Letter bomb
A letter bomb, also called parcel bomb, mail bomb, package bomb, note bomb, message bomb, gift bomb, present bomb, delivery bomb, surprise bomb, postal bomb, or post bomb, is an explosive device sent via the postal service, and designed with the intention to injure or kill the recipient when opened. They have been used in terrorist attacks such as those of the Unabomber. Some countries have agencies whose duties include the interdiction of letter bombs and the investigation of letter bombings. The letter bomb may have been in use for nearly as long as the common postal service  has been in existence, as far back as 1764 ("see Examples"). Description. Letter bombs are usually designed to explode immediately on opening, with the intention of seriously injuring or killing the recipient (who may or may not be the person to whom the bomb was addressed). A related threat is mail containing unidentified powders or chemicals, as in the 2001 anthrax attacks. Use by suffragettes. One of, if not the first, groups to consistently use letter bombs on a wide scale were the British suffragettes of the Women's Social and Political Union in the years before the First World  War. The group were the original inventors of a form of letter bomb designed to maim or kill politicians or opponents. In 1913, numerous letter bombs were sent to politicians such as the Chancellor David Lloyd George and Prime Minister H.H. Asquith, but they invariably all exploded in post offices, post boxes or in mailbags while in transit across the country. Suffragettes also once attempted to assassinate a judge they considered to be anti-women's suffrage, Sir Henry Curtis-Bennett, with a "deadly" letter-bomb made partly out of bullets, but the bomb was intercepted by London postal workers  before it could reach him. Patentability. Letter-bombs, along with anti-personnel mines, are typical examples of subject-matter excluded from patentability under the European Patent Convention, because the publication or exploitation of such inventions are contrary to the ""ordre public"" and/or morality ().