A show globe is a glass vessel filled with colored water and hung outside a pharmacy. Show globes were once the universal symbol for the practice of pharmacy in the English-speaking world, but they were phased out in the 1950s and replaced by the mortar and pestle symbol. Today, it is extremely rare to find a pharmacy which displays a show globe, although plentiful show globes are available in antique stores and at auction for people who like to collect these interesting pieces of medical history.
The first documented examples of show globes emerged around the 17th century, in England. Researchers have suggested that the show globe evolved when the professions of druggists, chemists, and apothecaries started to merge in the 1500s. Prior to this period, these professions competed fiercely for customers, and the training received was markedly different. As the professions began to merge, skill at compounding drugs began to be important, and show globes were used to demonstrate compounding ability, since creating the necessary chemical reactions to color the water in the globe could be tricky.
Show globes could hang or be freestanding, depending on personal taste. Most resembled oversized fancy perfume bottles, with rounded bases and elaborate necks, and some included etched glass and ornate metal frames. The color inside was chosen at the discretion of the individual pharmacist, and some pharmacists even created stripes and swirls in their show globes to showcase their skills.
Some people have suggested that the show globe was like a proof of abilities in the era before the practice of pharmacy was regulated. By displaying a show globe, a pharmacist could demonstrate skill at formulating drugs, boosting consumer confidence. However, pharmacists could easily use recipe books for their show globes, and skill at compounding drugs would not be useful without the accompanying medical knowledge, especially in an era when toxic materials like arsenic and mercury were used in medications.
Most likely, the show globe originated as a clear visual symbol which could be easily interpreted by illiterate customers. Graphic signs were used by many businesses and professions well through the 1800s so that customers understood which service was offered, and the tradition of visual representations for specific trades still endures. Barber shops, for example, are often decorated with barber poles, and many historic pubs and inns retain their graphic signs for cultural value, as for example in the case of numerous pubs called "The Crown" in England which can be identified by the wooden crowns hung over their doors.