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Flourens, Pierre

(Encyclopedia)Flourens, Pierre (Marie Jean Pierre Flourens) pyĕr flo͞oräNsˈ [key], 1794–1867, French physiologist. He demonstrated the respiratory center in the medulla and the function of the cerebellum in m...

Haavelmo, Trygve

(Encyclopedia)Haavelmo, Trygve trügˈvə hävelmō [key], 1911–99, Norwegian economist. In the 1940s, he was a pioneer in the field of econometrics, using mathematics and statistics in the formation of economic ...

New Red Sandstone

(Encyclopedia)New Red Sandstone, name for the thick red layer of the Triassic formation in Great Britain (see Triassic period). It is many thousands of feet thick and is composed chiefly of red sandstones, clays, a...

geology

(Encyclopedia)geology, science of the earth's history, composition, and structure, and the associated processes. It draws upon chemistry, biology, physics, astronomy, and mathematics (notably statistics) for suppor...

Hofmeister, Wilhelm

(Encyclopedia)Hofmeister, Wilhelm vĭlˈhĕlm hōfˈmīˌstər [key], 1824–77, German botanist. Although self-taught, he made such valuable studies of the reproduction and development of plants that he was appoin...

lobefin

(Encyclopedia)lobefin, common name for any of a group of lunged, fleshy-finned, bony fishes, also called crossopterygians, that were dominant in the Devonian period and may have given rise to amphibians. They had h...

ginkgo

(Encyclopedia)ginkgo gĭngˈkō [key] or maidenhair tree, tall, slender, picturesque deciduous tree (Ginkgo biloba) with fan-shaped leaves. The ginkgo is native to E China, where it was revered by Buddhist monks an...

Sedgwick, Adam

(Encyclopedia)Sedgwick, Adam, 1785–1873, English geologist. He was a professor at Cambridge from 1818. His most important work was a study, made with R. I. Murchison, of the rock formation of Devonshire, which th...

antacid

(Encyclopedia)antacid, any one of several basic substances that counteract stomach acidity (see stomach). Antacids are used by physicians to treat hyperchlorhydria, i.e., the excessive production of hydrochloric ac...

Bedford, John of Lancaster, duke of

(Encyclopedia)Bedford, John of Lancaster, duke of, 1389–1435, English nobleman; third son of Henry IV of England and brother of Henry V. At the death (1422) of his brother and succession of his 9-month-old nephew...