Jacob Mainzer (1803-1875) was born in Prussia and trained on the Continent. His brother Joseph (1801-1851) was a cleric and educator who developed the “Mainzerian System” of singing, also known as “Singing for the Million.” The system gained some popularity in England and Australia, but also received criticism. His publication “Mainzer’s Musical Times” was the basis for Novello’s “The Musical Times.” Jacob, an adherent of the system, taught in London and became conductor of the South London Choral Society (founded by his brother) and the Amphionic Society in London. Both were significant figures in the popularization of singing in Great Britain. He died in Camberwell, London.