Good evening,
You are correct Anthony, it didn't have a needle as it's a floating dial. Susan's link brings up a good point, the one near the end which is practically identical to yours. The description says the small arrow points to true north and the N to Magnetic north. This gives it a positive variation ie; to the east of true north.
In england we have a negative variation, as at May 2013, 1 deg 38 mins west in London. So the compass was not for use in this part of the world, but probably the Pacific coast of the USA. Or that ocean at least, the variation in the US goes from roughly 13 deg west on the east coast to 13 deg east on the west coast.
I have searched online for a table of variations over the years but no luck.
John915