Everyone Is You and Me
See yourself become someone else.
You and a partner sit on opposite sides of a "two-way" mirror. You vary the amount of
light illuminating your face while your partner varies the amount of light illuminating his
or her face. As you adjust the light, you will see yourself gradually assume aspects of
your partner's features, so that your image becomes a "composite" person.
A piece of ordinary window glass,
approximately 1 x 1 foot (30 x 30 cm).
Aluminized Mylar™ reflecting film to cover one side of the glass. (You can buy this
at most hardware or do-it-yourself stores.)
2 goose-neck desk lamps.
2 dimmer switches. (Ready-to-use types are available at hardware stores. No wiring
is necessary. The configuration used in the photo requires two adapters. See the diagram.)
2 extension cords.
Mirror stand of some sort. (There are any number of ways to stand the glass up; see
the Assembly section.)
A partner. Adult help.
(1 hour or less)
You can make a two-way mirror from
inexpensive Mylar™ reflecting film
and ordinary window glass. The
variable illumination is accomplished
with dimmers commonly available at
hardware stores.
To make a two-way mirror, put the
reflecting film on one side of the
glass, following the
instructions for the particular brand of
film used. Cover the
edges of the glass with cloth tape to
prevent the film from peeling and to avoid cuts from any sharp edges on the glass.
Place the lamps as shown in the diagram. Connect each lamp to a dimmer switch and an
extension cord.
Stand the mirror on a table. This may be done by standing the mirror between two heavy
masses (such as 2 pound [1 kg] lab masses), or by making a wooden stand of some sort.
A "sandwich" of two pieces of wood with the mirror in the middle, all rubber-banded
together, will work. If you have a table saw, cut a slot for the mirror in a piece of wood.
Anything that works will do.
(15 minutes or more)
Sit across the table from your partner with the two-way mirror in between. The room
should be dimly lit or dark. Be sure that you and your partner are the same distance from
the mirror. You should be able to see both your partner's face through the mirror and your
own face reflected in the mirror. Line up your reflected eyes and nose so that they
coincide with your partner's. You will have to adjust your distance from the mirror as you
do this. Point one lamp directly at your face and have your partner point the other lamp
directly at his or her face. Adjust both lamps so they are initially very dim. Now use the
dimmer to vary the amount of light reaching your face. Have your partner adjust his or
her dimmer. Watch your features blend with your partner's features.
The mirror reflects about half of the light that hits it and transmits the other half. If your
lamp is dim, there's not much light to bounce off your face and reach the two-way mirror,
and your reflection will be dim. If your lamp is dim at the same time your partner's is
brightly illuminated, then light from him or her will be transmitted through the two-way
mirror and you will see his or her features clearly. As you make your lamp brighter and
your partner makes his or her lamp dimmer, you will see more of your own features and
less of your partner's. Your brain combines the two images into one perceived face.