The mauve dye Perkin had chanced on was much more effective and cheap to produce than natural dyes. He wisely patented his product and set up a factory to manufacture it in bulk, and before long it had stormed the fashion world. Other companies and an unprecedented variety of colours followed, turning synthetic dyes into big business and earning Perkin a knighthood from the Queen.
Discover more Historic secrets of the word's best inventions
Patients enjoyed the snack so much that the pair kept trying to finesse the recipe, making the first corn flakes from toasted maize in 1898. John took some persuading to go into business, but eight years later the brothers launched what was then called the Battle Creek Toasted Corn Flake Company. Fast forward over a century, and Kellogg’s says it now sells corn flakes in more than 180 countries worldwide.
As well as corn flakes, check out more Accidental inventions that made a fortune
Further testing confirmed that Pfizer’s scientists had unwittingly found a highly effective remedy for erectile dysfunction. Men had previously only had injections and prosthetic implants to choose from, but the new drug could be easily taken as a pill. Initially known as UK-92480, it was renamed Viagra, and when it first went on sale in 1998 it became the fastest-selling drug of all time.