“On this day in 1849, a tailor named Jean Baptiste Jolly upturned a lamp containing turpentine onto his tablecloth and, taking notice of the cleaning effect it had, discovered dry cleaning–or so the story goes. This accidental discovery may or may not be true, but by the mid-19th century, a crop of early practitioners were offering dry cleaning services using a range of solvents.
A more colourful origin myth of dry cleaning includes a French sailor falling into a vat of turpentine wearing a dirty uniform. The sailor emerged from the vat and once his uniform had dried, found it to be surprisingly clean. The fate of this poor clumsy sailor, however, is never mentioned. Regardless of the origin, turpentine is no longer the solvent of choice for contemporary dry cleaners–or, fortunately, is it common practice for customers to become physically involved.
Today, the majority of clothes brought to dry cleaners are cleaned using a synthetic solvent called perchlorethylene–known by those in the industry simply as perc. The process used by contemporary dry cleaners is generic and consists of a pre-treatment, followed by a run in a machine involving perc or another solvent, and finished off with a post-spot in which remaining stains are removed.
Many dry cleaners maintain machines on the premises, however the potential carcinogenic effects of perc ensure that dry cleaners take extra precautionary measures. The state of California has determined perc to be a toxic chemical and starting in 2023 machines using the solvent will be banned.
The banning of perc perhaps opens the door for an ancient method used by the Romans to clean their togas. Liquid ammonia, produced from urine, was commonly used to treat and clean wool–of which the togas were made–before the discovery of soap. On second thought, perhaps it’s best to be forward-thinking in these situations.
The next time you knock something over, take a close look at what happens, the consequences could be more than meets the eye–but likely not.”