Hundreth (for Hundredth)

Michel Eugène Chevreul was a famous French chemist who specialized in fatty acids (including margaric acid, the precursor to margarine), formulated an early type of soap, and was a pioneer in the field of gerontology. Chevreul himself was a centenarian (plus two), having been born in 1786 and died in 1889. He made it through the French Revolution and lived long enough to see his name engraved upon the Eiffel Tower. Since frequent hand-washing is one of the best ways to stay healthy and live a long life (although most people, notoriously including obtetricians and surgeons, of whom there were several in Chevreul's family, apparently didn't realize it back then), it seems he may have been on to something with all that soap. His own longevity, however, allowed him to pursue a multitude of other interests as well. He did research into various color phenonmena, including what's known as "simultaneous contrast" as well as something called Chevreul's illusion,"the bright edges that seem to exist between adjacent strips of identical colors having different intensities." He was also a professional skeptic and tireless debunker of all manner of 19th-century charlatans. There were 196 cases of Hundreth in OhioLINK today, and "too many records found for your search" in WorldCat. I suspect a number of these may reflect early/variant spellings or cases where it's spelled that way on the piece itself, so be careful when making any corrections here.

(Chevreul in his hundredth year, 1886-1887, Popular Science Monthly, vol. 30, from Wikimedia Commons.)

Carol Reid