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The Natural History Museum, London
Voyages online
1872 - Challenger & the deep ocean
Specimens in alcohol Challenger's voyage dredged tonnes of mud from the seabed, all over the world. This was sorted, stored and later studied. Among their discoveries was that large areas of the deep sea floor are littered with manganese nodules. These are rich in copper, nickel and cobalt and are potentially a valuable resourse. Challenger also proved that life existed on the seabed - a conclusion thought unlikely by the majority of scientists only a few years before the voyage.
Metoerite material
But it was also the first time that material from space was positively identified. Tiny particles recovered from sediment were believed to be extraterrestrial because their magnetism indicated iron, and were thought to be parts of larger meteorites that split off during passage through the Earth's atmosphere. However, recent study indicates that they were actually already tiny when they entered the atmosphere - having formed from extraterrestrial dust from comets and asteroids.

1687 - Sloane in Jamaica 1831 - Darwin in South America 1848 - Wallace in South America & Malay 1872 - Challenger & the deep ocean