Sir John Gay Newton Alleyne, 3rd Baronet (8 September 1820 – 20 February 1912) was a British businessman and engineer.
[2] It was he who designed the roof of St Pancras station which has a span of 240 feet (73 m) and forged the girders at Butterley.
Alleyne patented a method in 1861 which allowed hot ingots to be moved around a roller after it had passed by just one person.
However his most notable invention was probably the two high reversing steel mill patented in 1870, which used two steam engines to allow metal ingots to be repeatedly rolled in order to get the correct size and section.
[4] Alleyne married Augusta Isabella, daughter of Sir Henry FitzHerbert, 3rd Baronet, in 1851.