Timeline

Each dated object sits at its year, in the row for the question it answered. Tap one to open it.

91 dated objects on the axis. 20 have no single year in their records and are listed below.

Projection Polariscopelate nineteenth century · Parispolariscopelate 19th century · PhiladelphiaVibration MicroscopeParisSurveyor's CompassTroySurveyor's Vernier CompassTroyVernier Compass with TelescopeTroySurveyor's CompassWoodstockOctantmid 19th century · New York CityGeneral Radio type 726-A vacuum tube voltmeterTerrasphereWheastone BridgeBalanceNurembergSteelyard17th centuryPyrometerLondonSun Compass, BumsteadSlide Rule, Chemical, Sally RideVoltmeter / Ammeter, E-1BarographSundial compasslate 17th–early 18th centuryTraveling sundial and compassearly–mid-18th century