a chemist and surgeon navid nicolas lablanc patented a soap-making in 1791.ungarian physician was the first to really push hand disinfection. >> you and i have a coat of armour that protects our bodies from the outside world. >> reporter: in the commercial soap we used to emerged in the 1900s, a process called batch kettle boiling. it was introduced, refined and sold to the nation by a still-growing industrial giant, procter & gamble. soap is nothing more than the salt of a fatty acid. it works because it breaks up oil and germs into small drops, which can be easily washed away. >> you, yes you, will love gentle ivory soap in this handy personal size. >> reporter: during and after world war ii, soap sponsorships of radio and tv serials in america became so common, people started calling them soap operas. >> the new wonder bar, camay. >> you make your own lye soap? >> got to. you can't buy it in beverley hills. >> reporter: later thereas granny's lye soap in berley hill billies. >> some possum renderings. >> enough soap would blow up just about anything. >> re