Finally, it was applied to a soldier's first experience of being under fire in battle.
This last sense gave rise to the modern usage An Americanism first found in print in a book by Davy Crockett, the folk hero and Congressman, in 1833.
The term backblock is found in 1850, referring to those territories of Australia split up by the government into blocks for settlement.
The more isolated and sparsely populated areas of the Australian interior are also known as the bush.
This is not a reference to the male anatomy, as some would believe, but an expression from the world of aviation.
On an aeroplane, the handles controlling the throttle and fuel mixture are often topped with ball-shaped grips, referred to by pilots as (naturally) balls.
This explanation overlooks the problem that few people were ever likely to buy that sort of quantity.