Bert Bolle Barometer - AbsoluteAstronomy.com

The Bert Bolle Barometer is a large water barometer. At over 12.5 metres tall, it is recognized as the largest barometer

Barometer

A barometer is a scientific instrument used in meteorology to measure atmospheric pressure. Pressure tendency can forecast short term changes in the weather...

in the world by The International Guinness Book of Records

Guinness World Records

Guinness World Records, known until 2000 as The Guinness Book of Records , is a reference book published annually, containing a collection of world records, both human achievements and the extremes of the natural world...

. The instrument was created in 1985 in the Netherlands, in 2007 it was reinstalled in the new Visitor Centre of Denmark, Western Australia

Denmark, Western Australia

Denmark is a town in the Great Southern region of Western Australia, south-south-east of the state capital of Perth. At the 2006 census, Denmark had a population of 2,732.-History:...

and was removed from there in 2011.

The Netherlands

The Dutch writer and barometer specialist Bert Bolle (*1947) designed and built the water barometer in 1985 as the focal point of the Barometer Museum, which he ran with his wife Ethne in the 18th century country house ‘Rustenhoven’ at Maartensdijk

Maartensdijk

Maartensdijk is a town in the Dutch province of Utrecht. It is a part of the municipality of De Bilt, and lies about 4 km north of Bilthoven....

in central Netherlands

Netherlands

The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

. In 1978 Bolle had written a book titled ‘Barometers’, which was translated into German and English. In 1983 he wrote a scientific sequel to his first book and developed some modifications of the mercury barometer system.

In 1985 Bolle and his wife set up a Barometer Museum in their country house. Their aim was to create a collection based on loans of barometers from private collectors and museums in the Netherlands. To obtain these loans, a massive publicity campaign was undertaken. Bolle wanted something to make the museums launch spectacular, an appliance that would be impressive and definitive which would serve as the centre point of the Barometer Museum. He decided to design and make a water barometer, paying homage to the 17th century scientists, such as Evangelista Torricelli

Evangelista Torricelli

Evangelista Torricelli was an Italian physicist and mathematician, best known for his invention of the barometer.-Biography:Evangelista Torricelli was born in Faenza, part of the Papal States...

and Gasparo Berti

Gasparo Berti

Gasparo Berti was an Italian mathematician, astronomer and physicist. He was probably born in Mantua and spent most of his life in Rome. He is most famous today for his experiment in which he unknowingly created the first working barometer...

who produced some of the first and most crucial vacuum

Vacuum

In everyday usage, vacuum is a volume of space that is essentially empty of matter, such that its gaseous pressure is much less than atmospheric pressure. The word comes from the Latin term for "empty". A perfect vacuum would be one with no particles in it at all, which is impossible to achieve in...

experiments, and created the first water barometers alongside their houses between 1640 and 1660. Bolle's old three story country house had ample height, the highest point of which was the roof of the main hall: a leaded glass

Leaded glass

Leaded glass may refer to:*Lead glass, potassium silicate glass which has been impregnated with a small amount of lead oxide in its fabrication...

cupola

Cupola

In architecture, a cupola is a small, most-often dome-like, structure on top of a building. Often used to provide a lookout or to admit light and air, it usually crowns a larger roof or dome....

. The apex of the hall was over 12 metres from the hall floor; a perfect environment for such an enormous instrument.

Bolle decided to make a construction of four borosilicate glass

Borosilicate glass

Borosilicate glass is a type of glass with the main glass-forming constituents silica and boron oxide. Borosilicate glasses are known for having very low coefficients of thermal expansion , making them resistant to thermal shock, more so than any other common glass...

(e.g. Pyrex

Pyrex

Pyrex is a brand name for glassware, introduced by Corning Incorporated in 1915.Originally, Pyrex was made from borosilicate glass. In the 1940s the composition was changed for some products to tempered soda-lime glass, which is the most common form of glass used in glass bakeware in the US and has...

) pipes of 90 mm diameter. He fitted the pipes to a nine metre long solid oak plank, which was one metre wide at the base. For the top three metres of the barometer, a 25 mm thick polymethylmethacrylate (e.g. Perspex) sheet was used. The reservoir chamber was also made of borosilicate glass

Borosilicate glass

; with a diameter of 600 mm the capacity of this reservoir was enough to hold 150 litres of water, which was necessary to make the barometer work properly. The first successful test runs took place in November and December 1985.

Bolle designed the top end of the water barometer to be connected to a rotary vane pump

Rotary vane pump

A rotary vane pump is a positive-displacement pump that consists of vanes mounted to a rotor that rotates inside of a cavity. In some cases these vanes can be variable length and/or tensioned to maintain contact with the walls as the pump rotates. It was invented by Charles C...

, which was governed by timer relay

Relay

A relay is an electrically operated switch. Many relays use an electromagnet to operate a switching mechanism mechanically, but other operating principles are also used. Relays are used where it is necessary to control a circuit by a low-power signal , or where several circuits must be controlled...

s. At ten minute intervals, the pump evacuated the air from the glass pipe, causing the 12 metre tall instrument to fill with 55 litres of water within one minute. Visitors were invited to climb the stairs and follow the water to the top, where it started to boil spontaneously (see below). The huge register plate had two scales: centimeters of water and millibar. . Water vapour pressure depresses the reading of water barometers and the magnitude of this error increases with temperature. Thus, a rule of thumb was provided to make a correction for temperature. After a reading period of five minutes, air was admitted to the top area of the pipe. Within a couple of minutes all the water would return to the cistern downstairs, after which the ten minute pump cycle would start again. Visitors were able to watch a real living instrument the whole day.

The instrument proved to be a massive drawcard and appeared several times in the media during the subsequent twelve-year period during which Bolle's Barometer Museum operated. In 1998 the museum was closed down.

Australia

Bolle and his wife migrated to Australia in 1999, but the maker didn’t want to part with his creation, so the barometer was brought with them to Australia, where Bolle donated it to the community of Denmark, a small town in Western Australia. The town didn’t have a building high enough to house the enormous instrument, but in 2004 plans were adopted for a new multi-function Visitors Centre, the centre part of which would be The Barometer Tower, built especially for the instrument.

The Shire of Denmark made the water barometer a local monument, named The Bert Bolle Barometer. Furthermore the shire announced that the tower would be dedicated to the water barometer and the history of weather instruments in general and access would be free of charge. In 2007 the Denmark Visitor Centre was finished. It was officially opened on 10 August by the Minister for Tourism in Western Australia Mrs Sheila McHale

Sheila McHale

Sheila Margaret McHale is a former Australian Labor Party MP in the Government of Western Australia. Prior to retirement, she served as Member for Kenwick and Minister for Disability Services, Tourism, Culture and the Arts, and Consumer Protection....

.

In the Barometer Tower the Bert Bolle Barometer stood on a stainless steel pedestal. The vacuum pump cycle became shorter than it was in the Netherlands; reduced to six minutes from the previous ten. The timer relays had been replaced by a PLC

Programmable logic controller

A programmable logic controller or programmable controller is a digital computer used for automation of electromechanical processes, such as control of machinery on factory assembly lines, amusement rides, or light fixtures. PLCs are used in many industries and machines...

, which now governs a refined and modernized vacuum system with 11 solenoid valve

Solenoid valve

A solenoid valve is an electromechanical valve for use with liquid or gas. The valve is controlled by an electric current through a solenoid: in the case of a two-port valve the flow is switched on or off; in the case of a three-port valve, the outflow is switched between the two outlet ports...

s. Operating eight hours per day, seven days a week, the water barometer was constantly ‘on the move’.

Visitors could walk up the stairs and take a reading in the Reading Room atop the Tower.
At the moment when the water reachedd its highest possible point in the glass pipe, visitors could witness an interesting physical phenomenon for about a minute. The air pressure above the water had lowered dramatically. Therefore the evaporation of the water happened so vigorously that the water started to boil spontaneously, although its temperature rarely exceeded 20 degrees. This ‘cold boiling’ is contributed to by air bubbles that were formed in the water column.
As soon as the pump was disconnected, the evacuating of the pipe stopped and the water level became calm again, enabling people to take a reading. During the time the water level was calm, there was still some turbulence at the surface due to air bubbles rising to the top of the apparatus.
Although water vapour pressure depressed the barometers pressure reading, visitors were told how to correct for this error and thus calculate the real air pressure, and could then compare it with the accurate Vaisala

Vaisala

Vaisala is a Finnish company that develops, manufactures and markets products and services for environmental and industrial measurement.The major customer groups and markets are national meteorological and hydrological services, aviation authorities, defense forces, road authorities, the weather...

digital standard barometer in the Tower.
After a reading period of two minutes, air was gradually admitted to the vacuum in the top area of the pipe. Within another two minutes all the water had returned to the reservoir downstairs, after which the six minute pump cycle of the Bert Bolle Barometer repeated.

Climbing the stairs in the Tower, a selection of antique barometers from Europe was displayed, along with five murals depicting the oldest barometer experiments dating from the 17th century.
In the Reading Room, tribute was paid to the pioneers of the barometer, the Italian scientists Galileo Galilei

Galileo Galilei

Galileo Galilei , was an Italian physicist, mathematician, astronomer, and philosopher who played a major role in the Scientific Revolution. His achievements include improvements to the telescope and consequent astronomical observations and support for Copernicanism...

and Evangelista Torricelli

Evangelista Torricelli

Evangelista Torricelli was an Italian physicist and mathematician, best known for his invention of the barometer.-Biography:Evangelista Torricelli was born in Faenza, part of the Papal States...

.
On the ground floor, Bolle had created several interesting physical experiments such as the Atmosphere Simulator, in which artificial highs and lows were created. There was also a Bell Jar

Bell jar

A bell jar is a piece of laboratory equipment used for creating vacuums.http://www.belljar.net/about.htm It can be similar in shape to a bell, and can be manufactured out of a variety of materials . A bell jar is placed on a base which is vented to a hose fitting, which can be connected via a hose...

showing interesting vacuum experiments with sound and air.

Record

Australia is known as a country of bizarre records for the sake of tourism, like the Big Banana

Australia's Big Things

The Big Things of Australia are a loosely related set of large structures or sculptures. There are estimated to be over 150 such objects around the country, the first being the Big Scotsman in Medindie, Adelaide, which was built in 1963....

or the Giant Ram

Australia's Big Things

. The size of the water barometer in Denmark was, however, a result of necessity, rather than a tourist gimmick. In order to function properly, a water barometer has to be quite large, with greater height producing greater accuracy. The Bert Bolle Barometer is thus a very accurate and genuine working instrument, as well as an impressive monument.

Recognition

In April 2008 the Bert Bolle Barometer was listed among the Top Hundred Australian ‘must see’ topics. Australian Traveller magazine revealed a list of 100 Things You Can Only Do In Australia. During its first year of its existence, the Denmark Visitor Centre recorded its 100,000th visitor.

25th Anniversary

In December 2010 the 25th anniversary of the barometer was celebrated. Bolle had written a booklet titled Weird and Wonderful Weather Predictors, of which 1,000 copies were printed and given to visitors in December as a present.

Denmark WA lost its Barometer

Shortly after the celebration of the 25th anniversary of the Bert Bolle Barometer the Denmark Visitor Centre lost its world attraction. Differences of opinion with the Board of Denmark Tourism Incorporated and the management of the Denmark Visitor Centre about promoting and signposting the water barometer and the Barometer Tower at the Denmark Visitor Centre lay at the bottom of an ongoing conflict. Eventually Bolle and his wife asked Denmark Council for the barometer to be given back to them, which was unanimously approved on 21 December 2010. The Barometer Tower was dismantled mid February 2011.

New location

Negotiations with a possible future owner of the barometer are in an advanced phase, albeit the location will not be in Denmark anymore. The plan is to house the water barometer in a 6x6 m brick tower with a small meteorological museum attached.

Copy

The Otto von Guericke Museum in Magdeburg

Magdeburg

Magdeburg , is the largest city and the capital city of the Bundesland of Saxony-Anhalt, Germany. Magdeburg is situated on the Elbe River and was one of the most important medieval cities of Europe....

in Germany erected a copy of the water barometer in 1995, after Bolle had been asked for his expertise. The barometer was situated in the centre of a spiral staircase. No attempt was made to outdo Bolle’s record. A narrower pipe was used, made of polycarbonate and the instrument was named the ‘Bert Bolle Wasserbarometer’ after the Dutch record holder.

Labour-intensive

Maintenance is an ongoing concern for the barometer, with one of the major issues being water vapour, which constantly enters the pump and could easily emulsify with the pump oil. Special provisions are made to prevent this. Since water vapour is extracted continuously, the water level in the reservoir needs to be topped up every day. In addition, the abundance of sunshine in the barometer's environment, combined with the presence of algae

Algae

Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...

in the rainwater that is employed, leads to a risk of algae growing within the water pipe. To address this, the owners have employed chlorine

Chlorine

Chlorine is the chemical element with atomic number 17 and symbol Cl. It is the second lightest halogen, found in the periodic table in group 17. The element forms diatomic molecules under standard conditions, called dichlorine...

to kill the algae, but the evaporation of the chlorine had to be specifically catered for. Wear and tear also places considerable strain on the vacuum systems vulnerable pump, its 11 solenoid valves and its relays. Finally, the barometer needs to be exclusively filled with pure rainwater, as tap water contains many minerals which may be detrimental to the barometer.

Because the water barometer has always been treated with great care, the instrument still looks almost new despite its age. A well-considered choice of durable materials like oak

Oak

An oak is a tree or shrub in the genus Quercus , of which about 600 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus...

and borosilicate glass

Borosilicate glass

certainly play an important role in its continued longevity. Other attempts to copy the instrument have floundered due to the use of inferior material, a lack of constant supervision, pollution of the pipe system and other factors reducing durability.

External links

The Bert Bolle Barometer in Europe and Australia (English) (German) (Dutch)
The 18th century country house ‘Rustenhoven’, formerly the Barometer Museum (English) (Dutch)

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