October – Niels Bohr presents his theoretical principle of complementarity at the Fifth Solvay Conference on Physics. October 4 – Carving of the sculptures at Mount Rushmore, South Dakota begins. October 6 – The Jazz Singer, starring Al Jolson, premieres at the Warner Theater in New York City. Although not the first sound film, and containing very little recorded speech, it is the first to become a box-office hit, popularizing "talkies" (although silent films continue to be made for some time). October 8 – The "Murderers' Row" team of the New York Yankees complete a four-game sweep of the Pittsburgh Pirates in the World Series baseball championship in the United States. October 9 – The Mexican government crushes a rebellion in Veracruz. October 18 – The first flight of Pan American Airways takes off from Key West, Florida, bound for Havana, Cuba. October 25 – The Italian ocean liner Principessa Mafalda capsizes off Porto Seguro, Brazil; at least 314 people are killed. October 27 Queen Wilhelmina of the Netherlands opens the Maas–Waal Canal in Nijmegen, the Netherlands. At 5:50 a.m. a ground fault gives way, causing the mine and part of the town of Worthington to collapse into a large chasm located in Ontario. Nobody is injured in the incident, as the area has been evacuated the night before after a mine foreman noticed abnormal rock shifts in the mine.
October – Niels Bohr presents his theoretical principle of complementarity at the Fifth Solvay ,Conference on Physics. October 4 – Carving of the sculptures at Mount Rushmore, South Dakota begins. October 6 – The Jazz Singer, starring Al Jolson, premieres at the Warner Theater in New York City. Although not the first sound film and containing very little recorded speech, it is the first to become a box-office hit, p,opularizing "talkies" (although silent films continue to be made for some time). October 8 – The "Murderers' Row" team of the New York Yankees complete a four-game sweep of the Pittsburgh Pirates in the World Series. baseball championship in the United States. October 9 – The Mexican government crushes a rebellion in Veracruz. October 18 – The first flight of Pan American Airways takes off from Key West, Florida, bound for Havana, Cuba. October 25 – The Italian ocean liner Principessa Mafalda capsizes off Porto Seguro, Brazil; at least 314 people are killed. October 27 Queen Wilhelmina of the Netherlands opens the Maas–Waal Canal in Nijmegen, the Netherlands. At 5:50 a.m a ground fault gives way causing the mine and part of the town of Worthington to collapse into a large chasm located in Ontario. Nobody is injured in the incident, as the area has been evacuated the night before after a mine foreman noticed abnormal rock shifts in the mine.