The Hidden Danger When Buying Antique Clocks, Watches, Barometers and Thermometers

Recently I visited the beautiful market town of Hawes in the Yorkshire Dales in Northern England and was delighted to come across an antique shop which specializes in antique clocks, watches, barometers and thermometers. All their antique clocks, watches, barometers and thermometers were carefully restored and sold with a guarantee.  The wonderful array of products on display looked like brand new. I was very excited about the collection.

This antique shop is a family run business established nearly 30 years ago who have always prided themselves in providing customers with a fantastic choice of quality original antiques at competitive prices. Their display of superb long-case, bracket, grand-father and mantle clocks was fantastic and they seemed to have one of the largest choices of barometers and thermometers I have ever seen.

But herein lies the hidden danger associated with antique clocks, watches, barometers and thermometers A large proportion of the antique thermometers on display were mercury thermometers. As a professional Microbiologist I immediately became concerned especially when the person I was with chose an elaborate Antique clock with a barometer and a mercury thermometer barometer and wanted to carry it with him as hand luggage on our flight back to Sydney, Australia.

 

Neither my friend nor the owner of the shop seemed to be aware of the dangers of mercury. Mercury is a heavy metal with the chemical formula Hg and is highly toxic and corrosive. Mercury poisoning include damage to the brain, kidneys and lungs resulting in several diseases including acrodynia, Hunter-Russell syndrome and Minamata disease. 

In mercury thermometers it is used in its liquid form. Mercury is a shiny, silver-white metal that is liquid at room temperature. The glass mercury thermometer consists of a large bulb containing the liquid mercury which is attached to a glass tube of narrow diameter. Therefore the volume of mercury in the tube is much less than the volume in the bulb. The volume of mercury changes slightly with temperature and this small change in volume drives the narrow mercury column a relatively long way up the tube.

Whilst it is encased in the glass it is quite safe. However the glass bulb and tube are very fragile and easily subject to breakage and obviously if broken the mercury is released. The liquid metallic mercury or quicksilver as it is commonly known is poorly absorbed by ingestion and skin contact but it is hazardous due to its potential to release mercury vapor. If not sealed off, mercury slowly evaporates into the air, forming a vapor. The quantity of vapor formed increases as temperatures rise.

In humans, approximately 80% of inhaled mercury vapor is absorbed via the respiratory tract from where it enters the circulatory system and is then distributed throughout the body. In trials it has been proven that chronic exposure by inhalation, even at really low concentrations can cause effects such as tremors, impaired cognitive skills, and sleep disturbance. Acute inhalation of high concentrations causes a wide variety of cognitive, personality, sensory, and motor disturbances.

 Toxic effects of mercury may also be caused by things like amalgam fillings and mercuric salts which contaminate certain fish species. Mercury occurs inorganically as salts such as Mercuric Chloride. Mercury salts affect primarily the gastrointestinal tract and the kidneys causing severe kidney damage.   However, as they cannot cross the blood-brain barrier so they do not usually cause neurological damage without continuous or heavy.

Mercury is listed as a corrosive by the US Dept. of Transportation and must be shipped as a hazardous substance. So simply carrying a mercury thermometer as part of your hand luggage is not allowed internationally or domestically and there are strict regulations about how it can be transported or posted. You need to contact your local authority before purchasing, posting or receiving a mercury thermometer. 

In 2012^[update], many mercury-in-glass thermometers were used in the sciences such as meteorology and microbiology. They were also really common in medical “fever” thermometers and antique wall thermometers such as the ones I saw in this antique store.  However they are being phased out and are becoming increasingly rare. Many countries have banned them for medical use due to the toxicity of mercury. Some manufacturers use alcohol, galinstan, a liquid alloy of gallium and indium, or tin as a replacement for mercury.

Mercury poisoning can be prevented or minimized by eliminating or reducing exposure to mercury and mercury compounds. To that end, many governments and private groups have made efforts to regulate heavily the use of mercury, or to issue advisories about its use. Many countries have regulations or recommendations on the selling and use of mercury thermometers. For example the UK where these mercury thermometers were on sale follows the European Union directive 2007/51/EC on mercury thermometers which came into force on 3 April 2009.  

The UK Health Protection Agency  (HPA) reported that mercury thermometers could no longer be sold to the public. Shops holding stocks of unsold thermometers had to withdraw them from sale but that mercury thermometers purchased before this date could be used without legal implications. The purpose of these restrictions is to protect the environment and public health by decreasing the amount of mercury waste released. The USA Environmental Protection Agency recommend that alternative thermometers be used in the home.

The export from the European Union of mercury and some mercury compounds has been prohibited since 15 March2010.  However the variability among regulations and advisories is at times confusing for the lay person as well as scientists.

 Previously in 2007, the HPA had released a guide to dealing with small spills of mercury, and it is my advice that anyone with a mercury thermometer in their home should read these guidelines and purchase a mercury spill kit and learn the safe way to deal with a mercury spill.

So if you intend to buy an  antique clocks, watches or barometers with an attached mercury  thermometers beware of the hidden danger of mercury and only choose a thermometer if it is alcohol based.

Sundials in the Ticino Region in Switzerland

Sundials featured on all the village churches in  Maggie Valley Located in the  Ticino Region in the South of Switzerland. Is this an early indication of the Swiss horological excellence which was to follow in later years?

 

 

 

I recently visited the land of my ancestors, the village of Gordevio which is located in the Swiss Alps in the Ticino Region in the south of Switzerland. The area has retained its heritage and is spotted with small villages of houses made from the local rocks found in the rivers and on the mountains.

 



 

 

 Every village has a scattering of fountains which were the source of water for the villagers, and a church for worship. These churches are very old, some dating back to as early as  the 15^th , 16^th  and 17^th centuries  are elaborately decorated with frescoes and each has a bell tower. Also common in the area are shrines or grottos dedicated to the Virgin Mary, but many of these were erected in the early 1900’s rather than during the time my ancestors were living there.

 



 But what struck me most (excuse the pun) were the sundials found on each church. Early evidence I think of the Swiss’ fixation on horology and timekeeping.

 

My great great grandfather and his 17 year old son my great grandfather left this amazing land in the 1860’s, driven by poverty and lack of food to the shores of Australia and finally New Zealand in search of the elusive gold to feed their wives, children and families. The area looks more like Hobbit territory than Otago in New Zealand where this great series by director Peter Jackson was filmed. This amazing mountainous area is so beautiful with the snow capped Alps as a backdrop and laced with rivers, lakes and waterfalls and  not to mention the greenest of  green pastures and vegetation sprinkled with spots of vibrant color from the many flowers growing there. Hydrangeas, geraniums and others were so intensely colored like I had never seen before. It is easy to see why my great grandfather chose Otago to settle in. My great great grandfather chose to return to his family in Gordevio.

 

Sundials are devices that tell the time of day by the position of the sun. In the more common designs such as the horizontal sundial, the sun casts a shadow from the style onto a surface marked with lines indicating the hours of the day. Interestingly though sundials do not adjust for daylight saving and we found that the sundials we saw in Switzerland in June were an hour out.

 

 

The part of sundials which casts the shadow in order to tell the time is called a gnomon. The style is the edge of the gnomon and is usually a thin rod or a sharp, straight edge. As the sun moves across the sky, the shadow-edge aligns with different hour-lines. All sundials must be aligned with their styles parallel to the axis of the Earth's rotation to tell the correct time throughout the year. The style's angle from the horizontal will thus equal the sundial's geographical latitude.  Note that inexpensive mass-produced decorative sundials usually do not have  the correct hour angles and  cannot be adjusted to tell correct time so they can only be used for  decorative purposes.

 

Apart from these sundials there was plenty of evidence with Switzerland’s fixation on horology and their enthusiasm for horological excellence. Watch shops selling all the best of Swiss watch brands were everywhere and the displays in the shops were amazing. The testimony to this is Baselworld which I discussed in my previous blog. A trip to this beautiful southern area of Switzerland and Northern lake district of Italy is well worth the effort. Amazing scenery, amazing architecture, amazing churches, amazing shrines to the Virgin Mary and amazing sundials..