In the beginning this blog was centered on San Francisco parks and open space issues with special emphasis on natural areas and natural history. Over time it began to range into other areas and topics. As you can see, it is eclectic, as I interlace it with topics of interest to me.

I welcome feedback: just click this link to reach me.

Monday, October 17, 2011


1.    Action alert for Drake's Estero
2.   CNPS San Francisco native plant sale Saturday 22 October
3.   Urban Trails project in McLaren Park 22 October
4.   Feedback
5.   Sandhill Cranes talk by Paul Tebell October 20 in San Francisco
6.   Barbara Jordan and immigration reform
7.   Submit question on immigration and population for candidates debate Oct 18
8.   Mary Oliver has some questions for you
9.   Alex the parrot has a vocabulary of 150 words, has his own foundation
10. Parrot with coherent line of invective, from watching TV
11. World in the Balance: Historic Quest for a Universal System of Measurement 

1.  The ecological heart of Point Reyes National Seashore is Drakes Estero, the only marine wilderness on the West Coast.

It turns out though...
Powerful forces are seeking to maintain a private, commercial business within this environmental jewel.

In response to the Drakes Bay Oyster Company’s (DBOC) request to produce oysters for ten more years in Drakes Estero, the National Park Service (NPS) has released a Draft Environmental Impact Statement (DEIS).

The Draft EIS makes clear the NO ACTION ALTERNATIVE, which would terminate the current oyster company permit on November 30, 2012, is the best alternative for the Drakes Estero environment and according to federal wilderness law, science, and National Park Service policy on natural resources conservation and restoration.

The three action alternatives each permit the private, commercial oyster operation to exploit Drakes Estero for ten more years, which the Draft EIS makes abundantly clear would have long-term adverse environmental impacts on wetlands, eelgrass habitat, native fish, harbor seals, resident and migratory birds, endangered species and the wilderness and National Park experience.

Point Reyes National Seashore needs your help!

Send in your comments on the Draft EIS to the National Park Service.
Check out our attached TALKING POINTS for your information and convenience in drafting your comments.

The Park Service will hold three open house public meetings to gather your comments:

Tuesday, October 18, 2011, 6-8 pm 

Dance Palace Community Center (directions)

503 B Street Point Reyes Station CA 94965

Wednesday, October 19, 2011, 6-8 pm 

Fort Mason Center, Building D (directions - map of Fort Mason Center)

Marina Boulevard at Buchanan
 San Francisco CA 94123

Thursday, October 20, 2011, 6-8 pm 

Tamalpais High School Student Center (directions - map of Tamalpais High School)

700 Miller Avenue Mill Valley CA 94941

The deadline for comments to the Draft EIS is November 29, 2011.
The DEIS webpage is here:


2.  Join us at the California Native Plant Society Yerba Buena Chapter Native Plant Sale!

Please note the new time and location:
Saturday, October 22nd from 1 pm to 5 pm
350 O'Shaughnessy Blvd (at Del Vale)

“For man, autumn is a time of harvest, of gathering together.  For nature, it is a time of sowing, of scattering abroad.”   
    Edwin Way Teale

Fall is the ideal time for planting. The Annual Plant Sale is Yerba Buena Chapter’s primary source of funding; it enables us to put on our programs --and strive to fulfill our mission. Get great plants for your garden and help support CNPS!
Cash and checks (sorry, no credit cards) will be accepted for plant and book sales. (Membership applications accept credit info. Please join us!) For additional information, or to volunteer to help with the plant sale, contact Ellen Edelson (415-531-2140 or

The Yerba Buena Native Plant Sale is an opportunity to find a great many native plant species that aren’t readily available at garden centers. Our focus and offerings, as always, will be native plants local to our chapter area: San Francisco and northern San Mateo County, including Montara and San Bruno Mountains. These are the
species already adapted to our area’s climate, soils, and habitats--and are also important to our local fauna.  Many of the plants for sale will have been grown by chapter volunteers from seeds, cuttings, or divisions-- from garden plants or other sources from our chapter area. Great efforts are made to learn the provenance of the plants at our sale, as we understand the importance of maintaining a local gene pool.  Growing locally native plants in your garden is an important way to:

Attract pollinators, including native bees, butterflies, moths, and birds--for your pleasure and their benefit
Provide for endangered species (such as by growing host and nectar plants for the Green Hairstreak butterfly)
Enhance corridors for native wildlife
Use less water (thereby less energy pumping that water)
Save money on utility bills
Reduce the use of fertilizers and pesticides
Have a beautiful, colorful, lively garden
Inspire your neighbors to do the same!

To assist with your plant selections, you will find:
A plant list of our 2011 offerings on our website prior to the sale
Articles and links on “Gardening with Natives“–always on our website
Plants grouped roughly according to their general plant community of origin
Signage indicating the plant type, habit, size, soil preferences, and wildlife interest for each species
Photos of the flower and/or form of each plant
Volunteers with native gardening expertise roaming the room
Books and other materials available for reference
Books and posters will also be available for purchase.


3.  The first Urban Trails project is going to be from 9am-12pm at McLaren Park on 10/22. 

We will be meeting in the parking lot off of Shelley Drive just above the dog play area and reservoir.  This project will be building one of the remaining sections of the Philosopher's Way trail, which is an art installation comprised of various navigable routes designed to encourage personal contemplation while quietly revealing McLaren Park's systems of ecology, geography, and history.  Philosopher's Way will highlight the sense of place for park users by offering visual and physical associations between the place where they are in the park and views of surrounding neighborhoods, cityscapes, and prominent Bay Area landmarks such as Mount Tamalpais, Mt Diablo, San Bruno Mountain, and the Pacific Ocean.

No trail-building experience is necessary, we will provide all tools training and snacks.  Call Joe Grey at 415-831-6328 to sign up or


4.  Feedback

Alice Polesky:
Hi Jake,
Here's a website that attempts to raise people's awareness about the impact of 7 billion humans. You put in your birthday, and it tells you what your number in the 7 billion is:

My number (I was born in January 1946) is 2,359,698,643.

Scary stuff.
And mine is 2,021,290,697.  World population increased only 337,407,946 in the 19 years between my birth and yours--but since your birth, 4,640,301,357 have been added!

On the site, racking up the figures is like at the gas pump:  On the right the numbers are whizzing so fast you can't read them.  That's what this population clock does.

Proximity makes the heart grow colder

Jerry Cadagan:
Jake -- Regarding item 5 (SF lusting after more Tuolumne River water) there is an aspect of this issue that is not getting enough attention.  Sure, SF and its 26 wholesale customers might need a bit more water as populations grow.  But most water is not used for human consumption.  It's used for watering median strips and parks, washing cars, and irrigating golf courses, etc.  More and more of those purposes are being fulfilled with recycled water throughout the state.  But where is San Francisco when it comes to the use of recycled water?  Zip, Zero, Nada.  The State Water Board recently released an updated survey of municipal water recycling facilities.  It's at  -

SF sticks out like a sore thumb as the only county or city of any significance that does no water recycling.  And there are something like 5 or 6 municipal golf courses, lots of parks and all of Golden Gate Park that are being irrigated with potable (drinkable) water.

My good friends at SFPUC will tell you that they are thinking about it, working on it, studying it, hiring consultants to tell them how to do it --- and on and on.  The message to them should be "Do It!"

Jerry Cadagan

No more Tuolumne River water should go to SF until it enters the 21st Century and gets in to water recycling; and then they won't need more water from the Tuolumne.

Anna-Marie Bratton::
Hi Jake,
1)  I had an aunt that lived on the outskirts of Little Rock Arkansas; it was quite easy to see Wood Thrushes very near her house,  as long as I got up very early and went to the edge of the wood. Those were, indeed, magical mornings.  Laurie Lewis is a local singer/song writer who has a very haunting song about the loss of Wood Thrush habitat - here are two ways of getting to a utube audio/video of her  singing the song.  Direct link to utube video  Laurie Lewis website with link to utube video

2) Unless there is a crustacean with the common name of Springtail that I don't know of, you're incorrect.  Springtails are a primitive, wingless insect of the order Collembola.  There is a crustacean that is laterally flattened and jumps around in similar fashion to the Springtail;  that is the Beach Flea - or sometimes called a Scud (an Amphipod) - perhaps that is what you are referring to, but it has no "tail" tucked under its body with which to spring, it jumps around using its legs.
Anna-Marie:  Thanks so much for setting me straight on springtails.  The pictures sure do look a lot like what I see in the park leaf litter.

By odd coincidence, in the October 15 geology field trip to see radiolarian chert, we were hiking through Mt Sutro woods and our curiosity became focused on these very organisms.  I was anxious to display my new-found knowledge:  "Oh, these are not crustaceans, they are insects in the genus Collembola", I pronounced authoritatively.  Next day, I received this email from field trip leader Paul Heiple:

I checked on those odd critters in the leaves, they are Crustaceans known as lawn shrimp, Arcitalitrus sylvanicus.  They are not native and they are not springtails.  Check out the link:

Hmm.  They do indeed fit the description and circumstances to a T.


5.  Golden Gate Audubon features Paul Tebell on Sandhill Cranes October 20

Every winter, these large, long-legged birds occupy the fields and marshes south of Sacramento, providing great opportunities for nature enthusiasts to view them. But what do you watch for? Join crane biologist Paul Tebbel as he tells you all about these fascinating birds and describes how to identify and appreciate the verbal and body signals cranes send to one another. You’ll learn to recognize juveniles, tell subspecies apart, and distinguish between dancing and aggression. The presentation features a video of cranes showing the behaviors up close, with Paul acting as narrator.

Paul Tebbel, executive director of the Effie Yeaw Nature Center on the Lower American River in Sacramento, did his first research on Sandhill Cranes in 1976  in Michigan’s Upper Peninsula. From 1995 to 2006, he was the manager of National Audubon’s Rowe Sanctuary on the Platte River in southern Nebraska. Nearly 750,000 cranes use the Platte every spring, and Rowe Sanctuary often contains more than 65,000 birds every night.  In 2000, Paul and another “craniac” started giving crane behavior seminars at the Festival of the Cranes at the Bosque del Apache National Wildlife Refuge in New Mexico. November 2011 will be the 12th year of this workshop, and Paul is bringing a similar seminar to the Sandhill Crane Festival in Lodi in early NovemberFollow the 80-20 Rule

Join us October 20 at 7:00 p.m. for a half-hour of socializing and refreshments Program starts at 7:30 p.m..
San Francisco programs are held at the First Unitarian Universalist Church and Center located at 1187 Franklin Street (at Geary) zip 94109. Map it!

More information on our website at

The November Speaker Series will be held in Berkeley on November 20 on the Brazilian Pantanal with Paul Donahue.   There will be no Speaker Series event in December.


6.  Barbara Jordan and Immigration Reform, by Ric Oberlink

The U.S. Postal Service recently issued a stamp to honor Barbara Jordan, offering us an appropriate moment to reflect upon the life of this remarkable woman and her contributions toward resolving a complex and contentious issue that continues to resonate.

In December 1993 I was participating in a roundtable of the U.S. Commission on Immigration Reform in Los Angeles when, during a lunch break, a perceptible buzz circulated among attendees—President Clinton had named the former Texas Congresswoman as Chair of the Commission. I was excited at the prospect that the appointment of this esteemed civil rights advocate would draw appropriate attention to this important issue, but, as one who believes that population growth and the immigration that drives it place inordinate strains on our environment and infrastructure, I was concerned that she would fall into the maelstrom of liberal clichés offered by her base of supporters. As the environmentalist Edward Abbey said about immigration, “The conservatives love their cheap labor; the liberals love their cheap cause.”

Instead, Jordan and the Commission members undertook a thorough, comprehensive examination of American policies on legal and illegal immigration. Over five years, the Commission held 13 consultations and 15 roundtables with experts and scholars; commissioned 18 research papers; held eight public hearings across the nation; and conducted seven site visits.

The culmination was a series of forthright recommendations commensurate with the problem. Rejecting amnesty proposals, Jordan testified to Congress, “Credibility in immigration policy can be summed up in one sentence: those who should get in, get in; those who should be kept out, are kept out; and those who should not be here will be required to leave.”

Reflecting upon the impact of immigration on America’s working poor, a problem that is particularly worrisome during this long recession, the Jordan Commission stated, “Immigrants with relatively low education and skills may compete for jobs and public services with the most vulnerable of Americans, particularly those who are unemployed or underemployed.” Ultimately, the Commission concluded not only that the United States must enforce its laws against illegal immigration, but also that it should reduce legal immigration by one-third.

President Clinton embraced the proposal to cut immigration. His press secretary announced that “the President indicated to Barbara Jordan today that he will support such reductions.” Clinton then confined the Commission’s report to a shelf where it continues to gather dust.

Even more astonishing, when viewed from today’s highly polarized political world, was the bipartisan agreement on the Jordan Commission. After more than five years of exhaustive study of this highly controversial policy matter, the five Democratic and four Republican appointees were unanimous in virtually all of their major policy recommendations.

Immigration policy will remain contentious for the foreseeable future, and there is always room for debate about what is the appropriate level of immigration. However, had Clinton and Congress, and subsequent Presidents and Congresses, taken steps to implement the Commission’s recommendations, we would have resolved many of the immigration problems we now face. States would not feel compelled to pass laws to assist in immigration enforcement if the federal government had not abrogated its duties.

President Obama and many others claim they support “comprehensive” immigration reform. They should review, as a starting point, the prodigious work done by the U.S. Commission on Immigration Reform, the most extensive examination ever taken of American immigration policy. Barbara Jordan told Congress, “It is both a right and a responsibility of a democratic society to manage immigration so that it serves the national interest.” The “national interest.” Now there is a subject on which today’s politicians could use a refresher course.

Ric Oberlink, J.D., is a Senior Writing Fellow at Californians for Population Stabilization.


7.  Alert! Submit questions on immigration and population for the presidential candidates' debate!

CNN, along with the Western Republican Leadership Conference, will host  the Western Republican Presidential Debate on Tuesday, October 18, 2011,  in Las Vegas, Nevada.

You can submit questions for tomorrow's CNN Western Republican presidential debate by clicking here . 
Compose a question of your own or select one of our suggestions below to type in as a submission:

1. Given that there are 14 million unemployed Americans, shouldn’t we hire them for jobs instead of giving those jobs to foreign workers through our policy of massive immigration?

2. The Obama administration has failed to enforce our immigration laws and instead instituted legal action against several states that have passed laws to assist in apprehending illegal aliens. Will you take the same approach?

3. Do you endorse mandatory E-Verify legislation so that jobs in the United States will go to legal American workers?

4. Our unemployment rate is not coming down. Why does the federal government give out 1.5 million green cards and other work permits to foreign workers each year?

5. Do you favor reducing both legal and illegal immigration so that we can stabilize the US population within the next few decades?

6. Our last major amnesty in 1986 led to the present situation where we have 12 million illegal aliens in this country. Now there are demands for another amnesty. Do you promise that you will not sign legislation that gives an amnesty to illegal aliens?

7.  The American worker sees no difference between “outsourcing” jobs, and “insourcing” jobs, bringing in foreign workers to take American jobs. Will you do anything to reduce the number of new foreign workers allowed in by the federal government?

8. Ten years after 9-1-1, our borders are still not secure. Will you secure our borders?

9. The Obama admin. issued an administrative amnesty memo. that allows illegals to remain here and receive work permits, even though we have massive unemployment here. Will your administration also give a pass to those who break our immigration laws?

10. Since there are 14 million unemployed Americans and 22 million underemployed Americans, will you reduce the importation of foreign workers, both permanent and temporary?

11. In California, the unemployment rate is 12 percent. Will you support requiring all employers in the United States to use the E-verify program to reduce the unemployment of legal workers?

12. Each year, the federal government brings in 1.5 million new foreign workers. Since we have massive unemployment here, shouldn’t that number be reduced?

13. Many businesses use the H-1B visas to hire foreign workers at lower wages. Do you support the efforts of Senators Grassley and Durbin to end abuses in the program so that jobs must first go to qualified American workers?

14. Because of high levels of legal and illegal immigration, the Census Bureaus projects that the U.S. population will grow to 440 million by 2050. Is this rapid growth sustainable, and, if not, what will you do to restrain it?


Have You Ever Tried to Enter the Long Black Branches?

Have you ever tried to enter the long black branches
of other lives --
tried to imagine what the crisp fringes, full of honey,
from the branches of the young locust trees, in early morning,
feel like?
Do you think this world was only an entertainment for you?
Never to enter the sea and notice how the water divides
with perfect courtesy, to let you in!
Never to lie down on the grass, as though you were the grass!
Never to leap to the air as you open your wings over
the dark acorn of your heart!
No wonder we hear, in your mournful voice, the complaint
that something is missing from your life!
Who can open the door who does not reach for the latch?
Who can travel the miles who does not put one foot
in front of the other, all attentive to what presents itself
Who will behold the inner chamber who has not observed
with admiration, even with rapture, the outer stone?
Well, there is time left --
fields everywhere invite you into them.
And who will care, who will chide you if you wander away
from wherever you are, to look for your soul?
Quickly, then, get up, put on your coat, leave your desk!
To put one's foot into the door of the grass, which is
the mystery, which is death as well as life, and
not be afraid!
To set one's foot in the door of death, and be overcome
with amazement!
To sit down in front of the weeds, and imagine
god the ten-fingered, sailing out of his house of straw,
nodding this way and that way, to the flowers of the
present hour,
to the song falling out of the mockingbird's pink mouth,
to the tippets of the honeysuckle, that have opened

in the night
To sit down, like a weed among weeds, and rustle in the wind!
Listen, are you breathing just a little, and calling it a life?
While the soul, after all, is only a window,

and the opening of the window no more difficult
than the wakening from a little sleep.
Only last week I went out among the thorns and said
to the wild roses:
deny me not,
but suffer my devotion.
Then, all afternoon, I sat among them. Maybe
I even heard a curl or tow of music, damp and rouge red,
hurrying from their stubby buds, from their delicate watery bodies.
For how long will you continue to listen to those dark shouters,
caution and prudence?
Fall in! Fall in!
A woman standing in the weeds.
A small boat flounders in the deep waves, and what's coming next
is coming with its own heave and grace.    

Meanwhile, once in a while, I have chanced, among the quick things,
upon the immutable.
What more could one ask?
And I would touch the faces of the daises,
and I would bow down
to think about it.
That was then, which hasn't ended yet.
Now the sun begins to swing down. Under the peach-light,
I cross the fields and the dunes, I follow the ocean's edge.
I climb, I backtrack.
I float.
I ramble my way home.

~ Mary Oliver ~
(West Wind: Poems and Prose Poems)

9.  Alex the African Grey
My parrot and I

Oct 23rd 2008 | from The Economist

Illustration by Daniel Pudles
THE young Irene Pepperberg was not the only child to have been enthralled by the “Dr Dolittle” stories, in which a doctor is taught the language of animals by his parrot. But it is unlikely that anyone will match her tenacity in trying to make the stories come true. For the past 30 years, Dr Pepperberg, who studies parrots at Brandeis University in Massachusetts, has been producing research papers on the cognitive abilities of her African Grey, Alex, who died in September 2007 and who was the subject of an Economist obituary. In “Alex & Me” she has written a memoir of two unusual scientific careers, one of them pursued—not exactly by choice—by a bird.

As a lonely child in Brooklyn, Dr Pepperberg owned pet birds from the age of four, and daydreamed about being able to understand animals’ thoughts. A socially awkward chemistry student at the Massachusetts Institute of Technology (MIT) in Boston, she writes that talking to her parakeet was often her “only non-work-related exchange of the whole day”. It hardly comes as a surprise that she decided to switch from chemistry to the study of animal communication. When a pet-shop owner picked out an African Grey for her in 1977, she says she already expected that it would come to change the way people thought about the minds of animals.

Thus she knew from the start what she wanted to prove. That may seem suspiciously overconfident, but Dr Pepperberg certainly obtained some striking results. Alex (his name supposedly an acronym for Avian Learning Experiment) eventually learned the names of about 50 objects, knew the numerals from one to six, could perform simple addition and used categories such as similarity and difference, shape, colour and material. He apparently combined words to make up his own expressions (“yummy bread” for cake, for example). He also seemed to combine phonemes to construct new words. Lacking lips, he could not pronounce the letter “p”, so his term for an apple was “banerry” (apparently mixing “banana” and “cherry”). Most unnerving of all, he would make spontaneous remarks in appropriate circumstances, such as “What’s your problem?” and “I’m gonna go away now.”

The efforts required to bring forth such little marvels were immense. For the first 15 years of his life, Alex was talked to by his trainers for eight hours each day. Dr Pepperberg adapted the so-called “Model/Rival” method developed by a German ethologist in the 1970s; this uses two experimenters, one of whom, A, “teaches” the other, B, while sometimes switching attention to the parrot. In Dr Pepperberg’s version, A and B alternate their roles, to mimic the social context in which children learn to speak.
Finding the money for such labour-intensive research has been a constant struggle, and Dr Pepperberg relies on private donors and the generous help of volunteers. There is little sign, however, that other labs will be able to devote the enormous efforts required to replicate her work, as scientific method requires. Unfortunately for Alex’s legacy, this may mean that he comes to be remembered as little more than a unique curiosity.


More on bird brains: 

The world lost its most famous bird brain this month: Alex, an African gray parrot who lived in a Brandeis laboratory and possessed a vocabulary of nearly 150 words. Yet as remarkable as Alex was - he could identify colors and shapes - he was not alone. The songs of starlings display a sophisticated grammar once thought the sole domain of human thinking. A nutcracker can remember the precise location of hundreds of different food storage spots. And crows in Japan have learned how to get people to crack walnuts for them: They drop them near busy intersections, then retrieve the smashed nuts when the traffic light turns red.

These feats are part of a growing recognition of the genius of birds. Scientists are now studying various birds to explore everything from spatial memory to the grammatical structure of human language. This research is helping to reveal the secrets of the human brain. But it is also overturning the conventional evolutionary story of intelligence, in which all paths lead to the creation of the human cortex. The tree of life, scientists are discovering, has numerous branches of brilliance.

Website for the Alex Foundation (yes, he rates a foundation!).  It is temporarily inactive, but visit it anyway for the links, which are presently active:


10.  A parrot with a remarkably coherent line of invective has been given a private pen at a wildlife sanctuary, after swearing repeatedly at distinguished visitors, including a mayor, a vicar, and two police officers.

Barney the five-year-old macaw can now be seen only on special request, like the British Library's collection of erotic books.

Trained by a previous owner who had a dislike of authority, he initially appeared to be a potential draw at the Warwickshire Animal Sanctuary because of his vivid blue and gold plumage and his habit of saying "Thank you, big boy," when given a digestive biscuit.

But his other side was revealed when a civic party came on a tour of the sanctuary and Barney spotted the mayor's chain and the woman vicar's dog collar.  Instead of the Benedicite ("Oh all ye fowls of the air, bless ye the Lord"), he told the mayor:  "Fuck off," before turning to the vicar and saying:  "You can fuck off too."

The sanctuary's owner said:  "To their credit they didn't take offence and laughed it off--and luckily so did two policemen who were told:  "And you can fuck off, you wankers."

The parrot is thought to have kept up its watching TV after the 9 pm watershed.

                           Guardian Weekly 5-11 Aug 05

(Forget January 5 - this is an oldie.


Photos of Americans taken between 1939 and 1943, from the Library of Congress archives.



A history of measurement

From yardsticks to metre rule

A history of greater and greater accuracy

Oct 8th 2011 | from The Economist

 The long and the short of it

World in the Balance: The Historic Quest for a Universal System of Measurement.
By Robert Crease.

A GOOD unit of measurement, writes Robert Crease, must satisfy three conditions. It has to be easy to relate to, match the things it is meant to measure in scale (no point using inches to describe geographical distances) and be stable. In his new book, “World in the Balance”, Mr Crease, who teaches philosophy at Stony Brook University on Long Island and writes a column for the magazine Physics World, describes man’s quest for that metrological holy grail. In the process, he shows that the story of metrology, not obvious material for a page-turner, can in the right hands make for a riveting read.

The earliest known units met the first two of Mr Crease’s requirements well. Most were drawn from things to hand: the human body (the foot or the mile, which derives from the Latin milia passuum, or 1,000 paces) and tools (barrels, cups). Others were more abstract. The journal (from jour, French for “day”), used in medieval France, was equivalent to the area a man could plough in a day with a single ox, as was the acre in Britain or the morgen in north Germany and Holland.

But no two feet, barrels or workdays are quite the same. What was needed was “a foot, not yours or mine”. Calls for a firm standard that was not subject to fluctuations or the whim of feudal lords, grew louder in the late 17th century. They were a consequence of the beginnings of international trade and modern science. Both required greater precision to advance.

In response the metre, from the Greek metron, meaning “measure”, was ushered in, helped along by French revolutionaries, eager to replace the Bourbon toise (just under two metres) with an all-new, universal unit. The metre was to be defined as a fraction of the Paris meridian whose precise measurement (in toises) was under way. Together with the kilogram, initially the mass of a decaliter of distilled water, it formed the basis of the metric system.

Successful French metrological diplomacy meant that in the ensuing decades the metric system supplanted a hotchpotch of regional units in all bar a handful of nations. Even Britain, long wedded to its imperial measures, caved in. (Americans are taking longer to persuade.) In 1875 Nature, a British magazine, hailed the metric system as “one of the greatest triumphs of modern civilisation”. Paradoxically, Mr Crease argues, it thrived in part as a consequence of British imperialism, which all but wiped out innumerable indigenous measurement systems, creating a vacuum that the new framework was able to fill.

For all its diplomatic success, though, the metre failed to live up to its original promise. Tying it to the meridian, or any other natural benchmark, proved intractable. As a result, the unit continued to be defined in explicit reference to a unique platinum-iridium ingot until 1960. Only then was it recast in less fleeting terms: as a multiple of the wavelength of a particular type of light. Finally, in 1983, it was tied to a fundamental physical constant, the speed of light, becoming the distance light travels in 1/299,792,458 of a second. (The second had by then itself got a metrological makeover: no longer a 60th of a 60th of a 24th of the period of the Earth’s rotation, it is currently the duration of 9,192,631,770 periods of a phenomenon called microwave transition in an atom of caesium-133.)

Now the kilogram, the last artefact-based unit, awaits its turn. Adding urgency is the fact the “real” kilogram, stored in a safe in the International Bureau of Weights and Measures in Sèvres, near Paris, seems to be shedding weight relative to its official copies. Metrologists are busy trying to recast it in terms of Planck’s constant, a formula which is deemed cosmicly inviolate, as is the speed of light (pending further findings from CERN, anyway). In his jolly book, Mr Crease is cheering them on.

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