Penny le Couteur & Jay Burreson (47 page)

The economic value of olive oil was readily apparent. City-states became centers of commerce. Large ships, powered by sail or oars and built to carry hundreds of amphorae of oil, traded throughout the whole Mediterranean Sea, returning with metals, spices, fabrics, and other goods available from far-flung ports. Colonization followed trade, and by the end of the sixth century B.C. the Hellenic world had expanded well beyond the Aegean: to Italy, Sicily, France, and the Balearic Islands in the west, around the Black Sea to the east, and even to coastal Libya on the southern shores of the Mediterranean.

But Solon's method of enhancing the production of olive oil had environmental consequences that are still apparent in Greece today. The woodlands that were destroyed and the grains that were no longer planted had fibrous root systems that had drawn water from near the surface and had served to hold the surrounding earth together. The long taproot of the olive tree drew water from layers deep below the surface and had no binding effect on the topsoil. Gradually springs dried up, soil washed away, and the land eroded. Fields that once grew cereals and slopes that bore vines could no longer support these crops. Livestock became scarce. Greece was awash in olive oil, but more and more other foodstuffs had to be imported—a significant factor in governing a large empire. Many reasons have been given for the decline of classical Greece: internal strife among warring city-states, decades of war, lack of effective leadership, the collapse of religious traditions, attacks from outside. Maybe we can add another: the loss of valuable agricultural land to the demands of the olive oil trade.

Olive oil may have been a factor in the collapse of classical Greece, but around the eighth century A.D. the introduction of a product from olive oil, soap, may have had even more important consequences for European society. Today soap is such a common item that we don't recognize what a significant role it has played in human civilization. Try to imagine, for a moment, life without soap—or detergents, shampoos, laundry powders, and similar products. We take for granted the cleaning ability of soap, yet without it the megacities of the present day would hardly be possible. Dirt and disease would make living hazardous under such conditions and maybe not even viable. The filth and squalor of medieval towns, which had far fewer inhabitants than today's big cities, cannot be blamed entirely on lack of soap, but without this essential compound maintaining cleanliness would have been extremely difficult.

For centuries humankind has made use of the cleansing power of some plants. Such plants contain saponins, glycosidic (sugar-containing) compounds such as those from which Russell Marker extracted the sapogenins that became the basis for birth control pills, and the cardiac glycosides like digoxin and other molecules used by herbalists and supposed witches.

Plant names like soapwort, soapberry, soap lily, soap bark, soapweed, and soaproot give a clue to the properties of the diverse range of saponin-bearing plants. These include members of the lily family, bracken, campions, yuccas, rues, wattles, and the genus
Sapindus.
Saponin extracts from some of these plants are still used today to wash delicate fabrics or as hair shampoos; they create a very fine lather and have a very gentle cleansing effect.

The process of making soap was most probably an accidental discovery. Those cooking over wood fires might have noticed that fats and oils that dripped from the food into the ashes produced a substance that formed a foamy lather in water. It would not have taken long to realize that this substance was a useful cleaning agent and that it could be deliberately manufactured using fats or oils and wood ash. Such discoveries no doubt occurred in many parts of the world, as there is evidence of soap production from many civilizations. Clay cylinders containing a type of soap and instructions for its manufacture have been found in excavations from Babylonian times, nearly five thousand years ago. Egyptian records dating from 1500 B.C. show that soaps were made from fats and wood ash, and through the centuries there are references to the use of soap in the textile and dyeing industries. The Gauls are known to have used a soap made from goat fat and potash, to brighten or redden their hair. Another use of this soap was as a type of pomade to stiffen hair—an early hair gel. The Celts have also been credited with the discovery of soap making and for using it to bathe and to wash clothes.

Roman legend attributes the discovery of soap making to women washing clothes in the Tiber River downstream from the temple on Mount Sapo. Fats from animals sacrificed at the temple combined with ashes from sacrificial fires. When it was raining, these wastes would run down the hill and enter the Tiber as a soapy steam, which could be used by the washerwomen of Rome. The chemical term for the reaction that occurs when triglycerides of fats and oils react with alkalis—from ashes—is
saponification,
the word derived from the name of Mount Sapo, as is the word for soap in a number of languages.

Although soap was manufactured in Roman times, it was mainly used for washing clothes. As with the ancient Greeks, personal hygiene for most Romans usually involved rubbing the body with a mixture of olive oil and sand, which was then removed with a scraper made especially for this purpose and known as a strigil. Grease, dirt, and dead skin were removed by this method. Soap gradually came to be used for bathing during the later centuries of Roman times. Soap and soap making would have been associated with the public baths, a common feature of Roman cities that spread throughout the Roman Empire. With the decline of Rome, soap making and soap using appears to have also declined in western Europe, although it was still made and used in the Byzantine Empire and the Arab world.

In Spain and France during the eighth century there was a revival of the art of soap making, using olive oil. The resulting soap, known as “castile” after a region of Spain, was of very high quality, pure, white, and shiny. Castile soap was exported to other parts of Europe, and by the thirteenth century Spain and southern France had become famous for this luxury item. The soaps of northern Europe were based on animal fat or fish oils; the soaps they produced were of poor quality and were used mainly for washing fabric.

The chemical reaction for making soap—saponification—breaks a triglyceride into its component fatty acids and glycerol through the use of an alkali, or base, such as potassium hydroxide (KOH) or sodium hydroxide (NaOH).

Potassium soaps are soft; those made with sodium are hard. Originally most soaps would have been potassium soaps, as wood ash from burning timber and peat was the most readily available source of alkali. Potash (literally, the ashes from a fire pot) is potassium carbonate (K
₂
CO
₃
), and in water forms a mildly alkaline solution. Where soda ash (sodium carbonate, Na
₂
CO
₃
) was available, hard soaps were produced. A major source of income in some coastal regions—Scotland and Ireland in particular—was collecting kelp and other seaweeds, which were burned to make soda ash. Soda ash dissolved in water also produces an alkaline solution.

In Europe the practice of bathing declined along with the Roman Empire, although public baths still existed and were used in many towns until late in the Middle Ages. During the plague years, starting in the fourteenth century, city authorities began closing public baths, fearing that they contributed to the spread of the Black Death. By the sixteenth century bathing had become not only unfashionable but was even considered dangerous or sinful. Those who could afford it covered body odors with liberal applications of scents and perfumes. Few homes had baths. A once-a-year bath was the norm; the stench of unwashed bodies must have been dreadful. Soap, however, was still in demand during these centuries. The rich had their clothes and linens laundered. Soap was used to clean pots and pans, dishes and cutlery, floors and counters. Hands and possibly faces were washed with soap. It was washing the whole body that was frowned upon, particularly naked bathing.

Commercial soap making began in England in the fourteenth century. As in most northern European countries, soap was made mainly from cattle fat or tallow, whose fatty acid content is approximately 48 percent oleic acid. Human fat has about 46 percent oleic acid; these two fats contain some of the highest percentages of oleic acid in the animal world. By comparison, the fatty acids in butter are about 27 percent oleic acid and in whale blubber about 35 percent. In 1628, when Charles I ascended to the throne of England, soap making was an important industry. Desperate for a source of revenue—Parliament refused to approve his proposals for increased taxation—Charles sold monopoly rights to the production of soap. Other soap makers, incensed at the loss of their livelihood, threw their support behind Parliament. Thus it has been said that soap was one of the causes of the English Civil War of 1642-1652, the execution of Charles I, and the establishment of the only republic in English history. This claim seems somewhat far-fetched, as the support of soap makers can hardly have been a crucial factor; disagreements on policies of taxation, religion, and foreign policy, the major issues between the king and Parliament, are more likely causes. In any event, the overthrow of the king was of little advantage to soap makers, since the Puritan regime that followed considered toiletries frivolous, and the Puritan leader, Oliver Cromwell, Lord Protector of England, imposed heavy taxes on soap.

Soap can, however, be considered responsible for the reduction in infant mortality in England that became evident in the later part of the nineteenth century. From the start of the Industrial Revolution in the late eighteenth century, people flocked to towns seeking work in factories. Slum housing conditions followed this rapid growth of the urban population. In rural communities, soap making was mainly a domestic craft; scraps of tallow and other fats saved from the butchering of farm animals cooked up with last night's ashes would produce a coarse but affordable soap. City dwellers had no comparable source of fat. Beef tallow had to be purchased and was too valuable a food to be used to make soap. Wood ashes were also less obtainable. Coal was the fuel of the urban poor, and the small amounts of coal ash available were not a good source of the alkali needed to saponify fat. Even if the ingredients were on hand, the living quarters of many factory workers had, at best, only rudimentary kitchen facilities and little space or equipment for soap making. Thus soap was no longer made at home. It had to be purchased and was generally beyond the means of factory workers. Standards of hygiene, not high to start with, fell even lower, and filthy living conditions contributed to a high infant death rate.

At the end of the eighteenth century, though, a French chemist, Nicolas Leblanc, discovered an efficient method of making soda ash from common salt. The reduced cost of this alkali, an increased availability of fat, and finally in 1853 the removal of all taxes on soap lowered the price so that widespread use was possible. The decline in infant mortality dating from about this time has been attributed to the simple but effective cleansing power of soap and water.

Soap molecules clean because one end of the molecule has a charge and dissolves in water, whereas the other end is not soluble in water but does dissolve in substances such as grease, oil, and fat. The structure of the soap molecule is
and can also be represented as