by clicking the arrows at the side of the page, or by using the toolbar.
by clicking anywhere on the page.
by dragging the page around when zoomed in.
by clicking anywhere on the page when zoomed in.
web sites or send emails by clicking on hyperlinks.
Email this page to a friend
Search this issue
Index - jump to page or section
Archive - view past issues
News Bulletin : ADA News Bulletin December 2010
43 DECEMBER 2010 AN ECHO OF COO-EE There was a story about 'Coo-ee' in the October CH column. Additional information of interest is now to hand. The 21 November 2009 New Scientist carried a full page of discussion explaining why the call is so audible over a distance. The following is a synopsis: 'Goo-weet' was devised by Australian Aborigines for gaining long distance attention... The highest part of the call is generally between 1 and 4 kHz, and humans hear much better at that pitch...'coo-ee' is more audible because 'coo' opens the throat and allows it to resonate, and the 'ee' resonates in the mouth and nasal cavity... the two vowel sounds are opposites, the 'oo' has almost no overtones, and the 'ee' is rich in them, and when sustained, this avoids 'multi-path distortion'... 'coo-ee' is similar to the Alpine yodel 'odel-ay-itee' and is as effective in communicating over distance. Whatever the reasons, stick with it. It is quintessentially Aussie. JEW'S HARP Your Recorder was listening to classical music on radio (2MBS FM) recently, and was simply amazed to hear an entire Concerto for the Jew's Harp and strings, composed by Johan Georg Albrechtsberger (1736--1809). It sounded strange at first, but after a few bars, it became very enjoyable. He then consulted Google, and was surprized and enlightened by what he found. Also commonly called the Jaws harp, or the Mouth harp, it is seldom seen or heard these days. Many racial groups use it in their folk art and traditions, and give it a variety of other names. It may be one of the world's earliest musical instruments, and dates back at least 2,000 years. The frame of the instrument is held between the front teeth, and its projecting flexible reed plucked with the finger to produce a characteristic 'twang'. The oral cavity acts as a resonator, and a tonal range of about an octave can be achieved by moving the tongue to alter the resonating volume. To find out more, and to hear examples, just Google <Jew's Harp>. It may come as a surprise to many, but Jews harps are made in the keys of D, Eb ,F and G. How can this be, when the predominant note depends on the steplessly variable volume of the oral cavity? The frame is apparently like the drones on bagpipes, and produces a fundamental note behind the twang of the plucked reed. Skilled players say it sounds best if this fundamental matches the key in which the music is played. Your Notary thought that because of its close association with the teeth and the oral cavity, a sound knowledge of the Jaws Harp and its history and operation is essential to be a fully-informed dentist. PANDEMONIUM Your Wordsmith paid scant attention to this word until he read Carl Sagan's The Demon-Haunted World, subtitle Science as a Candle in the Dark (ISBN 0 7472 5156 8), which discusses witchcraft, the human folly attached thereto, and how scientific thinking has all but eliminated the horrible excesses of burning heretics at the stake. He points out that 'pandemonium' is actually Greek for 'demons everywhere'. The sad thing is that there are places where they still thrive. Witchcraft is still out there, especially in Africa. CLIMATE CHANGE Nearly all climatologists agree that the Earth's temperature is rising, but there are some who do not think it is caused by an increase in the man-made greenhouse gas, carbon dioxide. But we are warming, and we are in trouble, because glaciers are retreating, sea temperature and levels are rising, and the Arctic tundra is melting. This last is very worrying, as this melting releases methane, which has, according to one measurement of equivalence, 25 times the long-term greenhouse gas effect as carbon dioxide. There are many scientific papers reporting the melting of the Arctic tundra and the related release of methane, but the one that is really convincing is reported in the May 2010 Scientific American, pages 48-55. Sixty years ago, the Americans were worried about running out of oil and decided to survey Alaska's North Slope for possible sources of fuel. They took thousands of high quality pictures using a large format K18 camera in a low-flying aircraft. They recently decided to scrap these photographs, but Matthew Sturm heard about this, and managed to obtain about 6,000 of the images, which were of Ansel Adams quality.† Matthew and his team then flew in a helicopter and matched the earlier views as best as possible for comparison, and were able thereby to prove that the tundra is retreating, drying out, suffering insect damage and becoming increasingly shrubby and jungle-like. The change is dramatic, and the bottom line is that the methane trapped in the tundra is being released into the atmosphere. Related papers by others report that frozen lakes in the area are melting and allowing methane frozen in layers under the lakes to be released. Our planet is in trouble. You can help a little by installing solar heating for hot water and solar panels for feeding electricity back into the grid. With our sun-lit country, it makes good sense. If awholelotofusdoit,wemaynotneed more coal-fired power plants. ACID RAIN Newspapers and radio and television programmes have, for the last several decades spoken about acid rain, which has caused serious problems in many industrialised countries. Industrial sulphur emissions from burning coal, usually sulphur dioxide, forms sulphuric acid, which kills trees and erodes the surfaces of statues and buildings. We now have another acid rain to contend with, nitric acid, formed from various nitric oxides, which form nitric acid. It is just as corrosive as sulphuric acid, and is produced, not only by fossil fuel burning, but also by motor vehicles, fertiliser manufacturing and the fertilisers reacting with the soil. THE WRONG WORD There are two main types of electric light sockets, the bayonet and the Ediswan (screw). Popular usage has changed Ediswan to Edison, but this is incorrect, and unfair to Joseph Swan, who was the inventor of the incandescent electric-light bulb, and patented it before Thomas Alva Edison. The two joined forces, and Swan gallantly allowed Edison to have the US market, while Swan kept the UK market. Their collaboration endures as the Ediswan, the original screw-fitting for electric-light bulbs, and still used in the US. The bayonet fitting is the norm in the UK and Australia. If you require the former, be pompous and pedantic and ask for an Ediswan-screw bulb. The shop assistant will probably correct you, but now you know how to correct her/him. They may not believe you, because the package is probably labelled, incorrectly -- 'Edison'. LONGEST STAY IN SPACE The holder of the record is Buzz, not Buzz Aldrin, but Buzz Lightyear, of Toy Story fame. The Disney Buzz spent 15 months on the International Space Station, and returned to earth, unharmed, on 11 September 2009. Disney World's Magic Kingdom in Orlando, Florida organized a ticker tape parade for him, and they contrived to get the real astronaut Buzz Aldrin to lead it. Well, they would, wouldn't they? It was somewhat courageous of Disney, really, because there are lots of US citizens who believe in alien visitors, and almost as many who think that the moon landings were filmed on a Hollywood back lot. Too †Ansel Adams was a famous US photographer. Google him to see some of his pictures. clinical hints
ADA News Bulletin November 2010
ADA News Bulletin February 2011