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The oldest barometers
The first steps in 1985
Bert Bolle’s ‘shopping list’
How the water barometer operated
The Guinness Book of Records Certificate
The Barometer Museum in the Netherlands
Contact
The water barometer, standing in the hall of the Barometer Museum in the Netherlands, about 1990.
Bert and Ethne Bolle retired in 1999, left the Netherlands and migrated to Western Australia, where they found their beautiful spot in the pristine environment of Denmark. Bert is a writer and Ethne an artist painter.
Ethne and Bert Bolle in 2005
During the last 12 years before their migration, they ran the Barometer Museum in their 18th century country house Rustenhoven at Maartensdijk in the centre part of the Netherlands. The main attraction in their museum was a giant water barometer in the main hall. The 12 metres high instrument was awarded the largest barometer in the world by The International Guinness Book of Records.
Bert, who had designed and built the instrument himself, didn’t want to part with his creation, and so the barometer made the journey to Down Under. It has come back to life in the Barometer Tower of the new Denmark Visitor Centre.
The exact date of discovery of the barometer and the name of the inventor are both subjects for debate. The reason for this is that, in its original form, the barometer was not invented as a weather forecasting instrument. Initially it was developed as a scientific instrument just to prove the existence of a vacuum, and at a later stage for following changes in the weight of the air. In other words, it was not invented with a predetermined, single aim in mind in the way that radio and television were deliberately developed to receive electronic signals.
In the 17th century people began to question the long-accepted ideas that a vacuum or air free space was impossible. The all-powerful church had dictated that idea for centuries. Just why was this so - was it indeed so? As is often the case where important discoveries are made, a simple event from the daily goings on of the time gave the clue to a breakthrough. Round about 1635 an elaborate series of fountains was being installed in the palace gardens at Florence in Italy. Water had to be pumped up from a very deep well. A suction pump was installed, but to everybody’s consternation it was found that the water rose no further than about eighteen Florentine yards - about thirty-three feet or ten metres. Although they did not realize it at the time, a vacuum had been created and no matter how hard they pumped, the water stayed in the well. The famous scientist Galileo Galilei, who had already attracted a lot of adverse criticism because of his new-fangled ideas, was approached for advice.
Galileo’s way of thinking was too strongly influenced by the old teachings of Aristotle for him to hit upon an explanation involving a vacuum. The dogmatic teachings were so firmly ingrained into his way of thinking that it never occurred to him that the water in the pipe was simply ‘held’ there by the force of the air pressing down on the water outside the pipe. He did go so far as to state that air had mass, but he did not make further deductions. All the same he did let other researchers know of the problem, like Gaspar Berti in Rome, and in 1639 serious experiments were carried out using an appliance about 35 feet (11 metres) high filled with water to try to create a vacuum.
Galileo’s successor to the post of court scientist to the Duke of Tuscany was Evangelista Torricelli who having found the notes of his predecessor and teacher went on to conduct further experiments. It seems that his initial trials involved water and that his aim was not only to create a vacuum but to prove that air pressure was responsible for supporting the water column. Torricelli was the first to try to “construct an instrument which showed changes in the air, sometimes heavier and coarser, at other times lighter and finer”. In 1644 Torricelli discovered that he could carry out his experiments more conveniently with mercury rather than with water, although water was still used by other scientists for some decades. Blaise Pascal erected a water barometer in Rouen in France in 1646 and Otto von Guericke, the mayor of Magdeburg in Germany installed one alongside his house round about 1654. In England scientists like Robert Hooke and Robert Boyle experimented with similar instruments in the sixties of the 17th century.
After 1670 the complicated water barometer had given way to the mercury tube. There were a few water barometers made by scientists during the next centuries, but these instruments were rare. About 1880 there was a water barometer in London, but since then the instrument seemed to have become extinct, until in 1985 Bert Bolle decided to design and build one for the Barometer Museum he intended to found with his wife Ethne.
Left: Berti’s vacuum experiment from 1639 in Rome.
Middle: Blaise Pascal’s barometer from 1646 in Rouen, France.
Right: von Guericke’s water barometer from circa 1654 in Magdeburg.
In 1978 Bert Bolle had written a book titled ‘Barometers’, which was translated into German and English in 1980. Three years later he wrote a scientific sequel to his first book and invented some modifications in mercury barometer systems. In 1984 Bert’s wife Ethne talked about starting something like a barometer museum in their 18th century country house. Bert gave it some time to think about, and the next year he thought the time was ripe to give the idea a go. His 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 should be the best remedy. Knowing that the press would not be very impressed by just a castle in the air, Bert decided to launch something spectacular first, an appliance that would be impressive and definitive, as the centre point of the Barometer Museum to be. When writing his barometer books, he had become impressed and inspired by the 17th century pioneers with their huge instruments. He would love to create his own water barometer! The old country house had three stories, with ample height, and above the centre of the main hall was the highest spot of the building: a leaded glass cupola of which the top part was over 12 metres from the hall floor. A perfect environment for such an enormous instrument.
Although there was no literature available about how to make your own water barometer, Bert knew in detail what had been built in the former centuries. He also had the advantage of the 20th century technology, which e.g. enabled him to abandon the lead pipes that had been used in the old days. Schott Ruhrglas in Germany made beautiful strong glass pipes in any size, and could supply a huge glass cistern too. Instead of filling the barometer from the top, a modern rotary vane vacuum pump could be used. Timer relays would make the pump alternately let the water go down in the pipe, or rise and so forth. There was a calibrated digital barometer of extremely high accuracy on the market to check the readings from the water barometer register plate. Those modern blessings challenged Bert to go on with his idea.
After a long period of investigation, Bert could start designing the barometer. Initially he made sketches and drawings by hand, later he used his Apple Macintosh computer. It is amazing how sophisticated the graphical Mac-programs already were in 1985.
Sketches, ideas, drawings, plans.
Meanwhile the Barometer Museum Foundation was set up and a Committee of Recommendation was established, consisting of curators from the Netherlands and abroad, scientists in the barometer world, and last but not least former prime minister Piet de Jong of the Netherlands. It had become time to make a ‘shopping list’ for the water barometer.
Bert Bolle chose a 90 mm glass pipe, consisting of four sections. Those pipes would be fitted to a huge oak plank of 9 metres height. The top 3 metres would be made in Perspex. A glass cistern of 60 cm diameter would hold 150 litres of water, enough to make the barometer work. Finding the wood for such an enormous plank was the first problem. Fortunately Bert knew a wood dealer who had just supplied a Dutch ship builder with extremely long sheets of French oak. The wood dealer managed to buy two sheets back, and offered to make the plank according to the design. Schott Ruhrglas in Germany came with generous quotations for the pipes and the cistern. Finally Bert had his ‘shopping list’ ready:
One French oak plank being about 9 M long, 40 cm wide, 40 mm thick, and 1 M wide at the base.
One steel top cover for the plank mentioned above.
One Pyrex glass cistern manufactured by Schott, Germany, 60 cm diameter.
One Pyrex glass cover of 12 mm thick, in two parts, for the glass cistern.
One rubber seal for the cistern cover.
One analogue and one digital thermometer for the glass cistern.
One aluminium stand for the glass cistern.
One circular collar with oak finish in two halves to fit around the stand of the glass cistern.
Four Pyrex glass pipes being 9 cm in diameter, three of them being 3 M long, one of them 2.50 M long.
One Pyrex glass cap for the top pipe.
Four aluminium fitting sets with rings for the flanges of the glass pipes.
One steel bracket to hold the pipe system.
Various small stainless steel parts, e.g. bolts, nuts, washers and rings.
One transparent Perspex plate of 3 M long, about 40 cm wide and 25 mm thick.
Two Perspex brackets, 25 mm thick.
One 6 mm thick white Perspex register plate, same size as the Perspex plate above.
One rotary vane vacuum pump, manufactured by Leybold Heraeus, Germany.
One Secuvac safety valve, manufactured by Leybold Heraeus, Germany.
One water detecting safety device.
One computerized multi-channel timer.
One camera plus monitor.
One relay cabinet.
Various cables.
A lot of money was saved, as Bert did a lot himself, and there were some good friends with helping hands. In total over 600 hours were involved to get the barometer completely installed and working. Fortunately the companies who supplied the materials, tried to help the Barometer Museum Foundation with discounts, but nevertheless over 10,000 Dutch guilders needed to be spent. Nowadays, if the barometer should be totally rebuilt, all materials would cost between 15,000 and 20,000 Australian dollars, not counting the hours and the fact that the German glass factory will stop producing their special industrial Pyrex glass pipes and cisterns within a couple of years time.
From mid 1985 all materials were acquired and prepared for their final use. In November of the same year, the barometer was erected and made its first test run.
Working on a scaffold, 10 metres above the ground.
How the Water Barometer operated
A microprocessor regulated the vacuum pump, which was connected to the top end of the water barometer by a copper pipe. At ten minutes intervals, the vacuum pump was switched on, and evacuated the air from the 11.5 metre long glass pipe, causing the more than 12 metre tall instrument to fill with 55 litres of water within two minutes. Readings could then be taken at the second storey level of the museum. After five minutes, air was admitted in the pipe, such that water returned to the cistern in three minutes. A vacuum was then drawn again, etc. etc.
The pipe passed the balustrade on the first floor before it reached the leaded glass cupola.
Visitors who wanted to take a reading, needed to climb ten metres of stairs first. Finally they reached a platform in the attic, just above the leaded glass cupola. Near the platform, the wooden plank was continued by a Perspex plate. There was a board on which the Vacuum Pump Cycle was explained, and the water temperature in the cistern was shown on a display.
Where the oak plank met the Perspex plate.
The white Perspex register plate had two scales; centimetres above the water surface in the cistern and millibars or hectopascals. On the explanation board, a rule of thumb was given to make a correction for temperature. Water vapour pressure depresses the actual reading and this ‘error’ increases with temperature.
The platform above the leaded glass cupola.
Every ten minutes, visitors could witness an interesting physical phenomenon, when they made the climb to the cupola area. At the moment the water reached its highest possible point in the pipe, the air pressure above the water had been lowered so dramatically, that the water started to boil spontaneously, although its temperature was just about 20 degrees! This ‘cold boiling’ was reinforced a bit by air bubbles that were formed in the water column. As soon as the pump stopped evacuating the pipe, the water level became calm within a couple of seconds, thus enabling the visitors to take a proper reading.
The Guinness Book of Records Certificate
With the giant barometer installed, press releases could be sent out to the media to announce the museum plans and the request to obtain antique barometers on loan. Within just a few months, there were enough barometers offered on loan to arrange the displays and the walls. Meanwhile Bert Bolle claimed to have built the largest barometer in the world, and when the International Guinness Book of Records recognized the claim, it was big news again.
This certificate was proudly hanging two metres above the cistern.
In May 1987 the Barometer Museum opened its doors. Mrs Neelie Smit, Minister for Transport was invited as a representative of the Royal Dutch Meteorological Institute to open the Barometer Museum. She poured a symbolic last bucket of water in the cistern, together with Bert and Ethne Bolle’s daughter Puck. Nearly 200 guests witnessed the glorious ascending of the 55 litres of water.
Left: Minister Neelie Smit and Puck Bolle opening the Barometer Museum in May 1987.
Right: Former prime minister of the Netherlands Piet de Jong with Bert Bolle and minister Neelie Smit.
The opening was broadcast on Dutch national television in prime time on the News and in a tourist program. The museum, most especially the water barometer, would appear tens of times on national television in the next twelve years of its existence.
Left: Dutch National News, just before the official opening of the museum.
Middle: Japanese TV filming the representative of the International Guinness Book of Records, handing the certificate to Bert Bolle.
Right: American TV for an interview in the museum.
Since the Barometer Museum was only 10 Km from the Dutch national radio and television studios, it was a wanted spot for the makers of weather programs. All well-known weathermen of the Dutch TV were regular guests in the Barometer Museum. Bert was happy with all that publicity, as it would bring more visitors in. He never said no to the media and didn’t take much persuading if he was asked to participate in a lighthearted promotion, even if many hours of hard work would only yield a few minutes of TV. When the museum closed down, Bert and Ethne had over 90 square metres of newspaper and magazine articles in their archive!
Left: Weatherman Peter Timofeeff in the calibration room of the museum.
Middle: Bert pouring water over an actress in a running gag of a weather program.
Right: Very well known weather man Erwin Kroll explains on Dutch TV how the water barometer works.
There were hundreds of barometers, thermometers, hygrometers and weather houses to be seen. Most of the barometers were mercury instruments, mainly English, Dutch and French, dating from the 18th and 19th century. A modest entrance fee was asked, and there was a museum shop. Main attraction of course was the water barometer. Children used to trip the stairs up and down to follow the rising and falling water column. Some guests came especially to see the 18th century building. They had seen the old country house so often when they made an outing in that scenic part of the Netherlands, and now they had a chance to have a look inside.
Every single item in the museum had a description, and there were guides in several languages. There were many ‘extras’, e.g. an Apple Macintosh computer, connected to the Royal Dutch Meteorological Institute, showing the rain radar in the Netherlands, which was a unique item in the late eighties. The museum had purchased an extremely accurate digital barometer made by Vaisala in Finland. The barometer had two displays: one in the museum, the other one in the calibration room of the workshop where antique barometers were restored and new ones were made. The Bolle family employed over ten craftsmen to do all the specialist jobs.
Bert and Ethne regularly organized an exhibition on a theme, e.g. on Paulus Wast, a famous Dutch barometer maker. The most expensive mercury barometer ever sold in the world was made by Wast and was the centrepiece of the exhibition. A couple of years later, a weather house exhibition was held. The museum shop had 50 different models for sale, so there was a chance for every visitor to strike lucky. Bert had written a small book on weather houses. Over 2,000 people attended that exhibition.
The exhibition on antique weather houses in 1993 drew a lot of visitors.
When the big parking area was full, even the lawn was used.
In 1997 the Ministry for the Environment came with a new law to ban all mercury out of newly manufactured barometers. From 1999 onwards, it would be forbidden to make or even to sell new mercury barometers. That was a serious threat for Bert and his craftsmen who used almost 10% of the all the industrial mercury in the Netherlands. If the law would be adopted, the workshop and the museum were condemned to close. There was no compensation for the Bolle family and their glassblowers. Bert of course appealed to the law and fought like mad. He searched the publicity and approached most of the members of parliament, but the new law seemed to be inevitable. For Bert and Ethne, who already had serious intentions to migrate to another country, the bizarre plans of the Ministry for the Environment were the straw that broke the camel’s back. They went to a migration agent to enquire about living in Australia, and set the first steps to eventually lodge an application for a permanent visa.
In April 1998, when the chances to prevent the anti mercury law had become minimal, Bert and Ethne had a very important guest: Her Majesty Queen Beatrix of the Netherlands. She had an elaborate look around in the museum, and finally had a cup of coffee. The queen intended to buy a mercury barometer, but Bert told her about the anti mercury law that was coming up soon. Queen Beatrix was shocked, especially because she was about to buy a mercury barometer, being unaware that she would be asked as the queen to put her signature under a law that would prohibit people from buying mercury barometers! She made Bert and Ethne clear in diplomatic words that she thought that law was a bit over the top, but she couldn’t promise anything of course. Anyhow, she obviously must have pulled the wires at a very high level, since only one month later the anti mercury law was suddenly suspended, in spite of the rather negative outlooks. So eventually Bert had won, but for him and Ethne it all came too late. They had already made up their minds, and had decided to leave the Netherlands indefinitely. They put their country house on the market, and sold it within a week.
The Barometer Museum closed down in October that year. In the 12 years of its existence more than 150,000 guests had visited it, which is quite a lot for a small private museum that always wanted to work without grants. The last pages in the guest book were bubbling over with emotional comments from the visitors about the loss of that small museum they had loved so much, that house with such a lot of history and a royal touch, with all those beautiful floral arrangements made by Ethne. An enthusiastic visitor took some photos, wrote an article about the closing museum and put it on his website. Language: DUTCH. www.nicospilt.com/barometermuseum.htm
Left:Beatrix, Queen of the Netherlands amidst Bert, Ethne and daughter Puck. Right: Ethne made this floral arrangement for the royal visit.
It was a heart-warming grand finale of a wonderful time Bert and Ethne had experienced in their museum, with Queen Beatrix as their last important client.
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