An interesting instrument, the exact purpose of which is not clear to me.  It may simply be a mining compass, to detect iron ore deposits, or it may be to demonstrate magnetic dip in different regions.  The spirit level could not be used at sea.  The needle keep doubles as a stand, and the instrument also has suspension loops.  Engraved The Paget No.540 H. Hughes and Son Ltd, Marine Opticians, London.

I can find no reference to this particular model.  Diameter of brass case 3.6 inches (91mm).

Loss of most original lacquer to the brass, the spirit level is a replacement, and there is a crack to the spirit level casing.  When held horizontally, the needle just about points north.  Original mahogany case, with green baize added over the original green baize.  Ganymede stock No. 35-3750.