Seven centuries of scientific instruments, searchable and connected.

One hundred and eleven instruments from the Smithsonian's open-access collections, from an English astrolabe made between about 1300 and 1450 to a Civil Defense radiation calculator from 1963. Start with a question, play the mystery object game, work a slide rule or an astrolabe yourself, or follow a trail. Every object links to the museum's own record.

Start with a question

Where am I?Compasses, sextants, and surveying instruments. 20 instrumentsWhat time is it?Sundials and chronometers. 8 instrumentsWhere are the stars?Astrolabes and star finders. 17 instrumentsHow much?Slide rules, calculating machines, and balances. 31 instrumentsWhat can't the eye see?Microscopes and instruments for light. 22 instrumentsWhat is the weather doing?Barometers, thermometers, and hygrometers. 4 instrumentsHow do I draw it?Pantographs and drawing instruments. 4 instrumentsWhat is the electricity doing?Meters and electrical instruments. 5 instruments

English Planispheric Astrolabeabout 1300-1450 Persian Planispheric Astrolabe1372-1373 Italian Planispheric Astrolabeabout 1475 Planispheric Astrolabe Engraved with Arabic Script1504 Hartman's Planispheric Astrolabe1537 · Nuremberg European Planispheric Astrolabe1542 French Planispheric Astrolabe1548 Planispheric Astrolabe Similar in Style to Those of Egnazio Dantiabout 1580 Persian Planispheric Astrolabe1611 Indo-Persian Planispheric Astrolabe1643 · Lahore Indo-Persian Planispheric Astrolabe1659 · Lahore Persian Planispheric Astrolabeabout 1682 Planispheric Astrolabe from Muslim Spain1691 Persian Planispheric Astrolabeabout 1715 · Eşfahān Microscope1730-1760 Portable Equatorial1748 Sundialabout 1750 · New England Microscopeafter 1750 · Nuremberg Persian Planispheric Astrolabe1775 Spy Glass1775-1800 · London Celestial Planisphere Called Astrolabe for Latitude 411780 Beam Balance1780 - 1820 Surveyor's Vernier Compassabout 1785 · Philadelphia Pocket compass from the Lewis and Clark Expedition, 1804-1806about 1804 · Philadelphia Balance1807 box chronometer movementc1810 · London James Wilson's Terrestrial Globe, 18111811 · Vermont Bond Marine Chronometerabout 1812-1815 · Boston Thomas Arithmometerabout 1820 · Paris Microscope, Lerebours1829 · Paris Hair Hygrometerabout 1829 · Paris Polariscopearound 1830 · Paris Heliostatabout 1830 · Paris Daniell Hygrometerabout 1831-1844 · London Polariscopeca. 1834-1844 · Paris Solar Microscopeabout 1840 Melloni Benchearly 1840s · Département de Ville-de-Paris Solar Compass1840s · Cincinnati Grunow Spherometerafter 1849 · New York City Patent Model for Circular Slide Rule Invented by John W. Nystrombefore 1851 · Philadelphia Hatfield Machine for Adding Numbers1854 · Lewisburg Sextant1856-1866 · New York City Equatorial Sextant1856 Hill Arithmometer1857 · Waltham William W. Wythes Cyclo-Ellipto-Pantograph Patent Model1858 · Philadelphia Burns Addometer1858 · New York City Spectroscopeearly 1860s · Paris Patent Model for Triangular Drafting Scale Invented by Josiah Lyman1863 · Lenox Liquid Compass1863 · Boston Chronographabout 1868 · Boston Rotating Mathematical Table, Sinclair's Freight Computer1869 · Waterville Barbour Calculating Machine Model1872 · Boston Spectroscope1873-1881 · New York City Spectrometer1873-1881 · New York City Winlock & Huddleston Psychrometer1873 · Boston Baldwin Arithmometer1874 · Philadelphia Patent Model for Estimator Slide Rule Invented by Fredric Maurice Stapff1874 Barbour Calculating Machine1875 · Boston Baldwin Calculating Engine1875 · St. Louis Patent Model for Parallel Rule and T-Square by Eugene Towne1877 · North Dana Jamin Apparatus1879-1882 · Paris Projection Polariscopearound 1880 · Paris Leyden Jar Batteryabout 1880 Dry Card Compass with Binnacle1880 · Glasgow Log and Rotor, Patent Model1881 Patent Model for Simplex Slide Rule Clasp Invented by Rudolph C. Smith1887 Comptometerca. 1887 Microscopeabout 1890 · London Keuffel & Esser 1741 Thacher Cylindrical Slide Rule1890s · New York City Odhner Arithmometerabout 1896 · St. Petersburg Heliostataround 1900 · Pittsburgh Elliptic Trammelabout 1900 Peerless hanging letter scalec. 1900 Odometer by J. D. Robertsc. 1900 Fessenden electrolytic radio signal detector1903 Triner postal scale1912-1926 Ski-Optometer (Woolf Phoropter)1913-1917 Plotter, Driftca. 1918 Sextant, Brandis, with Willson Bubble Telescope, Earlyca. 1919 Recorder, Air Distanceca. 1922 Receiver, Radio Range, ARC, Lab Prototype, Model B1929 Sight, Drift & Ground Speed, Gattyca. 1931 Watches, Army Air Corps, Avigation [Air Navigation], A-6ca. 1934 Circular Slide Rule, William J. Powell1935 Dead Reckoning, E-6B, Prototype1942 Plotting Board, Navy, Mark 3A1942 Indicator, Carbon Monoxide1943 Libby Low Level Counter1950 · Cambridge Pickett N600-ES Log Log Duplex Slide Ruleabout 1962 · Chicago Civil Defense radiation dosage calculatorc. 1963 Civil Defense pocket dosimeterc. 1963 Projection Polariscopelate nineteenth century · Paris polariscopelate 19th century · Philadelphia Vibration MicroscopeParis Surveyor's CompassTroy Surveyor's Vernier CompassTroy Vernier Compass with TelescopeTroy Surveyor's CompassWoodstock Octantmid 19th century · New York City General Radio type 726-A vacuum tube voltmeter Terrasphere Wheastone Bridge BalanceNuremberg Steelyard17th century PyrometerLondon Sun Compass, Bumstead Slide Rule, Chemical, Sally Ride Voltmeter / Ammeter, E-1 Barograph Sundial compasslate 17th–early 18th century Traveling sundial and compassearly–mid-18th century

Trails through the collection