Pen nib escape and evasion compass

British Bank No.433 nib by West Brooks & Co. Ltd. Leicester.  This appears to be a standard 'dip-pen' nib but close inspection reveals a tiny indentation punched in the centre at the balance point.  The nib is magnetized and by placing the indentation on a pivot would swing North.  Alternatively the nib could be carefully floated in still water to the same effect.  Excellent working condition and rare to find.  The final photograph shows the nib balanced on a mapping pin.  Stock code E22438.