Silbo Gomero (Spanish for 'Gomeran Whistle'), also known as "El Silbo", is a whistled language spoken by inhabitants of La Gomera in the Canary Islands to communicate across the deep ravines and narrow valleys (gullies) that radiate through the island.....
Silbo Gomero (Spanish for 'Gomeran Whistle'), also known as "El Silbo", is a whistled language spoken by inhabitants of La Gomera in the Canary Islands to communicate across the deep ravines and narrow valleys (gullies) that radiate through the island.....
It is very interesting. see here..
http://en.wikipedia.org/wiki/Silbo_Gomero_language
http://www.youtube.com/watch?v=BRCgyrQgvsI
http://www.youtube.com/watch?v=MCID1pe6zhg