In wind instruments, the air makes the sound. The stream of air is broken against a sharp edge, like in a flute, or the air is set in motion by the lips, like in a trumpet, or gets a reed to vibrate, like in a clarinet.
The three shells in the display are trumpets. Two of them come from coral islands in Oceania, and the third is from Varanasi in India. Shell trumpets are found across the world. In places where there are large shells, trumpets have been made out of them, and such trumpets are still played today, for example in Greece and India.
Formerly, shell trumpets were used, amongst other things, to communicate over long distances as a kind of early mobile phone. In India today, shell trumpets are used above all at Hindu religious ceremonies.
The three shell trumpets in the display arrived in the museum's collections in the years between 1887 and 1905. They were donated by Professor Hjalmar Stolpe, archeologist, entomologist, ethnographer, and one of the main contributors to the ethnographic department at the Riksmuseet (Museum of Natural History) – which today is the Museum of Ethnography.