Tom Womack

Imagine my shock to discover that Paris in the spring-time is in fact pretty much as nice as it's advertised to be. I'm in a hotel at the bottom of the butte de Montmartre, so I walked up to Sacre-Coeur, walked from there to Notre-Dame, visited the Sainte-Chapelle, walked along the Seine to place de la Concorde to have tea at Ladurée (the shop that invented the macaroon), then back to Montmartre to stuff myself to a truly ridiculous degree with cassoulet.

La Madeleine struck me as a church designed by somebody who'd rather be designing a secret-police headquarters; it's a Greek temple without the setting, very four-square and bleak from the outside.

Have I just not noticed the parts of English towns with green copper roofs, gilded statues, and the name of the building carved inches deep and picked out in gold leaf, or is that an architectural style incompatible with English weather?

Tomorrow, Afghan gold, the Arc de Triomphe and La Defense, and possibly Pierre Hermé's patisserie; I've heard him described as the Heston Blumenthal of the cake world, which would probably be enough to draw me to Paris on his own. The Bulgarian-treasures exhibit advertised on Eurostar has unfortunately already moved to Basel, the unannotated date on the document was the closing date not the opening date.

I have on my desk the replacement for the computer I bought at the start of the year which exploded three hours after purchase.

I've had it for not quite a week. It persistently crashes, apparently sometimes corrupting parts of the hard disc, when I give it certain fiddly disc-intensive calculations to do. Sometimes it crashes under other circumstances. Is Ubuntu 6.10 known to be this irredeemably unreliable on contemporary Intel hardware, or have I just received my second lemon in an order of two?

It's running memtest86 overnight, but no faults have shown up yet; I suspect this is a disc-controller rather than a memory issue, and no faults will show up. The last memory issue I had -- a module which had an unshakeable faith that every 1024th bit in the memory it presented had to be reported as zero whatever had been written to it -- showed up immediately in memtest86.

Is there a disc equivalent of memtest86? I'm prepared to take backups of everything - there's not much novel, I've only had the machine a week - and sacrifice the disc contents should the test need to be destructive, though I'd prefer something that sat in userspace and confined its merciless thrashing to the bits of the disc on which my data isn't.

Elizabeth Moon, Winning Colours. Third in a series of Ruritanian space-operas, combining somehow the traditions of planet-spanning military fiction with the dramatic conventions of the Famous Five. Almost all problems are resolved by the intervention of powerful relatives. Fluffy comfort reading; third in a sequence of apparently six, though I'm warned off numbers 4 and 5.

K J Parker, Devices and Desires. An unusually-smart engineer is wronged by the government of his city-state, who have secured dominion over the world by jealously guarding the secret of Mass Production. His plan to get back to his family is a Heath Robinson machine with armies and kings as its components. Told through the eyes of a series of nicely wry narrators.

Elizabeth Moon again, Speed of Dark. Told by an autistic narrator, who struggles gently with the world but manages mostly to get by; let down by a peculiar ending and an unreasonably evil villain with a lack of self-awareness enough to embarrass me through the pages. I'm not keen on autistic narration - The story of the dog in the night-time I found unreadable - but this worked better.

William Manchester, American Caesar. Somewhat hagiographic biography of Douglas MacArthur, a character whose ubercompetence and impossible manner one would think over-done in a work of fiction. This is bits of history that I hadn't really encountered before: the First World War from the American point of view, the Pacific War - I really hadn't realised how much of it took place in New Guinea, or of what scale the Japanese forces in random Pacific hells were - the occupation of Japan and the war in Korea. Very interesting.

Stanislaw Lem, Imaginary Magnitude. This one's amazing; the conceit is that it's a collection of prefaces to future books, the first half is a collection of wonderful big-idea short stories, and the second a solid approach to the philosophical problems posed by superhuman artificial intelligences. Makes most science-fiction writing seem childishly basic, there's a sort of sharp, precise competence to it.

Larry Niven, Protector. Fun to read, and must have been great fun to write; this is an alien-contact story coupled with a mastermind-driven heist tale. I have a very odd angle on Niven, after reading Tales of Known Space, a collection of short stories and of descriptive writing about his Known Space setting, before actually reading any Known Space works.

George R R Martin, Fevre Dream. If you want pre-Civil-War Southern decadence, with hot humid forests, the romance of the river-boats, violence, slavery and vampires, this is the book for you. Definitely good.

R A Macavoy, The Belly of the Wolf. This one's more difficult to describe: what I like of it is the extremely calm style of the writing, I can't now recall the sequence of events at all.

Karl Schroeder, Sun of Suns. Another fun one, a picaresque set in floating cities, illuminated by their own petty nuclear suns, inside a floating spherical world with a great nuclear sun at the centre and where the water-vapour freezes into iceberg-sized icicles at the edge. You get the impression that the author has run the climate models to see how the clouds would behave and how the trees would grow, and then decided to set the action for his own amusement. Feathered fish, air-pirates, and Sargassoes of the sky.


Do any of my readers wish to borrow any of these (Devices and Desires is already lent out); can anyone suggest books I'd be interested in reading given what I thought of these ones; does anyone dispute my reviews?

It was a gorgeous day today, and I went with my parents to Minsmere (the collection of artfully-shaped swamps and heaths here, just up the coast from Sizewell; don't reed-beds look odd in satellite images?). It felt as one would expect unmodified ground to, though the satellite picture makes it clear that it's as managed as any stately-home garden.

At one stage I left the camera on entirely the wrong exposure settings, so shot a sequence of deeply overexposed frames of a flying seagull: obviously most of these were junk, but one was really quite striking:

( Click for more birds )

I think, for a usefully peculiar news perspective, I'm inclined to recommend chinadaily.com.cn even over english.aljazeera.net. Lots of entertaining Kremlinology (presumably should be Zhongnanhaiology, but that's not exactly a catchy word) to be done on what topics are permitted to be portrayed in the offensively-harmless cartoons. Also, baby pandas.

The Sichuan Wolong Panda Centre, having finally figured out how to artificially inseminate pandas reliably, is now overrun with baby pandas.

The only problem is that Bayes's Theorem, plus the strong resemblance between baby pandas and toy pandas, means your first seven or eight thoughts are 'why are these serious-looking Chinese scientists posing with sixteen toy pandas?'

PS: additional baby pandas here, baby polar bear here ... I notice that China Daily has rather more cute baby animal photos than serious Western papers tend to.

Took about two hours in three sessions, quite a lot of digging, the use of both (borrowed; thanks rmc28) axe and mattock, and some blisters on my hands; I'm very thankful that leylandii don't have tap-roots, I'm not sure what I'd have done in that case.

Now all I have to do is fill in the hole where the stump was, and I'll never trip over it again. Is rotting wood a good fertiliser?

Enlivened by the comet, I went up Castle Hill again, with my birding lens and nice new tripod.

After one or two bits of infrastructure-building - figuring out the format of the sensor-data part of Nikon's .NEF files (the last 9728000 bytes of the file contain 2000 lines, each of 3040 samples packed as 304 16-byte chunks, with each chunk containing ten 12-bit numbers packed two-in-three-bytes as 0xAA 0xAB 0xBB and a final 0x00) and implementing dark-field subtraction because the D100's sensor, especially at high ISO, is plagued with hot pixels, I got some reasonable shots.

The problem is, the star images are big and ugly. I'd calculated, based on a pixel size of 7.8 microns, that a star would move three pixels in a 1.6-second exposure at 170mm, or one pixel in a 0.3-second exposure at 500mm. I'd noticed that it took a while for vibrations in the tripod to settle, so used self-timer to let it settle before taking the shot. But still a star at 500mm is fifteen pixels across on the 0.3s-exposed image. Seeing in Cambridge isn't great, but it's not likely to be as dreadful as 45 arc-seconds.

My guess is that I'm not focussing correctly. But I'm not sure how I focus correctly; there's no light, so auto-focus just hunts back and forth and gets nowhere, turning the focus dial until it hits the infinity end-stop doesn't seem to be sufficient; my eyes can't distinguish a perfectly-focussed star from a slightly out-of-focus star. Towards the end of the session, taking photos pointed pretty much straight up with the lens at 500mm, I was getting images trailed by movement of the tripod rather than the stars, but that's more a matter of waiting for a season where the interesting object isn't at the zenith.

[ For taking pictures of stars, I think the figure-of-merit is focal length / f_stop^2; the permitted exposure before the motion of the stars blurs them is proportional to 1/focal_length, and the amount of light that gets in is proportional to the lens area = (fl/ap)^2. For star-fields, it's 1/(fstop^2 * focal length), since the area of sky you see, and so the number of stars, is proportional to 1/fl^2. 50/1.4 lenses are what this measure tells one to lust after ]

Is there anyone reading this who lives in Cambridge.uk, owns an axe, and would be willing to come round for a few minutes one evening and chop through a number of rather solid tree-roots (several about as thick as my arm, and one about as thick as my calves) for me? I will cook them curry, or something other than curry if they'd prefer, in return.

This seems the right time of year for major garden-fettling, since the annuals from last year are dead and I haven't got round to planting anything in the large areas which are getting covered in earth as I try to dig out the least conveniently-placed of the three tree-stumps with which earlier renters have gifted the garden. The house came with 45 large brown bricks in a pile, which I think will make a good path down the middle of the back bit of the garden, but the tree-stump is inconveniently in the way.

New Year's Day is a foolish time to froust — it might become a habit — so, having recovered from discovering the strange cephalopod carved into what was purportedly the Maize Maze behind a children's play area in Fulbourn, I planned a route through Cherry Hinton to Fulbourn, Balsham and Little Abington, and thence to the Gog Magog Hills, where various people were flying kites.

Some inconsiderate deity had added a number of hills between Fulbourn and Balsham — I suppose in retrospect that the name 'Gog Magog Hills' might have provided a hint — so this was rather more energetic than I'd expected. Flying a tame and well-behaved kite is surprisingly meditative; you stare up at this little square in the sky, and tug one hand to turn it one way, the other to turn it the other. With the wind as it was on Monday, the tame kite sits of its own accord, mildly exercising your shoulders.

Some people had brought rather wilder kites: click on the photo below for more pictures, and for the flock of geese which it is moderately alarming to find in the road after a blind corner descending a steep hill.