Encyclopædia Britannica, Ninth Edition/Tourmaline
TOURMALINE.Electricity, vol. xiii. p. 99; Geology, vol. x. p. 228; and Minerology, vol. xvi. p. 409.
From volume XXIII of the work.
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TOURMALINE.Electricity, vol. xiii. p. 99; Geology, vol. x. p. 228; and Minerology, vol. xvi. p. 409.