While soap dates back to ancient times, the earliest paintings of children playing with bubbles date to the 17th century, about a century after Europeans began to manufacture higher quality varieties of soap. In the 19th century, London’s A. & F. Pears used a John Everett Millais painting featuring a child playing with bubbles to advertise their soaps, suggesting that this practice was already well-established. Eventually, modern, purpose-made bubbles began to be manufactured for children to play with. Today’s bubbles are non-toxic and come in a variety of sizes, including a miniature option that’s commonly used for party favors. There are also many novelty bubble items on the market today, such as a patented formula that glows under ultraviolet light, machines that rapidly blow bubbles, and specially branded bubbles sold at souvenir shops all across the world. Retailers sell around 200 million bottles of bubbles each year and there are also many DIY recipes that kids and parents can make together at home, attesting to the long-standing, centuries-long appeal of bubbles.