Calculateur de Parallaxe / Parallax Berekenaar (Parallax Calculator) PB4Y Privateer The watch will not wind

The watch will not wind and requires service by a qualified watchmaker

plus the spares

If it were a Nose angle indicator

Measures ~ 4 inches diameter and 3

Calculateur de Parallaxe / Parallax Berekenaar (Parallax Calculator) PB4Y Privateer The watch will not windWe frankly have no idea exactly in which specific application this Parallax Calculator was used (aeronautical or astronomical or ?). This large device measures ~13 inches square and has 3 clear disks and 1 clear arm that rotate around a center axis affixed to a metal rimmed wooden base board with what appears to be measurements of deflection. The disks may be secured by turning the 4 metal knobs. It is labeled in French and Dutch. A cool piece