Wednesday, 6 June 2012

Elephant No. 248: Glow Bands

I've never worn nor played with glow sticks or glow bands, but I thought it might be interesting to see what would happen if I strung a bunch of glow bands together to make an elephant.

The ubiquitous glow sticks seen at concerts, raves and other celebrations started life as lighting devices for the United States Navy. The original Packaged Chemiluminescent Material was patented in 1965 by Bernard Dubrow and Eugene Guth, and by the early 1970s a number of devices had been developed using this material.

The earliest forms of glow stick were conceived as a non-flammable form of emergency flare. The original concept involved the suspension of a glass ampoule inside a plastic tube of liquid. When the glass ampoule was broken, the material inside the ampoule and the liquid in the tube would mix, giving off a bright glow. This is the basic principle behind most glow sticks sold today.

Glow sticks give off light due to a chemical reaction. The plastic outer tube contains a fluorescent dye and something called diphenyl oxalate. The thin glass vial suspended in the tube is filled with hydrogen peroxide. When the glass vial is snapped, the two substances mix, causing a rapid decomposition of the chemicals into carbon dioxide. This releases heat energy that activates the fluorescent dye, which then gives off photons, or light molecules. The colour of the light depends on the chemical composition of the dye. As one source suggests, a glow stick is essentially a portable, self-contained chemistry experiment.

How a glow stick works. 1: A plastic tube encases the
main solution, which is made up of 3: diphenyl
oxalate and fluorescent dye. 2: A glass vial containing
hydrogen peroxide is suspended in the plastic tube. 4: The
hydrogen peroxide vial is snapped. 5: Mixture of the
two solutions causes the stick to glow.

The light in a glow stick can last a few minutes or many hours, depending on the compounds used. If the solutions are heated, the extra heat energy will speed up the reaction, and the stick will glow brighter, but will also burn itself out much more quickly. By the same token, if you cool the glow stick, the reaction will slow down, and the light will become dimmer. For those who want to preserve their glow sticks for an extra day, the stick can be put in the freezer. This won't stop the process entirely; it will, however, extend the reaction for several more hours.

The glow stick on the left has been activated and left at room temperature. The stick
on the right has been activated, then placed in scalding hot water for one minute.
Photo: ©2001 How Stuff Works

Glow sticks essentially demonstrate the principle of luminescence in action. Luminescence is any emission of light not caused by heating. This includes neon lights, televisions, and glow-in-the-dark paint, as well as the bioluminescence of fireflies and many sea creatures.

Bolinopsis infundibulum.
Photo: OAR/National Undersea Research Program (NURP)

Since their invention, glow sticks have been used for many different purposes. There have many advantages: they don't need batteries, are waterproof, give off very little heat, are inexpensive, and can tolerate high pressures, such as those found underwater. As a result, glow sticks are used as both light sources and light markers by night divers, the military, campers and hikers. They are also used as lures in night fishing, and of course at parties, festivals and concerts. Interestingly, glow sticks are the only type of light source considered safe for use immediately after a tornado, earthquake or hurricane, because they don't need electricity, and don't require a spark.

In addition to the above uses, glow sticks are brandished by conductors of marching bands during night performances, and are carried by trick-or-treaters on Hallowe'en. They are popular features of festivals around the world, and are sometimes borne aloft on balloons. Low-light photography and film sometimes include glow sticks to create special effects, and spooky attractions such as Nyctophobia on Long Island sometimes offer visitors glow sticks to provide limited light in a pitch-black environment. The largest glow stick to date, measuring 2.5 metres (8.33 feet) in height, lit up opening ceremonies at the Bang Face Weekender in Sussex, England in April 2009.

For today's elephant, I bought three tubes of "glow bands" from a discount store for a total of about four dollars. Each contains 12 bands and connectors, which I thought would give me enough to play with.

Since I'd never handled one of these before (shocking, I know), I started by bending and shaking one of the glow bands to see what they do. While the glow is pretty, I didn't love the way some of the liquid gaps and bubbles. Oh well. Maybe it won't matter in the dark.

Next, I fiddled with turning these into an elephant. Obviously I couldn't break them or cut them, although this happened a couple of times by accident when I bent them too far. And the plastic is very springy. This made forming a self-contained elephant rather challenging. I thought about making a wire form, then decided that I really wanted to make something that stood alone. Easier said than done.

I folded them until they oozed vinegary glow-in-the-dark liquid. They sprang back. I curved them and connected them in complicated shapes. They popped apart, then sprang back. I wound rubber bands around various parts, but the rubber bands showed as thick lines. I tied on bits of fine thread. Which broke. I was about to admit defeat and try something else for today's elephant, then decided to lower my expectations.

Using fine fishing line, I bound strategic areas of the glow bands together. I also gave up on folding them, except at the tip of the trunk. And I decided to work flat, so that I could just lay two glowsticks on top for a tusk, rather than try to bind them in place somehow. My mind just wouldn't wrap itself around the idea of rigging a tusk to the rest of the head.

This was my final prototype in daylight. It was about a metre (1.25 yards) from the tip of the trunk to the back of the ear, so I put it on my front porch. Because the glow bands were not likely to still be glowing by the time it gets dark, I needed to reproduce this as the sun was going down.

I didn't love working with these to make a representational shape, but I did like the pretty colours and soft glow. If I were to try this again, I would definitely make a sturdy form, and just tie glow bands to the form with fishing line. But we won't hold our breath.

Elephant Lore of the Day
Elephants in various parts of the world have learned to become accomplished night raiders, largely to avoid running into humans. Humans have also adapted, however, and in many areas there are night patrols to keep an eye out for large nocturnal crop thieves.

As you'll see in the video below, this can be a chaotic and very dangerous activity. Sighting elephants with night vision goggles, patrols leap down from watchtowers, armed with flashlights, flares and firecrackers. Based on the belief that elephants are sacred and should not be harmed, the idea is to chase the elephants back into the bush, rather than kill them. What results is nothing short of anarchy as people charge off after elephants in the pitch black, with panicked elephants running in all directions.

On a moonless night, the elephants can only be seen with night vision goggles and the faint light of flashlights—as well as brief bursts of light from flares and fireworks—making it virtually impossible to know where the elephants are. As the video commentator notes, 19 people had been killed by elephants in this one region within a single year—often, no doubt, from being inadvertently trampled in the dark.

To Support Elephant Welfare
Elephant sanctuaries (this Wikipedia list allows you to click through to information
on a number of sanctuaries around the world)
Wildlife Trust of India

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