The Times (U.K.) has a report today on the 100th anniversary of the teabag, noting that originally it was not intended for placement in a teacup:
"Struggling to cut costs, Thomas Sullivan, a New York coffee merchant who turned to tea, sent out samples in small silk sachets rather than as loose tea. His penny-pinching was misunderstood by his customers who failed to realise that they were supposed to cut open the sachet and empty its contents into a pot before brewing their tea.
The result was an instant success with American tea drinkers.
The silk bag was swiftly replaced with gauze and in 1930 William Hermanson, of the Boston-based Technical Papers Corporation, patented the heat-sealed paper fibre teabag..."