Sun-In-A-Bottle..

I've just finished reading Charles Seife's entertaining book
"Sun in a Bottle" - about the controversial & so-far-fruitless attempts to harness the power of nuclear fusion in a reactor (as opposed to the Hydrogen Bomb).

There are reviews here, here & here.

The strangest part of the hydrogen (well, Deuterium actually) fusion story is that it IS actually possible to construct a table-top reactor!

These should not to be confused with various spurious claims of cold fusion.
(Yes, as i've said before, i DO use Wikipedia - it's a good jumping-off point)

I kid you not! The problem, of course, is their tiny, tiny yield of neutrons, & the fact that - inescapably it seems - they consume far more energy than ever comes back out of them in any useful form.

Confining a super-hot, high-pressure nuclear fusion plasma is like trying to nail jelly to a tree!

Various enormously energy-hungry (& stupendously expensive) devices, like the Russian tokamak (pics,pics,thingies,moreThingies), gigantic magnetic 'bottles', 'pinch' machines, & the international project ITER, have all run into the same problem - it takes so much energy even to try to stabilize the mercurial & leaky 'heavy' hydrogen plasma at the kind of temperatures & pressures needed to sustain nuclear fusion, that their net output is less than zero!!

The 'table-top' machines (here & here) are ingenious, & (as Seife himself says) could even be an economical source of neutrons for, say, neutron-scanning substitutes for X-ray machines.
I thought they were really clever. And they're astonishingly simple, compared to the high-tech behemoths that were constructed for the 'positive-net-output' outcome which, according to Seife, is as far off as ever.

I'm wondering if a bigger 'flood-of-neutrons' table-top machine could be used to tickle up a less-than-critical-mass nuclear reactor to the point where it would run despite its small size..

That would be interesting..

A horrible, horrible car (& other musings)..

I got my licence in a 1958 Mercedes - lovely car with a very tolerant owner (I drove over a traffic island on John Wilson Memorial Drive on my first attempt at night-driving). I discovered a couple of other things:
* drinking makes you inattentive
* power brakes are essential (not universal back in the day!)
* seat-belts are essential - use 'em!
* distracting/ed drivers are dangerous!
etcetera etcetera..

Then i climbed into my sisters Phase III Vanguard..
..& got the shock of my life!!
Arrrgghh!!
How could a car be soooo BAD??!!

The bodywork was the least of my problems;
* the boot needed a bungy cord to keep it shut
* the doors sagged & wouldn't shut without slamming
* things rattled (it WAS old-ish, of course)
But the running (& stopping!) gear scared the crap out of me.
* the hand-brake would stop you on the flat - just..
* the brakes (non-power-assisted) were feeble
* the suspension made everything judder at its top speed of about 60mph (95kph)
* 2nd gear seemed to be missing (as in 'never ever there' not as in 'not working')
* the gear-shift was a column-change - which i will now proceed to explain:

Back in the days before Automatic Transmissions became the convenience-du-jour, there was the Column-Shift: the gear-shift was mounted (via a complicated set of inter-linkages) on the steering column.
The 58 Merc had a lovely (German!) 4-speed column shift that worked beautifully,
but on the Vanguard..
..as i said, it seemed to be missing 2nd gear for a kick-off.
Low gear was SO low you could (& my brother did once!) drag off a V8 - for about 20 metres until they caught up with you,
but there seemed to be a yawning revs gap until 2nd!!
This wasn't helped by the clunky, rattly, hopelessly-worn column shift that dithered & rattled whenever you pushed it across the gate looking for a gear on the other side!
And you couldn't get it into gear until it stopped rattling!
Which took an alarmingly long time - like about 2000 revs, it seemed to me.
So, going up a decent hill meant revving like crazy,
TRYING to change up from 1st into 2nd,
& nearly stalling the damned thing from loss of revs.
You had to tickle the clutch while waiting at traffic lights on a hill coz the hand-brake was made of chewing-gum.

There was one good thing - its ex-Massey-Fergusson tractor motor. Tow anything!

Still, i've had custody of more eccentric vehicles..
.. a 1951 Singer: overhead cam, no less (in those days!!) but {sigh}
a very very strange gear-shift made of rods AND a cable!
Which strreeeetched!!
Until it was no longer possible to get it into 1st or Reverse.
Driving this thing was an exercise in timing whenever i approached an intersection where i might have to give way - i could not stop!!
At least, not with any hope of getting started again any time soon..

Did i mention that the exhaust eventually fell off?
As well..

My old next-door neighbour - the bloke with the garage & the belt-driven 3-phase electric power-train - had some disparaging things to say to his two sons about column-shifts, in his classic Coronation-Street accent that he'd never bothered to lose..
"Waste of time! ..fourteen or fifteen moving parts.. a couple of 'thou'(sandths of an inch) off each one.. " .. & so on & so on.. ending with the definitve statement:

"Only proper place for gear shift is on top of gear-box!!!"

And - as we all now know - he was absolutely right!
That's where you almost invariably find it.
On top of the gear-box, where it belongs.

And the ultra-modern, 'flappy-paddle' gear-shifts don't work properly either, at least not according to "Top Gear" presenter Jezza Clarkson - he hates them.
They're too slow for someone used to doing 'racing-changes'..

Finally, the most eccentric car i've ever seen: a post-World-War-2 Auto-Union
(now Audi). It had:
* 3 cylinders operating in 2-stroke mode
* a saddle-back radiator (water-cooled) astride the gear-box
* front-wheel-drive (most uncommon in those days)
* a super-charger
* the Citroen/Volkswagen motor-differential-gearbox arrangement..

..& it went like stink!!
Until it ran into a tree & karked itself..