The film darkened in response to some type of energy, which Bequerel assumed to be the prescence of the sun.
However, Becquerel's second experiment revealed something much more interesting.
Thanks to Astronomy Notes reader Katie Cook for locating several of these resources.
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Geology is the study of the composition and physical properties of rocks, minerals, gems and other related earth materials, including diamonds and crystals.
Scientists gain an understanding of the Earth's history by studying its composition.
The story of this great change in the conception of the history of Earth is not a simple one.