Hi there,
Welcome to RootsChat.
May I please mention that there’s quite a number of chaps named  McPHERSON in New South Wales in 1870.   For example, just in the West Sydney electorate (so, the Sydney suburbs of Ultimo, Pyrmont, The Rocks, and much of the Sydney CBD)  there’s the following chaps.
NSW electoral roll 1870 WEST SYDNEY
McPherson  Daniel, residence,  106 Victoria St
McPherson  Dougal, householder, Victoria place
McPherson  Duncan, householder, 60 Liverpool St
McPherson  Duncan, householder, 106 Victoria St
McPherson  Duncan, junior,  residence, 106 Victoria St 
McPherson  Evan, householder, Kensington St
McPherson  Hugh,  residence Piper’s lane Off Sussex St
McPherson James, freehold, 10 Waterloo place
McPherson  John, residence, 12 Kensington St
McPherson  Peter, residence, Liverpool St
McPherson  Richard, household, Liverpool St
McPherson  William, freehold 12 Kensington St
To be eligible to be enrolled (and it was not compulsory to enrol) you needed to be a) male,  b) British subject, either by birth or by naturalisation,  c) aged 21 years of age or more  d)qualified by residency and or property holding.  
Cheers,  JM