PROF. GREGORY is to be congratulated on having found, or made, opportunity to complete his work in East Africa, begun so brilliantly and adventurously in 1892–3. Returning to the country for a short ...
Geologists say the Great Rift Valley was formed by the Earth's tectonic plates pulling away from each other, about 30 million years ago. The process continues, they say, at about six mm per year, with ...
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