Leonardo, Vol. 2, pp. 251-256.
Pergamon Press 1969. Printed in Great Britain

LIGHT SHOWS:

A KINETIC ART TECHNIQUE
USING CHEMICALS

D. R. Wier

Abstract

The author
describes the production of a light show by projecting light through
colored liquid materials on to a screen in the form of the wall of a
room. This type of chemical light show is also called a wet show.
He points out that a similar type of show was produced long ago by
alchemists with simpler materials.

The best
environment for light shows, the kinds of psychological reactions
reported by spectators, the basic equipment and supplies required,
and the source of visual effects are described in some detail.

Most of the
article is devoted to a useful catalog of various chemical materials
to place in a clear, concave watch glass (the author used one of
15-in. diameter, which was places on the top of a commercial-type
overhead projector) to produce interesting moving colored images.
These materials include: the starting solution placed in the watch
glass; acids and bases; pH indicators and dyes for producing various
colors,- and solvents for producing special effects. Ways of
producing additional effects by mechanical means are also mentioned.

1. INTRODUCTION

A type of kinetic art has been
mentioned by Malina which 'comprises the use of cinema equipment to
create pictures of changing composition and color projected on to a
framed area (the screen) [1]. The term light show, according to
Beck, is commonly used to describe projected kinetic art [2]. A wet
show is a type of light show produced with an overhead type projector
using liquid coloring materials. In this article, 1 will use the
terms light show and wet show synonymously.

Light shows, in one form or another,
have been produced since at least as early as 1732. Jung described a
type of light show practiced by medieval alchemists [3]. The
description quoted by Jung reads as follows:

Abtala Jurain son of Jacob Jurain and
Coahyl; translated from the Ethiopian into Latin and from Latin into
German by Johann Elias Miller, as follows::

Take of common Rainwater a goodly amount,
at least ten Stuebchens keep it well

shut in Glass Jar at least ten days,
then will the foulness and faeces settle on the bottom. Pour off the
clear Water and put it into a wooden Vessel that is shaped round like
a Ball; slice it through the middle and fill the Vessel one third
part full thereof. Then place it in the Sun at noon in a hidden or
separate Place.

This done, take a Drop of red Holy Wine
and let it fall into the Water, when you will forthwith behold a Fog
and a deep Darkness down on the Water, as indeed it was so at the
first Creation. If you then put in a second Drop, you will see the
Light coming out of the Darkness; whereupon put in again and again,
each quarter hour, a Third, then a Fourth, then a Fifth, then a Sixth
Drop, and then no more:: when if you let your eyes light on the
Water, one thing after another you will see, how God created every
Thing in 6 Days, and how this took place, and, suchlike Secrets that
cannot be spoken of, even I myself have not the Power to reveal them.
Before you undertake this Operation, fall down upon one Knee . . . ,
[Translated from Old German]

The light shows that 1 produced in my
apartment during 1965-1966 used a process similar to the one
described above, except that other chemicals were used than wine, the
light source was from an overhead projector rather than from the Sun
and the screen was the wall of a room. The subjective effects on
viewers were substantially the same as described by Jung.

Fig. 1. Image produced during a
chemical light show.

Fig.2. Image produced during a chemical
light show.

The kinds and combinations of chemicals
used were derived empirically after several months of
experimentation. Combinations initially used were later discarded
when better ones were discovered. Initially, the only chemical
reaction 1 used was the neutralization of vinegar with bicarbonate of
soda. The visual disadvantage of this reaction was that the reaction
product was insoluble in water and thus appeared black on the screen.

1 then tried neutralizing 50 per cent
solutions of sulfuric acid and of sodium hydroxide in the presence of
pH indicator dyes. Subsequent additions of other chemicals and the
testing of a variety of combinations resulted in the set of chemicals
and techniques described below. The images they produce may be seen
in Figs. 1 to 5.

11. CHEMICAL LIGHT SHOWS

1. The physical environment for a light
show

As many of the chemical reactions take
place

rather slowly, the physical environment
of the light show room ought to be restful. We used our bedroom,
with no furniture except for two lighted candles, with a white wall
as the screen. The entire floor space was covered with several
thicknesses of blankets, so that those who came to watch could
comfortably recline. A show lasted for about 30 minutes. Since many
persons came, the floor was often covered with spectators who found
themselves close together-a condition which contributed to an
intimate atmosphere.

Fig 5. Image produced during a chemical
light show.

2. Psychological effects

Psychological effects resulting from a
light show

include those resulting from viewing
the cinema. Some spectators found that the images reminded them of
moving Rorschach patterns. A spectator at one stage complained of
seeing blood' and this idea became so strong that she had to leave.
On the other hand, other spectators have come to the show irritable
and tense and have left calm and relaxed.

A show produced in a noisy bar caused
no noticable psychological effects in the patrons. Thus, 1 conclude
that a relaxed and quiet atmosphere is necessary if the maximum
psychological effect is to be obtained.

3. Basic equpment and supplies

The projector 1 used was an old
American Optical Company overhead projector. The frame was

metal and, over the year that it was
used, acquired a patina and crustation consisting of dyes, stains and
metallic sediments. 1 later purchased an Arnerican Optical Company
type Apollo 6 overhead projector which, due to its plastic
construction, was suscep tible to attack by the solvents and dyes.

A 15-in. diameter clear, concave watch
glass was used to hold the starting solution and additives. It was
usually cleaned with methyl ethyl ketone before it was placed on the
projection surface of the overhead projector. The watch glass was
then filled with a starting solution to a depth of about 1 in.

The infusion of additives and the
creation of vortices was accomplished with an infusor made of a
section of rubber hose, one end of which was fastened to a glass pipe
that had a tapered end much like a pipette. The other end of the
rubber tubing was attached to a rubber syringe. The pipette and
rubber tube were filled either with a reactive or a dye additive,
which was then introduced into the starting solution in the watch
glass. The projected images are more effective when the additive is
infused slowly so as not to agitate the surface of the solution too
much; although, occasional rapid infusion causes aesthetically
satisfying effects. The infusor may also be used to blow a fine
stream of air across the surface of the solution in order to cause
selective mixing of the liquids.

1 sometimes throw in solid materials,
such as indicator crystals, held between two fingers; after some
practice, 1 was able to throw a single crystal into a small bubble at
a distance of approximately 2 feet.

4. Source of visual effects

The chemical light show derives many of
its effects

from the fact that the liquids in the
watch glass are not homogeneously distributed in the starting
solution. Concentrations of various liquids or of solids can be
infused or thrown into different parts of the starting solution. An
operator should also learn the nature of the chemical reactions that
can occur between the starting solution and reactive additives, in
order to choose the type of effects he wishes to produce. Motion of
the liquids occurs either through Agitation caused by infusion or
through the natural dispersion of the additive by convection currents
set up by the heat of the projector lamp and by exothermic chemical
reactions that might occur.

Two technical considerations limit the
duration of a light show: when the watch glass fills to overflowing
or when the solution reaches a chemical and hydrodynamic equilibrium.
If the operator is careful in his choice and quantity of additives,
the duration of a light show will not be limited by the opacity of
the solution.

111. CHOICE OF CHEMICALS

Generally, 1 chose materials that
satisfied the following criteria:

(a) When mixed they result in no
compounds that would, through secondary or tertiary products, produce
an explosion, dangerous flames or poisonous fumes.

(b) They have no offensive odor. For
this reason, certain solvents, such as carbon disulfide, are
unsatisfactory. 1 found that certain chemical vapors from the watch
glass combined with the hot products of the gas heater in the room to
produce a very offensive odor. Methyl ethyl ketone was offensive to
some viewers but because of its interesting effects 1 continued to
use it.

(c) They are easily obtainable at a low
price. Certain fluorescent dyes and exotic hydrocarbons were not
chosen for this reason.

1. Starting solutions

The initial component 1 use for the
starting solu-

tion in the watch glass is tap water.
Generally, before turning on the light of the projector, 1 add a
small quantity of a base chemical, for it is easier to make the
solution acid later rather than the reverse.

A starting solution component of
glycerine causes chemical mixing action to be slowed considerably.
Glycerine also creates 'organic' patterns as it is slowly poured into
the watch glass. Some indicators have different dissolving
characteristics in glycerine than in water and acid-base
neutralization occurs much more slowly.

A methanol rather than a tap water
starting component is more effective with many of the acid-base
indicators described below.

2. Acids and bases

The best acid solution 1 found to be
about one part concentrated sulfuric acid to two parts water. This
acid concentration causes the indicators to produce clear colors. If
too concentrated an acid solution is used, then much more of a base
must be added, if it is desired to change colors. The base 1 use is
a 50 per cent saturated solution of sodium hydroxide, stored in a
polyethelene bottle.

If one desires a strong reaction, i.e.
with almost violent spattering in the watch glass, then one can use
concentrated solutions of sulfuric acid and sodium hydroxide. But
one must be very careful, as the heat from this exothermic reaction
can cause a thin watch glass to crack.

3. Indicators and dyes

The use of pH indicators and dyes in a
wet light show has the advantage over the more common use of inks and
water color dyes in that indicators do not become muddy. All inks
and water colors cause the solution to become irreversibly opaque if
too much of one or too many are added. Indicators, on the other
hand, often may be bleached with a 30 per cent solution of hydrogen
peroxide.

There are many types of indicators (cf.
Table 1). Many of them react only at the highest or lowest pH
values and, therefore, for light shows are not useful. Many other
indicators do not produce a brilliant color or interesting color
change. A color change from colorless to violet, for example, was
found to be uninteresting. Indicators that have only one color
change were eliminated. The two indicators I mainly used were thymol
blue sodium salt and bromthymol blue. For a time, 1 used a solution
of methyl orange but the color change from red to yellow proved to be
not as interesting as the more variegated thymol blue. 1 prefer
indicators in crystal or powdered form so that they can be thrown
into the watch-glass solution.

TABLE 1. INDICATORS USED WITH A
METHANOL STARTING

SOLUTION

Acridine orange Congo
red

Alizarin Eosin

Basic fuchsen Fuchine
(acid)

Brilliant green
Fluorescein

Bromcresol green
Malachite green

Bromcresol purple
Methylene blue

o-Cresolsulfonphthalein
Phenolphthalein

Crystal violet

Thymol blue in a base solution is blue
in color; between a pH of about 2-8 and 8-0 it is red, and in a
strongly acid solution it is yellow. It costs around $1.20 per g but
the effects produced are well worth the expense.

Generally, 1 used only thymol blue and
bromthymol blue in solution form. Approximately 0-25 g quantities of
indicator were used per liter of tapwater. This concentration, far
more concentrated than a chemist would use, is effective for wet
light shows.

Congo red is a good indicator of
brilliant red color. The powder, when judiciously thrown into the
solution, makes very tiny dots as it slowly dissolves. If the surface
of the solution is blown upon, the dye will create numerous red
trails. Congo red turns purple or green under certain acid-base
conditions.

Crystal violet is a particularly good
dye and was used extensively. Not only are the crystals easy to
throw into the solution but they dissolve very evenly. The trails
they develop are very much like the congo red, except that crystal
violet gives a thicker trail. Crystal violet has an interesting
reaction with ethylene dichloride; it speeds around the inside of an
ethylene dichloride bubble, spinning off a violet trail until it
colors the entire bubble. If the crystal finds its way to the edge of
the bubble, the crystal will spin around the edge of the bubble at
high speed, ejecting lines of violet color into the surrounding
solution and often pushing the bubble through the solution.

Potassium permanganate is a crystal
with fairly good dissolving properties. A reddish-purple color grows
slowly around the potassium permanganate crystal in the watch-glass
solution. Moreover, in the presence of organic chemicals the color
changes to red.

Gentian violet and aniline blue were
also successfully used.

4. Solvents

Solvents with a high vapor pressure,
such as methyl ethyl ketone (MEK) and methanol have the effect of
agitating the surface of the watch-glass solution. Judiciously
adding MEK to the base side of a solution consisting of sodium
hydroxide, thymol blue and sulfuric acid will cause the creation of a
fire-like effect on the screen, with the blue changing to yellow and
red on the perimeter of the agitating and evaporating MEK. Methanol
has virtually the same effect and can be used alternately with MEK in
order to change some indicator colors or to cause opaque benzene
clouds to become more rapidly translucent.

Solvents ents such as benzene, carbon
tetrachloride, toluene and ethylene dichloride are all virtually
immiscible with water but they each react differently with the
indicator dyes and with each other. Toluene and benzene float on top
of the water and spread out thinly and evenly over a large area.
Crystal violet thrown on benzene will break the surface tension of
the benzene and partially dissolve. Although benzene is transparent
on the surface of the solution, except for distortion on the edges,
adding MEK or methanol will cause benzene to turn a

Ethylene dichloride Carbon
tetrachloride

Solution

Watch glass

Fig. 6.

cloudy opaque white. The agitating
surface causes the benzene cloud to create opaque moving shapes on
the screen. The cloud will become translucent after a period of
time. Crystal violet thrown on the opaque cloud will help it to
become more translucent faster.

Carbon tetrachloride sinks to the
bottom of the solution and, if rapidly poured or infused into the
solution, will form bubbles which eventually join together at the
lowest point of the watch glass. If a smaller amount of ethylene
dichloride is gently added to the solution, ethylene dichloride will
join the carbon tetrachloride but will not mix with it. The
projected effect is of concentric bubbles. Enough ethylene
dichloride must be added so that the chemical breaks through the
surface of the solution, for it is the surface tension of the
chemical which prevents the mixture (cf. Fig. 6). Crystal violet
thrown into the exposed surface of ethylene dichloride may break the
surface tension and cause the inside bubble to vanish.

5. Ways of producing additional effects

A strip consisting of colored
theatrical gels taped together was used to create special effects.
When the strip was slowly drawn across the lens' aperture, the color
content of the projected image was continuously changed.

Experiments with different shapes and
sizes of lass crystals were performed but the effects were lessened
rather than heightened by their use. Distortion seemed to be the
main effect and, as clarity was the sought after effect, crystals
were rarely used. Beck kindly offered the use of his moire patterns
but as these did not blend with the primarily organic' patterns of
the light show, they were not used [2]. , Other effects produced by
mechanical means were found to be satisfying. Siphoning a mixture
from the watch glass produced interesting patterns. At the
conclusion of a show in which much acid and base had been used,
siphoning most of the solution from the watch glass and letting the
remainder evaporate naturally, often produced interesting
image-producing crystals of sodium sulfate.

IV. CONCLUSIONS

I certainly have not tried all
combinations of effects possible in a chemical light show. But I
have tested enough effects to demonstrate the range of possibilities
using a limited number of simple chemicals. Undoubtedly, the range
of effects could be increased by finding materials with other
properties and by resorting to other mechanical means. And, no
doubt, given the right combination of chemicals, techniques and
setting, an imaginative operator may truly produce visual experiences
of the greatest variety for the pleasure and relaxation of
spectators.

REFERENCES

1. F.J.Malina, Kinetic Painting:
The Lumidyne System, Leonardol, 25(1968).

2. B. Beck, Light Show Manual (Los
Angeles: Pericles Press, 1966).

3. C.Jung, Psychologie und Alchemie
(Hamburg:1957).

 

*Amateurs should be warned of the
hazards involved in the use and handling of chemicals. Strong acids
and bases are caustic, may cause stains and severe burns. The
organic solvents used here are all considered highly inflammable and
many have poisonous vapors. Light shows of this type should always
be performed in well-ventilated rooms. We always prohibited smoking
during light shows.

**Artist-systems analyst living at 300
Corral Canyon Road, P.0. Box 455, Malibu, Calif. 90265, U.S.A.
(Received 16 December 1968.)