Long before our modern day communication systems, man found that trumpets made from shells produced a sound that carried for many miles. By using as series of trumpet blasts, messengers were able to communicate fairly detailed messages from village to village, tribe to tribe.  (Note:  The Seashell Trumpet Site is a great place to learn how to make your own shell trumpets and other instruments!!)
In some countries, shells have been strung or tied together, or they have had seeds of sand added to them and then been sealed off so that they act as a rattle.  This was then used to accompany song and dance.

Check in here to see how to make a conch horn, to see what they look like and how they sound.

Some ways in which shells were or still are used are:

• as a summons to religious ceremonies as well as often playing a role in the ceremony itself.
• as a daily call to prayers. Shinto priests in Japan still use the Triton Trumpet shell for this even today!
• as a summons to call warriors to battle and to ring out triumphs in battle.
• as an announcement to herald the entrance of kings, emperors, heroes, or important persons. (or, in Fiji to this very day, to announce that fish is being sold at the market, or at the pier!)
• as a prelude, or to call people to public gatherings, such as tribal or community meetings, feasts, sporting events, etc.
• as a curfew announcement  - and is still used in Samoa today, as a signal to proclaim the return of a sailing vessel from a voyage or fishing trip.
• as a fog horn in the Mediterranean.
• as an accompaniment in songs, chants and dance throughout the Indo Pacific.
• as a ritual - blowing of the Triton Trumpet at sundown is still customary in Hawaii today.

Almost any shell modified by drilling a hole into it can be used to make music. Any large shell, unmodified and filled with water, can be used to make musical gurgling sounds (try it!!).  Most of us, at some time or other, have held an empty shell up to our ear to hear the music of the ocean waves (Note: The "whooshing" sound you hear is actually a mixture of all the sounds around you, bouncing off the hard sides of the shell: if you could find a completely quiet place to hold a shell to your ear, you wouldn't hear a thing!).

 Some shells commonly used for making music, and for signaling devices are:

Horned helmet  - This is a huge, heavy shell, which takes great lungs to blow, but also makes a BIG sound!!

Cassis cornuta

Charonia tritonis

Triton's Trumpet - (Note: The Triton Trumpet shell, as its name suggests, makes a Fabulous trumpet, since it grows to over 450mm (20 "), and has a very large aperture (i.e., opening) - so it can produce a very low, very loud sound which if blown by someone with strong lungs, can be heard for miles!!)

Queen conch -  (Note: This is the common large shell found lining garden plots, paths, and as door-stops (which is why it is sometimes refereed to as the "door-stop conch"!) Throughout North America.  In many parts of Florida, however, pollution and over-collecting for commercial purposes have nearly eliminated many local populations, so the species is now protected in the USA, although some are still imported from the West Indies.)

Strombus gigas

Cassis tuberosa

King Helmet  - Lives in the Caribbean Sea, and gets up to a foot (300mm) long, and very heavy.

Giant Frog shell - Indian and Pacific Ocean.  I don't know why they are called Frog Shells.

Bursa bubo

Strombus galeatus

Giant Stromb or conch - From Central America.