Until the beginning of the 19th century soap making was more like a cottage industry than an industrial procedure. A large number of soaperies existed throughout Britain and each soapery produced soap on a small scale; indeed some households produced a soap-like material for their own domestic use.
The manufacture of soap goes back for many centuries. It is essentially a simple process. Soap is produced by boiling fat with alkali. Fat was obtained easily in the form of tallow from animals. Alkali was more of a problem. It was usually obtained from the ashes of burnt vegetable matter. Traditionally wood ash was used. This produced 'potash' which when boiled with fat resulted in a soft form of soap. To produce hard soap, other vegetable materials had to be used.
It should be understood that, at the time, the chemistry of soap manufacture was not known. Soap was produced in a traditional manner by methods which had evolved over a long period of time through trial and error. Indeed it was not until 1803, which happened to be the year of foundation of the first successful soapery in Runcorn, that John Dalton outlined his atomic theory, the basis for the new science of chemistry, in a lecture in Manchester. We now know that wood ashes produce a potassium-containing alkali and that an alkali containing sodium is needed for hard soap.
In the late 18th century sodium-containing alkali was obtained for commercial soap-making purposes from two main vegetable sources, the ashes of barilla and of kelp. Barilla was made from a member of the goosegrass family of plants which grew mainly on the shores of the Mediterranean. Kelp was produced from the ashes of seaweed which grew around the coasts of the western Scottish islands and Ireland.
Towards the end of the 18th century the production of alkali from vegetable sources was beginning to cause problems. Its production was very labour-intensive, the material produced was impure and the yield of alkali was very low, of the order of 1 3%. The demand was beginning to outstrip the supply. This was compounded in France by international conflicts which blocked the imports of the substance. The French Academy of Science established a competition to discover a method for the production of alkali by artificial means from sodium chloride, common salt.
The problem was eventually solved in France by Nicholas Leblanc who took out a patent for his method in 1791. The production of alkali from salt by the Leblanc process takes place in two stages. First, salt is heated with sulphuric acid, which produces a substance known as saltcake, which chemically is sodium sulphate. This stage of the process was already in use; sodium sulphate was also known as Glauber's salt and it had medicinal uses. The process of making sulphuric acid in lead chambers for this procedure had been also been in use for some time. What was original for the production of alkali was Leblanc's second stage, which was to heat saltcake with coal or coke and with limestone or chalk. This results in a substance known as white ash. When this is refined, soda (sodium carbonate), an alkaline substance is produced. By this method, alkali could be made artificially by fairly simple means for use in the production of soap.
This was to prove revolutionary, not only for soap manufacture, but also as the basis for what was to become an entirely new industry, the chemical industry. Indeed the artificial production of alkali by the Leblanc process was to prove important for other industries, industries which were larger than the soap-manufacturing industry, those industries which were to play a major role on the development of the Industrial Revolution. The biggest of these was the textile industry where bleaching powder, which was synthesized from soda, solved a problem. The use of this substance replaced the labour-intensive and time-consuming need to bleach cloth by exposing it to the sun. Alkali was also a vital material in the paper and glass making industries. The necessary alkali for these industries was made mainly by the soap makers who produced more than they required for their own purposes and sold it on to them. As time passed, factories concentrating only on producing alkali by the Leblanc process were founded. These factories formed the basis for the chemical industry which developed in Runcorn and Widnes, elsewhere in the Mersey valley, and further afield.
While the Leblanc process had beneficial effects in the production of chemicals for use in various industries and in the creation of profit for these industries, it also had considerable harmful effects. Its major disadvantage was environmental pollution. In addition to the production of smoke from the burning of coal, the procedure produced as by-products various evil-smelling sulphur-containing substances. And worst of all was the production of hydrochloric acid. This was produced as a gas which is heavier than air and which is lethal to all living things. It kills all plants with which it comes into contact and will kill animals if they inhale a sufficient quantity of it. In the early days of the Leblanc process there was no known use for hydrochloric acid and no convenient way to get rid of it. Many years later, it was to be rendered less harmful by passing it through the absorption towers devised by Gossage, and also many years later, a process was discovered to make chlorine from it. But in the earliest days the gas was just allowed escape with the smoke up relatively low chimneys. In time, very high chimneys were built to disperse the pollutants, in the hope that by the time the hydrochloric acid reached the ground, it would be sufficiently dilute to be relatively unharmful.
In Runcorn, the first successful business to be established to make soap, and later alkali, was founded by an entrepreneurial businessman, John Johnson, in 1803. This business prospered and in 1816 another soap-making business, which was to become a major although a somewhat smaller concern, was established by another entrepreneur, Thomas Hazlehurst. Attempts were made by others to compete with Johnson's and Hazlehurst's, but in time these came to nothing.
Runcorn was ideally placed geographically to become a centre for soap making, and for using the Leblanc process for the manufacture of alkali. Its waterway links provided both a means for transporting the necessary raw materials to the factories and the finished products, soap and chemicals, away from the factories. Both of the major Runcorn soap-making businesses, Johnson's and Hazlehurst's, were established on the sides of the Bridgewater canal. This canal had connections inland with the Derbyshire limestone quarries. Along the nearby Weaver Navigation system came salt from the mid-Cheshire salt mines. Runcorn docks provided a connection with the Mersey river and estuary. From across the Mersey, coal could be transported from the Lancashire coalfields via the Sankey canal. The Mersey estuary gave access to the coastal ports of Great Britain and, beyond that, to the Irish Sea and to world markets. Through Runcorn docks came limestone from North Wales and, in the earlier days, kelp from Ireland and the Scottish islands. Later, sulphur for the manufacture of sulphuric acid arrived. This would be either in its elemental form from Sicily, or in the form of pyrites from mines in Ireland and further afield. When tallow was replaced by vegetable oils as the fat used for the soap-making process, palm oil and cocoanut oil were imported via Liverpool through Runcorn docks.
At the time that the Runcorn firms started to make soap, it was subject to an excise duty of three pence for each pound of soap produced. The soap boiling pans were fitted with lids which were locked each night by the excise man. In 1833 the duty was reduced to an average of 1½ pence per pound but the tax was not totally removed until 1853.