Complex sentence: He happened to let fall a specimen of calcareous spar which belonged to a friend; examining the fragments, he was led to make experiments which resulted in the statement of the geometrical law of crystallization associated with his name.
Split into simpler sentences: He happened to let fall a specimen of calcareous spar which belonged to a friend. Upon examining the fragments, he was led to make experiments which resulted in the statement of the geometrical law of crystallization associated with his name.