He was the younger brother of Thomas Cubitt, the leading master builder in London in the second quarter of the 19th century, and he designed many of the housing developments constructed by his sibling. He was also younger brother of William Cubitt, the former Lord Mayor of London.
He built many bridges in his career but most of them were built in South America, Australia and India. One example of his work is to be found in Peterborough, where his cast iron bridge, which today carries the East Coast Main Line railway over the River Nene, was built in 1847.
Apart from some minor repairs and strengthening in 1910 (the steel bands and cross braces around the fluted legs to help carry increased train weights) it remains just the way he built it. It is now a unique "listed structure" - the only cast iron bridge in the UK carrying a high-speed train line.
Clearly interested in railways, Lewis also designed London King's Cross railway station, which was built in 1851-2, and the associated Great Northern Hotel, in 1854. A Granary by Cubitt behind King's Cross Station is planned to be refurbished to be part of the University of the Arts in the re-development of the railway lands behind the terminal.