Soap

It is unknown exactly when soap was discovered. Ancient writings suggest it was known to the Phoenicians as early as around 600 B.C., and was used to some extent by the ancient Romans. During these times, soap was made by boiling tallow (animal fat) or vegetable oils with alkali containing wood ashes. This costly method of production coupled with negative social attitudes toward cleanliness made soap a luxury item affordable only to the rich until the late eighteenth century.

Methods of soapmaking improved when two scientific discoveries were made in the late eighteenth and early nineteenth centuries. In 1790, the French chemist Nicholas Leblanc (1742-1806) invented a process for creating caustic soda (sodium hydroxide) from common table salt (sodium chloride). His invention made inexpensive soap manufacture possible by enabling chemists to develop a procedure whereby natural fats and oils can react with caustic soda . The method was further refined when another French chemist, Michel Eugène Chevreul (1786-1889), discovered the nature of fats and oils in 1823. As soap production became less expensive and attitudes toward cleanliness changed, soapmaking became an important industry.