Short answers, pulled from the story.
The first true rolling mill arrived in England in 1590. This machine, known as the slitting mill, came from Belgium and passed flat bars between rolls to create plates and grooved rolls to produce rods.
Henry Cort was granted a patent for the use of grooved rolls in 1783. He was from Funtley Iron Mills near Fareham in Hampshire, England, and his design allowed mills to produce 15 times more output per day than with a hammer.
John Birkenshaw established the first rail rolling mill at Bedlington Ironworks in Northumberland, England, in 1820. This facility produced fish-bellied wrought iron rails that were 15 to 18 feet long.
Cold rolling increases the strength of steel via strain hardening by up to 20%. This process occurs below the recrystallization temperature of the metal and takes place at room temperature.
The Consett Iron Company exhibited a plate that was 20 feet long, 3 feet wide, and 7/16 of an inch thick. The plate weighed 1,125 pounds and was displayed at the Great Exhibition in London in 1851.