The slipperiness of ice explained

Winter sports such as skiing, speed skating, figure skating, and curling require the slippery surfaces of ice and snow. While the fact that the ice surface is slippery is widely acknowledged, it is far from being completely understood. In 1886 John Joly, an Irish physicist, offered the first scientific explanation for low friction on ice; when an object - i.e. an ice skate - touches the ice surface the local contact pressure is so high that the ice melts thereby creating a liquid water layer tha...