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Friday, 31 October 2014

Curtiosity about ants and arachnids

Just a further reminder: the curtiosity entries represent selections from a book-sized file of quotes, garnered and stored against some future possible need for epigraphs and epigrams (and, yes, I am old enough to know the difference). They are more than a little random, because that's the nature of scrap books.

One difference from other collections of quotes on the interwebs: these ones are all as fully documented as I can manage.  I hate it when a quote lacks any provenance trail!

Many various kinds of ants inhabit New South Wales and Van Diemen's Land; I know about a dozen species myself. One is a very formidable-looking personage, full an inch long, with a shiny coat of mail gleaming purple and blue, and a threatening sting, which I am told inflicts a most painful wound, as severe as that of the hornet.
— Louise Ann (Mrs Charles) Meredith, Notes and Sketches of New South Wales. London: John Murray, 1844, and Ringwood: Penguin Books, 1973, page 69.

Ants are creatures of little strength, yet they store up their food in the summer.
— Holy Bible, Proverbs 30:25.

Go to the ant thou sluggard; consider her ways and be wise.
— Holy Bible, Proverbs, 6:6.
Moreover, it is commonly said, that a frog hath a double liver, which ought to be laid before ants; and look which of the two lobes or flaps thereof they make unto and seem to gnaw, the same is a most singular antidote against all poisons whatsoever . . .
Pliny, The Natural History, c. 80 AD.

There is no way of keeping ants out of a tent. Those called soldiers or riflemen are the worst. Bushrangers are alleged to have captured a policeman, then bound and thrown him on a soldier-ant nest, where he was stung to death.
C. Rudston Read, What I saw, heard and did at the Australian Gold Fields, 1853, pp 220-221.

Another type of snare is constructed by the 'ant-lion' larvae of certain Myrmeleontidae (Neuroptera). They excavate conical pits in dry, sandy places, by backing into the sand in a circular pattern and flicking off the material that falls on to their head and jaws, so that the sides come to lie at the angle of repose of the sand. Ants or other small insects that tumble into the pitfall are usually seized immediately by the ant-lion, which lies concealed in the sand at the bottom of the pit with its mouth-parts agape. However, if the victim attempts to escape up the sides of the pit, sand is flicked up and either dislodges it or causes the walls of the pit to slip beneath it. Vermilionine Rhagionidae (Diptera) have the same habit in the northern hemisphere, a remarkable example of convergent evolution.
— CSIRO, The Insects of Australia, Melbourne University Press, 1970, p. 129.

He that diggeth a pit shall fall into it.
— Holy Bible, Ecclesiastes, 10:8.

You can get to know your own forehead mites the following way: stretch the skin tight with one hand, carefully scrape a spatula or butter knife over the skin in the opposite direction, squeezing out traces of oily material from the sebum glands. (Avoid using too sharp an object, such as a glass edge or sharpened knife.)  Next scrape the extracted material off the spatula with a cover slip and lower the slip face down onto a drop of immersion oil previously placed on a glass slide. Then examine the material with an ordinary compound microscope. You will see the creatures that literally make your skin crawl.
— Edward O. Wilson, The Diversity of Life, Belknap 1992, 177.

My father chastised you with whips, but I will chastise you with scorpions
— Holy Bible, 1 Kings, 12:11.

Tis true, a scorpions oil is said
To cure the wounds the vermine made;
And weapons, drest with salves, restore
And heal the hurts they gave before;
—Samuel Butler, Hudibras, Part III, Canto II 1029–1032. (1662)

Mix equal quantities of oil of scorpions and oil of beeswax, and apply the warm mixture to the kidney.
—Robert Boyle, Medicinal Experiments: or, a collection of choice and safe remedies, 1696, vol II, p. 111.

…bruised and applied to the Place, they cure the Poison of their own Stings, others take it bruised in Wine, others instil Oil of Scorpions into the Wound. The Oil of Scorpions, is by some recommended as effectual in a Suppression of Urine, the Bladder being anointed with it hot, or before a Fire.
Pharmacopoeia Universalis, or, a New Universal English Dispensatory, 1747, 527–8.

Now for the spotted lizards called stellions, a scorpion stamped is singular good against their poisons . . .
—Pliny, The Natural History, c. 80 AD.

'Will you walk into my parlour?' said a spider to a fly
'Tis the prettiest little parlour that ever you did spy.
— Mary Howitt (1799-1888) The Spider and the Fly.

The insect I am now describing lived three years; every year it changed its skin, and got a new set of legs. I have sometimes plucked off a leg, which grew again in two or three days. At first it dreaded my approach to its web; but at last it became so familiar as to take a fly out of my hand, and upon my touching any part of the web, would immediately leave its hole, prepared either for defence or an attack.
— Oliver Goldsmith (1728 - 1774), 'The Philosopher and the Spider', in Animated Nature.

Amazonian tarantula, met a few months ago.
It is proven today that the tarantula is innocuous, as are almost all spiders in our country; but there is not a child, especially in the country, whose mother does not say: 'Don't touch it, it's a spider, it's poisonous'; and childhood memories are indelible.
— Primo Levi, 'The Fear of Spiders' in Other People's Trades, page 144.

Many people, children and adults, men and women, brave and fearful, are deeply repelled by spiders, and if they are asked why spiders in particular, they usually answer: 'Because they have eight legs.'
— Primo Levi, 'The Fear of Spiders' in Other People's Trades, page 141.

So why aren't people as frightened of two red setters, which have more fangs and longer and hairier legs, which can run faster, jump higher, and can surround you?
— Duncan Bain (pseud.) (1944 - ) 'Wring the toxin', from Carl Orff the Dogs, Anura Books, 1985.

Long before the Great Age of Dinosaurs, creatures of humbler build called arthropods began to leave the sea and adopt a life on the land. Not only were arthropods, which include all those animals with an external skeleton and joint ed limbs such as insects, ticks, scorpions and centipedes, the first animals to colonize the land but according to many zoologists they will also be the last survivors.
— Barbara York Main, Spiders, Collins, 1984, 13.

Something completely different: 
How far do ants roam from their nest?
This is lifted from the manuscript of my book Australian Backyard Naturalist, where there is lots more good stuff like this.  I'm not at all sure this made it into the book, but it's hard to get, now, so here it is for free.

About the only way to answer this is to mark some ants and follow them. A quick look at the scientific literature reveals that when scientists mark ants, they use a readily available pen, the 'Artline' 999XF in silver, which has a 0.8 mm "nib", which you can buy at any large stationery shop.

You need to get the pen working first, pressing it down hard on a piece of paper, and then you can mark a dozen ants just by touching each one gently on the abdomen (the tail portion). After that, you need to press the pen hard on paper again.

The ink stays on the ants, and does not seem to harm them. I managed to sight several marked ants on the day after my trial, so it obviously does not make the other ants attack them, something that can happen with some smelly ways of marking ants.

If you are studying ants that are likely to bite or sting, try standing with your feet in two dishes or buckets of water.

Monday, 27 October 2014

Charles Wilkes and the US Exploring Expedition

This one went to air in late 1989, close to the sesquicentenary of Wilkes' arrival in Sydney. Preparing for it involved reading, among other things, the facsimile of Wilkes' rather contentious 500+ page autobiography, never published in print, but reproduced as a facsimile. He was, shall we say, an interesting case.

It was a dark and moonless night, the night of November 29th, 1839, a hundred and fifty years ago last week. The place was the Heads, at the entrance to Sydney Harbour, and it was just after sunset. Unseen by the watchers on South Head, who were paid to notice such things, two alien warships slipped quietly into Port Jackson.

It wasn't really all that hard for them to sail in: Macquarie Light shone bravely out on South Head showing the way, and they had sailing directions and an accurate chart of the harbour, prepared by Phillip Parker King, about twenty years earlier.

Since that time, a new light had been placed on the only dangerous reef, the Sow and Pigs, but the chart and sailing directions were otherwise complete and accurate. In any case, there were scattered lights along the southern shore, to guide the ships as they sailed in. It wasn't really a great navigational feat, the way the foreign captain later claimed.

The two ships sailed quietly down the harbour to Sydney Cove and dropped anchor: the United States Exploring Expedition had started to reach Sydney. Next morning, according to the Americans, the whole town was shocked and horrified to discover that two foreign warships could approach in this way, all unseen, mind you, to a position where they might have destroyed Sydney, had they so wished.

So what were they doing here, these Americans? The Exploring Expedition, consisting of the two warships, and two other ships which followed a day or so afterwards, was on the way to explore the Antarctic, to go where no man had gone before, to discover new realms.

I suppose it was pretty inevitable that I'd one day turn to the study of Antarctic exploration. After all, Charles Laseron who wrote South With Mawson used to live in a house that backed on to ours, and my first science teacher, the man we called "Penguin" Watson, was another of those fabulous south-gangers.

And yet it was a completely different line of enquiry that brought me to the United States Exploring Expedition. You see, one of those who visited Sydney with the American fleet was James Dwight Dana, the man who gave us that classic of geology that we still know, even in its most recent editions, as Dana's Mineralogy.

But what was a geologist doing, sailing around the world in a flotilla of US naval craft, I wondered? I mean, sailors usually prefer to steer clear of rocks, don't they? You'd think the pickings for a ship-board geologist would be slim, limited to what you could dredge up from a great depth, or find stuck to the anchor.

Maybe, I thought, it was something to do with his distant relative, Richard Dana, who dropped out of legal studies to travel around Cape Horn, a trip that Richard later celebrated in the famous book Two Years Before the Mast.

But no, geologist James was on the maritime kick first, for he'd been a sea-borne tutor in mathematics to midshipmen in 1833, well before Richard's trip. In those days, midshipmen were sent to sea in training ships, and taught practical skills as they went. So off he sailed, off round the Mediterranean for sixteen months.

James Dana made the trip mainly so he could examine famous geological features in the breaks between his mathematics classes. Then, when that cruise was over, Dana returned to America as a junior assistant in a college, and just a few years after, published his System of Mineralogy at the ripe old age of 24, in 1837. The seventh edition of Dana's Mineralogy, by the way, was completed in 1962, so you can see that the book is something of a perennial.

And that was how the US Navy came to import this bright young man, already blooded in a sixteen-months cruise, when they headed off into the Pacific in 1838. There were going to be lots of rocks to be seen, and I suspect that there might just have been the odd Colonialist glint in the eyes of those who wrote Wilkes' orders in Washington.

The US authorities even admitted to grubby commercial considerations as the prime concern of the expedition, and if the Americans did have any colonial ambitions, it would be handy to have somebody along who could recognise valuable minerals when they turned up.

At that time, whale fishing alone accounted for ten per cent of all US ships on the seas, and the annual loss of ships on uncharted reefs and islands was about as much as the total anticipated cost of the expedition. But if that was all they had in mind, just the charting of new reefs and islands, there was no need of a geologist: a navigator was what they really wanted.

Charles Wilkes
And so we come to Wilkes, an expert navigator. Lieutenant Charles Wilkes, as he was then, though he was a Rear-Admiral before he died, and rather lucky as well.

Incredibly lucky, in fact. Exploring Polar seas is best done by experienced people in strong vessels: Charles Wilkes went into the howling Antarctic gales, totally inexperienced, in four veritable cockle-shells, and yet he came out with all his ships intact. The crew were scurvy-ridden, but he brought them back.

Then again, being court-martialled and found guilty is usually enough to ruin any naval officer's career. Wilkes was court-martialled twice, and found guilty twice, the second time for almost provoking war with England, and yet he still ended up Rear Admiral.

When I learned this, I decided that maybe Wilkes was an interesting character who ought to be further investigated. Well after all, he left his name on the Antarctic continent, in Wilkes' Land, didn't he? In the end, I was right and I was wrong.

A specialist in charts and navigation, Wilkes had sailed to England in 1836 to purchase books and instruments for the expedition. While there, he met with James Clark Ross, soon to command a British expedition to find the South Magnetic Pole, and their paths were to cross again, rather disastrously for Wilkes, in southern waters.

But back to Wilkes. After fitting out, he led his motley flotilla of six ships out to sea in August 1838. The largest was a 780 ton sloop, Vincennes, and the rest were all even smaller, down to a couple of hundred-ton tenders, Flying Fish and Sea Gull. By the time they reached Sydney in 1839, a stores ship had been sent back to America, and Sea Gull had been lost with all hands, so the fleetlet was down to four ships when they arrived in Sydney.

Many writers have been critical of the structural weakness and small size of Wilkes' ships, given that they were to sail in Antarctic waters. As a matter of fact, the people of Sydney were unimpressed by the fleet as suitable vessels for tackling the icy wastes, but this was only one of the Americans' aims, just a small part a four-year cruise around the Pacific, and around the world.

A little pilot boat like Flying Fish was ideal for surveying and charting in close to coral reefs. Yet while they were suited to exploring the ice-free waters further north, the vessels lacked sufficient strengthening, and they were poorly insulated.

In fairness, we should note that Wilkes had tried reinforced ships: in his autobiography, he records that the ships handled appallingly. On top of that, they couldn't carry enough gear, and so Wilkes was forced to accept something rather second-best, a compromise.

From a scientific view-point, his trip to the ice was most disappointing. All of the scientists were left behind in Sydney, ostensibly because they would be "worse than a useless appendage".

There may have been more than this, for whatever was found on the trip was to be kept a secret by the US government, and the scientists would have this urge to publish, wouldn't they? And what did the US government hope to find? Why, Symmes' Hole, of course! At least, I think that's what they were after. They denied it so often, they must have been looking for Symmes' Hole.

Symmes was an American military gentleman, who had a novel idea about the world's structure. It was hollow, he said. Those Magellanic clouds in the southern sky weren't really collections of stellar matter, way out in space: they were reflections of other worlds, inside the earth, accessible only by holes that opened out near the poles.

Symmes almost got congressional support to mount an expedition to find these holes in the 1820s, and the idea was still about in the late 1830s, though nobody of any sense believed the yarn. But if there was any hope in anybody's mind about finding Symmes' Hole in the Antarctic, it would make good sense to keep the whole business secret from the scientists, just in case you failed. Still, whatever the reason, Dana and the other scientists were all left behind in Sydney.

This enforced stay in Sydney gave Dana time to contemplate, to think things over. He'd already been studying coral islands, and had some glimmerings of an idea as to how they were formed.

While he was in Sydney, Dana read a short newspaper account of Charles Darwin's ideas: these were in accord with Dana's own ideas, and he was spurred on to gather even more information to support their joint theory.

Meanwhile, some distance to the south, Wilkes had found no holes leading into the interior, and no land either, apart from Adelie Land, discovered by Dumont D'urville, just seven days earlier.

At anchor in the Bay of Islands in New Zealand, Wilkes had dashed off a quick letter and a sketch map for his friend Ross, to save Ross time in his own search. As it happened, though, Ross was more interested in magnetic variations, and so he sailed over the same area. And where Wilkes recorded land at 65o40' South, 165o East, Ross could find no bottom with a six-hundred-fathom line. Wilkes' alleged coast-line was at least a kilometre under water!

Wilkes had been wrong. Either he'd misinterpreted cloud as land, which is easy to do, or he'd made an error in navigation. Whatever the cause, he was wrong. Ross tried to make this error known to Wilkes on the quiet. Sadly, Ross used an intermediary by the name of Aulick, another American naval officer who was in the Pacific, and who claimed to be a friend of Wilkes'. He wasn't.

Aulick took great pleasure in spreading the word far and wide around the Pacific that Wilkes had got it all wrong, that there was no land there at all, that the English had proved this. Aulick's pleasure may have been related to the fact that he had tried to talk Wilkes into giving up the command.

Wilkes lacked experience, he suggested. Quite obviously, Aulick felt that he would have been better choice, and Wilkes did not endear himself to the older man when he clicked his fingers under Aulick's nose before walking off. And so Aulick took his gleeful revenge on Wilkes.

This meant that Wilkes was not only denied his discovery of new land, he was made to look universally foolish, both in the Pacific, and back in America.

Ah, you may say though, what about Wilkes Land in Antarctica? He must have discovered that, surely? Well, I'll let Sir Douglas Mawson answer that question for us. After all, it was Sir Douglas who discovered what we now call Wilkes' Land.
To this country, which had never before been seen, was given the name of Wilkes's Land, to commemorate that great American Exploring Expedition.
Though Wilkes fixed such names as Knox Land, North's High Land etc., to coasts reported to have been seen by him, it has been left for us to commemorate his own name in like manner by attaching it to this new stretch of coast.

So in the end, what did Wilkes achieve? Well, the expedition collected much useful information, and many useful plants, all round the Pacific, ranging from close to Antarctica, all the way up to Japan, and he circumnavigated the world.

James Dana gained the time to mature his scientific thinking, and Dana, Louis Agassiz and Asa Gray all worked on the expedition's collections, describing and detailing them, and the abridged version of the report became a minor classic of the 19th century. Wilkes has also given rise to a rather interesting display at the Smithsonian Institution in Washington.

But Wilkes didn't find Symmes' Hole, he didn't discover new lands in Antarctic waters, and I don't think he really frightened the burghers of Sydney by rudely landing, unannounced, in their midst.

You see, I've read the local papers for the whole of the period of his visit, and hardly a reference to the expedition could I find, and certainly no breath of scandal about enemy warships sneaking in.

I suspect that tale was all the fabrication of a cranky old man, rather careless of the truth at the best of times, scrawling out his autobiography in his declining days. One thing is sure: Wilkes says he sailed ten miles up the harbour to anchor at Sydney Cove, and that's impossible.

Or at least I think it is. I live in Manly, and I'm currently checking the records to see if any strange keel marks were found, running down the Corso, late in 1839. For unless he sailed over dry land, there can be no way that he travelled ten miles down the harbour to Sydney Cove.

But it was a dark and moonless night: my colleague Nick Lomb at Sydney Observatory checked it for me in his tables -- they're rather good at that up at the Observatory -- and the moon rose rather late, around midnight. So that part of the story is indeed confirmed as true, unless of course Wilkes sailed in later than he told us: after all, nobody actually saw him, did they?

And something that Wilkes doesn't tell us, and maybe didn't even know himself, is equally true: Wilkes seems to have been, at least in part, the model on whom Herman Melville based his character, Captain Ahab. You know, Captain Ahab as in Moby Dick. And that's got to be better than frightening a few burghers of Sydney, surely?

Post scriptum: Some two months after this went to air, I read Anthony Trollope's account of his travels in Australia, (and in passing of the huge fortifications around Sydney Harbour). Trollope makes it very clear that the major worry for Sydney-siders around 1871 was the Americans. Look, the folk of Sydney said, at the Alabama case and the Trent case. The Trent case was the incident which led to Wilkes' second court-martial. So maybe Wilkes was telling the truth after all!

Sunday, 26 October 2014

In cahoots with the mahouts

Background: Have you ever wondered how leaders get to be the way they are? In more than one of my stints of teaching, I had to wonder VERY hard indeed — and educational institutions are much like elephants: large, lumbering and grey.

Having been both an educational leader and a management consultant by the 1990s, I had gone back to teaching because I enjoyed it — until we got a leader whom I dubbed Wackford Squeers.  The man was a complete idiot, but I dealt with him as I often deal with idiots, using gentle ridicule.

Well, maybe you won't think it gentle, but it was, when you compare it with the shock I gave him later — but that's another story.  I only show my nice side, most of the time, which is why he got such a shock. Anyhow, here is what I shared around:

There are four ways to lead an elephant.

You can walk beside the elephant, giving it guidance where necessary. The drawback is that occasionally, if you or the elephant don't take care, you may get pushed sideways into a thorn bush, but that is generally just a minor cost to pay for the benefit of having the elephant's services at your disposal. Mind you, it doesn't make you look all that important, because all you do is help the elephant find the best way to get the work done.

You can walk in front, playing the part of pointy end - and run the risk of being trampled by the pachydermatous following when some obstacle arises, and you get shoved against a wall, or worse, you risk being rammed into a thorn bush. People will see that you are in charge, they will notice how ragged you are getting (all those walls and thorn bushes), but they will certainly hear the noises you make.

You can sit on the elephant's head, pulling at its ears with a hook, guiding the elephant to go in the desired direction, occasionally talking to it, even. The elephant is free to belt you with its trunk, or scrape you off by walking under a low bough, but it knows you have the hook. Through no great effort, you have risen to a considerable height, for which achievement, most elephant drivers will take full credit, and people can most certainly see that you are in charge.

For risk-free leadership, you can walk behind the elephant with a slingshot and a pocket full of pebbles, administering shocks to the rear to guide the elephant back onto the right path when it strays. This is fun, because the elephant has no idea where it is supposed to go until you offer your bolt-from-the-blue guidance directive when the elephant goes the wrong way.

Analogous forms include the electric cattle-prod form of leadership and the boot up the fundament form of leadership. The problem here arises from which business end of the elephant you are standing near, and the risk that your guidance bolts may cause unwished-for sphincter activity.

Now excuse me, I have to get on, as I keep feeling these sudden sharp pains in my nether fetlocks.

Monday, 20 October 2014

Crooked Mick and the drop bears

I've been busy, finishing a book that I will talk about here later, though my facebook friends know all about it, and are probably getting heartily sick of it.  Anyhow, here's something I prepared earlier...

* * * * * * * * * * * * * * * * * * * * * * * * * *

There was one serious problem, back before the big flood, and that was the drop bears in the Speewah Ironbarks.  Now if you want to be really fussy, of course, they aren't bears at all, but a form of koala with a carnivorous habit.

Like the koalas, the drop bears are marsupials, with the same sort of pouch.  Funny thing is that the koalas and the drop bears both have a pouch that faces backwards.  The scientists say this is because they evolved from a sort of burrowing animal just like the wombat, which also has a backward-facing pouch.

I reckon Mick would've got the Sydney Harbour tunnel done easier if he'd used a couple of drop bears, if they can burrow, because their claws can rip into a Speewah Ironbark and slice through steel, but there's no reasoning with one of them—and even less chance of reasoning with two of them.

Back to the pouches though, a pouch like that makes sense in a wombat, because it digs burrows in the ground, but it seems just a bit odd in an animal that mostly lives in trees.  Anyhow, that's how the koala and the drop bear are, though the scientists at the museum are still arguing about whether the drop bear is more like a koala or a wombat.  Still, just goes to show that nature is sometimes a bit dumb.

The drop-bears are even dumber, when you come to it, and that was how Crooked Mick managed to get the problem under control, around the Speewah homestead area.  You see, ordinary drop-bears are usually only able to prey on small marsupials, things up to the size of an ordinary rabbit, but everything on the Speewah is big, including the rabbits and the drop-bears.

Some of them, from time to time, have been known to attack humans, using the same method that they use on small animals, even in the suburbs of the towns and cities along the east coast.  That is, they drop from a great height, and sink their razor-sharp canine teeth into the victim's throat, slashing the jugular vein, then they leap to one side, and wait for the victim to fall over.  As a matter of fact, I saw one try it in the Sydney Domain, round the back of Parliament House, one time, but it attacked a politician, and they're all bloodless anyhow.

Usually, the bears drink the victim's blood, but some of the more daring drop-bears on the Speewah had developed a taste for human flesh.  There are no two ways about it. They were man-eaters, though they seemed to prefer being woman-eaters and child-eaters, so people were pretty cranky about that.  We didn't mind too much when they just knocked off an overseer or two, but when they had a go at one of the shearers, we got good and cranky, I can tell you.

Anyhow, Crooked Mick knew a thing or two, and he knew how the original inhabitants of the area had solved the problem of drop-bears.  Walk through the area with two spears held vertically, one against each ear, and going well above the head, and make a sort of drop-bear kebab: that was how the Koori people used to deal with the problem.  In good times, Mick had been told, one stroll through a drop-bear grove, and you had a feast for the whole tribe, all neatly skewered on two spears.

Mick's first attempt was with a couple of crowbars, sharpened with a good stone, and that nearly did for him.  You see, he hadn't scaled up to a proper Speewah size.  The first two drop-bears on each side filled the crowbars up, and the ones that rained down after that bounced off their cousins on the crowbar, landed softly, and came in at Mick, spitting and snarling.

Luckily, Crooked Mick doesn't panic.  Nobody on the Speewah panics, but if anybody was ever going to, this would be the time.  There must have been a hundred of the things coming at him from all sides, crazed for blood: we were half a mile away, watching from out in the open, and we could hear the noise from there.

Anyhow, Mick stayed calm, and waving the two crowbars around, he flung off the four impaled drop-bears, which flew over our heads and off into the distance, and then ran straight at the live drop-bears, roaring and using the crowbars as two clubs.

Instead of stabbing, with the risk of getting the crowbars caught in the tough hides of the animals, he went through methodically, smashing the canines of each animal as it came within reach, rendering them harmless.  A few of them, disarmed in this way, retreated to the trees, but they were soon replaced by more drop-bears, drawn in by the noise and the smell.

Meanwhile, the boss and three of his mates had ridden up with rifles, and they opened up on the injured drop-bears on the ground.  They were good shots, so every now and then they dropped a bullet down the throat of a snarling animal and killed it, but most of the bullets just bounced off their hides.

That made it hard shooting for them, because they had to make sure a stray ricochet didn't get Crooked Mick.  Still, Mick was wearing a Speewah kangaroo skin vest and trousers, so he was about as safe as a knight in armour, from all but a really unlucky shot.

Anyhow, in the end, the drop-bears withdrew, still snarling.  There must have been four hundred dead ones, littered across the ground as we moved in with carbide-tipped chainsaws to skin them, and twice as many again, up in the trees.  We kept a good eye on them as we skinned the dead ones, I can tell you, but they seemed to have had enough for one day.

That night, Crooked Mick was busy in the smithy, clanging and banging away.  The Professor, who knew about these things, said it reminded him of Siegfried, who was a German bloke who killed drop-bears and things in some opera.  At least, I think that's what he said.  Anyhow, by daybreak, Mick had these two wicked-looking skewers, at least ten times his height, opening out into a broad sort of sword blade, which was as sharp as his axe, then flaring into a shield below that.

The boss came down about then, so Mick explained that the idea was to have the drop-bears impale themselves, slide down and be slice open on the sword part, and then be thrown to one side by the shield part.  The boss reckoned a few of the drop-bears would only be lightly wounded, but Mick pointed out that the wounds would make good targets for the riflemen, and give the bullets a way in.

Well, it worked a dream.  Mick went into the drop-bear groves, one by one, got nearly all of them with his bear-sticker, and the boss and his mates did for the wounded ones.  There were a few drop-bears left, the young ones which had not acquired a taste for human blood.  As Mick pointed out, it was only the ones which attacked him that died that day.

We were able to leave the groves further out alone, where the drop-bears weren't killers, and later, Mick even trapped a few adults and brought them in to ensure the survival of the species in the area, by providing a balanced population.  Like I say, he's a real softy, at heart.  Smart, but.

* * * * *

Note: there is a whole book of these stories, which I am currently pitching to publishers, but they will probably appear in an e-book.

There will be quite a number of these on the blog, all with the tags Speewah and Crooked Mick.

Tuesday, 14 October 2014

Curtiosity about animal behaviour

And anatomy...

There be three things which are too wonderful for me, yea, four which I know not: the way of an eagle in the air; the way of a serpent upon a rock . . .
— Holy Bible, Proverbs, 30:18-19

Animals studied by Americans rush about frantically, with an incredible display of bustle and pep, and at last achieve the desired result by chance. Animals studied by Germans sit still and think, and at last evolve the solution out of their inner consciousness.
— Bertrand Russell (1872 - 1970

A curious case has been given by Prof. Möbius, of a pike, separated by a plate of glass from an adjoining aquarium stocked with fish, and who often dashed himself with such violence against the glass in trying to catch the other fishes, that he was sometimes completely stunned. The pike went on thus for three months, but at last learned caution, and ceased to do so. The plate of glass was then removed, but the pike would not attack these particular fishes, though he would devour others which were afterwards introduced; so strongly was the idea of a violent shock associated in his feeble mind with the attempt on his former neighbours.
— Charles Darwin, The Descent of Man, second edition, John Murray, 1885.

The writer found that certain freshwater crustaceans, namely Californian species of Daphnia, copepods, and Gammarus when indifferent to light can be made intensely positively heliotropic by adding some acid to the fresh water, especially the weak acid CO2. When carbonated water (or beer) to the extent of about 5 c.c. or 10 c.c. is slowly and carefully added to 50 c.c. of fresh water containing these Daphnia, the animals will become intensely positive and will collect in a dense cluster on the window side of the dish. Stronger acids act in the same way but the animals are likely to die quickly. . . Alcohols act in the same way. In the case of Gammarus the positive heliotropism lasts only a few seconds, while in Daphnia it lasts from 10 to 50 minutes and can be renewed by the further careful addition of some CO2.
— Jacques Loeb (1859 - 1924), Forced Movements, Tropisms, & Animal Conduct, Dover edition of 1973, pp. 113 - 114.

Every family has a skeleton in the cupboard.
— Proverb

If I were a Queensland giant
With great big smelly feet,
I'd stomp on a Queensland cane-toad
And make my feet smell sweet.
— Duncan Bain (pseud.) (1944 - ) 'Cane toed', from Tad to Telegraph: a history of the Poles, Anura Books, 1983.

Social chaos is hell for the family and for those who have destroyed the family as well.
Bhagavad Gita, 1:43, in the translation of Eknath Easwaran, Arkana Books, 1985.

Rembrandt van Rijn The Anatomy Lesson of Dr Tulp
If anyone wishes to observe the works of Nature, he should put his trust not in books on anatomy but in his own eyes and either come to me, or consult one of my associates, or alone by himself, industriously practise exercises in dissection; but so long as he only reads, he will be more likely to believe all the earlier anatomists, because there are so many of them.
— Galen, quoted in Boorstin, The Discoverers, 346

I went out to Charing Cross, to see Major-general Harrison hanged, drawn, and quartered; which was done there, he looking as cheerful as any man could do in that condition.
— Samuel Pepys (1633 - 1703), Diary (13 Oct, 1660),

Many right skilful masters in chirurgery, and the best learned anatomists, are of the opinion that the veins of the eyes reach to the brain. For mine own part, I would rather think that they pass into the stomach. This is certain, I never knew a man's eye plucked out of his head, but he fell to vomiting upon it, and the stomach cast up all within it.
— Gaius Plinius Secundus (23-79) The Natural History, translated by Philemon Holland, page 132.

The animal machine is governed by three main regulators: respiration, which consumes oxygen and carbon and provides heating power; perspiration, which increases or decreases according to whether a great deal of heat has to be transported or not; and finally digestion, which restores to the blood what it loses in breathing and perspiration.
— Antoine Laurent Lavoisier (1743 - 1794), Traité de Chimie (1793).

Sweet is the lore which nature brings;
Our meddling intellect
Misshapes the beauteous form of things;
We murder to dissect.
— William Wordsworth (1770 - 1850), 'The Tables Turned'.
If we view a Porpess on the outside, there is nothing more than a Fish, but if we look within, there is nothing less.
— Anatomist Edward Tyson, 1680

The Bat and the Weasels 

A Bat who fell upon the ground and was caught by a Weasel pleaded to be spared his life. The Weasel refused, saying that he was by nature the enemy of all birds. The Bat assured him that he was not a bird, but a mouse, and thus was set free. Shortly afterwards the Bat again fell to the ground and was caught by another Weasel, whom he likewise entreated not to eat him. The Weasel said that he had a special hostility to mice. The Bat assured him that he was not a mouse, but a bird, and thus a second time escaped.
It is wise to turn circumstances to good account.
— Aesop, Fables.

To such a person my hope has been that my treatise would prove of the very greatest assistance. Still, such people may be expected to be quite few in number, while, as for the others, this book will be as superfluous to them as a tale told to an ass.
— Galen, On the natural faculties.

Legend also says that while he is supposed to have learned anatomy in Paris under the great master of his age, Sylvius, an apocryphal tale has it that Vesalius was heard to remark that the only time he ever saw Sylvius use a knife was to eat his peas. But that remains legend: what we know for a fact is that after Vesalius was done with his work, anatomy had to be a science of observation.

Philosophy, astronomy, and politics were marked at zero, I remember. Botany variable, geology profound as regards the mud stains from any region within fifty miles of town, chemistry eccentric, anatomy unsystematic, sensational literature and crime records unique, violin player, boxer, swordsman, lawyer, and self-poisoner by cocaine and tobacco.
— Dr Watson describes Holmes in The Five Orange Pips.

Geology is related to almost all the physical sciences, as history is to the moral. A historian should, if possible, be at once profoundly acquainted with ethics, politics, jurisprudence, the military art, theology; in a word with all branches of knowledge by which any insight into human affairs, or into the moral and intellectual nature of man, can be obtained. It would be no less desirable that a geologist should be well-versed in chemistry, natural philosophy, mineralogy, zoology, comparative anatomy, botany; in short, in every science relating to organic and inorganic nature.
— Sir Charles Lyell (1797 - 1875), quoted in A Thousand and One Gems of English Prose, selected by Charles Mackay, (19th century?).

Friday, 10 October 2014

Curtiosity about (scientific) education

Another collection if unused epigraphs and pithy comments from past times.

My schoolmaster had been a little too crude in his instructions. He had not been a scientific man, but only a teacher of science.
— H. G. (Herbert George) Wells (1866 - 1946), The Work, Wealth and Happiness of Mankind, Heinemann, 1932.

As a schoolboy in London I learnt how sulphuric acid is manufactured, how time is measured at Greenwich, how soap is made, and how glass is blown — entirely from the teacher or the book, although all of these could have been seen at first hand within half an hour of the school. Adam saw the animals in the garden before he named them, but we (as Whitehead has said) named them before we saw them.
— Professor Eric Ashby, The Place of Biology in Australian Education, inaugural lecture, Sydney, 1939.

The true aim of the teacher must be to impart an appreciation of method and not a knowledge of facts. This is far more readily achieved by concentrating the student's attention on a small range of phenomena, than by leading him in a rapid and superficial survey over wide fields of knowledge. Personally, I have no recollection of at least 90 per cent of the facts that were taught to me at school, but the notions of method which I derived from my instructor in Greek grammar (the contents of which I have long since forgotten) remain in my mind as the really valuable part of my school equipment for life.
— Karl Pearson (1857 - 1936), The Grammar of Science, Everyman edition, p. 12n.

I find not any science that doth fitly or properly pertain to the imagination.
— Francis Bacon (1561 - 1626), Of the Advancement of Learning, second book, XI, 3, 1605..

In the circle where I was raised, I knew of no one knowledgeable in the visual arts, no one who regularly attended musical performances, and only two adults other than my teachers who spoke without embarrassment of poetry and literature — both of these being women. As far as I can recall, I never heard a man refer to a good or a great book. I knew no one who had mastered, or even studied, another language from choice. And our articulate, conscious life proceeded without acknowledgement of the preceding civilisations which had produced it.
— Shirley Hazzard, Coming of Age in Australia, Boyer Lectures, 1984, ABC Books, 1985.

In every respect but one, in fact, the old Mathematical Tripos seemed perfect. The one exception, however, appeared to some to be rather important. It was simply — so the young creative mathematicians, such as Hardy and Littlewood kept saying — that the training had no intellectual merit at all. They went a little further, and said that the Tripos had killed serious mathematics in England stone dead for a hundred years. Well, even in academic controversy, that took some skirting around, and they got their way.
— C. P. Snow (1905 - 1980), The Two Cultures and the Scientific Revolution, Rede Lecture, 1959.

T H Huxley, British Museum of
Natural History

Again, there is a fallacy about Examiners. It is commonly supposed that any one who knows a subject is competent to teach it; and no one seems to doubt that any one who knows a subject is competent to examine in it. I believe both these opinions to be serious mistakes . . . Examination is an Art, and a difficult one, which has to be learned like all other arts.
— Thomas Henry Huxley (1825 - 1895), 'Universities: Actual and Ideal', 1874, quoted in Cyril Bibby (ed.) The Essence of T. H. Huxley, Macmillan, 1967, p. 225.

Its so-called equipment is dirty and disorderly beyond description. Its outfit in anatomy consists of a small box of bones and the dried-up, filthy fragments of a single cadaver. A cold and rusty incubator, a single microscope, . . . and no access to the County Hospital. The school is a disgrace to the state whose laws permit it to exist.
— Abraham Flexner (1866 - ??), Medical Education in the United States and Canada (1910), page 190, quoted in Blaine Worthen and James Sanders, 'Educational Evaluation', New York: Longman, 1987, page 101.

My friend Tom Smith and I made it a rule - and in this we were encouraged by his father - that, so far as was possible, we ourselves should actually make the acids and other substances used in our experiments. We were not to buy them ready made, as this would have taken the zest out of our enjoyment. We should have lost the pleasure and instruction of producing them by aid of our own wits and energies. To encounter and overcome a difficulty is the most interesting of all things. Hence, though often baffled, we eventually produced perfect specimens of nitrous, nitric, and muriatic acids. We distilled alcohol from duly fermented sugar and water, and rectified the resultant spirit from fusel oil by passing the alcoholic vapour through animal charcoal before it entered the worm of the still. We converted part of the alcohol into sulphuric ether. We produced phosphorus from bones, and elaborated many of the mysteries of chemistry.

The amount of practical information which we obtained by this system of making our own chemical agents was such as to reward us, in many respects, for the labour we underwent. To outsiders it might appear a very troublesome and roundabout way of getting at the finally desired result. But I feel certain that there is no better method of rooting chemical or any other instruction, deeply in our minds. Indeed, I regret that the same system is not pursued by young men of the present day. They are seldom, if ever, called upon to exert their own wits and industry to obtain the requisites for their instruction. A great deal is now said about "technical education"; but how little there is of technical handiness or head work! Everything is bought ready made to their hands; and hence there is no call for individual ingenuity.

— James Nasmyth, James Nasmyth: Engineer, An Autobiography, 1883.

 The true aim of the teacher must be to impart an appreciation of method and not a knowledge of facts. This is far more readily achieved by concentrating the student's attention on a small range of phenomena, than by leading him in a rapid and superficial survey over wide fields of knowledge. Personally, I have no recollection of at least 90 per cent of the facts that were taught to me at school, but the notions of method which I derived from my instructor in Greek grammar (the contents of which I have long since forgotten) remain in my mind as the really valuable part of my school equipment for life.

— Karl Pearson, The Grammar of Science.

Mrs. Sanger's pamphlet on birth control, which is addressed to working women, was declared obscene on the ground that working women could understand it. Dr. Marie Stopes' books, on the other hand, are not illegal, because their language can only be understood by persons with a certain amount of education. The consequence is that, while it is permissible to teach birth control to the well-to do, it is criminate to teach it to wage-earners and their wives. I commend this fact to the notice of the Eugenic Society, which is perpetually bewailing the fact that wage-earners breed faster than middle-class people, while carefully abstaining from any attempt to change the state of the law which is the cause of this fact.

— Bertrand Russell, Marriage and Morals.

Sunday, 5 October 2014

Can you trust statistics?

This was a set of two talks, recorded somewhere around 1991 -- it ended up gaining a 'highly commended' in the Michael Daley awards.

As this speaks of health matters, John Snow's pump in Broad Street gains a few mentions in my talks, because it is my favourite example for lots of reasons.

I found where Broad Street used to be when I was in London -- though the Soho people I asked, mentioning a cholera outbreak were horrified, stating vehemently but in a low and urgent voice that there had never been cholera there, while looking around furtively, to make sure no tourists were in earshot.

Just around the corner, I found a replica of the pump, a plaque on which the name of a parochial politician was in larger print than Snow's, and also the John Snow pub. I went in and drank a beer to the great man (Snow, NOT the Councillor) , and bought a souvenir t-shirt. Now read on . . .

* * * * *

I'm a reformed smoker. I gave up many years ago, but I did it for political reasons. I just wasn't prepared to support the government of the day by paying tax on both liquor and tobacco, so I gave up the demon weed. Soon after that, the government changed, but I didn't like the other mob very much either, so I kept on not smoking.

Now it goes without saying that reformed smokers are tiresome people. At least if you're a smoker they are. They will keep on at you, trying to get you to stop as well, so they can hang another scalp on their thoroughly smug and sanctimonious belts.

To all non-smokers, those who still puff smoke are tiresome people, who can't see the carcinoma for the smoke clouds. Stupid fools who deny any possibility of any link between smoking and anything.

Like the tobacco pushers, the smokers dismiss the figures contemptuously as "only statistics". The really tiresome smoker will even say a few unkind things about the statisticians who stand behind the figures. Or about the statisticians who lie behind the figures.

But the smokers don't just settle for simple attacks, like alleging the statisticians are secret non-smokers. It's all very much nastier than that. So much nastier, there must be a deeply ingrained cultural hatred of statisticians in our society, and probably an equal contempt or detestation for statistics as well.

At one stage in my infamous career, I freely confess to having quite a lot to do with gathering statistics, and messing about with numbers, an honourable and harmless activity, I would have thought. But it was then I discovered that such people, while sometimes accused gently of being "mathematicians", more often suffer the far heavier opprobrium of being called "statisticians".

I certainly encountered this all-too-human tendency, and all too often at that. The things people used to say about statistics and the users of statistics offended me greatly.

If you've never suffered from being called a statistician, you may think it's a minor inconvenience to suffer. That's only because you've never heard the jokes which go with the label: there are more jokes about statistics than I know about the dismal science of economics, even if you let me throw in all of the many jokes I know about the economists as well.

Take, for example, the definition of a statistician as "somebody who's rather good around figures, but who lacks the personality to be an accountant". Or the story about the statistician who drowned in a lake with an average depth of six inches.

These days of course, we really ought to say fifteen centimetres, rather than six inches, but I'd like to stress the hoary agedness of so many of these witticisms about statistics: my reasons will become clear soon enough.

Then there are other clever-clogses who earnestly assure and advise us that a statistician collects data and draws confusions. We are also told statisticians are people who draw mathematically precise lines from an unwarranted assumption to a foregone conclusion.

With this sort of bias floating around, it's little wonder the great physicist, Lord Rutherford, once harumphed, "If your experiment needs statistics, then you ought to have done a better experiment".

Then there was the cruel and cutting comment, attributed to various witty people, and said to be about various people, that "X uses statistics much as a drunkard uses a lamp-post: rather more for support than for illumination".

On a slightly different tack, but still a debunking one, people will sometimes assert that statistics show how the vast majority of people have more than the average number of legs. Which is a bit like the common discovery, popular with conservatives, that tests reveal half our nation's school leavers to be below average.

Or the mildly sexist one-liner that statistics are like bikinis: what they reveal is interesting, but what they conceal is vital. And politicians like to get into the act as well, so we find Fiorello La Guardia, one-time mayor of New York saying statistics are like psychiatrists -- alienists he calls them -- statistics are like psychiatrists because they'll testify for either side.

Finally, there's the grand-daddy of them all, the famous line about "Lies, damned lies, and statistics". Now quickly answer out loud, so there's no cheating: who was it who first said that?

The odds are if there are two or three know-alls in your house, you'll now be locked in bitter dispute. At least, I hope you are. It may be hard on you, but it will help me prove my point.

The official version is that this line was first voiced by Mr. Disraeli, the well-known politician, but many quite reputable and reliable reference books attribute it to no less a personage than the author Mark Twain.

Now you can see why I expect to have started a few arguments by asking you to say your answers out loud. Even the experts can't agree on who it was said it! So if the authorities can't answer with one clear voice, how could you and your neighbours?

Well, the true facts of the case are fairly simple. That catchy snippet about "Lies, Damned Lies" et cetera was first published by Mark Twain all right, this can be proven to anybody's satisfaction, but Twain attributed the line to Disraeli.

The only problem is this: search as hard as you like, you won't find the story in any earlier publication than Twain's "Autobiography". In short, Mark Twain made the whole thing up! Disraeli never spoke those words: Twain invented them all, but he wanted the joke to have a greater force, and so gave the credit to an English politician.

Twain wasn't only well-known for his admiration of a good "Stretcher" (of the truth, that is), he even lied when he was talking about lies, and his name wasn't even Mark Twain, but Samuel Clemens! Now would you buy a used statistic from this man?

Come to think of it, the yarn's pedigree should have been enough in itself to cast doubt on the its veracity, with an arch-liar like Twain quoting, of all things, a politician! Yes, sad but true, there are more jokes about politicians than there are about statisticians, but only by a short head. It must be because so many politicians are trained originally as economists.

When you look to the background of the "Damned Lies" story as I did recently, there's an even stronger link between statistics and politics. Last century, when Disraeli is supposed to have made the remark, statistics were just numbers about the State. The state of the State, all summed up in a few simple numbers, as it were.

Now governments being what they are, or were, there was more than a slight tendency in the nineteenth century to twist things just a little, to bend the figures a bit, to bump up the birth rate, or smooth out the death rate, to fudge here, to massage there, to adjust for the number you first thought of, to add a small conjecture or maybe to slip in the odd hypothetical inference.

It was all too easy to tell a few small extravagances about one's armaments capacity, or to spread the occasional minor numerical inexactitude about whatever it was rival nations wanted to know about, and people did just that.

By the end of the last century, though, statistics were no longer the mere playthings of statesmen, and we find Francis Galton explaining that the object of statistics " to discover methods of condensing information concerning large groups of allied facts into brief and compendious expressions suitable for discussion".

So while you can go on sniping or objecting about being reduced to a mere statistic, those poor old statistics are still doing a fine job.

It's a pity, though, they've such a bad image problem, especially if you're trying to convert a diehard smoker from his or her evil ways.

As somebody once observed, or should have done if they didn't, figures don't lie, it's just that liars can figure. Presumably we don't set out to deceive ourselves deliberately: but could we use statistical information in such a way as to be unintentionally misled? I think it's very possible. Like fire, statistics make a good servant, but a bad master.

From Galton's time on, his meaning of statistics as some sort of numerical summary has become generally accepted, and the addition of "tests of significance" has added hugely to the number of statistics we can use.

So if the word "statistics" no longer means what it did when Mr. Disraeli didn't really make his comment, then it hardly seems fair to keep on giving statistics such a cruel and unusual treatment.

But as I implied before, I won't rush to the defence of your average number-abuser. If somebody does a Little Jack Horner with a pie that's absolutely bristling with statistical thingummies and they produce just one statistical plum, I won't be impressed at all: the plum's rather more likely to be a lemon, anyhow.

There are several handy little tests I apply to any figures and statistics which come my way: either the figures pass or they fail. These tests let me decide whether I'll take any notice of the figures or not. Statistical tests are very useful, especially if somebody is trying to prove by statistics that X causes Y.

In the first place, I want to know if there is a plausible reason why X might cause Y. If there isn't, then it's all very interesting, and I'll keep a look-out, just in case a plausible reason pops up later, but I won't rush to any conclusion. Not just yet, I won't.

Secondly, I want to know how likely it is that the result could have been obtained by chance. After all, if somebody claims to be able to tell butter from margarine, you wouldn't be too convinced by a single successful demonstration, would you?

Well, perhaps you would: certain advertising agencies think so, anyway. So let's take another tack: if you tossed a coin five times, you wouldn't think it very significant if you got three heads and two tails. Not unless you were using a double-headed coin, maybe.

If somebody guessed right three, or even four, times out of five, on a fifty-fifty bet, you might still want more proof. You should, you know, for there's a fair probability it was still just a fluke, a higher probability than most people realise. There's just about one chance in six of correctly guessing four out of five fifty-fifty events.

Now back to the butter/margarine dichotomy. Getting one right out of one is a fifty-fifty chance, while getting two right out of two is a twenty five per cent chance, still a bit too easy, maybe. So you ought to say "No, that's still not enough. I want to see you do it again!".

Statistical tests work in much the same way. They keep on asking for more proof until there's less than one chance in twenty of any result being just a chance fluctuation. The thing to remember is this: if you toss a coin often enough, sooner or later you'll get a run of five of a kind, and much more often than you'll fill an inside straight at poker.

As a group, scientists have agreed to be impressed by anything rarer than a one in twenty chance, quite impressed by something better than one in a hundred, and generally they're over the moon about anything which gets up to the one in a thousand level. That's really strong medicine when you get something that significant.

There. Did you spot the wool being pulled down over your eyes, did you notice how the speed of the word deceives the eye, the ear, the brain and various other senses? Did you feel the deceptive stiletto, slipping between your ribs? We test statistics to see how "significant" they are, and now, hey presto, I'm asserting that they really are significant. A bit of semantic jiggery-pokery, in fact.

And that's almost as bad as the sort of skullduggery people get up to when they're bad-mouthing statistics. Even though something may be statistically significant, it's a long way away from the thing really being scientifically significant, or significant as a cause, or significant as anything else, for that matter.

As I said earlier, statistics make good servants but bad masters. We need to keep them in their places. But we oughtn't to refuse to use statistics, for they can serve us well.

Some little time ago, I talked about Dr. John Snow, the man who solved a cholera epidemic in London in 1853. He did it by having the handle taken off a pump in Broad Street which was supplying polluted water. The story interested me, and I ended up researching it rather more deeply than I needed to, and I learned about some interesting side issues. Let me share one of them with you now.

During that same cholera epidemic in 1853, not ten minutes' walk from the Broad Street pump, in London's Middlesex Hospital, an unknown woman of thirty-three was helping to look after some of Snow's patients, and many other victims of the epidemic as well. It offered her some relief from the tedium of middle-class Victorian era spinster life, but her decision was a world-shaking one, nonetheless.

To us, she's no mere unknown, for that quiet spinster was Florence Nightingale. And while most people know her as the woman who founded the modern profession of nursing, there are just a few of us who know of her other claim to fame: as a founder of the art and science of statistics.

I'll come back to her in my next talk, and to whether the ABC is secretly driving you insane, and why all the podiatrists in New South Wales seem to be turning into public telephone boxes in South Australia. Or why I think that's what is happening.

My grandmother was one Florence Evans. Not an unusual name, they told me, lots of Evanses in Wales they said, so when I visited her native village of Manorbier, there was some doubt as to just which of several Florence Evanses I was talking about.

Still, after old Mrs Ogmore-Pritchard had eliminated the one who died at seventeen, and the one who died an old maid, she recalled the one who emigrated to wild colonial parts, and that was my Flo Evans.  From there, we found surviving relatives and said g'day.

Anyhow, Florence is a common enough name these days, but in 1820, it wasn't at all common. Only Florence Nightingale carried the name back then, and that was because she was born in the city of Florence, in a room with, by the sounds of it, a truly marvellous view.

It was only later, when Miss Nightingale became world-famous as the founder of modern nursing, that other young girls were also named Florence, in honour of the Lady with the Lamp. Aside, that is, from Percy Florence Shelley, the son of the poet, who was also born in Firenze. But for Ms Nightingale, the name might have remained non-gender-specific.

And yet, Florence the First, Florence Nightingale, could quite easily have turned into a fairly good mathematician: anybody with the steely resolve to break into nursing as it was in those days, when it was peopled by drunks and retired prostitutes, anybody game enough to take on all of that, could have done just about anything at all.

And certainly Florence had the interest in mathematics, and she had the ability. Unfortunately, she bowed to her father's wishes, and abandoned her interests. Or did she? After her name was made famous in the Crimea, Florence Nightingale returned to London in 1857, and started to look at statistics, and the way they were used.

First, she prepared a pamphlet, based on the report of a Royal Commission, studying the Crimean campaign. This little work, named "Mortality in the British Army", is generally believed to feature the first-ever use of pictorial charts to present statistical facts. Graphs, in fact, the origin of all those rinky-dinky little diagrams, beloved of geography teachers, you know the ones, with wheat bags, or oil barrels or human figures lined up like little paper dolls, or skittles, or whatever.

In the following year, 1858, Miss Nightingale was elected to the newly formed Statistical Society, just as she turned her attention to hospital statistics on disease and mortality.

In essence, she said, you could never discover trends in the data if everybody went happily around, concocting their own special data in their own sweet ways. You had to make everybody keep their figures in the same way. And so she prepared her scheme, published in 1859, for uniform hospital statistics. Her aim? No less than to compare the mortality figures for each disease in different hospitals, a thing which just could not be done under the old methods.

As in other spheres, Florence Nightingale was a success here, too, so the Statistical Congress of 1860 had, as its principal topic, her scheme for uniform hospital statistics.

These days, we use rather more sophisticated methods. It won't be sufficient just to say Hospital X loses more patients than Hospital Y does, so therefore Hospital X is doing the wrong thing. We need to look at the patients at the two hospitals, and make allowances for other possible causes. We have to study the things, the variables, which change together.

Earlier, I suggested that statistics are best regarded as convenient ways of wrapping a large amount of information up into a small volume. A sort of short-hand condensation of an unwieldy mess of bits and pieces.

And one of the handiest of these short-hand describers is the correlation coefficient, a measure of how two variables change at the same time, the one with the other.

Now here I'll have to get technical for a moment. You can calculate a correlation coefficient for any two variables, things like number of cigarettes smoked, and probability of getting cancer. The correlation coefficient is a simple number which can suggest how closely related two sets of measurements really are.

It works like this: if the variables match perfectly, rising and falling in perfect step, the correlation coefficient comes in with a value of one. But if there's a perfect mismatch, where the more you smoke, the smaller your chance of surviving, then you get a value of minus one.

With no match at all, no relationship, you get a value somewhere around zero. But consider this: if you have a whole lot of tennis balls bouncing around together, quite randomly, some of them will move together, just by chance. No cause, nothing in it at all, just a chance matching up. And random variables can match up in the same way, just by chance. And sometimes, that matching-up may have no meaning at all.

So this is why we have tests of significance. We calculate the probability of getting a given correlation by chance, and we only accept the fairly improbable values, the ones that are unlikely to be caused by mere chance.

The trouble is, all sorts of improbable things do happen by chance. Winning the lottery is improbable, although the lotteries people won't like me saying that. But though it's highly improbable, it happens every day, to somebody. With enough tries, even the most improbable things happen.

So here's why you should look around for some plausible link between the variables, some reason why one of the variables might cause the other. But even then, the lack of a link proves very little either way. There may be an independent linking variable.

Suppose smoking was a habit which most beer drinkers had, suppose most beer drinkers ate beer nuts, and just suppose that some beer nuts were infected with a fungus which produces aflatoxins that cause slow cancers which can, some time later, cause secondary lung cancers.

In this case, we'd get a correlation between smoking and lung cancer which still didn't mean smoking actually caused lung cancer. And that's the sort of grim hope which keeps those drug pushers, the tobacco czars going, anyhow. It also keeps the smokers puffing away at their cancer sticks.

It shouldn't, of course, for people have thrown huge stacks of variables into computers before this. The only answer which keeps coming out is a direct and incontrovertible link between smoking and cancer. The logic is there, when you consider what the cigarettes contain, and how the amount of smoking correlates with the incidence of cancer. It's an open and shut case.

I'm convinced, and I hope you are too. Still, just to tantalise the smokers, I'd like to tell you about some of the improbable things I've been getting out of the computer lately. They aren't really what you might call damned lies, and they are only marginally describable as statistics, but they show you what can happen if you let the computer out for a run without a tight lead.

Now anybody who's been around statistics for any time at all knows the folk-lore of the trade, the old faithful standbys, like the price of rum in Havana being highly correlated with the salaries of Presbyterian ministers in Massachusetts, and the Dutch (or sometimes it's Danish) family size which correlates very well with the number of storks' nests on the roof.

More kids in the house, more storks on the roof. Funny, isn't it? Not really. We just haven't sorted through all of the factors yet.

The Presbyterian rum example is the result of correlating two variables which have increased with inflation over many years. You could probably do the same with the cost of meat and the average salary of a vegetarian, but that wouldn't prove anything much either.

In the case of the storks on the roof, large families have larger houses, and larger houses in cold climates usually have more chimneys, and chimneys are what storks nest on. So naturally enough, larger families have more storks on the roof. With this information, the observed effect is easy to explain, isn't it?

There are others, though, where the explanation is less easy. Did you know, for example, that Hungarian coal gas production correlates very highly with Albanian phosphate usage? Or that South African paperboard production matches the value of Chilean exports, almost exactly?

Or did you know the number of iron ingots shipped annually from Pennsylvania to California between 1900 and 1970 correlates almost perfectly with the number of registered prostitutes in Buenos Aires in the same period? No, I thought you mightn't.

These examples are probably just a few more cases of two items with similar natural growth, linked in some way to the world economy, or else they must be simple coincidences. There are some cases, though, where, no matter how you try to explain it, there doesn't seem to be any conceivable causal link. Not a direct one, anyhow.

There might be indirect causes linking two things, like my hypothetical beer nuts. These cases are worth exploring, if only as sources of ideas for further investigation, or as cures for insomnia. It beats the hell out of calculating the cube root of 17 to three decimal places in the wee small hours, my own favourite soporific.

Now let's see if I can frighten you off listening to the radio, that insomniac's stand-by. Many years ago, in a now-forgotten source, I read there was a very high correlation between the number of wireless receiver licences in Britain, and the number of admissions to British mental institutions.

At the time, I noted this with a wan smile, and turned to the next taxing calculation exercise, for in those far-off days, all correlation coefficients had to be laboriously hand-calculated. It really was a long time ago when I read about this effect.

It struck me, just recently, that radio stations pump a lot of energy into the atmosphere. In America, the average five-year-old lives in a house which, over the child's life to the age of five, has received enough radio energy to lift the family car a kilometre into the air. That's a lot of energy.

Suppose, just suppose, that all this radiation caused some kind of brain damage in some people. Not all of them necessarily, just a susceptible few. Then, as you get more licences for wireless receivers in Britain, so the BBC builds more transmitters and more powerful transmitters, and more people will be affected. And so it is my sad duty to ask you all: are the electronic media really out to rot your brains? Will cable TV save us all?

Presented in this form, it's a contrived and, I hope, unconvincing argument. Not that it matters much, even switching off right now won't stop the radiation coming into your home, so lie back and enjoy it while you can! My purpose in citing these examples is to show you how statistics can be misused to spread alarm and despondency. But why bother?

Well, just a few years ago, problems like this were rare. As I mentioned, calculating just one correlation coefficient was hard yakka in the bad old days. Calculating the several hundred correlation coefficients you would need to get one really improbable lulu was virtually impossible, so fear and alarm seldom arose.

That was before the day of the personal computer and the hand calculator. Now you can churn out the correlation coefficients faster than you can cram the figures in, with absolutely no cerebral process being involved.

As never before, we need to be warned to approach statistics with, not a grain, but a shovelful, of salt. The statistic which can be generated without cerebration is likely also to be considered without cerebration. Which brings me, slowly but inexorably to the strange matter of the podiatrists, the public telephones, and the births.

Seated one night at the keyboard, I was weary and ill at ease. I had lost one of those essential connectors which link the parts of one's computer. Then I found the lost cord, connected up my computer, and fed it a huge dose of random data.

Well, not completely random, just deliberately different. I told it about the rattiest things I could dredge up, all sorts of odds and sods from a statistical year-book that just happened to be lying around. In all, I found twenty ridiculously and obviously unrelated things, so there were one hundred and ninety correlation coefficients to sift through. That seemed about right for what I was trying to do.

When I was done, I pressed button B, switched on the printer, and sat back to wait for the computer to churn out the results of its labours. The first few lines of print-out gave me no comfort, then I got a good'n, then nothing again, then a real beauty, and so it went.

At the end, I scanned the results.

I saw that NSW podiatrists' registrations showed a correlation of minus point nine eight with the number of South Australian public telephones, and minus point nine six with the Tasmanian birth rate. The Tasmanian birth rate in turn correlated plus point nine four with the South Australian public phones.

Well of course the podiatrists and phones part is easy. Quite clearly, New South Wales podiatrists are moving to South Australia and metamorphosing into public phone boxes. Or maybe they're going to Tasmania to have their babies, or maybe Tasmanians can only fall pregnant in South Australian public phone booths.

Or maybe codswallop grows in computers which are treated unkindly. As I said, figures can't lie, but liars can figure. I would trust statistics any day, so long as I can find out where they came from, and I'd even trust statisticians, so long as I knew they knew their own limitations. Most of the professional ones do know their limitations: it's the amateurs who are dangerous.

I'd even use statistics to choose the safest hospital to go to, if I had to go. But I'd still rather not go to hospital in the first place. After all, statistics show clearly that more people die in the average hospital than in the average home.

Friday, 3 October 2014

Making a sieve

Better late than never: I promised this post almost three years ago, but it slipped my mind. It will definitely help people who read Hunting the Elusive Tardigrade.  That said, the method is one which has lots of uses, including making a seed shaker.  The sky is the limit!

 You need a hammer, a chisel, a board to work on, a jar or bottle with a soft  (non-brittle) plastic lid and some mesh. Later, you will need scissors.

Put the lid on the board. and use the hammer to drive the chisel through the lid, with the cuts overlapping.
Keep going, and it begins to look like this. By the way, notice the damage done to the board by the chisel. That might have been the table!

 Now the hard work is done.
 Get the mesh.
 Cut a piece: make it a bit oversize.
 Put the lid-ring back on.
And if you must, trim the corners off.

This is the sort of idea which is widely adaptable. If you wanted, you could even use a jar like this to culture mosquitoes.  I'll get onto that one, some time soon.