50, 100 & 150 YEARS AGO.

Dr. Osborn classifies it as a new species and genus and names it Hesperopithecus haroldcookii, which means 'the anthropoid from the west discovered by Harold Cook'. INNOVATION AND DISCOVERY AS CHRONICLED IN SCIENTIFIC AMERICAN Compiled by Mark Fischetti SCIENTIFIC AMERICAN ONLINE FIND ORIGINAL ARTICLES AND IMAGES IN THE SCiENTiFiCAMERiCAN ARCHIVES AT scientificamerican.com/magazine/sa 1973 Catalytic Conversion "Among the most troublesome air pollutants produced by automobiles are the chemically active nitrogen oxides. The process consists of spraying the clouds from an airplane with electrically charged sand, clearing away the cloud and producing an incipient rainstorm. [Extracted from the article]

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