Thanks to Betty from Articulations! Go see her video on the ISO Standard Exit Sign here: https://youtu.be/i5uSlAw8U9s - and pull down this description for links to all her sources. The St Lawrence Burns were a series of deliberate fires in the soon-to-be-demolished village of Aultsville, Ontario, which was due to be flooded to make way for the St Lawrence Seaway. The results changed the way buildings are constructed around the world, and saved lives. SOURCES: Setting Fires for Science (1958):
