In this letter of 10 April 1865 to John Hall, Canterbury’s secretary for public works, George Dobson records his conclusion that Arthur’s Pass is the best route across the Southern Alps.

Minchin’s Station April 10th 1865
West Coast Road

Sir,
I have the honor to inform you that after a careful examination of the country between the Waimakariri & Taramakau I have come to the conclusion that Arthur’s pass is the most practicable one in the range.
I enclose a list & description of the different passes explored by me during the last month.
I am now going, by appointment, to my father’s camp at Arthur’s pass, to inform him of the result of my exploration, and to render any assistance he may require from me, after which I shall return to Christchurch with as little delay as possible, and shall there be able to give you a more detailed account of my exploration, than I can do in writing from here
I send you this letter by Matthew Russell who has accompanied me during the whole of my journeys, and have directed him to call at your office in case you should have any letters to send to me.
I have the honor to be
Sir
Your obedient servant,
George Dobson.

The Hon John Hall
Secretary for Public Works
Christchurch