[3] In the 1851 census Lewis was given as living at Water End Farm with his wife Susana (Susan) and their four children, the oldest of which was five.
[11] Over the next year, he picked up contracts for the Nelson Provincial Government along with his private work, such as surveying Native Reserves in the Pelorus and Queen Charlotte sounds.
They dissolved the partnership a year later in November 1857, and Lewis continued his practice until he took up a position with the Nelson Provincial survey department.
The main focus for discovering an overland route through the mountainous region that separated Nelson and the West Coast was via the Buller and its tributary the Maruia to the Grey.
[15] While at the Grey, a run-holder named James Mackay had been instructed by Chief Tarapuhi Te Kaukihi that the Maruia Plain was a central point which communicated with the north, east and west coasts.
[17] While Mackay was exploring the route through the Buller Valley, a local judge named William Thomas Locke Travers tested a theory of his own.
Retracing their steps back up what they now realised was Cannibal's Gorge, they discovered a pass from the Upper Maruia to a new river, which was later named the Lewis.