Reaumur
2 of the 6 encyclopedias on this shelf carry an entry for Reaumur. Both are reproduced below, so you can see where they agree and where they differ.
Aiton's Encyclopedia (1910)
ra-o-mur' (1683-1757), a French scientist. He was educated at the Jesuit College of Poitiers, and settled at Paris in 1703. His scientific acquirements attracted the attention of the learned men of Paris. Five years later he was chosen a member of the Academy of Sciences, of which he continued an active member for half a century. He studied the formation of pearls. He was a learned student of fossils. He proved to the Academy that a peculiar gem, known as the Languedoc turquoise, was the tooth of an extinct animal. He brought an improved method of making steel to the notice of the manufacturers of France. He studied processes of making pottery and invented a new kind of enamel since known by his name. He is best known, however, by the thermometer which bears his name. See Thermometer
Collier's New Encyclopedia (1921)
RENÉ ANTOINE FER- CHAULT DE, a French physicist and naturalist; born in La Rochelle, France, Feb. 28, 1683. He went to Paris in 1703; in 1708 was chosen a member of the Academy of Sciences; and for nearly 50 years continued to be one of its most active members. As a natural philosopher he is celebrated for the invention of an improved thermometer, which he made known in 1873, but his greatest work is "Natural History of Insects" (6 serates vols.). He died in Maine, France, Oct. 18, 1757. REAUMURIACEÆ, in botany, reaumuriads; an order of hypogynous exogens, alliance Guttiferales; small shrubs, with fleshy scale-like exstipulate leaves, covered with resinous sunk glands. From the coasts of the Mediterranean and the salt plains of temperate Asia. Known genera three, species four.
What Has Changed in the Last Century
Both accounts rest Réaumur's fame on his thermometer, and Aiton's simply refers the reader to "Thermometer" — reasonable in 1910, when the 80-degree Réaumur scale (0 for freezing, 80 for boiling) was still in everyday use in parts of Germany, Russia and Italy. It has since vanished from practical life, displaced by Celsius and Fahrenheit, and survives mainly as a curiosity and in a few traditional cheese-making instructions in Italy and Switzerland. What has grown instead is his standing as a naturalist: the "Natural History of Insects" Collier's calls his greatest work — the Mémoires of 1734-42 — is now treated as a founding text of entomology, alongside his experiments on digestion using birds' gastric juices. Note that Collier's date of "1873" for the thermometer is a misprint; he described it around 1730.
Written for this edition, 2026.