Inventors began experimenting with automatic sprinklers around 1860. These systems started out as pipes with holes drilled in them. When a fire occurred, the water was turned on to control the fire.
当前正在显示可能无法访问的结果。
隐藏无法访问的结果当前正在显示可能无法访问的结果。
隐藏无法访问的结果