A black and white photo of the Titanic, taken from the side, sailing on the ocean.



A picture of the side of the Tianic while it is docked.

A popular theory among scientists is that the Titanic sank because the rivets used in the plating of the hull were too weak. The rivets on the Titanic were made of iron, and iron became cheaper as it became less pure. The standard iron of the time was called No.4, but the Titanic build orders use iron No.3. These work orders were signed by Bruce Ismay, who was the managing director and a chairman at White Star Line (the company who owned the Titanic). The No.3 iron was weaker because it had more of something called “slag” - impurities which are often not as strong as the iron. Scientists such as Jennifer Hooper McCarty believe the weaker rivets caused the hull plates to split apart when the ship grazed the iceberg.

When the Titanic’s hull was breached, the flooding began in a boiler room. Frederick Barrett was the leading fireman aboard the Titanic, and is a well-known survivor of the tragedy. At the time of the collision he was working in boiler room 6, the specific room where flooding began. When he testified in court, he described the event as a loud sound coming towards him before the flooding began. The flooding was fast because the Titanic had not been built for the type of collision it had. Because of this, once the emergency lights came on the gates could not be closed fast enough to block the water.Those on the bridge were unaware that there had been a breach, and did not open the gates for lower-class passengers and crew to evacuate. And so the ship began to flood, some trapped in the lower levels as people scrambled for the upper decks