The introduction of the turbine engine at the beginning of the 20th century gave further subdivision of machinery and increase of economy, whereby greater speed became possible and comfort was increased by the reduction of vibration. At the same time the introduction of submarine bell signaling tended to diminish the risk of stranding and collision, whilst wireless telegraphy not only destroyed the isolation of the sea but tended to safety, as was seen by the way in which assistance was called out of the fog when the White Star Line liner "Republic" was sinking as the result of a collision off Martha's Vineyard (1909).