Wiktionary
show globe
n. A glass vessel containing coloured liquid, formerly (from the 17th century) displayed outside pharmacy.
Wikipedia
Show globe
A show globe is a glass vessel of various shapes and sizes containing a colorful liquid. It has been a symbol of pharmacy from the 17th century England to the early 20th century in the United States. It marked the drugstore or apothecary in much the same way as the barber's pole marked tonsorial establishments in some countries. People who were illiterate needed such symbols to locate these medical practitioners.
Show globes were displayed almost exclusively in English-speaking countries, contrasting with the wider use of the mortar and pestle as a pharmaceutical symbol.