Monday, 3 September 2012

Elephant No. 337: Three-Dimensional Corkboard

I bought a pair of cork tiles a few days ago, with no real idea how I'd use them to make an elephant, so today I thought I'd try to figure it out.

Cork comes from a tree called the Cork Oak (Quercus suber), which is native to northwestern Africa and southwestern Europe. Because it is impermeable and lightweight, it is used in many products, from wine stoppers to flotation devices.

Cork was first examined under a microscope by Robert Hooke during the seventeenth century. Interestingly, the divisions he saw in the material led to his discovery of what he called a "cell"—named for its resemblance to a monk's chamber.

Cork oak in Christchurch Botanic Gardens,
Christchurch, New Zealand.

Cork is harvested from early May to late August, when the cork can be separated from the tree without causing permanent damage. Cork is not harvested from a tree until the tree is at least 25 years old and at least 60 cm (24 inches) in diameter.

The first harvest always results in poor quality, or "male" cork. After this, each tree is harvested approximately every ten years, although it can take as many as 13 years for cork to reach an acceptable thickness. High-quality cork is known as "gentle" cork, and is used for making wine and champagne stoppers. A cork tree lives an average of 200 years.

Harvested cork oaks, Ubrique, Spain, 2008.
Photo: Wavering

There are currently about 2.2 million hectares (5.4 million acres) of cork forest in the world: 32.4% of which is in Portugal, and 22.2% of which is in Spain. Approximately 300,000 tonnes (330,000 tons) of cork is produced each year, 61.3% of which comes from Portugal. In 2011, the Portuguese cork industry alone was worth 806,000,000 Euros (approximately $1.1 billion U.S.).

Although there was some controversy a few years ago about the sustainability of cork production, cork is not only an environmentally friendly industry but also a highly sustainable one. Studies on the carbon footprint of the cork industry in a number of countries have determined that cork is, for example, far and away the most environmentally friendly form of wine stopper: a plastic stopper releases ten times more carbon dioxide, and an aluminum one releases a whopping 26 times more carbon dioxide.

The World Wildlife Federation has also launched a campaign to ensure the long-term survival of cork forests. When cork suddenly fell out of favour for wine stoppers, existing cork forests came under threat. And once cork forests are of no commercial value, they face either abandonment or conversion to other uses. This is a significant problem for species that are specific to cork forests, such as the critically endangered Iberian lynx, the Iberian imperial eagle, and the Barbary deer. As a result, the World Wildlife Federation is currently urging people to ensure that they buy wine and champagne with natural cork stoppers. For more on the importance of cork forests, please click here.

Cork is harvested by workers known as "extractors". Using a very sharp axe, they make two types of cut: a horizontal cut around the trunk at a height of about two or three times the tree's circumference, and several vertical cuts called "rulers" or "openings". Although the cuts require significant force, this is actually a rather delicate operation, because the extractor cannot damage the layer just beneath the commercial cork, or the tree will die.

Wine and champagne are the most lucrative cork products. The stoppers made for wine are often a single piece of cork, whereas the stoppers used in champagne are made of composite granules. Because of cork's spongy cellular structure, the material is easily compressed when inserted into a bottle, expanding to create a tight seal.

Natural cork wine stopper.
Photo: © 2007 David Monniaux

The sheets of cork used in bulletin boards and tiles for walls and floors are a by-product of stopper production. Granules of cork can also be mixed into concrete. Cork is used as well for the joins in woodwind instruments such as the clarinet, for shoes, for the cores of baseballs and cricket balls, in heat shields on spacecraft, and even for a special-issue Portuguese postal stamp.

Portugal's stamp made of cork, issued December 26, 2007.
Made of cork measuring a mere 0.35 mm (0.13 inch) in thickness, it had
a face value of one Euro, and was issued in a limited edition of 230,000.

For today's elephant, I realized that the cork tiles I'd bought were actually rather thin, and that I would have to at least layer them if I were to use them in any way. My first idea was to make a couple of shapes with these, then stick them to an existing board. My other idea was to simply layer one of the tiles over top of the other.

I thought that the tiles had a peel-off backing, since most cork tiles do—and also because the uses listed on the label make it sound like they're peel-and-stick. Sadly, they weren't. This made life a bit more complicated, although not unduly so, since I had double-sided tape on hand.

In the end, I decided it would be interesting to make a small elephant corkboard, using one of the 30 x 30 cm (12 x 12-inch) tiles as a background, and cutting up the other to make a raised design. I've never seen a multi-layer corkboard, so I wasn't sure how well it would work out, but the tiles are cheap, so if it ended up a bust, it would be no great loss.

The hard part was figuring out what kind of design to make. The basic square is rather small, so the design would have to be somewhat minimal.

I sketched something out on paper first.

Because I didn't want one big mass for the design, I then retraced the design into a series of templates.

I traced around the templates onto one of the cork tiles, using a permanent marker.

Once I had all the shapes, I cut them out with a sharp craft knife. I tried cutting off one corner with a pair of sharp scissors, but scissors mangle the cork and cause it to fracture, so I used a craft knife and a self-healing cutting mat for everything. When everything was cut, I laid it out to see how it looked. Because there were marker lines on the original side, I flipped all the pieces over.

When everything was cut out, I placed double-sided tape in various strategic locations on the back of each piece.

I then assembled the whole thing.

To finish this, I'll need to get some kind of board or other backing, and a frame. Unfortunately, it's a holiday here today, so the shops aren't open. I may also switch from double-sided tape to glue, depending upon how well this holds together.

In the end, I was quite happy with my final design. I'm not sure how practical it will be, but it looks interesting, and might end up being a fun place to hang jewellery and the like.

Elephant Lore of the Day
Elephants are quick learners, as the following story attests.

Queenie was an Asian elephant at the Melbourne Zoo in Australia, during the first half of the twentieth century. A gentle and intelligent creature, Queenie gave children rides, ate gently from their hands, and performed various tricks. So popular was Queenie that people would line up for hours, just for a chance to interact with her.

Children would often taunt Queenie as well, holding out food that they would then snatch away from her. Often she would respond by taking them in her trunk and rolling them gently onto the ground.

One day, however, Queenie took a different tack. A group of about 15 schoolboys took turns teasing Queenie, each holding out a hand filled with nuts and fruit. As Queenie reached for the treats with her trunk, they would pull their hands away.

After a while, Queenie moved away and instead approached boys with no food. Holding out her trunk, as soon as they reached out to touch it, she would snatch her trunk away. The rest of boys—who had earlier teased Queenie—moved in more closely, each eager to play this new game with the clever elephant.

Queenie giving rides at the Melbourne Zoo, Royal Park, Melbourne, Australia, 1917.

When all of the boys were within range, Queenie suddenly filled her trunk with the dirty water from her bathing pool and soaked all of the boys with one powerful and well-aimed spray.

Sadly, Queenie's story does not have a happy ending. Many years later, when Queenie had been at the zoo for 40 years, dutifully giving children rides, enduring teasing, and performing tricks, she had had enough. Although generally good-natured, one day in 1944 she trampled her keeper to death. He had been particularly cruel to Queenie just before she turned on him, beating her viciously behind the ears for disobedience.

The man tasked with shooting her was heartbroken. He had also been Queenie's keeper for a time, and declared her one of the loveliest animals with whom he had ever worked. He only agreed because he was the best shot in the zoo, and he wanted her end to be quick and painless. Queenie was 48 years old when she was euthanized.

Her story doesn't end there, however. So popular and iconic was Queenie, that she has since been immortalized in books, including the lovely Queenie: One Elephant's Story by Corinne Fenton, with illustrations by Peter Gouldthorpe.

Cover of Queenie: One Elephant's Story, 2006.

To Support Elephant Welfare

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