?"
The image is part of an exhibition on display at Te Papa called The New Photography – Life in the 60s and 70s.
If you think you may be the girl captured, or have any info on who she may be, you can contact Te Papa on (04) 381 7000.