Again, while filing material away I came across this piece that throws an interesting insight into the Northside/Southside division.
Isle of Man Government. Northern Railway: Report of Committee. n.p. [Douglas]: n.pub. [Isle of Man Government], 1877.
 “In addition to this the Railway will tend to consolidate the interests of the North and the South.
The line of mountain land which separates one side of the Island from the other, has a tendency to cause the interests of these portions to be looked upon as separate and distinct from each other, and prejudices occasionally show themselves, which more frequent communication will lessen or prevent.”