He geography of Canada describes the geographic features of Canada, the world's second largest country in total area.<span> </span>
A barometer, it measures air pressure
Devils tower this was the first national monument in wyoming.
If you could dig a tunnel right through the Earth you could theoretically free-fall to the centre of our planet in just eighteen minutes. You can’t, of course: such a tunnel would have to tolerate temperatures as high as the surface of the Sun and pressures three and a half million times greater than those at the Earth’s surface.
