plotting instrument meaning in Hindi

Examples

1. Two 1939 naval plotting instruments in mint condition and still bearing notes scribbled in German cost him dlrs 550.
2. "Mind you, I'm not one of these conspiracy nuts, " the 36-year-old bachelor explained the other day, sitting on a living-room rug cluttered with so many nautical charts and plotting instruments it resembled a ship's navigation room.
3. The "'Post Plotting Instrument "', or simply "'Post Instrument "', was the standard optical sighting system used by the UK's Royal Observer Corps ( ROC ) to determine the location of aircraft . It was used during the period from the mid-1930s into the early 1950s, and was one of the main sources of daytime tracking information during World War II.