CHRISTOPHER, a German Jesuit, born Clavius born at Bamberg, excelled in the knowledge of the mathematics, and was one of the chief persons employed to rectify the calendar; the defence of which he also undertook against those who censured it, especially Scaliger. He died at Rome in 1612, aged 75. His works have been printed in five volumes folio; the principal of which is his Commentary on Euclid's Elements.