Thursday, November 29, 2012

Swing Bowling

In most top class cricket teams today there is at least one swing bowler, one who can move or “swing” the ball from its initial line in the air, producing a difficult situation for the batsman, both from a scoring point of view and also just to survive at the crease.

One of the earliest exponents of swing bowling was the great Australian pace-man Frederick “The Demon” Spofforth (1853 – 1926), who began his spectacular Test career in 1877 at express pace, but later switched to variation in his bowling, including a mean in-swinger that produced plenty of wickets. 

Frederick Spofforth (1853 to 1926)
Test bowler for Australia - known as "The Demon"
(Image form Wikipedia Commons)

Known as “swerve” in the 19th century, it was further developed over the years and is now recognized as one of the main weapons in the arsenal of the fast medium bowler. The English quick James Anderson is recognized as one of the great swing bowlers of the present time.

Swing bowling is very much an art, and is produced through several different factors, including the way the ball is held on delivery, the nature of the shine on the ball, and perhaps a little more surprisingly, the weather.

English fast bowler James Anderson - a noted swing bowler
(Image form Wikipedia Commons)

Bowling a swinger basically depends on the position of the seam on the ball through the delivery and this results in one side travelling through the air faster than the other. This is encouraged by polishing one side of the ball and assisted by the prevailing atmospheric conditions such as temperature, humidity, cloud cover, together with wind speed and direction.

The denser the air, the more swing is encouraged, so cooler air is a more fertile swing environment than warmer air. Up until quite recent times it was also believed that high humidity helped in encouraging swing, but new research has revealed the rather surprising fact that cloud cover may be far more important. In bright sunlight hot air rises from the surface of the pitch, creating a turbulent environment for the ball to pass through, which reduces swing. In overcast conditions there is less rising air, less turbulence and more swing.

All this means that cool, overcast weather is best for swing bowling and the swing can also be magnified if there is some component of the wind blowing across the wicket in the same direction in which the ball is swinging.

These conditions are met with far more often in England than Australia where hot and sunny weather is the norm during the summer months, but on occasion good swing bowling weather can emerge here as well. In the southern capital cities of Australia, such as Adelaide, Hobart, Melbourne and Sydney, this can happen in a southerly airflow following a cold front, when temperatures fall and cloud cover increases.

One of the greatest exhibitions of swing bowling ever seen was by the Australian Bob Massie in the Second Test at Lords in England during the 1972 Ashes tour.

In cool and cloudy conditions, Massie, coming alternately over and around the wicket, bent the ball through the air so prodigiously that many of his deliveries were virtually unplayable and the English batting was routed. His figures over the two innings were 8/84 and 8/53, representing match figures of 16/137, the third best test match figures of all time.

Massie’s display was a convincing demonstration of the tremendous potency of swing bowling, achieved when the bowler is on song and the atmosphere is just right for the purpose.

Great footage of Massie’s bowling during this Test can be seen at

Tuesday, November 13, 2012









悉尼和墨尔本周围的大多数中国反对共产主义和不支持毛泽东政权在20世纪60年代,但在过去的三十年中,政治的情况已经淡化。在悉尼唐人街附近的语言反映了这一点 - 在60年代和70年代,这是几乎所有的粤语,但现在是压倒性的普通话。








所以约翰(1946 - ):中国的澳大利亚商人,并两次当选市长的墨尔本市

黄英贤(1968 - )澳大利亚参议员代表南澳大利亚州和一个联邦部长吉拉德政府

Sunday, August 12, 2012

In Flight Air Turbulence

One of the nagging worries with any aircraft flight is turbulence. It sometimes strikes without warning and can produce a frightening experience for even the most seasoned of fliers.

Mostly turbulence is only minor – a series of “bumps” that might last for a few seconds - but at the other end of the scale it can be far more serious. Major and abrupt vertical and horizontal changes in the position of the aircraft can throw loose objects and even people, around the cabin with injuries sometimes resulting. And at the extreme end of the spectrum turbulence can produce structural damage to the aircraft and in some very rare cases result in an aircraft accident.

Turbulence has four broad categories:

(1) Light: slight “bumpiness” but with little of no discomfort for passengers.

(2) Moderate: Passengers walking down the aisle will be moved off track; loose objects in the cabin will move about.

(3) Severe: Any standing passengers will be thrown off balance. Loose objects will pitch onto the floor.

(4) Extreme: Unsecured passengers thrown violently about – they may strike the roof or lateral areas of the cabin. Loose objects turn into interior missiles.

Cases three and four are quite rare but when they do occur can cause injury to passengers or cabin staff. In Australian airspace we see about between 2 and 3 reported significant turbulence encounters per month, or 24 to 36 per year. In terms of the number of flights and people carried during this time this represents only a very small percentage of flights.

In flight turbulence is caused by small scale currents or vortices in the air that produce “bumpiness” when the aircraft flies through it, similar in some ways to a car driving over a series of corrugations in the road. There are several ways turbulence is produced in the atmosphere.

Thermals: These are rising parcels of air generated by the atmosphere being in contact with a warm surface below (land or ocean). If there is sufficient moisture in the air, cloud will form over these thermals and form billowing cotton wool formations called cumulus cloud. An aircraft flying through this type of cloud will usually experience light to moderate turbulence.

Aircraft flying through cumulus clouds will normally experience turbulence because of the thermal activity. (Click to enlarge)

Thunderstorms: If rising air continues to be generated in a cumulus cloud it can grow to prodigious heights before it finally flattens out, typically at heights of 10 to 15 km above the ground. When the cloud grows to this height it contains regions of powerful “up and down” draughts in which there is a mixture of rain and hail, with lightning and thunder also added to the mix. This is a giant cumulus cloud, more properly called a cumulonimbus and is popularly known as a thunderstorm.

Pilots will avoid penetrating a cumulonimbus cloud because turbulence inside can be severe to even extreme. Fortunately these clouds are highly visible by day and also easily detectable on radar both day and night so are readily avoidable in a modern passenger aircraft.

Moderate to severe turbulence is often encountered within cumulonimbus clouds because of the violent mix of updrafts and downdrafts within. This diagram is not drawn to scale - in reality the aircraft would be less than the size of a pin head here. (Cloud image from Wikipedia Commons, click to enlarge)

An infamous case of thunderstorm penetration involving the loss of an aircraft occurred in November 1961 at Mascot airport in Sydney. See

Mechanical turbulence: As wind passes over the ground, air in contact with the surface is slowed by friction, while the air above continues at the unimpeded speed. This creates many thousands of rolling vortices, and depending on the wind speed and roughness of the terrain, these can extend upwards for a considerable height. Aircraft flying in these regions will encounter “bumpiness” called mechanical turbulence, that is usually only in the light to moderate range.

However in some cases, when strong winds blow over a mountain range, the air can organise itself into large organised waves that extend several kilometres downstream of the mountains. Very powerful rising and falling air currents are often present in these waves and organised bands of clouds sometimes form near the wave peaks. These waves are called lee waves or mountain waves and the clouds are called lenticular because of the characteristic “lens” shape they often adopt. Just as we see with waves on the ocean, mountain waves sometimes topple and break producing circulations called rotors.

Mountain waves (or lee waves) can produce severe turbulence. Clouds sometimes form at the peak of the waves. (Click to enlarge)

Turbulence produced by mountain waves can be moderate to severe, and in extreme cases, the actual destruction of an aircraft has been recorded. Perhaps the most infamous of these was the disintegration of a Boeing 707 jet, Flight 911 that was flying near Mt. Fuji in Japan on February 4th 1966. It is believed that the aircraft flew into an area of powerful mountain waves that produced extreme turbulence and failure of the air-frame. A detailed analysis of this incident can be found at

Wind shear:
Put simply, wind shear is the change of wind speed and direction with height or over a horizontal distance. There is always a degree of wind shear in the atmosphere, but when big changes take place over short distances, significant turbulence can result.

Wind shear turbulence can form when one layer of air slides across another, at a different speed or from a different direction, or both. This can generate wave like disturbances at the interface, called Kelvin Helmholtz waves, and if there is cloud present in this zone, the waves become visible.

Kelvin Helmholtz waves form when the winds above a certain layer (the dotted line here), are stronger than those below. (Image from Wikipedia Commons, click to enlarge)

But in many cases there is no cloud to alert the pilot that unusual atmospheric motion may be present and in these cases the phenomenon is referred to as “clear air turbulence” or CAT.

Jet streams, that are high-speed rivers of air that circulate the globe at approximately 10 to 15 km above the surface, are areas where CAT is often encountered. There are two main jet streams in each hemisphere, the polar jet and the subtropical jet and these meander and change direction as they circle the earth.

The main jet streams of the Earth. (Image from Wikipedia Commons)

Because jet streams are zones of high-speed winds running within the broad-scale atmospheric flow, there are surrounding regions where the wind speeds change quickly with both height and horizontal distance, and this can generate considerable wind shear and therefore turbulence. For more information on jet streams see

To get the issue of in flight turbulence into perspective it should be noted that even the most frequent fliers will never experience severe or extreme turbulence, and that the modern passenger jet is fantastically strong and well able to handle in flight turbulence in all its forms.

But for the passenger, by far the best protection against turbulence is to fasten your seatbelt. When not moving about the cabin keep the belt buckled up, and even if severe turbulence is encountered you will safely ride it out if properly secured. 

Wednesday, June 20, 2012

Darlinghurst Gaol

Any pedestrian visitor walking along Forbes Street, Darlinghurst will be immediately impressed by the tremendous stone walls stretching along the eastern side of the road, punctuated by a magnificent sandstone gateway – in fact the entrance to today’s National Art School.

But for much of the 19th Century this entrance was the gateway to death and damnation for many unfortunate Sydneysiders. For this was the entrance to the infamous Darlinghurst Gaol, a place of brutality, confinement and misery.

The original gaol in Sydney was located in George Street, but by the mid 1820’s was grossly overcrowded, and the conditions so barbarous, that the Government agreed that a new gaol was necessary. A wag noted at the time that at the George street lockup it was so overcrowded that whilst it was possible to hang six people at once, there was only room enough to hang two in comfort. This was classical “gallows humour” at its worst.

A site was chosen on the heights above Woolloomooloo and building commenced for a new gaol, using locally quarried sandstone cut and placed by convict labour to produce a rectangular space surrounded by four huge walls. This was known as the Woolloomooloo Stockade but it was not until 1841 that prison buildings within these walls were partially completed according to a plan prepared by the Colonial Architect, Mortimer Lewis. He based the design on the Eastern Penitentiary in Philadelphia, which featured a central building from which cellblocks radiated outwards, like the spokes of a wheel. 

Plan for the gaol, c 1840 signed by the Colonial Architect Mortimer Lewis. Mitchell Library, State Library of NSW, Call no: SSV1/Gao/Darh/1 - Click to enlarge)

On June 7th 1841 the prison, although incomplete, was ready for occupation and the residents of Sydney were treated to a remarkable procession when the prisoners from George Street were marched through the streets up to their new accommodation – Darlinghurst Gaol. The recollections of an old ex gaol warder, who saw the scene, recalled the events in the Sydney Morning Herald of 9th January 1914:

“On the morning of June 7, 1841, a strange procession passed through the streets of Sydney—119 men in convict garb, chained together, on their way from the old gaol to the new one. "The redoubtable Curran," remarked the "Sydney Gazette," of the period, "heavily ironed, took precedence of his brother culprits." Later in the day, the female prisoners, numbering about 50, passed through the streets”. (The Curran referred to was Paddy Curran – the bushranger who was to become the first man hanged at Berrima Gaol in 1842).

 And so began a period of 73 years when Darlinghurst gaol was the main detention centre for NSW, producing a long and brutal history involving floggings, hard labour, and on 77 occasions the “extreme penalty” of the law, which in those days was execution by hanging.

A "birds eye" view of the Gaol, the Illustrated Sydney News, November 1866. (Click to enlarge)

The Herald’s article of 1914 provided some further detail:

“The first execution at Darlinghurst Gaol took place on October 29, 1841, when George Stroud and Robert Hudson were hanged, the former for murdering his wife, the latter for the murder of a fellow-convict.
In those days, an execution was a public thing, and was witnessed by hundreds of people. It is stated that no fewer than 10,000 people assembled to see the execution of the notorious Knatchbull in 1844. Public executions were abolished in Sydney in 1853, and it was not till 15 years afterwards that they were abolished in England. In all, Darlinghurst has seen 76 executions”.

And by the way, if you think hanging was a humane method of execution, many existing records show otherwise. In several cases, the knot in the rope that is placed behind the ear slips out of position during the drop and instead of the neck being broken, slow strangulation results. In these cases the onset of death can take 15 to 20 minutes. This happened at Darlinghurst with the Mount Rennie executions and with the hanging of Digby Grand, the Auburn murderer.

After only 15 years of operation the gaol had become overcrowded, so an extra wedge of land was purchased at the northern end of the site and a “Y” shaped cellblock was built there. It was in the cleft of this “Y”, that a gallows was built, replacing the makeshift structure that had been used in front of the gaol in public executions, and later in the prison yard when these were abolished. A little later, the circular building at the centre of the complex was completed – with the ground floor a reception area and the upper floor the prison chapel.

Sentry towers were built on top of the walls at the corners and these were manned 24 hours a day. A senior warder described how the guards operated while on sentry duty when they had to call to the senior warder every half hour, even all through the night:

"Half-past 1 o'clock. . . All's well. . . Number one."
The sentry at the gate has spoken.
"Half-past 1 o'clock. . . All's well. . . .Number two."  
And sentry No. 2, revolver at side, proceeds on his rounds. All's well in wings A, B, and C.
"Half-past 1 o'clock. . . All's well. . . .Number three."  
All's quiet at the hospital. "Half-past 1 o'clock. . . All's well . . .Number four."
Nothing suspicious in the Burton-street wing—wing E.
Sentries No. 1, No. 2, No. 3, and No. 4 pass on. The senior warder, attentive and alert, has noted their reports. All's well at the gaol. All's silent”.

The neighbours near the gaol got used to the mournful calls of the sentries that floated over the rooftops of Darlinghurst night and day for 365 days of the year.

A view of the gaol in 1874 from the October edition of the Illustrated Sydney News. (Click to enlarge)

As an interesting architectural feature, a tunnel was constructed that connected the holding cells beneath the adjoining Courthouse with the gaol. The prisoner would enter the tunnel on the gaol side and come up inside the Courthouse and then return by the same path.

As the years passed, construction proceeded, and by 1874, most of the main buildings had been completed. The main gate, opening out on to Forbes Street had been relocated from its original position a few metres up towards Burton Street and entirely remodelled in a rounded “buttress” style. This relocation was to prevent prisoners” rushing” towards the main gate from near the Governors residence.

Many famous and infamous prisoners passed through the gates of the gaol, including the bushrangers Frank Gardiner and George Scott (Captain Moonlite). Scott was executed for his crimes. Other bushrangers who were executed were the two Clarke brothers (hanged in 1867) and John Dunn, a member of Ben Hall’s gang (hanged in 1866).

Then there was Jimmy Governor who was executed in January 1901 for mass murder after a killing spree all across central NSW the previous year.

The infamous Mount Rennie rape case produced a dark climax when four youths, all under 20 years of age, (one only 17) were hanged at the gaol in January 1887, amid one of the great public controversies in Australia’s legal history.

Watercolour of the gaol by the inmate Henry Louis Bertrand, 1891. Bertrand was convicted of the murder of Henry Kinder in 1865 in one of Sydneys most notorious homicides of the time. He eventually served a 28 year sentence, one of the longest in Darlinghurst's history. Mitchell Library, State Library of NSW, Call no: SV1/Gao/Darh/2 - Click to enlarge)

The only woman to be hanged at the gaol was Louisa Collins who was executed in January 1889 for poisoning two of her husbands in order to receive life insurance payments.

Louisa Collins - executed at Darlinghurst Gaol in 1889.
(Photograph from the NSW State Records Office)

Our great Australian poet Henry Lawson also “did time” at Darlinghurst, for unpaid debts and non-payment of alimony. In his haunting poem “One Hundred and Three”, he describes the tough conditions at the prison, referring to it as “Starvinghurst Gaol”, because of the meagre rations given to the inmates.

The severe punishment of a flogging was liberally used at the gaol, right through into the last decade of the 19th century, and was always a brutal form of torture. The horror of a flogging was well caught in the article that appeared in a contemporary newspaper account on 13th February 1895:

The young man, Robert Strong, for brutal assault upon a sailor, received his flogging of 20 lashes in Darlinghurst gaol on Saturday afternoon. From first to last stroke the man utterly broke down. He howled, wept, and prayed; his ejaculations, "Oh, God, have mercy," could be beard outside the gaol wails. When released he was able to walk with difficulty, and it was evident that he bad been effectually cowed, as there was the absence of that mock air of bravado visible as he marched to the whipping post.

Despite the heavy punitive nature of Darlinghurst, common to all 19th century Australian prisons, a real attempt at rehabilitation was also made, through trade training and education. In this respect the gaol was somewhat ahead of its time, particularly in comparison to other capital city gaols around Australia where punishment was placed well ahead of rehabilitation.

The gaol was an industrial prison, with a long line of workshops inside the wall on the eastern side. Diverse activities took place here, including broom and mat making, stonecutting, bookbinding and cobbling. During this work time strict procedures were in place and no conversation was permitted.

The gaol school room - from the Illustrated Sydney news of November 1866 (click to enlarge)

In what was very advanced thinking for the time some of the prisoners were also given instruction in a school room in order to achieve at least basic literacy before release. The Illustrated Sydney News reported in 1866 that the “Hours of labour were from 7 to 8, 9 to 12 and 1 to 4, in all 7 hours. A great many attend school; some one hour, others two hours, thereby reducing the hours of labour…”

There was a prison uniform that in its basic form consisted of a shirt with “Darlinghurst Gaol” surrounding a broad arrow on the back. There were variations of this uniform depending on the time of the year and the place of work of the prisoner.

In the broom factory, showing the broad arrow motif on the back of the prisoners shirts - from the Illustrated Sydney News November 1874 (click to enlarge)

In common with many 19th century prisons, tobacco was the currency within the walls. Friends of the prisoners would walk up Burton Street and throw tobacco packages over the walls where they would be eagerly seized by the inmates. Tobacco was used as trade in all sorts of transactions within the walls, swapping it for food, drink and perhaps for privileges from a corrupt guard.

After many years of increasing difficulty associated with an ever-rising inmate population and nowhere to expand, the inevitable happened and the Government looked for another site for a gaol.

Finally, in 1914, after 73 years of operation, Darlinghurst Gaol was closed and the existing prisoners taken by special tram out to the new accommodation at Long Bay. During the First World War Darlinghurst was used as an internment camp for Irish and German nationals, and then in a remarkably enlightened move it was transferred to the NSW Department of Education.

Above: The interior of the Darlinghurst gaol chapel c 1880. The stained glass windows were removed and taken out to the new chapel at Long Bay in about 1913. They were then returned to their original location in Darlinghurst in 1981. Mitchell Library, State Library of NSW, Call no: SPF/168 - Click to enlarge)

After extensive renovation it was born again in 1921 as East Sydney Technical College, and since 1995, the National Art School. Today the buildings remain externally intact and form a unique example of a complete 19th century Australian prison complex. 

 The gates to the National Art School today - once the entrance to the dreaded Darlinghurst Gaol.
Image from Wikipedia Commons (click to enlarge)

Left: The shirt design motif worn by prisoners c 1880. 

References: Hope in Hell - Deborah Beck, Allen and Unwin, 2005

For a great series of contemporary images see

Sunday, June 10, 2012

Heat in Cars

Heat in Cars

During the warmer months it's a good time to remind ourselves about the dangers of locking children or pets in cars parked outside, particularly in bright sunlight.

It’s often tempting to do this, perhaps to pop into a shop for just a few minutes, without all the hassle of buckling and unbuckling seatbelts and arranging prams and strollers.

However even a short time can be extremely dangerous, particularly during the summer months. Tests have shown that on a 30C (86F) day, as measured in the shade, a car parked in the sun can heat up from 20C (68F) to 44C (111F) in only ten minutes. After 20 minutes, temperatures inside the same car can hit 60C (140F).

Temperatures can ramp up to 60C (140F) inside a car parked in the sun in less than half an hour.

The shape of the car, its colour, interior type and the amount of window and windscreen glass also affect the way the vehicle heats up, as do other variables such as cloud cover, wind and the angle of the sun. But the effects of these are usually quite minor and any vehicle parked outside on a hot day will heat up quickly. And contrary to popular opinion, leaving the windows partially down does not solve the problem – it may just slow the heating process slightly. There is no safe way to do it.

Even hi-tech modern vehicles, such as this Honda Civic, can heat up to dangerous interior temperatures when parked outside during bright sunlight conditions. (Image from Wikipedia Commons - click to enlarge)

But perhaps of even greater significance is that controlled tests have also revealed that we don’t need very hot weather to produce dangerous temperatures inside cars; even in mild conditions of around 22C (72F), interior temperatures can rapidly ramp up to 40C (104F) plus in less than an hour in bright sunlight conditions.

Small children confined in these sauna-like temperatures can dehydrate rapidly, and suffer an onset of hyperthermia, where the core temperature of the body rises to dangerous levels, above 40C (104F) on occasion. This can create a serious and sudden medical emergency with hospitalisation required, and in extreme circumstances fatalities have occurred.

In the United States, where these figures are readily available, more than thirty children die each year of heatstroke, after having been locked in cars parked outside. There are probably numerous examples of pets dying under similar circumstances.

So the summer message is clear – don’t expose your children or pets to these risks, even for a short period of time.

Wednesday, May 30, 2012

Defining the Seasons

As we move between the solstices and equinoxes it is sometimes asked how we measure the start and end of the seasons in Australia and why this is different to other parts of the world.

In Australia we use the beginning and end of calendar months to describe our seasons – winter is June 1st to August 31st, spring from September 1st to November 30th, summer from December 1st to February 28th (29th in a leap year) and autumn from March 1st to May 31st.

However in other parts of the world the seasons are defined through the solstices and equinoxes. In the Southern Hemisphere the summer equinox, or the longest day, falls around December 21, and the winter solstice, or shortest day, around June 21. (There is some minor variation of these dates from year to year). The spring or vernal equinox (equal hours of night and day) falls around September 21st and the autumnal equinox around March 21st.

Darwin thunderstorm - common during the southern hemisphere summer. (Image form Wikipedia Commons - click to enlarge)

If we use these dates to define our seasons we find that summer occurs between December 21st and March 21st, autumn from March 22nd to June 21st, winter from June 22nd to September 21st, and spring from September 22nd to December 20th. This system displaces our present seasons forward by about three weeks.

So why did Australia not adopt this solstice – equinox system rather than the calendar month option that has considerably less physical significance? The answer appears to be lost in the mists of time but an interesting theory has been advanced that may or may not be true.

In 1789 the New South Wales Corps was formed in England as a permanent regiment to oversee the infant settlement of Sydney. Apparently they changed from summer dress to winter dress on March 1st of each year and then back to summer dress on September 1st. This may have been the reason behind defining our seasons using calendar months. 

In any case it’s also become rather obvious that the four season European model has little relevance in many parts of Australia. In Darwin, for example there’s a strong wet season dry season cycle with spring and autumn hard to find.

Indigenous Australians have a different way of describing the seasons that varies from place to place and some further details about this can be found at

Sunday, April 29, 2012

Delegation - A Story of Flagpoles

One of the most important functions of a manager is to facilitate the so-called process of delegation - this is defined and discussed in the online resource “Management Study Guide” at 

“A manger alone cannot perform all the tasks assigned to him. In order to meet the targets, the manager should delegate authority. Delegation of authority means division of authority and powers downwards to the subordinate. Delegation is about entrusting someone else to do parts of your job. Delegation of authority can be defined as sub division and sub allocation of powers to the subordinates in order to achieve effective results”.

Despite the simplicity of the concept of delegation, it is one of the most difficult management functions to balance effectively.

The two extremes of management style are:
  1. The micro manger – he or she does not delegate and prefers to perform all the tasks personally. This can be a sign of distrust in the ability of the subordinates. By using much of the available time in performing subordinate’s work, the micro manager does not give enough attention to the big picture that can languish as a result. 
  2. The hands-off manger – he or she is interested only in the big picture and is not greatly concerned with supervision of the subordinates work. The quality of this will often suffer as a consequence.
Most managers fall somewhere in between and it is one of the most difficult tasks to find the right balance – a balance that will vary in each type of corporation.   

I learned a very valuable lesson on delegation when I was in the military – we were performing aptitude tests for officer potential and one of the problems we were given went like this:

Task: You are to erect a flagpole 100 feet high.
Personnel: You have at your disposal a platoon– 1 sergeant, 3 corporals and 3 sections of soldiers, 10 in each section.
Equipment: There are three lengths of rope provided, each of which is 200 feet in length. The rope cannot be further subdivided. You also have 3 sledgehammers and 3 steel pegs, each two feet long.
Describe how you would erect the flagpole.

My solution was probably the most common one suggested from individuals in the group. 

“After tying the three lengths of rope to the top of the flagpole, each section of men, under supervision of the corporals, then marches outwards to form an equilateral triangle – with the flagpole at the centre. The sergeant would then supervise the hoisting of the pole and driving the pegs into the ground at the right positions.   
My solution to the flagpole problem
(Click to enlarge)

Several other methods were suggested, all containing various degrees of complexity and practicality, but none described the solution the Army was actually looking for - which was simply this. 

You issue the following order  – “Sergeant, have the men erect the flagpole”.

This is a perfect example of delegation. To attain the rank of Sergeant in the Australian Army, you have to be a very capable and practical individual, well able to solve problems of the flagpole type. The Sergeant can therefore be entrusted with the task, leaving you, as the officer, free to engage in other work.

Above: One of the world's tallest flagpoles, located in Amman Jordan. It is 126.8 m (416 feet) tall.  (Image from Wikipedia Commons - click to enlarge)

This principle can be carried across to all corporations, but if you can’t trust your subordinates, it can mean that there are problems in the recruitment or promotion system within your organisation. Or it can mean, that as a manager, you will have to learn to trust others – one of the most important assets of leadership, both in the military and in civilian life.

Monday, April 23, 2012

Rain on Your Wedding Day

Over recent years outdoor weddings have become increasingly popular, and events held by the sea or on mountain peaks for example, can provide spectacular backdrops for that very special day. However it also means that the weather becomes a major factor in the equation and this is often a difficult issue.

Outdoor wedding ceremonies are subject to the vagaries of the weather. (Image from Wikipedia Commons)

The fundamental weather problem emerges in the early stages of planning – weddings are normally organised several months ahead, but reliable forecasts for a given location ore normally only possible out to a week ahead. This mismatch of time intervals often causes substantial grief both to the wedding organisers and to the meteorologist who is called on to produce the weather forecast for the ceremony. 

Many of my numerous grey hairs have been produced from wrestling with this problem and I’ve found that one of the most dangerous life-forms in the jungle is a wet bride with her wedding dress trailing in un-forecast mud.

So are there ways around this dilemma? Well firstly, planning should take into account the long term climate averages – these can readily be obtained online and will give you some idea which are the wettest, driest, coldest and hottest months in your area of interest. However the problem with this is that on any particular day, average conditions are not always encountered. Remember Mark Twain’s observation – “Climate is what we expect, weather is what we get”.

Secondly, and most importantly, always have a plan “B” ready to go.
This simply involves organising access to a shelter nearby should rain develop on the day. This will take a lot or stress out of the decision-making and also off the meteorologist who is sweating this out with you.

Outdoor wedding ceremonies were practiced over many centuries across different cultures. This contemporary painting shows the wedding of the great Mughal Emperor Shah Jahan, circa 1630. Fireworks accompanied the ceremony throughout the night. (Image from Wikipedia Commons)

Then thirdly, start watching the weather forecasts 7 days out from the wedding – monitor these on a day to day basis and this will help you “fine tune” your arrangements. The forecasts tend to become more accurate the closer we get to the actual day.

Finally, I always fall back on my last defence which is the old belief, common to many cultures, that it is good luck if it rains on your wedding day. This relates to the association that rain has with the fertility of trees and plants, and the refreshing effect it has on the atmosphere.

In Hindu tradition rain is good fortune because a wet knot - the knot of marriage - is harder to undo than a dry knot. The Italians, have a wonderful saying “Sposa Bagnata, Sposa Fortunata,” which means “Wet Bride, Lucky Bride.” However many brides-to-be are not reassured by this knowledge.

Interestingly, in some parts of the world, it is law that the marriage ceremony must be performed under a roof, and this makes life a lot easier for the local meteorologists. If ever I run for Parliament that will be my main policy plank and, assuming I have the numbers, I’ll institute it immediately I become Prime Minister.

Thursday, April 19, 2012

The Amazing François Viète

François Viète (1540 -1603) was one of the foremost mathematicians of the early Renaissance era.

Born into the French upper middle class, he became a lawyer by profession but his high intelligence allowed him to excel in several fields, including mathematics, astronomy and geography.

During the period when Spain and France were at war Viète broke the Spanish military code allowing the French to read secret dispatches. The Spanish King accused the French of using sorcery against him.

François Viète - great French scholar and mathematician.
(Image from Wikipedia commons)

But it was in mathematics that Viète was to leave his greatest mark. Investigating methods of generating π, the ratio between the circumference of a circle to its radius, he discovered one of the classical formulae of mathematics that today is called Viète’s equation. It was one of the very early formulae involving infinite products and nested square roots.

                      .             2               .              2                  .....   =  π//2     
             √(2)              √(2+√(2))           √(2+√(2+√(2)))                         

Inspired by Viète I've been playing around with nested square roots over the last few years, and the results I've come up with are below. The 5th result contains a generalisation for pth roots, and the 6th is a generalisation of Viète's equation

No proofs are included but I thought the results themselves may be of some interest to a mathematician out there.

1.        If  x(n+1)=√(2+xn)  ,  x0=x, n=0,1,2,3…

            then xn=2cos((cos-1(x/2)/2n)) for |x|≤2
            and lim xn = 2.

            Also, for x>2,


2.        If xn+1=√(2-xn)  ,  x0=x, |x|≤2, n=0,1,2,3…

           then xn=2cos(π//3+(-1/2)n (cos-1(x/2)- π//3))

           and lim xn = 1

3.       If  xn+1= (√2/2)(√(2+xn)+√(2-xn))  ,  x0= x, |x|≤2, n=0,1,2,3…

          then xn=2cos(π//6+(-1/2)n (cos-1(x/2)- π//6))

          and lim xn = √3

4.         1  .           1           .                1             ……….  =  √3      
           √2       √(2-√2))             √(2-√(2-√2)))                       2

5.      If xn+1 = {( xn+√ (xn2-4))/2}1/p + {(xn-√ (xn2-4))/2}1/p

         then xn=2cos((cos-1(x/2)/pn)) for |x|≤2, and

         xn=2cosh((cosh-1(x/2)/pn)) for x>2, 

6.                   .              2               .              2              ..   =  arcos(x/2)  
             √(2+x)      √(2+√(2+x))          √(2+√(2+√(2+x)))         (1-(x/2)2)
              for |x|<2

Tuesday, April 17, 2012

The 1948 London Olympic Games

Following the dark years of World War Two, when two successive Olympic Games were missed (1940 and 1944), a triumphant return was held with the London Olympic Games of 1948.  59 Nations participated but Germany and Japan, under Allied military occupation at the time, were not permitted to compete. The USSR chose not to do so.

 The official logo for the 1948 Olympics (Image from Wikipedia Commons)

That the games were held in London was a story in itself. Before the war the city had been selected to host the 1944 games but the war derailed this plan. The war had been over for nearly 3 years by 1948, but shortages of all types persisted in England, including food, petrol and accommodation and many were sceptical that London could successfully stage the Games.

However using much improvisation, the Organising Committee overcame all the problems. In marked contrast to the massive expenditure of recent Olympics, the London budget was miniscule. A special Olympic Village was deemed too expensive and instead, male athletes were housed in existing wartime RAF camps and female athletes in various London Colleges. As a result of these measures the 1948 Olympics became known as the “Austerity Games”.

On a sparkling summer day on 29th July, the Games were opened at Wembley Stadium before a crowd of 85,000 people and presided over by King George V1. The athletes paraded through the stadium, led by Greece and followed last of all by the athletes of the home country – the United Kingdom. And for the first time an Opening Ceremony was televised live and transmitted across the BBC network.

 An advertising poster for the Games (Image from Wikipedia Commons)

The Games concluded on 14th August 1948 and proved to be a resounding success. For the war weary world that participated they marked the start of an era of peace and general prosperity for the next decade.

Later this year London will become the first ever city to host the summer Olympics three times – in 1908, 1948 and 2012.

Olympic showcase:

One of the star athletes of the London Games of 1948 was the extraordinary Dutch athlete Fannie Blankers – Koen, who was then the mother of two children and competing at thirty years of age.

             Statue of Fannie Blankers – Koen in a park at Rotterdam
(Image from Wikipedia Commons)

Nick-named the “Flying Housewife” she won four athletic gold medals at London – the 100 and 200 metre sprints, the 80 metre hurdles and was also a member of the victorious Dutch team in the 4x100 metre relay.

And along the way she proved several people wrong – before the games it was said that thirty was too old for elite athletics, and that anyway she should be home looking after her family. Remarkably it was later revealed that during her London triumphs she had been pregnant with her third child, eventually born in early 1949.

Blankers-Koen had competed in the 1936 Berlin Olympics as an 18 year old, and following London also competed at the Helsinki Olympics in 1952. She also ended up winning 58 national titles in Holland and was voted the “Female Athlete of the Century” by the International Association of Athletics Federations in 1999.

Her stellar career finally ended with her death in January 2004.

Thursday, February 2, 2012

I'm A Barbie Girl

It’s no secret that pop music is big business, and a top 10 hit will normally rake in millions of dollars for the artists and record company concerned.

Because of these big dollars, legal issues sometimes arise that are fought out vigorously in court, with two famous examples involving allegations of plagiarism.

In the 1970’s a prolonged legal battle was fought over ex Beatle George Harrison’s song “My Sweet Lord” when it was alleged that this had been copied from the Chiffon’s 1963 hit “He’ So Fine”. 

George Harrison in 1987 (Image from Wikipedia Commons - click to enlarge)

In 2009, it was alleged that part of the famous Australian hit “Land Down Under” had been taken from the 1930’s children’s song “Kookaburra”, and this too resulted in lengthy legal proceedings.

But probably the strangest legal case ever to arise from a pop tune was not fought over plagiarism but over a far more esoteric matter that those in the marketing world call “branding”. And it all came about like this.

With little doubt, the most successful toy doll ever made is the celebrated “Barbie Doll”, first launched by the American company Mattel, back in 1959. Through many years of clever marketing, the Barbie brand became immensely popular around the world, with a wide variety of Barbies made available together with a large range of clothes and accessories. Barbie also had a male companion called Ken and the entire arrangement was marketed as a sparkling and wholesome experience for young girls, typically in the age group from 3 to 12.

A range of Mattel's iconic Barbie Dolls - probably the most commercially successful dolls ever. (Image from Wikipedia Commons - click to enlarge)

And the enormous success of the Barbie brand also attracted attention in other ways. In 1997, the Norwegian dance music group “Aqua”, working for MCA Records, put together a novelty song, “I’m a Barbie Girl”, which was a fun parody of a day in the life of Barbie and Ken. Accompanied by a catchy tune, music video and loaded up with raunchy double entendre lyrics, the song, against all expectations, rocketed up the charts, becoming a number 1 hit for three weeks in a row in both the UK and Australia. It also reached an unprecedented number 7 in the US Billboard Hot 100, thereby joining the big league of pop music and ultimately selling more than 8 million copies.

Aqua's "Barbie Girl" cover. (Image from Wikipedia Commons - click to enlarge)

Nearly everyone was delighted but there was one major exception. Barbie’s maker Mattel was far from amused with what it claimed were undesirable images of Barbie and Ken that were promoted by the song and video clip.

Mattel alleged that the song portrayed Barbie as a sex object (referred to as “a blond bimbo girl” in the song) and that her image was tarnished by the inferences contained. These circumstances, Mattel believed, undermined the Barbie brand and devalued her commercial value. They likened MCA Records to a bank robber, piggybacking on Barbie’s fame to sell their record.

They filed a lawsuit against MCA, with the record company then countersuing for defamation over the “bank robber” inference.

The two cashed - up corporate heavyweights, both in a fighting mood and flexing plenty of legal muscle, commenced to slug it out through the US Court system. After lengthy proceedings Mattel’s claim was dismissed but an appeal was then launched in the US Supreme Court. In 2002, Judge Alex Kozinsky, perhaps showing signs of exasperation, again dismissed Mattel’s suit together with MCA’s countersuit for defamation, and at the same time advised both groups to “chill out”.

The whole fabulously expensive legal battle then ground down into a sort of bloodstained draw, ending what surely must be the only time a toymaker has sued a record company.  This strange case is a unique example of the law working in mysterious ways.

Aqua’s famous video clip of “I’m a Barbie Girl” can be seen here.

And in a strange twist to the tale, the following clip is a television advertisement for Fashionista Barbie, presumably approved by Mattel. The jingle seems strangely reminiscent of Aqua’s original tune that precipitated all the legal drama! But somehow I don't think anyone will sue.

Wednesday, January 25, 2012

Weather and Health

It has long been recognised that the weather can affect our general mood and feelings of well-being. Cabin fever is a well-known psychological condition arising from an extended period of inclement weather that forces people to remain indoors. Symptoms include irritability, forgetfulness, excessive sleeping, and in extreme cases, paranoia.

Prolonged spells of hot weather are often associated with a spike in human mortality, particularly for the very young, the very old or the ill, and it is believed that so called heat waves are responsible for more human deaths than the more spectacular weather events such as hurricanes, tornados and gales. 

Washington citizens cool off in a fountain during the heat wave of 2010.
Image from Wikipedia Commons - click to enlarge

Increases in domestic violence also appear to cluster during hot spells, with irritability rising during these times. Increased consumption of alcohol may also be a factor here.

But it is also suspected that weather can influence our general health in a variety of other ways and this has proven a fascinating area of research since the mid nineteenth century.

An academic study was undertaken soon after the American Civil War by the eminent Philadelphian physician Dr. S. W. Mitchell who was interested in the effect of weather on war wounds and limb amputations. He observed that falling barometric pressure, together with rising temperature and humidity, frequently produced neuralgic pains in amputees.

Dr. Silas Weir Mitchell, c 1875
Image from Wikipedia Commons - click to enlarge

This observation was reinforced some 70 years later in an experiment performed by a German meteorologist Otto Hoflich. He correlated the pains experienced by a World War II soldier, Claus Thurkow, with the prevailing weather situation. Thurkow had lost his right arm during the War, and under instructions from Hoflich, kept a detailed diary on the dates and times when he experienced pain in the stump of his arm. The results were similar to Mitchell's conclusions regarding Civil War veterans.

It is believed that other conditions producing pain in the various joints of the human body, such as arthritis and gout, may also be weather sensitive, perhaps responding to changes in barometric pressure, temperature and humidity levels.

An acute case of rheumatoid arthritis
Image from Wikipedia Commons - click to enlarge

Perhaps the most surprising weather correlations that have been observed concern the beginning and cessation of life itself. Statistical correlations between the weather and coronary thrombosis (heart attack) have been demonstrated, usually involving conditions experienced with the approach of a cold front. Obviously weather is not the primary cause but perhaps the falling barometric pressure associated with an approaching cold front can trigger the onset of an attack in a person whose heart is critically poised because of disease.

Paradoxically, similar weather conditions appear to also precipitate the beginning of life with a statistically relevant correlation appearing between falling barometric pressure and the onset of spontaneous labour in childbirth. 

The onset of spontaneous labour in childbirth could be triggered by weather conditions.
Image from Wikipedia Commons - click to enlarge

Although the actual mechanisms involved in these situations are not understood, the statistics point to connections that demonstrate weather affects us in a whole variety of indirect ways. 

Perhaps in addition to the usual information, weather forecasts of the future will contain neuralgia advices, arthritis alerts and gynaecological warnings. 

The Australian Weather Book, Edition 3, Keith Colls and Dick Whitaker, New Holland, 2012

Weather, Climate and You, H. E. Landsberg, Weatherwise, Vol 39, Issue 5, 1986