First paragraph:
The origin of the term ‘Radical’ can be traced as far back as the early nineteenth century when chemists such as Berzelius, Gay-Lussac and Liebig were tackling the then immense problems presented by the complex structures of organic compounds. Working with hydrogen cyanide, Gay-Lussac and Thenard found that the CN combination could be transferred from compound to compound without its breaking apart into individual carbon and nitrogen atoms. Such a group of two or more atoms that remained in combination while being transferred from one molecule to another was termed a radical from the Latin word for ‘root’. It was believed that organic molecules might be constructed out of a limited number of these ‘roots’.