ont dû se manifester, must hâve been active

Page 99. — 1. Elie de Beaumont; cf. page 88, note 5.

2. Brongniart (1 770-1 847), French geologist and mineralogist, born at Paris. Names of eminent persons may be construed with the definite article in the plural, with the force of, "a Brongniart, a Dufrénoy, etc."

3. Dufrénoy (1 792-1 857), noted French geologist; was the director of the Ecole des mines.

4. Buckland (William, 1784-1856), English geologist, who endeavored to confirm the narrative of Genesis by the discoveries in geology. He was professor of mineralogy and geology at the University of Oxford.

5. Agassiz (1807-1873), the celebrated Swiss naturalist and geologist. After 1848, he made the United States his permanent résidence, having accepted the chair of zoology and geology at Harvard University. He died at Cambridge, Mass.

6. Saussure (1 740-1 799), a Swiss physicist and geologist; became professor of physics and philosophy at the University of Geneva in 1762; made a séries of important geological explorations in the Alps and other mountains, and was one of the first to accomplish the ascent of Mont Blanc (1787).