Characters from the cover of Daring Mystery Comics #3 (Marvel, 1940 Series).
Interesting facts are illustrated, such as: some steel used in England's new battleships was scrapped from German ships sunk in WW1; none of the planes currently used in WW2 will be in existence after 20 days of war; the mystery of a new explosive made from wood and air; a pilot thrown from his plane actually fell back into it; and several others.
Laughing Mask name changed to Purple Mask.