Rose DeWitt Bukater: Now it's brandy in the smoking room. They'll retreat to a cloud of smoke and congratulate each other on being masters of the universe.
Jack: I figure life's a gift and I don't intend on wasting it. You don't know what hand you're gonna get dealt next. You learn to take life as it comes at you. To make each day count.
Brock Lovett: Dive six, here we are again on the deck of Titanic. Two and a half miles down. Three-thousand, eight hundred and twenty-one meters. The pressure outside is three-and-a-half tons per square inch. These windows are nine inches thick, and if they go, it's sayonara in two micro-seconds.
Cal Hockley: You're a good liar.
Jack: Almost as good as you.
Rose Calvert: It's been 84 years and I can still smell the fresh paint. The china had never been used. The sheets had never been slept in. Titanic was called "The Ship of Dreams". And it was, it really was.
Officer Lightoller: Get back I say, or I'll shoot you all like dogs!
Chosen answer: During the several years it took to construct the ship probably, or in any of the supplies/food brought on board, or in the furniture brought on board. A single pregnant female rat can be responsible for thousands of rats in a very short space of time (the offspring are not too choosy about who they breed with).
Soylent Purple
A pregnant female rat could have made a home in a underneath a third class couch and had the other rats then all the females would have baby rats quickly.