Franz Ernst Brückmann (1697-1753), German mineralogist, was born on the 27th of September 1697 at Marienthal near Helmstädt. Having qualified as a medical man in 1721, he practised at Brunswick and afterwards at Wolfenbüttel. His leisure time was given up to natural history, and especially to mineralogy and botany. He appears to have been the first to introduce the term oolithus to rocks that resemble in structure the roe of a fish; whence the terms oolite and oolitic. He died at Wolfenbüttel on the 21st of March 1753. He published Magnalia Dei in locis subterraneis (Brunswick, 1727), Historia naturalis curiosa lapidis (1727), and Thesaurus subterraneus Ducatus Brunsvigii (1728).