The science of sandcastles
Thought building sandcastles was child's play? Well think again
Children love making sandcastles, it's fun and creative and there's a huge sense of satisfaction showing off their spectacular structures to fellow visitors to the beach. But did you know there's actually a complex science behind sandcastle making? Although sand will stick together effectively if you mix anywhere between one and 20 per cent water by volume with the sand (this is known because German scientists spent many months studying a pile of sand using a special miniature CAT scanner), the optimum ratio is eight times as much sand as you have water. There's even a mathematical formula for it: OW = 0.125 x S. Not that the average child needs to worry too much about ratios, but more serious sandcastle makers undoubtedly do. Indeed it was knowledge of this formula that helped create the world's biggest sandcastle at Myrtle Beach in South Carolina back in 2007. A team of seven "professional sandcastlers" took ten days to mould 300 specially formulated truckloads of sand into a colossal construction, whose pinnacle towered more than 15 metres above the beach. For the less ambitious, here are a few sandcastle building tips:
• Get your child to draw a rough sketch of the castle they would like to build.
• Choose a site near the water, but not too close or the waves will destroy the castle. Make sure the site is large enough for your child's castle plans.
• Help your child dig down to find the moist sand, or get your child to fetch a bucket of water from the sea and use to moisten the sand.
• Scoop the damp sand into the centre of your site and start by building the towers. Help your child do this by forming and stacking sand patties about the size and shape of a thick pancake. Gently shake the patties from side to side as you pile them as this will ensure that the sand settles. To seal the towers, gently pour over a little water and rub in.
• Build walls to connect the towers of the castle, and carve the walls and towers into shape using a spade.
• Dig a moat around the castle to keep out unwanted visitors. Better still, get your child to stand on sentry duty!
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