Here’s how science can help you build the perfect sandcastle

Woo! Image: Getty.

Whether we prefer water sports or relaxing with a good book, the humble sandcastle is often a seaside must. But what’s the secret to building a majestic sandcastle that will withstand the tide of time? Luckily, there’s a scientific formula for that.

It all started back in 2004, when a holiday company asked us to investigate the question. As a sedimentologist, someone who studies fragments of rock, I began pondering what kind of beach would work best for castle building. To find out, I compared the sand from the ten most popular beaches in the UK at the time.

Though in truth any sandy beach will do, Torquay came out top with its delightful red sand, closely followed by Bridlington, with Bournemouth, Great Yarmouth and Tenby tied in third. At the bottom of the league was Rhyl.

Having selected a beach one has to find the perfect spot. Now this is a question of taste rather than hard rules. Some might prefer a spot close to the car park with easy access when the rain arrives, while others might want to stay next to a cafe. Others yet might hanker after the secluded fringes of the beach, perhaps sheltered by natural promontories of rock that keep the biting wind at bay.

Torquay harbour. Image: Averoxus/Wikimedia Commons.

Now a castle should be a symbol of military strength, but to stand proud one needs strong sand. The strength of sand depends on the properties of its individual grains and on the water between them. The more angular the grains, the better they will lock together. The more a grain is transported the more rounded it becomes. Microscopic shell fragments work well in this regard. The finer the grains the more they hold the water. And water matters.

Too much water and your sand will flow, too little and it will crumble. You need to get it just right and your castle will stand proud and last. It’s all down to the surface tension of water – the thing that gives the “meniscus”, or skin, to a glass of water and holds down that glass when placed on a wet bar top. The film of water between individual sand grains is what gives sand its strength, too much and it lubricates one grain over the other, but just right and it binds them strong.

The magic formula

Now the experimentation we did suggested that the perfect sandcastle requires one bucket of water to eight buckets of dry sand. Or if you want the magic formula: Water = 0.125 x Sand. So assuming that you don’t have any science gear with you, then you are looking for a spot close to the high tide line – usually marked by a line of seaweed and flotsam – and the low tide line where sand is still visibly wet and the waves are close. But remember that this will change as the tide comes and goes during the day.

High tide line. Image: author provided.

My next tip refers to quality of your tools. In my experience there is a direct correlation between the age of the builder, spade size and the speed at which boredom sets in. Adult helpers find the smallest spade nothing but frustrating, and while young assistants might aspire to use the biggest spade, it is often too big to handle. A selection of tools will keep the workforce in harmony.

The bucket also has to be the perfect size and shape. The best buckets are the simple round ones – not the ones with the fancy turrets which when turned out produce a castle in itself. A round bucket will allow you turn out countless towers and architectural features. A single bucket can be turned out several times to create a large mound from which you carve an amazing tower.

As you build, spare a thought to the story, not just of the castle one is building with its tales of derring-do, but also the story of the sand itself. Each grain is a fragment of rock and contains a story of relict mountains, ancient rivers, dinosaur-infested swamps and seas, of past climates and events which tell the amazing story of our planet. The red sand of Torquay once blew in giant sandstorms, as the area was once part of a desert far greater than that of the Sahara. The sand at Bridlington or Great Yarmouth tells a tale of giant ice sheets and drowned lands below the North Sea.

The ConversationMy next tip refers to size. Yes, size matters – at least in the game of sandcastles. The modest castle with perfect towers, battlements and moat is okay, but it is the huge castles which break the beach horizon that inspire awe and wonderment in people that pass by. Think big! Pebbles, shells, driftwood fragments and feathers all enhance a castle. And let’s face it: a castle is about being seen. And although there may be science behind the humble sandcastle, don’t forget to have fun building it.

Matthew Robert Bennett is professor of environmental and geographical sciences at Bournemouth University.

This article was originally published on The Conversation. Read the original article.

 
 
 
 

Can you have capitalism without capital? Brighton, Ankara, Ghent and the intangible economy

The Fusebox, Brighton. Image: WiredSussex.

As you head north out of Brighton on the A23 things take a distinctly granular turn. The cool bars and trendy eateries give way to second-hand shops and nail bars.

Looming over the area, New England House, an eight-storey brutalist office block, is home to Wired Sussex, a collection of digital and media companies, as well as its offshoot The Fusebox. Here, a collection of entrepreneurs, tech visionaries and creative technologists are seeking to transform their ideas into successful businesses. This island of cutting-edge thinking, surrounded by the evidence of the glaring consequences of austerity, could stand as a synecdoche for the suddenly vogueish concept of the “intangible economy”.

Towards the end of last year, on Radio 4’s Start The Week, Jonathan Haskel, author of Capitalism Without Capital, laid out the features of this brave new economy. The ideas are scalable, have sunk costs, their benefits spill over, and they have synergies with other intangible assets. All of these things are, to a greater or lesser extent, attributes featured in the virtual reality games, apps for care home workers, and e-commerce ideas mapped out by the bright sparks in the Fusebox.

Its manager, Rosalie Hoskins, explains that it exists to support the work of small companies doing creative work. Within these clean white walls they can bounce their ideas off each other and reap the fruits of collaboration. “We’ll provide the doors,” she says. But “it’s up to them to open them.”

One innovative thinker hoping to make her entrance is Maf’j Alvarez. She tells me she studied for a masters in digital media arts at the University of Brighton, and describes herself as an ‘interactive artist’. “Right now I am playing with virtual reality,” she tells me. “There’s a lot of physics involved in the project which explores weight and light. It definitely has a practical application and commercial potential. VR can be used to help people with dementia and also as a learning tool for young people.”

The Fusebox, she says, is “about collaboration. The residents of the Fusebox are in all a similar situation.”

The willingness to work together, identified by Haskell as a key element of the intangible economy, is evident in the Fusebox’s partnership with like minded innovators in Ankara. Direnç Erşahin from İstasyon, a centre for “social incubation” based in the Turkish capital, visited the Fusebox toward the end of last year.

“It was a good opportunity to exchange knowledge about the practice of running a creative hub – managing the place, building a community and so on,” he says.

Erşahin and his colleagues have launched a fact-checking platform – teyit.org – which he believes will provide “access to true information”. The co-operation between the Fusebox in Brighton and İstasyon in Ankara  is “a good opportunity to reinforce a data-oriented approach and university and society interaction,” he argues.

But the interaction between wider society and the denizens of the intangible world is often marked by friction and, ironically, a failure of communication.

This point is underlined by Aral Balkan, who runs a company called indie.ie which aims to develop ethical technologies. “There’s a good reason we have a trust problem,” he says. “It’s because people in mainstream technology companies have acted in ways that have violated our trust. They have developed systems that prey upon individuals rather than empowering them.”

A former Brighton resident, Balkan is almost a walking definition of Theresa May’s “citizen of nowhere”. He is a regular speaker on the TED and digital circuits, and I crossed paths frequently with him when I covered the industry for Brighton’s local newspaper. He left the city last year, chiefly, he tells me, in protest over the UK government’s overweening “snooper’s charter” laws.


He has Turkish and French citizenship and is now based in Malmö, Sweden, while working with the city of Ghent on a radical redevelopment of the internet. “Ghent is a beautiful example of how location affects the work,” he tells me. “They don’t want to be a smart city, they want to encourage smart citizens. We are exploring alternatives.”

Karl-Filip Coenegrachts, chief strategy officer at the City of Ghent, is another believer in the synergies made possible by the intangible economy. “The historic perspective has impacted on the psychology and DNA of the city,” he says. “The medieval castle built to protect the nobility from the citizens not the other way around. People in Ghent want to have their say.”

Left out of this perspective, of course, are those who cannot make their voice heard or who feel they are being ignored. The fissures are easy to find if you look. The future of Belgium’s coalition government, for example, is threatened by Flemish nationalists in the wake of a scandal over the forced repatriation of 100 Sudanese migrants. In Ankara, President Recep Tayyip Erdogan has purged local government and continues to stamp on any dissent.

In the UK, the gig economy makes headlines for all the wrong reasons. Back in the area around the Fusebox, the sharp observer will notice, alongside the homeless people curled up in sleeping bags in charity shop doorways, a stream of gig-worker bikers zooming from one order to another.

The intangible economy throws up all-too tangible downsides, according to Maggie Dewhurst, vice chair at the Independent Workers Union of Great Britain. She gives short shrift to the idea of ‘capitalism without capital’.

“It does get a bit irritating when they muddy the waters and use pseudo academic definitions. They pretend tangible assets don’t exist or are free.”

In fact, she adds, “The workers are a human resource.”