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Eunoia, who is a grumpy, overeducated, facetious, multilingual ex-pat Scot, blatantly opinionated, old (1944-vintage), amateur cryptologist, computer consultant, atheist, flying instructor, bulldog-lover, Beetle-driver, textbook-writer, long-distance biker, geocacher and blogger living in the foothills south of the northern German plains. Not too shy to reveal his true name or even whereabouts, he blogs his opinions, and humour and rants irregularly. Stubbornly he clings to his beliefs, e.g. that Faith does not give answers, it only prevents you doing any goddamn questioning. You are as atheist as he is. When you understand why you don't believe in all the other gods, you will know why he does not believe in yours :-) Oh, and he also has a neat English Bulldog bitch 'Frieda'.

And her big son 'Kosmo'.

Some of my bikes

My Crypto Pages

My Maths Pages

Friday, November 27, 2015


Yesterday the USA was celebrating Thanksgiving. As part of the celebration the US President, not unexpectedly, pardoned Turkey.

Comments (1)
Doug (Canada) sent this link to a rather paranoid US article.

Wednesday, November 25, 2015

In Memoriam : Albert Einstein

Today we celebrate the centenary of the publication of Einstein's theory of General Relativity. Here's his Swiss passport :-

Einstein fled Nazi Germany in 1933, handing in his German passport at their embassy in Brussels. He emigrated to the USA (as a refugee, which various state governors there might like to note), swearing never to return to German soil. However, it is a little known fact that, when visiting his mentally ill son in Zurich (Switzerland) in 1952, he had a driver take him incognito to Büdingen (in the state of Hessen, Germany) to visit friends there :-)

General relativity postulates that mass (gravity) distorts space. Within a year of Einstein's 1915 paper an expedition set out to a location on the line of totality of an eclipse of the sun to measure the apparent angle of the stars. This is shown in my sketch below which is NOT TO SCALE.

Before the eclipse, the sun is at position S2, the earth at E, and a star A which is due to disappear behind the sun during the eclipse appears to be on the line AE. During the eclipse, the sun is at position S1 and the moon is between S1 and Earth E, so the observers are not blinded by the sun, thanks to the total eclipse. Photographs showed that the same star now appeared to be at position B, having "moved" by an apparent angle C. The thick black lines show the path taken by the star's light rays. With the sun at S2, the starlight travels along the straight line AE. With the sun at S1 during the total eclipse the rays are bent by gravity along the curved black line AE, so the star appears to be at point B. These measurements were taken for several stars in the photograph. The apparent angles C were all in agreement with Einstein's calculations and the theory of General Relativity was confirmed :-)

I shall not repeat last week's mistake of reproducing his calculations; instead I'll quote to you three of my favourite sayings of his :-

  • "The deeper we penetrate and the more extensive and embracing our theories become, the less empirical knowledge is needed to determine those theories."

  • "One has been endowed with just enough intelligence to be able to see clearly how utterly inadequate that intelligence is when confronted with what exists. If such humility could be conveyed to everybody, the world of human activities would be more appealing."

  • "It is a mistake often made in this country (USA) to measure things by the amount of money they cost."

Comments (2)
Carol (UK) asks "How wide is the path of totality?" About the same size as London (i.e. M25 orbital motorway).
Norbert (D) wrote " Coming out of the Institute one day, Kemeny and Einstein met von Neumann. "You have made the wrong kind of computer," Einstein told von Neumann. "Why don't you invent a computer that would help me in my work? I don't need a numerical computer:" Nice quotation; but nowadays of course we have computers with symbolic maths SW packages (e.g. algebra and calculus). I recommend Wolfram Alpha, usable even via your smart phone!

Monday, November 23, 2015

Driving School Roof

Riding my trusty motorcycle through the village of Niederntudorf the other day, I noticed the village driving school has a neat slate roof.

The owner had the roofer make an image of his Porsche 911 out of slates. Very identifiable as a 911 and probably unique. How cool is that, then :-) Here's also the close-up which I stopped and took:-

Comments (1)
Hattie (Hawaii) wrote " Cool roof. I wonder if that is an original idea of his. I've never seen anything like it before." Sure is neat :-) My friend Frank is also a master roofer and says that if houseowners provide a sketch, master roofers can make almost any picture out of the slates :-)

Friday, November 20, 2015

Baggage Blooper

The crash of that russian jet in Egypt, due to a bomb on board, reminded me of an incident - way back before 911 - which happened on an airline flight which I once took.

We had all(?) 117 boarded and were seated, the baggage handlers finished loading the hold and - having counted the bags - reported (to the purser) "142 checked bags loaded". Well concealed panic as the purser saw his loading sheet read "141 bags checked". Oh dear :-(

The cabin crew went down the aisle, two stewardesses independently counting the passengers. Yes, both got 117, the same as the number who had checked in. So no suspiciously missing passenger; that was a relief.

So there was an extra bag???

The purser ordered the bags all unloaded again. The baggage handlers lined them up alongside the left of the plane, where - I thought - had there been a remotely triggered bomb, the explosion would have ripped into the plane, destroying it :-(

By now it was raining - a medium drizzle - but the purser called upon all those who had checked baggage to disembark down a rickety and slippery-when-wet push-up staircase. So we did and joined the queue to identify our bags which the baggage handlers then reloaded. If a remotely triggered bomb had gone off, the shrapnel would have wiped out all the passengers, the baggage handlers and the purser too :-(

At the end of this procedure - all the disgruntled and wet passengers having reboarded - there was one bag left on the tarmac! The bomb?

Nowadays, airport security would have whisked it away and had the bomb-disposal squad explode it preemptively in some remote bunker at the edge of the airport. Back then - suicide bombers not being a known phenomenon - the purser had all the passengers look out of the left side windows to see if anyone could identify the bag.

Some bright(?) bimbo then piped up "Oh, that's mine. I just didn't want to go out in the rain because I've just had my hair done" !!!

Multiple booing then ensued with a demand that the stewardesses give the bimbo hemlock instead of coffee with her meal (my own suggestion) ;-)

So it turned out just to have been an initial miscount by the baggage handlers, but I was relieved that such elementary security checks were in place :-)

Apparently not so in Egypt :-(

Wednesday, November 18, 2015

E = m.c2

Back in 1905, 110 years ago TODAY, Albert Einstein published what has become the most widely known equation in the world. He forgot to include it in his first paper on Special Relativity and so published it in a second paper, quasi as an afterthought.

And so, to celebrate this equation, I'll show you how I'd go about deriving it (a little calculus will be necessary, so skip this posting if it gets too hard for you). Excuse my handwritten maths, it's faster scanning paper than me trying to typeset the maths ;-). Einstein's proof was different and longer.

We use Einstein's two postulates : The speed of light is constant, and physical laws are the same in all frames of reference. Now here's my derivation* :-

In the first equation, below, we write the kinetic energy K as the integral of a force F applied over a spatial distance s.

Then we remind ourselves of Newton's second law of motion for the force F. Force is the rate of change of momentum, which we write thus :-

Next we substitute Newton's second law of motion into the kinetic energy integral, then transform from integration over space via integration over momentum to integration over velocity, thus getting :-

Now we can do integration by parts across the velocity integral, getting :-

And by setting the kinetic energy to zero (velocity zero in our frame of reference) we get E = m.c2 :-) Easy, peasy but 110 years too late ;-)

Ah, that was good. Been some time since I flexed my mathematical muscle:)

Comments (5)
Jenny (Ibiza) opined "You make it look so easy. I felt I almost understood. But only almost :-(" Okay, we know maths was never your strong point ;-)
John (UK) wrote "Neat sleight of hand swapping those integrals around!"
Petra (A) asked "Where did the root(1-v^2/c^2) come from?" Pythagoras. It's the Lorentz transformation (1892) which Einstein knew all about. In my derivation above I made sure to use only formulae that Einstein would have known pre-1905. BTW: next week is the centenary of the publication of his General Theory of Relativity (gravity = warped space-time) :-)
Piet (NL) complains "Too highbrow again! You are the only blogger I know who blogs freehand calculus and expects to retain readers :-(" OK, next article will be much simpler :-)
Cop Car (USA) points out that someone beat me to it " You could have saved yourself time (and provided non-freehand calculus for Piet) by going to the website: While there, you could have followed a link to see a picture of the author's house (worth a look at!) I know, I know: you needed the mental exercise. I've not worried about such derivations for a while - probably not since substitute-teaching high school physics in the 1960s. ;-)" Reassuringly, they took the same path :-)

Monday, November 16, 2015

Self-Driving Car got a ticket ;-)

The headline last week which I enjoyed most was Google Self-Driving Car Pulled Over By Police. Apparently, it was driving too slowly and caused an unneccessary backup in traffic. A motorcycle cop "stopped the car". How?

Can the car hear the police siren (N.B: different sounds in different countries)? Does it then pull over?

Can the car see a flashing blue light in the mirror? Does it then pull over and stop or just move over to let the emergency vehicle pass?

Can the car recognised it is being flagged down by the biker cop next to it?

Does the cop have to overtake and then brake to force the car to stop? Can it recognise a police bike/car from the rear? What stops the car then pulling out to overtake the stopped-cop static obstruction? If the cop then tries to shoot the car for trying to escape, where should he aim? What if the car was black?

Whom did the cop ticket? Did he also ticket the car for driving without/ failing to show a licence? Why doesn't the car have a numberplate?

OKay, Okay, I know that in this particular case there was a Google technician on board. So he probably just reverted the car to manual mode and stopped it himself??? But what if the car had been autonomous with nobody on board? What happens then? And WHO (sic!) gets the ticket?

If an autonomous car is involved in a minor accident (maybe just scraping another vehicle) does it stop? If not, who/what gets charged with "fleeing the scene of an accident"? Can the autonomous car lose its right to drive until the software is fixed to cure that? Does this apply to all cars with the same SW?

Inquiring minds want to know :-)

Google, I know you read this, so would you answer these questions please ;-)

Comments (1)
Hattie (Hawaii) wrote " Stu: You are such a fount of knowledge. I like the way you know so much and think things through in a scientific manner. Have you ever speculated on the possibility that driverless cars will start driving themselves around, just for fun?" Not soon. Rule 34 implies that driverless dildos will come first (sic ;-) )

Friday, November 13, 2015

Hawker H25 (PR) disaster in Ohio

Just in time for Friday 13th, a pilot friend mailed me about an aircraft accident (in Akron, Ohio, USA) near his university (Case Western in Cleveland) which took place I guess on tuesday afternoon local time.

It is reported that a Hawker H25 10-seater business jet clipped an overhead wire, causing it to crash into a housing block. As I remember Akron Fulton airport the approach from the SW goes over the Interstate 77 intersection, so it must have been an excessively low approach from the NE where the nearest buildings are about 500 yards from the runway threshhold. Weather conditions were "poor, with low visibility and fog", so it sounds like busted minima to me. Sure, the USA still has overhead power lines and telephone lines, but I think these would have been below the treeline there??? Anyway, the crash site is about 2½ kms from the threshhold, on the extended centerline, so the altitude should have been at least 400ft. It's a LOC/DME approach (i.e. no glideslope) to runway 07, so Minima are at about 500 feet (sic). But just 20 kms or so north is Cleveland-Hopkins International Airport (KCLE) where runway 24 has an ILS (with glideslope) and thus a 200 feet minimal altitude, a much better choice IMHO given that weather. I would have diverted there regardless!

Since I had no mental image of what a Hawker H25 jet looks like, I googled for an image of a "Hawker H25", and this is what Google just gave me:

Just how much of a PR disaster for Hawker is that? From the first 15 images Google returned, only 1 was of an H25 jet and 14 of the crash site and of course no explanation of the reasons for this :-(

So, PR disaster for Google too :-(

Comments (2)
Ed (USA) wrote "The apartment got hit but the occupant survived by eating junk food." Thanks for the heads up.
John (UK) wrote "Sky News in the UK has its own PR disaster today with the awful headline "Terry Wogan pulls out of Children in Need". Oh dear! " He he, that was funny! But now they've replaced it with "Dermot Replaces Wogan On Children In Need" which is much less libelious ;-)

Wednesday, November 11, 2015

Rolling Home

We arrived home from our annual motorcycle tour (High Tatra this year) at 7:06 pm, just 6 minutes late, after completing 4255 kms, visiting 7 countries, accident-free and having had a real adventure.

Here Frank greets his wife Ulrike happily. I'm already planning a tour of Ireland for 2016; Westward Ho! next year :-)

Tour completed :-)

What could have been planned better? As part of the planning phase, I should have checked the opening times of all the places we wanted to visit via their web sites in advance. That would have saved 2 disappointments. Similarly, we should have bought tickets online the day before visiting the more popular attractions. Also my light airflow textile suit trousers split at the seam (see below). Frank thinks this was due to Slovakian beans ;-) But it was due to inferior goods :-( The shop (Polo) refused to replace them as they were 2 months out of guarantee, although only used 8000 miles. Should I have worn my leathers? No, because it got very hot (39°C) on several days. I also got hit on the thigh by a stone thrown up from a truck I was just overtaking (see below). Again leathers could have prevented the bruise.

Also, my backpack was not such a good idea as the Czech minor roads were quite bad. So my spine hurt. Next trip I'll invest in a pair of saddlebags :-)

Comments (2)
Hattie (Hawaii) wrote " It was fun to get up close and personal with a portion of your anatomy. It must be difficult to find things to wear that are durable enough without being too hot. Glad to catch up with you and enjoyed the pix." Looking forward to reading your OZ-trip blog too :-)
Jenny (Ibiza) wrote "It has been interesting to read about your MC tour and see all the photos. Glad you liked it :-)

Monday, November 9, 2015


The last sightseeing stop of our 2015 motorcycle tour was to see the old market town of Schmalkalden, NNW of Suhl. The green corner house on the market square has an oriel window providing an area in which the occupants could peer out and see the activities below and along both side streets while remaining invisible themselves.

Most of the old frame houses had stone ground floors below the wooden frames, an early fire precaution. These are beautifully restored :-)

Across the market square, the Schmalkalden central church has a spiked miniature clock tower added later, probably as an afterthought?

Even the more modern buildings have been built in the old wooden-framed style. That is what I call excellent town planning! Well done, Schmalkalden!

To be completed...

Comments (2)
Schorsch (D) asks "OT: What about that Valencia MotoGP race yesterday then?" Totally unfair and unsporting, but what else would you expect of Marquez? The Honda riders (spaniards) ganged up on the italian Vale (who gave his best effort, starting last and getting to 4th) and by remaining behind Lorenzo (also a spaniard) let him become World Champion instead of Vale. The Hondas were faster in the straights and could have easily overtaken Lorenzo, but then Vale would have won the championship. This was a pre-arranged setup :-( I hope Honda and Dorma fine those 2 riders for being unfair. Damned national politics. The real winner on sunday was Vale; Lorenzo (Yamaha) is only champion by the grace of Marquez und Honda :-( Shame on all three!
Schorsch (D) replied "So what do you suggest?" The sports commission (CAS) should punish the conspirators, e.g. by giving them a 20 second penalty on their race times ;-)

Friday, November 6, 2015

Suhl motorcycle museum

While in Suhl we naturally also visited the motorcycle museum there. It is conveniently right next door to the weapons museum and recognisable by the AWO bike on a pole outside. Simson and AWO bikes were built in Suhl. During the DDR era (East Germany) their most popular AWO model was a 425cc pushrod cardan-drive single; a cutaway of the engine was one of the first things we saw in the museum.

Suhl had been building motorcycles for a while, even before WW2, this is a 1927 Rennsteig, built by Hermann Schilling & Co. It uses a british 350cc SV Blackburne engine in a rigid frame. Acetylene lamp, no electrics.

Post-WW2, AWO also produced a 600cc boxer for sidecar use; it seems to be a copy of the Zundapp Green Elephant made in West Germany.

The other East German make was the MZ, typically two-stroke singles.

Few western bikes were available in East Germany so someone went to the effort of carving a WW2 military Harley out of wood! The performance was probably even worse than the US original ;-) These military Harleys had the throttle on the left so that the rider could fire his rifle with his right hand!

At the other end of the performance spectrum, they had a 1960s era Manx Norton racer, 500cc DOHC single delivering 55 hp to the rear wheel.

Inspired by the Manx Norton's DOHC head, an AWO engineer even developed a DOHC head for the underpowered 425cc AWO Sport. It was not adopted.

To be continued . . .

Wednesday, November 4, 2015

The Weapons Shops of Isher Suhl

On the last day of our 2015 motorcycle tour we made our first stop at the weapons museum in Suhl. Suhl is a town famous for gunmaking. Although the museum is on a main road, there is a large parking lot just across that road. The museum is recognisable by the flag outside and the brass statue of a huntsman on one of the benches by the entrance.

Personally, I also liked the look of the old buildings in which the museum is housed, dating back to the 16th century or so and nicely restored :-)

The exhibits vary from muskets and hunters' decoratively carved guns, to

early WW1 machine guns of the Gatling type, said to be "portable" ;-)

Amongst the pistols I discovered this TOZ 35 single-shot 50 meter target pistol which had belonged to Harald Vollmar, used during the 1964 world championships. I owned one of these during the early 1970s, wooden grip carved to fit my hand exactly, the most accurate pistol I have ever shot, capable of repeatedly hitting a tennis ball at 50 meters. Mind you, Harald Vollmar could repeatedly hit a table tennis ball at the same range :-)

After visiting the museum, we retired to their pub for lunch. Note the opening times on fridays and saturdays, 10 am until 7 am the following morning :-)

BTW, The Weapons Shops of Isher is a sci-fi novel by A.E.Van Vogt about the right to bear arms, well worth reading, even if 65 years old :-)

To be continued . . .

Monday, November 2, 2015

Steam locomotive museum at Neuenmarkt

SStill blogging about our 2015 motorcycle tour :-)

Next day we had a pleasant ride through the hills of the Bavarian forest, occasionally crossing the green border to ride along the Czech side through the Bohemian woods, but the road is much bumpier there :-(

Our first stop was at Germany's steam locomotive museum in Neuenmarkt (Franken). My father worked for British Rail all his life, hence my fascination with steam trains is probably a carry-over from my childhood memories :-)

The sign at the entrance show a class 10 locomotive, indeed the first one. And inside the museum we found the actual 1957 number 10001, converted from coal to oil, parked under a steam extractor hood. This would imply it was still active, but we were told this was not so, although others are.

The museum has about 30 locomotives, some not to be boarded (like 95 016), some showing their internal working (boilers etc), most explained well.

With some, you could climb aboard the footplate and inspect the controls close up :-) On another footplate, the controls there were labelled and explained to the layman. But no, their layouts were not standardised like a car or plane.

Out in the yard were some narrow gauge engines, one being transported via a regular-gauge wagon. Another little shunter was pulling a few wagons around the yard and you could go for a short but nostalgic ride (I preferred the cabrio wagon for the smell etc, next best to riding footplate :-)

Since this was our last night on the road we rode to Kulmbach, a town famous for its beers, to sample a few of the foaming ales. This pint is one of several craft beers from different microbreweries. Delicious, all of them :-)

Next morning, looking for presents to take back to our respective patient wives, we were seduced by the fantastic aroma of these freshly cooked meats

which wafted out of Lauterbach's butcher shop. So instead of buying boxes of chocolates, which would have melted in the sun anyway, we bought presentation boxes of varied sausages and so profited from the idea later too.

To be continued . . .

Recent Writings
In Memoriam : A. Einstein
Driving School Roof
Baggage Blooper
E = m * c-squared
Self-Driving Car ticket
Hawker H25 (PR) disaster
Rolling Home
Suhl motorcycle museum
Gun Museum in Suhl
Steam locomotives
Hitler's house
Chaos of the clocks
Cesky´ Krumlov
Back to the Future Day
Kunovice Aircraft Museum
Banska´ Bystrica

Ain Bulldog Blog
Balloon Juice
Cop Car
Earth-Bound Misfit
Fail Blog
Finding life hard?
Hattie (Hawaii)
Making Light
Mostly Cajun
Murr Brewster
Not Always Right
Observing Hermann
Rants from t'Rookery
Scary Duck
Spork in the drawer
Squatlo Rant
Yellowdog Grannie

Archive 2015:
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Archive 2014:
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This blog is getting really unmanagable, so I've taken the first 12 years' archives offline. My blog, my random decision. Tough shit; YOLO.
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Blog Dewey Decimal Classification : 153
FWIW, 153 is a triangular number, meaning that you can arrange 153 items into an equilateral triangle (with 17 items on a side). It is also one of the six known truncated triangular numbers, because 1 and 15 are triangular numbers as well. It is a hexagonal number, meaning that you can distribute 153 points evenly at the corners and along the sides of a hexagon. It is the smallest 3-narcissistic number. This means it’s the sum of the cubes of its digits. It is the sum of the first five positive factorials. Yup, this is a 153-type blog. QED ;-)
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