10 inventions that owe their success to World War One
By Stephen Evans BBC News, Berlin
The tea bag was not invented to solve some wartime problem. By common consent, it was an American tea merchant who, in 1908, started sending tea in small bags to his customers. They, whether by accident or design, dropped the bags in water and the rest is history. So the industry says.

http://www.bbc.co.uk/news/magazine-26935867