Keywords: Pipe bomb - black powder.jpg comment Photograph of a Black Powder Explosive source FBI http //www fbi gov/hq/lab/fsc/backissu/oct2004/research/2004_10_research03 htm other versions <gallery> Image pipe_bomb_-_black_powder jpg Photograph of a Black Powder Explosive Image pipe_bomb_-_smokeless_powder jpg Photograph of a Smokeless Powder Explosive Image pipe_bomb_-_binary jpg Photograph of a Binary Explosive Image pipe_bomb_-_c4 jpg Photograph of a C4 Explosive </gallery> PD-USGov Pipe bombs |