The founder's navigational problem...
Joseph Masters and H.H. Jackson journeyed to Wairarapa in 1853 to select a site for a proposed settlement for working-class citizens from Wellington who could not otherwise afford adequate land. They purchased land from the Ngati Hamua and selected the site for the town that would later bear Masters’ name. Resting on the banks of the Waipoua he decided that it was the “gem spot of the valley”.
In 1854 William Mein Smith mapped Wairarapa and defined the boundaries of Masterton and Greytown during his trigonometrical survey. Arguably the best theoretician surveyor in the colony, he tackled new problems scientifically, being an early exponent of triangulation.
30 sections in the Masterton were allocated by ballot, and although another party immediately left for Greytown, there was a delay for those bound for Masterton, as a Mr John Hughes had not finished the survey of the town, most likley due to the dense bush that occupied the site.
On May 6, 1854 the first party of settlers set out from Wellington; It was a slow and difficult journey. They journeyed past W.H. Donald’s Manaia Station and on to the site of Masterton. Despite previous visits to the site by both John Cole and Michael Dixon, the party was unsure of where the boundaries of the proposed township were. It was crucial that they found the correct site, as WH Donald had threatened Dixon that if his stock strayed off the surveyed portion, he would “drive them away to the devil”.
After some hunting around the party did manage to find the surveyed lands and went on to establish the town.
(Sources: Dictionary of New Zealand Biography & Wairarapa Time Age)
How the founders could have found Masterton...
The cache is not located at the published coordinates, but lies in a spot where the founders may well have camped their first night. To find it, you will need to use a triangulation technique that William Mein Smith would have been very familiar with, and find some prominent hilltop landmarks that the founders would have seen on their journey.
These days the landmarks are marked by trig stations and their exact locations can be found on the LINZ Geodetic database
They are:
Rimutaka - (Trig 1221)
Girdlestone - (Trig 1226)
Rangitumau No.2 - (Trig 1527)
At the point where the cache is, these landmarks appear to be separated by horizontal angles as follows (going clockwise):
Rimutaka to Girdlestone: 69.576 degrees
Girdlestone to Rangitumau: 79.637 degrees
The cache location can be resolved - roughly - using a device called a "Station Pointer" and a map. To resolve the exact location you will need to use some trig calculations, and some research on the internet might help (visit link)
Note: The angles given for a grid projection such as NZMG and apply for a trigonomertical solution such as in the link above. Using programmes that generate projections against True north will likely result in some error.
There are two other caches that use the same navigational problem you may also wish to have a look at (thanks M@) GCKM2K and GCKM2M
Update December 2020: The cache has had to be relocated from its previous location as local "gardening" work has obliterated the hide. It is now at an offset from the puzzle solution coordinates, as there is now no place to hide a cache there. Details and hint are now in geochecker. Note that if you have previously used geochecker to get the cache location, you will need to run it again to get the new location.
You can check your answers for this puzzle here:
Good luck... you are looking for a 200ml Sistema container