Transcript: The Architecture of Bubbles | May 05, 1990

(music plays)

Outside a diner, a man reads the paper, another man juggles and a magician plays tricks. The name “The science Café” appears in neon lights on one of the windows. Inside, the waitress shows a menu that reads “The Science Café proudly offers food for thought. Science demonstration from Ontario Science Centre. The architecture of bubbles. Presented by Peter Harris. Producer and director: Michael Kushner. Researcher: Wally Longul.”

A caption reads “Peter Harris. Ontario Science Centre.”

Peter is in his forties, with very short black hair and a beard. He wears glasses, blue trousers and a blue polo T-shirt.

He stands by a table with a flask, a plastic tray with soapy water and a giant bubble wand.

Peter says I'D LIKE TO TALK A LITTLE BIT
ABOUT THE SHAPE OF BUBBLES.
WHAT YOU'LL FIND IS THAT
BUBBLES ARE USEFUL TOOLS
FOR EXPLAINING WHAT HAPPENS
BOTH IN NATURE AND ALSO IN
SOME OF OUR ARCHITECTURE.
IF WE LOOK AT AN ORDINARY SOAP
FILM ON A RECTANGULAR FRAME,
IF I MAKE A BUBBLE,
WATCH THE RESULTING SHAPE.
WHAT WE GET IS A BUBBLE WHICH
IS APPROXIMATELY THE SHAPE
OF A SPHERE.
WE'VE GOT ONE BUBBLE
ACTING BY ITSELF.
SO WE'VE GOT SURFACE TENSION
CAUSING THIS BUBBLE TO FORM
WHEN IT'S CLOSE
TO BEING A SPHERE.
NOW, CONTRAST THAT
WITH THIS SITUATION.
IN THIS CASE, WHAT WE'VE GOT
IS A FRAME WHICH HAS THREADS
SUSPENDED IN THE CENTRE.
NOW, IF I MAKE A BUBBLE
WITH THIS FRAME, WATCH THE
DIFFERENCE FROM THE FIRST ONE.
WHAT WE GET ARE A NUMBER OF
BUBBLES ALL JOINED UP TOGETHER.
AND NO ONE BUBBLE IS A SPHERE.
IN THIS CASE, EACH BUBBLE
IS ACTING ON ITS NEIGHBOUR.
NOW, IF YOU TAKE THIS AS A
MODEL, WHAT WE CAN DO IS USE
IT TO HELP EXPLAIN
PATTERNS IN NATURE.
FOR EXAMPLE, AS I BLOW A
BUBBLE ONTO THE TABLE HERE,
WATCH WHAT HAPPENS.
ONE BUBBLE BY ITSELF
FORMS A HEMISPHERE SHAPE,
SORT OF A DOME.
BUT AS I ADD BUBBLES ONE
BY ONE, WATCH WHAT HAPPENS
IN THE VERY CENTRE.

He blows a number of adjacent bubbles.

He says WHAT YOU'LL FIND IS THAT WHEN
BUBBLES JOIN UP TOGETHER,
WE GET THIS CHARACTERISTIC
HEXAGON IN THE MIDDLE.
IF YOU'VE EVER LOOKED AT A
BEEHIVE, ONE OF THE THINGS
YOU'LL NOTICE IS THE HONEYCOMBS
ACHIEVE SIMILAR TYPE SHAPES.
ONE BEE WOULD MAKE A CIRCULAR
CELL, BUT WHEN YOU'VE GOT
THOUSANDS OF BEES ALL ACTING
TOGETHER, EACH CELL CROWDS
UPON ITS NEIGHBOUR.
HEXAGONS PILED UP ONE BY
ONE ON TOP OF EACH OTHER.
A VERY STABLE SHAPE, AND
VERY, VERY ECONOMICAL.
THE BUBBLES FORM
MINIMAL SURFACE AREAS.
THEY TRY TO BE AS
SMALL AS THEY CAN BE.
THE SAME THING WITH THE BEES.

A fast clip shows images of a beehive.

He says THEY'VE GOT A LIMITED AMOUNT
OF WAX TO USE, SO THIS SHAPE
HAS EVOLVED BOTH BECAUSE OF
PHYSICS BUT, IN THE LONG TERM,
IT ALSO SAVES THEM WAX.
[buzzing]
NOW, TO HELP EXPLAIN MINIMAL
SURFACE AREAS, IF WE HAVE A
LOOK AT OUR FRAME
WITH THE THREADS.
IF I POKE THE MIDDLE,
WATCH WHAT HAPPENS.

The threads take a circular shape.

He says WHAT YOU FIND HAPPENING IS
THAT THE THREADS HAVE BEEN
DRAWN TOWARDS THE OUTSIDE.
IN FACT, IF I TUG AT
THEM, AND THEN LET IT GO,
IT SNAPS BACK.
THE BUBBLE FILM IS
LIKE AN ELASTIC BAND.
IT'S STRETCHED, BUT IF IT
CAN, IT WILL SNAP BACK.
NOW, IF I TRY TO POKE THE
CORNERS, WATCH WHAT HAPPENS.
AS I POKE THEM ONE BY ONE,
WHAT YOU FIND HAPPENING IS NOW
THE THREADS ARE DRAWN
TOWARDS THE INSIDE.
AND, AGAIN, IF I TUG AT
IT... IT ALWAYS SNAPS BACK.
THIS IS VERY USEFUL FOR
STUDYING CERTAIN STRUCTURES
IN ARCHITECTURE.
IN FACT, AT THE MUNICH
OLYMPICS, THERE ARE A SERIES
OF BUILDINGS MODELLED
ON SOAP FILMS.
THIS IS PRECISELY WHAT
THE ARCHITECT DID.
HE WATCHED WHAT HAPPENED
AS SOAP FILMS INTERACTED.

Images of buildings in the shape of a tent made of spider webs appear.

He says YOU COULD USE LIGHTWEIGHT
FABRICS FOR THE SOAP, AND YOU
COULD USE SOMETHING LIKE
STEEL CABLES FOR THE THREAD.
SO WHAT WE'VE GOT HERE
IS A VERY USEFUL MODEL.
SO WHETHER IT'S NATURE OR
ARCHITECTURE, THE SAME LAWS
APPLY, AND WE CAN USE SOAP
FILM TO HELP EXPLAIN
WHAT'S HAPPENING AND WHY.

(music plays)

A slate appears with the caption “To make the bubble solution: 1- Two parts dish soap; 2- Six parts water; 3- Two parts glycerine.”

Another slate appears with the caption “For more information read: Encyclopaedia Britannica. Micropaedia, 15th edition. Look under honeybee.”

Another caption reads “A production of TV Ontario. The Ontario Educational Communications Authority. 1989.”

Watch: The Architecture of Bubbles