Martians are starting to use a new weapon, which is a thick black smoke tube that they carry. The tube he carried to fire a large cylinder over whatever hill, wood or other possible hiding place for guns might be in front of him. The tube did not explode but let out an enormous amount of thick black smoke and it was death to breathe that smoke. Black smoke is a deadly gas used by the Martians launched by the tripods.
The writer was worry about the chemical weapon that some countries could use in the war. This can lead to a big disaster to the environment and human. The writer want to warn us about the imminent danger of using mass destruction weapons. When we read about the effects of the black smoke, we think about the effects of the atomic bombs