Calculateur de Parallaxe / Parallax Berekenaar (Parallax Calculator) PB4Y Privateer plus the spares

plus the spares

25 inches diameter and ~ 2

The pressure tubes have been bent sideways for an unknown reason

(c) aural reception of modulated or unmodulated radio frequency energy using a loop antenna (d) aural-null directional indications of the arrival of modulated or unmodulated radio frequency energy using a loop antenna

and the right dial is labeled with the Japanese character for "Thousands"

Calculateur de Parallaxe / Parallax Berekenaar (Parallax Calculator) PB4Y Privateer plus the sparesWe 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