How hardness is measured

Ancient India gave the world its number system, anticipated Galileo’s heliocentric theory by a millennium and spread its culture from Egypt to Siberia–only to be almost entirely forgotten. It’s past time to restore it to its rightful place in history

Get to grips with groundwater and discover where it comes from

Learn the science behind digging a giant hole.

Across centuries and cultures, clay has been baked, coloured and finished with heat-bonded coatings to create tiles – and the ancient techniques used to produce these durable, decorative claddings are being preserved by artisan studios today

Long known for their hardwearing qualities, tiles also offer myriad design opportunities. There are plenty of options to suit every project and style ambition, offering scope for individuality and int

Well, not quite – but it’s true that about 80 per cent of our ocean floor remains unexplored and uncharted. Discovering what our ocean depths look like and what life might be found there is just as ch