How soap came to be discovered is unclear, but we know that the Sumerians were using soap solutions by 3000 BC.
[The Sumerians] used a slurry of ashes and water to remove grease from raw wool and cloth so that it could be dyed. Sumerian priests and temple attendants purified themselves before sacred rites, and in the absence of soap, they too probably used ashes and water.
The slippery solutions clean because the alkali reacts with some of the grease on an object and converts it into soap. The soap then dissolves the rest of the dirt and grease. The more grease and oil dissolved by the alkaline solution, the more soap there is and the better the mixture cleans.
People would inevitably notice this because they used the slippery solutions repeatedly until the solutions lost their potency. Thus, the Sumerians, realising that a little grease improved the performance of the alkali, proceeded to make soap solutions directly by boiling fats and oils in the alkali before using it for cleaning. Specific directions for making different kinds of soap solution have been found on cuneiform tablets.’
– H. W. Salzberg, From Caveman to Chemist, American Chemical Society, Washington DC, 1991
Soaps were not to be found in early Ancient Roman baths; even Cleopatra was confined to essential oils and fine white sand (as an abrasive) for cleansing.
Ancient Roman legend has it that the word ‘soap’ is derived from Mount Sapo, where animals were sacrificed, and from where rainwater washed a mixture of melted animal fats (tallow, a foul-smelling substance also used to make candles) and wood ashes into the River Tiber below. There, the soapy mixture was found to be useful for washing clothing and skin.
By contrast, Pliny the Elder, whose writings chronicle life in the First Century AD, describes soap as ‘an invention of the Gauls for giving a reddish tint to the hair’. He even gives recipes for making soap, indicating that it was used ‘to disperse scrofulous sores’. It’s difficult to imagine the smell and discomfort associated with its early use.
In the early 17th century, chemists and soap manufacturers began to address the problems confronting the soap industry. Their combined efforts over the next 150 years produced an understanding of the chemistry involved, resulting in greater manufacturing efficiency, a wider variety of more fragrant and colourful solid (and liquid) soaps, and milder soaps for use on the finest lace and linens. The industry thrived.
The Industrial Revolution brought steam-power and mechanical energy, leading to economies of scale and even greater production efficiency under more readily controlled conditions. The combination of better soaps and advances in plumbing, including running water and drainable bathtubs, made bathing the social norm.
In 1853, Gladstone repealed the British tax on soap that had been imposed centuries earlier and the industry flourished. It was made even more profitable by Nobel’s invention of dynamite in the same year: dynamite was made from the explosive nitroglycerine, a chemical derived from glycerine, hitherto a waste product of soapmaking.
In the United States, one company, B. J. Johnson, produced a soap made entirely from palm and olive oils. The soap was popular enough to rename their company after it – ‘Palmolive’ (today’s Palmolive soap is not, however, the same as the original).
Today, soapmaking is a highly competitive, science-led, multibillion-pound industry whose product is a long way from the crude, evil-smelling soap of the Middle Ages – thank goodness!
Pears
In 1789, Cornish barber Andrew Pears opened premises in Soho, London (then a fashionable residential area), for the manufacture and sale of rouges, powders, and other preparations used by the rich to cover up the damage caused by the harsh soaps of the time. Pears was one of the first to recognise the potential of a purer, gentler soap that would be kinder to their fashionable but delicate alabaster complexions.
The upper classes associated tanned faces with the lower orders who worked outdoors. The manufacturing process he perfected, using purer ingredients, paying closer attention to each stage in the process, and adding a delicate perfume of flowers, remains substantially unchanged to this day.
Sunlight
In the 1880s, William Lever leased a chemical works in Warrington, where he experimented with different ingredients to manufacture soap. He settled on a formula of palm kernel oil, cottonseed oil, resin and tallow, and named it Sunlight soap.
It was an immediate success, forcing the company to move to a new and much larger factory by the river Mersey in Cheshire. People were now buying a particular make of soap rather than a type.
Like some other Victorian industrialists, Lever was a philanthropist. He built a model town to house his workers, calling it Port Sunlight after the soap it produced. Port Sunlight went on to develop other products like Lifebuoy carbolic soap, Sunlight soap flakes and Vim, each of which became a household name.