How a change in slope affects lava flows

As soon as lava flows from a volcano, exposure to air and wind causes it to start to cool and harden. Rather than hardening evenly, the energy exchange tends to take place primarily at the surface. The cooling ...

11 hours ago 4 / 5 (1) 0

Chinese city creates cellphone sidewalk lane

Taking a cue from an American TV program, the Chinese city of Chongqing has created a smartphone sidewalk lane, offering a path for those too engrossed in messaging and tweeting to watch where they're going.

14 hours ago not rated yet 1