Barometers are used to measure atmospheric pressure, but they were created in the 17th century when an Italian mathematician named Evangelista Torricelli, a former student of Galileo’s, devised the first artificial vacuum out of a glass tube filled with mercury. Subsequently, French philosophers René Descartes and Blaise Pascal used the instrument to determine altitude, but it was only by chance that scientists noticed that weather also affected the device’s measurements.

Mercury barometers have changed little since the days of Torricelli. Cistern barometers still consist of a slender glass tube sealed at the top and connected to a larger chamber at the bottom. Like the tube, the cistern is filled with mercury. When atmospheric pressure is reduced due to, say, the presence of moisture in the air, the mercury in the barometer falls. When it increases because of heat, the barometer rises. That’s why many barometers are marked with the word “Rain” next to low readings and “Fair” next to higher ones.

The other type of mercury barometer is a siphon barometer, whose glass tube is U-shaped rather than straight, obviating the need for a cistern. In either case, glass barometers are fragile, so they are usually mounted to a piece of mahogany or other decorative hardwood. And because the movement of the mercury in the tube can be very small, the English naturalist and microscope enthusiast Robert Hooke invented a dial that made the liquid’s subtle movements easier to perceive.

Early barometer manufacturers include Edward Naire, who pioneered ship barometers in the late 18th century. Like compasses of that era, Naire’s barometers had gimbal mounts and were housed in a ship’s binnacle. Scarlett and Champney’s, Negretti and Zambra, and James Green were respected English instrument makers of the early 19th century. A parallel development was the aneroid barometer, which did not rely on liquid to make its measurements. Lucien Vidie achieved that trick, although he had to fight off a patent infringer named E. Bourdon, who made 10,000 “manometers” before being forced to pay Vidie damages. By 1861, Negretti and Zambra were making pocket-size aneroid barometers, but these Victorian devices are less desirable to collectors than the more traditional stick or wheel barometers made by firms such as Berringer, Dollond, Rofsi, or Beerfield.


Best of the Web (“Hall of Fame”)

Alloy Artifacts

Alloy Artifacts

A tool collectors’ dream, this site is a deep repository of photos and info on 20th century hand tools and the co… [read review or visit site]

Drainspotting

Drainspotting

Josh and Cam Larios have created this site enabling people to upload and 'tag' photos of historic or artistic manho… [read review or visit site]

A Millers Falls Home Page

A Millers Falls Home Page

Randy Roeder has carved out a niche for himself with his fine website devoted to the history of the Millers Falls C… [read review or visit site]



Other Great Reference Sites

Most watched eBay auctions    

~*~estate Find~*~ Large Antique Barometer London England 1978 Chelsea Ships Bell Clock & Barometer 4 InchVintage Schatz Brass Ships Marine Barometer / Thermometer Untested GermanyChelsea Antique Ship's Wheel 8 Day Bell Clock And Barometer Ca. 1936Navy Naval Maritime Marine Ships Brass Boston Clock & BarometerAngelus Clock - Weather Station - Barometer - Calendar - Working ***very Rare***Short & Mason Tycos Pocket Barometer Circa 1880-90Antique Wooden Hanging Thermometer Barometer W Stenciling Unknown MakerRare Vintage 6" Abbeon Relative Humidity Indicator Ab1 Barometer West Germany NrMatching Pair Of Clock/barometer/thermometer Minatures For RestorationAntique English Made Barometer & Thermometer Wood With InlaysVintage 6" Brass Abbeon Cal Inc. Hygrometer Barometer Thermometer Germany Gauge Chelsea Clock & Barometer 1990sOlder Ornate Quimper French Faience Barometer Antique Flor De Lis Vintage Je Caldwell And Company Brass Mantel Shelf Table Clock And BarometerVintage Thommen 15000 Altimeter/barometer 16 Jewel - Swiss Made W/ Leather CaseCasio Pathfinder Prw3500t 7 Protrek Titanium Compass Alarm Barometer Thermometer1920-1930's Chelsea Ships Clock & Barometer In Original Swivel StandSeth Thomas Seasprite Ii Weather Barometer Model 1635 Nautical 2 Sunbeam Brass Colored Porthole Quartz Clock & Barometer 9" - Estate Listing NrSeth Thomas Corsair 5.25" Barometer 1504 By TaylorVintage Short And Mason Aneroid Barometer Wall Mounted Jaeger Lecoultre Barometer Model 7ab - Vintage - Made In FranceVintage Swift Instruments Boston Desk Top Barometer Mid Century ModernVintage Airguide Desktop Weather Station Thermometer Barometer UsaVintage Helm Ship Style Barometer Stormy, Rain, Change, Fair, Very, DryVintage Springfield Instrument* Weather Station Thermometer Barometer HumidityAntique Stanley London Pocket BarometerVintage Lucite Taylor Barometer Thermometer Hygrometer Desktop Weather StationVintage Antique Wheel Barometer Arch Top Thermometer And Glass Parts SparesLegacy Quest - Friends Of Nra - Weather Station - Clock Thermometer BarometerVintage Antique Original Wheel Barometer Brass Bezel & Convex Glass Parts SparesVintage Springfield Thermometer Barometer Humidity Wall Hanging Nautical Vintage 1976 Airguide Fishing BarometerDr. John- Anytime, Anyplace On Barometer 1974 Rarity Voodoo Blues Funk Nm MinusSmall Clock/barometer/thermometer For RestorationVintage Stellar Brand Ship's Wheel Barometer Made In Germany.Unique Antique Moose Antler Deer Antler Art German Barometer Captain Barometer Tk238 6" BrassOld Vintage Or Antique Wall Barometer Metal Dial Barometer PartsGerman Rebublic Miniature Furniture, Barometer And Grandfather Clocks,collectionVintage Georg Jensen Wall Mount Barometer By Henning Koppel Vintage Selsi Barometer Brass Wood Nautical Ships Wheel Made In GermanyVtg Compass Western Germany Barometer Nautical Maritime Ships Instrument