An American Writer Just Back from Northern Ontario, Says Some of Our Old Prospectors Carry a Bottle of Prussic Acid As a “Means of Escape” When Lost in the Wilds

Prussic acid is also known as hydrogen cyanide. The comic is making fun of this American who implies that being in Northern Canada is so deadly that use would be better off poisoning yourself than dying in the cold if you were lost. Of course, no one would carry it for this purpose, and whoever told him was pulling his leg.