	Claude Louis Berthollet	Pyrrhotite Berthollide	Berthollet's Salt	Bertillion System	Alphonse Bertillon
Eugenio Bertini	Bertini's Theorem	Mario Bertolotti	Bertolotti Garcini Syndrome	Joseph Louis François Bertrand	Bertrand Diguet Theorem
Bertrandite	$Émile Bertrand (born: 1844 deceased: 1909) was a French mineralogist, in honour of whom bertrandite was named by Alexis Damour. He also gave his name to the Bertrand lens or phase telescope. He studied at the Ecole des Mines in Paris and was a co-founder of the Société française de Minéralogie. He wrote a book on the application of microscopy to mineralogical studies, ‘De l'Application du microscope à l'étude de la minéralogie’ (1878); published a translation of Ernst Mach's work on the history of mechanics, ‘La mécanique: exposé historique et critique de son développement’ (1904); and is credited with the design of a refractometer.$ Émile Bertrand	Emile Bertrand Lenses	Bertrand's Ballot Theorem	Bertrand's Prime Postulate	Joseph Bertrand Medal
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