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Monday 28 December 2015

Yes Monster

Right now, I am well into the second volume of Colonial Concerns, though if the first volume fails to sell to a dead-tree publisher, I will pile the two together as a Great Big e-book: I have 130,000 words in the bag, all sorts of amusing side-lights to Australian social history, and it is galloping along.

Today, I am working on the story of bubonic plague in Australia, starting with a tale that reads like a script outline for Yes, Minister! Take it from me: it's all real.

* * * * * * * *


By the 1890s, the medical profession largely accepted the idea that germs (usually referred to as bacilli) caused disease, and these things were regarded with superstitious awe. Imagine how the Victorian Board of health felt when they received an anonymous warning in late 1898 that a Dr. Haydon, living at Macarthur, near Warrnambool, had arrived from India about six months earlier, with samples of the bacilli of the bubonic plague.

There was no time to lose (other than the six months that Gray had already been in Australia!), so the Board sent a Dr. Gray to call upon Haydon to see if the covert denunciation was correct, and if it was, to try to persuade Dr. Haydon to hand the microbes over for destruction.

Haydon confirmed that he did indeed have the bacilli, saying that he had secured them for experimental, purposes, at great risk to himself, and he wanted £300 compensation if he had to hand them over. The Board, as all Boards do when faced with a contrary view, started to flap and flail.

The colonial government had no legal power to interfere with the importation, so they appealed to the Minister of Health, Mr. H. R. Williams, and this is where the comedy started. The Secretary of Trade and Customs, Dr. Wollaston, stated that everyone coming to the colony is technically bound to report everything in his possession.

Inquiries at the Customs Department showed that no such importation had been reported. Microbes are not dutiable, and there was no law to prevent their importation, but the Minister proposed sending a Customs officer to seize the germs, after which, Dr. Haydon, instead of being compensated; should be prosecuted for secretly importing the germs of a fearful and dangerous disease.

Those who have worked in bureaucracies know that Sir Humphrey Appleby has always been there. Wollaston, who was formed in that mould, saw a better way. The microbes had been imported in gelatine, opening up a legal solution. Gelatine was subject to a duty of 3d per lb. So, as Dr. Haydon had not paid the duty, the department was entitled to seize the gelatine!

Detective-Inspector Christie, who was more used to seizing illicit whisky stills, contrabrand tobacco and cigars, jewellery, and the like, was told to leave by the 4.20 p.m. train for Warrnambool, and hurry along to Dr. Haydon’s at Macarthur, where he was to seize the microbes. I like Australian Town and Country Journal’s version:

This was the first time, he had been entrusted with such a duty; and, not knowing one microbe from another, he felt nonplussed, until he was informed that he would be accompanied by a bacteriological expert in Dr. Gray, who would identify the particular parcel. Armed with a writ from Dr. Wollaston. Detective Christie left by the 4.20 p.m. train, and Dr. Gray, who was on his way back, was instructed by telegraph to join Christie and return to Macarthur. Christie was directed to seize the microbes at all hazards. This he did, and destroyed them by fire. [1]

And so, children, Australia was saved from a terrible fate of bubonic plague. Well, not quite, because the germs, if they were what they were believed to be, lacked anything that could transfer them from one person to another. And in any case, plague was just around the corner, but to learn more about that, you will need to do your own research, or read the book.


[1] Australian Town and Country Journal (Sydney), 19 November 1898, 13, http://trove.nla.gov.au/ndp/del/article/71320463?#pstart5252607

Sunday 27 December 2015

The nature of wit

Snff?  Eh? What?

Oh, yes, sorry, I drifted off there for a bit. I am hard at work writing and forgot to post anything here. No matter, here's something I prepared earlier.


To most of us, the word 'wit' appears either in the form of somebody being witty or in some way having lost their wits, and given that, it is a little hard to deal with the Biblical and formally legal expression 'to wit'. King Henry uses the expression, just before Gloucester, the future Richard III stabs him in Henry VI, Part 3. Henry tells Gloucester:

Thy mother felt more than a mother's pain,
And yet brought forth less than a mother's hope,
To wit, an indigest deformed lump,
Not like the fruit of such a goodly tree.

This reference to Gloucester's hunchback turns out to be an unwise career move on Henry's part. Again, at the end of Act II in The Merchant of Venice, a servant tells Portia

Madam, there is alighted at your gate
A young Venetian, one that comes before
To signify th' approaching of his lord,
From whom he bringeth sensible regreets;
To wit, besides commends and courteous breath,
Gifts of rich value.

So what is this wit that the characters speak of? It comes from an ancient Indo-European root meaning 'to know', and that is precisely what 'to wit' means. Variations on the term even turn up in languages like Czech, where a bear is called medved, because, as every reader of Winnie the Pooh knows, bears have a serious interest in honey.

Now honey, which yields us mead, even today, is medd in Welsh, mádhu in Sanskrit, and meodu in Old English, so it should not surprise us if the Czechs call their honey med. The second half of medved is our 'wit' in English, or wissen in German, or veta in Swedish, while in Sanskrit, we find four collections of knowledge called the Vedas. In other words, the bear, to the Czechs, is the 'honey knower'.

The verb 'wit' even turns up in an inflected form, as 'wot', mainly in poetical works, so we should not be surprised to find it awaiting us at every turn in Shakespeare, as in this comment from Cleopatra in Antony and Cleopatra:

O happy horse, to bear the weight of Antony!
Do bravely, horse; for wot'st thou whom thou mov'st?
The demi-Atlas of this earth, the arm
And burgonet of men.

Over time, the root has buried itself deep within the language. A wise person was one who knew things, and wisdom and knowledge were seen as the same, and even a wizard seems to come from that source. A witch, however, may be different — in Old English, a male witch was a wicca, while a female witch was a wicce. Some of the 'witch' trees, like witch hazel, though, are entirely free of witchery, coming instead from the linguistic root that gives us 'wicker', and meaning pliable, easily bent.

And just to confuse the issue, there is another Old English word that we now render as 'withy', generally meaning the twigs of a willow or similar tree, and sharing an origin with the Latin word for a vine, vitis, which we recognise today only in the form of viticulture. But while we may be assured that in vino veritas, in wine there is truth, there is no trace of knowledge on the vine, though intelligence of a sort often travels by way of the grapevine.

Knowledge can be found elsewhere, though. The 'wiseacre' who seems to be a modern term of contempt, has an ancient history, going back more than 400 years to a time when the wiseacre was a wise-sayer or soothsayer, not unlike the Dutch wijsseggher of the same period, or the German Weissager, meaning the same thing.

Nowadays, we seem to relate wit to a rapid response, as in a witticism, or having a quick wit. Whatever wit was, though, Francis Bacon thought it was undesirable in court, when he observed that "Judges ought to be more Learned, then Wittie".

There is one wit that is essential in any legal hearing, and that is the person called before the court to reveal what they know: the possessor of knowledge, the all-knowingness we call 'the witness'.

There is a bird of the curlew family known as the godwit, but this does not seem to have any particularly good theistic connections, and I decline to speculate in any way, shape or form about the peewit.

Saturday 12 December 2015

Keeping a log


If you want to understand a log, the place to begin is with the nautical mile, which is exactly 1000 fathoms, 6000 feet, or the distance covered by one minute of latitude. Once you understand that simple relationship, most of the rest of the calculations to do with navigation become easy indeed.

The problem with sailing away from land is that you are never quite sure what you are going to bump into, just over the horizon, because you don't know quite how far you have sailed, and while you can use sightings on the sun and the stars to work out how far you are north or south, east and west is another matter, and to sort this, you need a very accurate chronometer.

At the equator, a degree of longitude east or west is also 60 nautical miles, away from the equator it is less. If you are using a timepiece to work out where you are, the skies appear to roll past at a steady 15° each hour, which means a degree every four minutes. If your timepiece is wrong by just one minute, that is a quarter of a degree, 15 nautical miles, far enough to make the difference between safe at sea and dying of thirst in a desert.

This is why most early navigators would get to the right latitude, and then sail along carefully, until they hit their target port. One advantage of doing this was that all the calculations that are needed as you angle across the latitudes and longitudes disappear, as if you were sailing on a flat surface, rather than across a huge sphere. In fact, sailors called this 'plane sailing', though these days, we are more likely to say "it's all plain sailing from here". Incidentally, the people who praise William Bligh for his epic journey across the sea after the mutiny on the Bounty should look at the map again: Bligh was a good navigator, and made his task easier by relying on plane sailing.

When Dutch ships sailed from Europe to the East Indies, they rounded Africa, sailed east across the Indian Ocean, and then turned north, hopefully before they hit Australia, but many of them missed, and so the Great South Land became New Holland for quite a few years, due to a certain amount of bump-and-grind inadvertent discovery by Dutch seafarers who had slightly lost track of how far east they had sailed.

To avoid this sort of problem, navigators used all sorts of tricks to work out where they were, and how fast they were going. One way was to drop a log of wood over the side at a fixed point on the ship's side, and time how long it took for a second point on the vessel to reach the log.

This wasted logs, and was unreliable, so before long, the log was dropped with a line attached to it, to see how much of the line paid out in 30 seconds or 60 seconds, measured by a sand-glass.

The old dropped log was not entirely forgotten, because English sailors called this a Dutchman's log, but they soon found a better design to use.

Jeffery Walker's patent log rotator

If you multiplied the length of the line that went over the side by the correct factor of 120 or 60 (for 30 seconds or 60 seconds — you work out why!), you knew how far you would go in one hour at the same speed.

Then somebody had a clever idea: put knots in the line, and count them as they go through your hand. If these knots are 1/120 of a nautical mile (50 feet) apart, then each knot paid out in 30 seconds indicates one nautical mile an hour, while knots at 100 foot intervals are used for a sandglass period of 60 seconds.

Later, better ways were found of getting the measurement, like Walker's patent log rotator, shown on the left,

Wind and water speeds are still measured in knots (not 'knots per hour') because of this practice. Later, the 'log' grew much fancier, and even became a small propeller in a tube set into the hull, which drove a gear system to provide sea mile data.

No matter how they were obtained, the results were, of course, written in a 'log book', and that term came to apply to any record, such as the record of people accessing a computer system.

And that is why, today, we 'log on' to a computer system, though few of us spare much thought, as we do, of the horny-handed old salts who heaved lumps of wood over the side of old sailing ships.

Bloggers think about their origins even less.

Friday 20 November 2015

The devil's limitations



The devil, Old Nick, has many names. The first comes from an Old English term, déofol, which has a clear link to the Greek diabolos (which we run into most often in the form of 'diabolical', or in advocatus diaboli, discussed below). So it is little wonder we call the devil in his Satanic form "Old Nick" — quite clearly he has been around for a very long time as a doer of evil.

There is just one caveat here: the word for devil is common right across the Indo-European languages, which means devils were around long before Christianity took hold in Europe, so what was a devil originally? We may get a hint from the German word waldteufel, a wood-devil who is no more than a woodsprite. Devils, it seems, were originally just slightly malignant supernatural creatures who came to carry all of the emotional baggage assigned to Satan in the Bible, from the Garden of Eden onwards.

Yet some forms of devil, like the printer's devil, who is no more than an errand-boy, are comparatively harmless, the equivalent of what we would call a gopher today. Unless you have a taste for cheap jokes about lawyers, you would probably accept that somebody who devils for a lawyer, is fairly harmless as well. The story goes that lawyers would drink at a pub called the Devil's Head, and 'devilled' to earn what they needed to pay for drink.

It is easy to understand why a machine with sharp teeth is called a devil, or why highly seasoned foods and fireworks are called 'devils', but the devil on a ship is the seam which lies on the waterline of a ship (most commonly heard of in 'between the devil and the deep blue sea').

It is this devil plank, by the way, which is intended in the expression 'the devil to pay', according to another charming but probably erroneous etymology, which has 'paying the devil' as the act of caulking the seams on that plank. I think it may be erroneous, because there is a similar expression in French, and an opera of that name was performed as far back as the 1730s, when nautical terms were uncommon in everyday English.

Most things related to the name of the devil are bad news, or can be seen as such. Jonathan Swift called playing cards "the devil's book" — perhaps after a losing streak, but the devil's advocate, or advocatus diaboli, is on the side of the goodies. While the office is commonly misconstrued, the true role of a devil's advocate is not to argue an evil case, but to see the other side of the picture when the case is being assembled for somebody to be named a saint.

Even though printing shops have traditionally been called chapels, they are a home for printers' devils, who are boys that work in print shops. This particular devilish variant seems to have got his name from the ink that they became covered in, or perhaps the name came originally from Aldus Manutius, the famous Venetian printer who founded the Aldine Press, who was accused of having a real devil on his premises because he owned a black slave.

Aldus responded to claims that he was harbouring the devil by advertising that his 'devil' was flesh and blood, and that anybody who wished could come and pinch him. We have no record, however, of what the 'devil' thought of this generous offer.

For all that the idea of the devil is widespread, we know little enough about him — or most of us remain ignorant, and a little fearful of the devil's powers, but not Georges Cuvier, whom Aldus would have loved because Cuvier fought for freedom of the press, but today, he is recalled for his zoological skills, which he once applied to define the devil.

The famous biologist was an expert with fossils, and he liked to boast that, given a single bone, he could argue his way to a logical description of the whole animal. According to legend, Cuvier was visited one night by a joker, disguised as the devil. "Cuvier", roared the prankster as he burst in, "I've come to eat you up!"

Cuvier, was reading in bed, and he looked up calmly to consider the figure. "You have horns", he declared, "and a tail, and a cloven hoof, so you're herbivorous, and you can't!". Then he returned his attentions to his book.

Be assured, though, the devil is busy still, or so conservatives would have us believe. Once, the railway was the work of the devil, then it was electricity, heavier-than-air flight, space exploration or rock music. Now the latest alleged work of the devil is genetic manipulation, or perhaps the Internet. Isn't it odd how the devil, for all his powers, never gets ahead of the technology of humans, but just keeps pace with the latest advances?

Saturday 14 November 2015

Scotching the thistle

Thistles are a serious menace in Australia, introduced weeds that run wild. I plan here to discuss the past history of the plant in Australia, and then discuss what is involved in reducing the scourge.

I am sufficiently separated from my Scots forebears to share none of their love of the thistle, but in a time when Scots in Australia were all first-generation and sick for the lack of pibrochs, bonnie braes, and haggis and neeps, the thistle was an essential adornment for their St Andrew’s Day, Hogmanay and Burns’ Night celebrations. The thistle was also the Antipodean Scots' symbol, and as early as 1817, one James Chisholm kept a house called the ‘Crown and Thistle’ in Sydney.

In 1823, Donald M’Lean was publican at the ‘Scotch Thistle’ in Hobart. Now a word on terms: my forebears would say you could scotch a snake not kill it, and that one could drink Scotch whisky. A later generation added Scotch tape as a trade mark, but otherwise, they said, the correct descriptor was Scots. Well Onopordum acanthium, usually taken to be THE Scotch thistle, is always called Scotch. Mind you, what is meant by "Scotch thistle" is often Silybum marianum. No matter, they are all pests.

Which plant it is matters little to the Scots, who revere the thistle in a general way, because in legend, a Norseman, part of a sneak attack, yelled out in pain when he ran into a thistle, giving the alarm and saving the Scots. If it prickles a Viking, it’s a thistle. Oh, and just to confuse the issue, 19th century laymen often called it Carduus.
We are happy to observe that Mr. Gordon of Forcett, has received by one of the last ships which arrived from England at Launceston, a few seeds of a magnificent variety of the real Scotch thistle. It has been not inaptly called Carduus Burniensis, from being found originally within the iron railing which surrounds the grave of the poet Burns at Dumfries. On the 1st of June last, which is scarcely half the growing season in England, the leaves were upwards of a yard in length.
The Hobart Town Courier, Saturday 8 March 1828, 3, http://trove.nla.gov.au/ndp/del/article/4223780
Still, the Scots’ celebration of St Andrew in Hobart in 1829 (appropriately, at the Macquarie Hotel), lacked any real thistles. By 1832, the Scotch thistle was a pest in Hobart, and the fault lay, not with a Scot, but with that carousing clergyman and magistrate, Robert Knopwood (who was born in Norfolk, in case you were wondering):
A few years ago when the Rev. Mr. Knopwood lived at Cottage Green, he happened to have a Scotch thistle in his garden; the seeds of which disseminated themselves along the shore at the Battery, and the plants springing from them were admired and religiously protected by emigrating patriots of old Scotia who approached them.
 Since that time however they have become so numerous and have spread themselves so widely that almost every field and garden for miles around is more or less infested with them and the purpose of our remark at this time when the winged seeds are on the point of quitting their native pedestals, is to entreat those who have any interest in fields or gardens to use some diligence in destroying them.
The Hobart Town Courier, 28 January 1832, 2, http://trove.nla.gov.au/ndp/del/article/4200297
Two months later, a correspondent to the same paper called for urgent action to eradicate the “Scotch thistle”:
Let the Government order such a number of prisoners as may be necessary, under proper superintendence, to destroy every plant of it to be found in the neighbourhood… It is not as yet in seed, and close attention for 2 or 3 years in this manner, would, I trust, save the whole island from certain evil, the extent and injury of which is scarcely to be calculated.
The Hobart Town Courier, 3 March 1832, 2, http://trove.nla.gov.au/ndp/del/article/4200099

Well, that didn’t happen, and in 1841, the Hobart Town Advertiser suggested a new tool to its readers:
… we recommend those of our readers who intend to wage war against that most formidable pest, the Scotch thistle, to adopt the kind of hoe or spud used by Mr. Gordon, and well adapted for the purpose, as it serves also as a walking stick. It is about three inches wide, made strong, and with a staff made conveniently heavy. It is a good weapon also for snakes, or rather against these intruding reptiles.
— Quoted in The Courier (Hobart), 8 January 1841, 2, http://trove.nla.gov.au/ndp/del/article/2957324

Thistles are good at travelling, and in 1846, people were getting alarmed in Geelong, and some of them wrote to the papers about the thistles, lurking and massing, just across the Bass Strait:the invasion was coming, they warned.
… the Scotch Thistle. It is only a few years since the seed was imported, and it is already beyond the art of man to eradicate this most pernicious and useless weed. There is scarce a doubt, if the thistle is allowed to spread as it has done, that in the space of a few years it will completely destroy the pasturage, and then farewell to our wool growing prosperity. In the interior on the rich soils, the thistle grows much more vigorously than on the strong hills in the vicinity of the metropolis; some plants have a circumference of several, feet, six feet or more, and will produce some thousands of seeds; indeed the fecundity of the thistle is beyond belief.

Geelong Advertiser and Squatters’ Advocate, 25 April 1846, 4, http://trove.nla.gov.au/ndp/del/article/94444658
I have to say that when I was young, "fecund" sounded like a really rude word. The youngster within me likes to think that any word applied to thistles should be rude.  The aged hunter of the thistle that is me now, says "Fecund, fecund, fecund!".

Anyhow, in spite of what the paper said, nothing happened, and the inevitable followed, as the same paper reported in 1848:
THISTLES.-Within the last few days, the discovery has been made that this insidious weed has sprung up in several places near Geelong. Its identity with the Scotch thistle of Van Diemen’s Land has been doubted by some, but we are afraid that it will be found to be too truly so.
Geelong Advertiser, Nov. 21, http://trove.nla.gov.au/ndp/del/article/93137604
In 1849, the same paper returned to the attack:
… the rapid propagation of the Scotch thistle has been productive of incalculable injury in the neighbouring colonies, yet our colonists appear totally indifferent to the matter, although year after year rich pasture lands have become over-run with these vegetable plagues, and have been suffered to spread over the country without any efficient means being adopted for their extermination The thistle was probably imported in the shipments of hay once so frequent from Van Diemen’s Land, and made its appearance first in the neighbourhood of the flag-staff hill, Melbourne, from whence it soon spread to Keilor, but may now be found so far up as the Wardy Yallock, and unless the settlers set to work in earnest and speedily check their progress, thousands of acres of our most valuable lands will soon be rendered totally unfit for either pastoral or agricultural purposes.
Geelong Advertiser, 12 July 1849, 2, http://trove.nla.gov.au/ndp/del/article/93135028
The Argus (a Melbourne paper, printed some 70 km from Geelong) had a different view of how the thistle arrived, a few days later:
This is certainly not the true origin of the introduction of the thistle, for we well recollect it first grew on the green knoll, a little to the south of Liardet’s Inn, on the Beach, about where the residence of the Custom’s Officer is now built, and it has gradually radiated from that centre with the course of the prevailing winds. In all probability it was introduced as a garden flower, as it is said to have been in Van Diemen’s Land, by an enthusiastic Scotchman, who sent home for a supply of the thistle seed, and on its receipt took his seat on the top of the stage coach from Hobart Town to Launceston, and scattered the seeds right and left the whole way. At all events, we well recollect that when it first appeared at the spot we speak of, a “brother Scot,” we wot of, was at great pains to procure healthy specimens of “the emblem dear,” for transplantation into his garden in Melbourne.
The Argus, 16 July 1849, 2, http://trove.nla.gov.au/ndp/del/article/4775150
The Geelong Advertiser returned to the topic of thistles again later in the year, through a correspondent at Devils River, north-west of Melbourne, and now the Scots were the target:
… the Scotch Thistle … this noxious plant is now firmly rooted, and has propagated itself extensively, even in this district, one hundred and fifty miles from Melbourne and Geelong, is but too true, and threatens to overrun the soil in all directions. Last year it was noticed in some parts of this locality, but so scarce and unconnected as to create no serious apprehension; but this year however bears ample and fearful testimony of its propagating quality; thick and stubborn clumps being found, where not a vestige of its existence could be perceived before. This is particularly the case along the banks of creeks and water-courses…
The Introduction of the Scotch Thistle into the Devils’ River district was by a Scotch gentleman, who, before the dissolution of the Company, superintended the stations of the Messrs Watson and Hunter, and who it would appear, enamoured of every or anything from the ‘land o’ cakes,’ no matter how pungent or repellant, in the full bloom of his patriotism transplanted the emblem of Caledonia into the very heart of Australia Felix?

Such is patriotism! But the patriot did not stop here, he caused one of his subordinates, an unfortunate overseer, who is now a settler on this River, and who sorely repents the patriotic enthusiasm of his former superior, to plant some of the ornamental but noxious thistle in his garden. The overseer, who would not be outstripped in amor patriæ, gave some seed to others, and thus their darling thistle was nourished, nurtured, and propagated, and in due time has become to be no very great rarity…
Geelong Advertiser, 9 August 1849, 1, http://trove.nla.gov.au/ndp/del/article/93138358
 But was he right? In 1886, J. A, Froude described another way that weeds could spread, after a discussion with Captain (later Professor) Ellery at the Melbourne Observatory:
The Observatory was but a quarter of a mile distant, but in the forenoon, and under a Victorian sun, we had a mauvais quart d’heure in getting there. On the way, amidst some coarse grass, I beheld a scarlet pimpernel, the veritable ‘poor man’s weatherglass’ of northern Europe, basking wide open in the rays. If I had been studying the language of the New Hebrides, and had found imbedded in it a Greek verb, perfect in all its inflexions, I could not have been more surprised. How in the wide world came a highly organised plant of this kind to be growing wild in Australia? Had the seed been brought by some ship’s crew, or in a bird’s stomach, or been wafted over in the chambers of the air? To what far-off connection did it point of Australia with the old world? I gathered my marvel, and carried it to Mr. Ellery to be explained. How idly we let our imagination wander! He laughed as he said, ‘Many weeds and wild flowers from the old country make their first appearance in this garden. Our instruments are sent out packed in hay.’
— J. A. Froude, Oceana, 1886. 
At the end of the 19th century, an Irish-Australian politician was sure he knew which race was responsible:
A Scot introduced their charming thistle, and we will have to put a sum on the estimates to extirpate it. Edward Wilson introduced the sparrow, and the sparrow is playing havoc with our vineyards. Some busybody introduced the rabbit, and the income of Ballarat would not save us from the consequences.
— Sir Charles Gavan Duffy, My Life in Two Hemispheres, 1898.
And now, scotching the thistle

Just a note here: you can see most of these pics full-size, if you click on them.

This diatribe was brought about by my Big Game Hunt today. I am a volunteer gardener and things in the Nursery Group at the North Head Sanctuary, and one of my aims is to wipe out what we call Scotch thistle, and I am fairly sure it is Onopordum acanthium. This morning, I found two large plants, about to set seed, so I get out the Big Game Hunter's Tool Kit.

Some background: I have been working over this infested area for maybe 18 months now, mainly digging up young plants, but digging disturbs the soil and gets other weeds going, so it is preferable to use topical weedkiller. I use a benign one that requires no protective clothing.

The problem seems to have begin with one seed that grew to maturity. At some point, some idiot chopped the first plant down and left it there.  The seeds continued to escape, and we came across the infestation as the second generation was springing up.  I removed the old plant, but now we have a large seedbed to contend with, because some of the second generation reached maturity. If we stay on it, sooner or later, we will win.

The only way to wipe out thistles is to remove all the flowering and seeding heads with the small secateurs, then cut off the flowerless stems which can be left to rot, while the flowering heads are destroyed. Then the main stem, and on some of my prey today, that stem was 3 cm across, is cut with the big loppers, and the stem is then poisoned. Because there are people out there who know nothing about poisons, but have opinions, I'm not saying what it is. Suffice it to say that I know quite a bit about poisons, and I see no need for protective gear. or to argue with the ignorant, so they will get no traction here.

Now here is how the operation proceeds:

The Big Game Hunter has to infiltrate, because the plants often lie in concealment, as you can see here on the left. The Hunter has to sneak up on them, and while they quiver with rage. To get close you cut back the dead wattle bushes they are hiding in.

The flowering heads (right, above) are snipped off, wearing a raincoat and gauntlets, then the branches are taken off and inspected, working down to the base. It's slow work: it took me the best part of an hour to take out six plants — it had looked like two plants, but they were growing in a small space.

Then all that remains is for the Great Hunter to return to base, with the flowering heads of his prey in a basket, for the obligatory trophy shot, posing with one's foot on their heads, exhibiting his weapons. Thanks to Jenny Wilson for the last shot: the rest were All My Own Work.

Why kill the thistles? Simple: we have the now rare Eastern Suburbs Banksia Scrub growing on North Head, and thistles just don't belong in that.  Not only that, if the thistles got away, I suspect that the animals we are trying to protect would also face problems.

What you see in the basket, above left, is just the flowering heads and many, many seeds or potential seeds. Back to the Geelong Advertiser again:
The following is the calculation of a naturalist: “Another species of thistle called the Aranthum Vulgare, produces about 100 heads, each containing from 300 to 400 seeds. Suppose we say that these thistles produce at a medium only 80 heads; and that each contains only 300 seeds, the first crop from, these would amount to 24,000. Let these be sown, and their produce will amount to 546 millions. Sow these, and their produce, will be 13,824,000,000,000, or thirteen billions eight hundred. and twenty-four thousand millions, and a single crop from these, which is only the third years’ growth, would amount to 331,776,000,000.000,000. or three hundred and thirty-one thousand seven hundred and seventy-six billions; and the fourth years’ growth will amount 7,962,624,000,000,000,000, or seven thousand nine hundred and sixty-two trillions six hundred and twenty four thousand billions — a progeny more than sufficient to stock not only the surface of the whole earth, but all the planets in the solar system, so that no other plant or vegetable could grow, allowing but the space of one square foot for each plant.”
Geelong Advertiser and Squatters’ Advocate, 25 April 1846, 4, http://trove.nla.gov.au/ndp/del/article/94444658
I do not question the sums, and that's why we seek to scotch the thistles!