Windows of London buses and tramcars are being covered with adhesive netting as| an experiment to make the glass more resistant to shattering when bombs explode near by. If the netting stands up under wear and tear, it probably will be applied to all similar vehicles. Individual automobile owners likewise are taking precautions, some of them fastening mattresses to the tops of their cars to protect themselves against flying debris thrown by bombs and the shower of steel caused by bursting anti-aircraft shells.