“The greatest puzzle is a single sheet of blank paper and a few moments. One can fold it, tear it or just ponder its fearful opportunity.”
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October 2013 - Memories of “Martin's First Big CR-APP”, the 2013 Croatian Annual Puzzle Party, held in the Croatian city of Split, on the Adriatic coast during October 2013. Including puzzle-hunting through a minefield. Such dedication.
July 22nd 2013 - A formal bulletin confirming that the Duchess of Cambridge has given birth to a baby boy has been displayed on an easel at Buckingham Palace. The message, signed by key medical staff, was taken by a royal aide from St Mary's Hospital in Paddington where the baby was born The presentation of a note, confirming the gender of the child, has been a long-standing tradition for royal births. A puzzle for a long time... My congratulations to the royal couple...
26th June 2013 - If you had a cooking-vessel, shaped like a duck, and then you burnt it, then dropped it, it would instantly change from a pochard to a pot, charred to a potsherd. Try it and see.
AND FINALLY, I am currently really enjoying “L-tetromino + 1”, an IPP exchange puzzle from Tetsuro Kawahara in Prague in 2006, designed by Katsuyoshi Nakahara, and manufactured to their usual high standard by Hikimi. It’s pictured here in The Jerry Slocum Mechanical Puzzle Collection. It comprises a 5x4x1 unit tray and 8 half-thickness L-tetrominoes. Each piece is modified by the addition of a half-thickness cube to each square of (both sides of) the tetromino. The bottom layer of tetrominoes must have 4 suitably-placed voids to take the additions from the top layer. Quite why it’s taken me seven years to tackle it I know not, but it might well take me that long again to find the sole solution.
21st June 2013 - Greetings, pentominophiles, (zero hits on Google today, check it again in a week or two! UPDATE - 5 days later ‘pentominophiles’ gets just one hit, this page, on Google. Are there any pentominophobes around? Google and I will do the same for you!))
I’m feeling trivial today. Possibly it’s a strange question, but do you have a favourite pentomino, or a least favourite? If you have, do let me know and I will add the more interesting choices and reasons here. Perhaps one of them resembles the initial of someone close. Perhaps one reminds you of a place, maybe a holiday island or a feature on a map? I’ve loved pentominoes since before I was a teenager, and if I was to be cast away on that famous desert island with just one toy, out of all my puzzles, I would choose a set of pentominoes. Their possibilities are endless. I could stack them to help me climb a coconut tree, or stand them sturdily on the beach to protect me from high water, or barricade the entrance to my cave to protect me from wild creatures. (My best set is quite large...). I could embed them in the ground in a circle, like a mathematician’s version of Stonehenge. (It is the summer solstice today, after all!)
One puzzle friend hates the ‘P’ pentomino, on the grounds that it is the only one to incorporate a 2x2 square. He hates it with a vengeance, too, as if this unique character trait is a flaw in the design. Maybe you like the elegance of the ‘I’ or straight pentomino, or maybe you dislike it for being too bland and uninteresting? Is your bete noir the ‘W’ because it always seems to be the one that won’t fit, and never seems to know in which direction it wants to go? Do you love the 4-way rotational symmetry of the ‘X’, unique amongst its colleagues? Does your ‘number one’ make the best tiling design? Is the ‘Z’ the one that you always try to place last?
My choice? It has to be the ‘F’. It was the favourite of my late friend Fred, being his initial. I love how it enthusiastically tries, but fails, to cover a 3x3 square on its own, reaching out every which way. It seems to be the rebel of the bunch, carefully eschewing all forms of symmetry, a talent that makes it appear so very different, from which ever angle you view it, even backwards or upside down. I’ll be writing an ode to the ‘F’’ pentomino, if I go on like this... Send me your thoughts, or at least the ones you don’t need anymore.
12th June 2013 - I recently picked up a copy of The Standard, London’s free evening paper. I came a cross a new kind of word puzzle, so I thought I’d spread that word here, and review the puzzle. It’s called GOGEN, and all you have to do is fill the 5x5 grid on the right with the remaining letters of the alphabet. (The angel said ‘no Z’.)
Oh, yes, you also have to make sure that you can trace out the following words in the grid, moving once space at a time in any direction, like a chess king. FORAY - HYRAX - JOBS - LENT - PROD - QUANGO - SCORE - SKIMPY - VERB - WANTED. Then provide the three letters in the shaded circles, reading from left to right.
It wasn’t a really hard puzzle, but I did manage to solve it before reaching my station. I liked it and it seemed a good alternative to Sudoku. The small grid is a bit unforgiving after a few crossings-out. The inventor/compiler is uncredited. Look out for The Standard if you like this idea.
6th June 2013 - The latest puzzle auction is underway at Cubic Dissections.
9th May 2013 - New materials quickly get used in the making of puzzles, (think back to plastic, ABS, tear-resistant card and 3D printers). Two new materials are Sugru and Graphene. How soon before we see them being used?
8th May 2013 - Above and below are a selection of wotsits, which are unusual or interesting objects whose purpose is not immediately obvious. Perhaps we should call them Welsh Assemblies? I particularly welcome suggestions about the first item above, as I really don’t know what it is for (let me know). The scribble below is not toilet humour, it was instructions from my GP several years ago before an operation. It actually says “Fasting - solids.”
1st May 2013 - During a sort-out and puzzle reclassification this morning, I came across a slip of paper, author unknown, bearing the following cryptic text,
“Cache, tether, trough, slaughter, and my best, auntie.”
I don’t know who gave it to me a long time ago, but if you know, I’ll give you a mention. Its content made me smile, so if you can add to it, let me know.
Silly thought: I had the idea of the following advert:
"For sale, Scrabble set, unfortunately the following tiles are missing, a,e,e,h,n,r,w,y.
They could be ANYWHERE."
It made me laugh...
29th April 2013 - I’ve added a long and slightly tongue-in-cheek look back at over 40 years of my puzzle-collecting and love of maths. I’ll probably add bits to it when forgotten events come to mind.
27th April 2013 - Have a quick look at the truly stunning close-up pictures of pollen on this link, a sort of ‘site for sore eyes...’. Some of them look so mathematical, almost like 3D puzzles, but certainly not to be sniffed at!!
On yet another different subject, I don’t normally play computer games, but an annoying friend sent me this link to a game where you have to quickly pinpoint European cities on progressively less-detailed maps, in a short time. I scored 23,190 and realised that I’d forgotten the locations of some previous International Puzzle Parties...Only your first score counts, as there are some repetitions after a while.
17th April 2013 - It’s apparently approximately Archimedes’ 2,300th birthday. Celebrate and find out what you don’t know about levers, hydrostatics and getting out of the bath earlier than you planned, in this article.
16th April 2013 - Alice and I have such wonderful memories of our two visits two Boston, MA, firstly in 2003 for a week before the Chicago IPP, and again in 2006 for the Boston IPP at Logan Airport. It is so sad to see the pictures in the press today following the bombs during the Marathon yesterday.
I remember sitting near the front of a small aircraft at Logan for the short flight to Chicago, after a wonderful week walking round Boston. The captain opened the door to the flight-deck and suddenly played a jaunty tune on his harmonica before take-off. I remember endless walks across Boston Common, sitting in the bleachers watching baseball when we needed a rest from the Heritage Trail. It should have taken an afternoon, but we did it in such detail that it took days... I remember walking along the river from Brookline to Downtown, I remember sitting on the quayside at the end of each day’s exploring. I remember drifting in a swan boat. I also remember falling over and badly bruising myself while running for shelter in the rain. I remember walking to Cambridge and around the Harvard campus, then being given a promotional frisbee as we walked through the grounds of MIT. (I’ve joked ever since that I actually studied aerodynamics at MIT for five minutes!) I remember our group visit to the Maize Maze, and witch-hunting in Salem.
Our sympathy goes to all Bostonians at this sad time, and especially to our many puzzle friends from across all of Massachusetts.
13th April 2013- Left, from my friend Matti (Thank you so much!!) a set of Finnish tangram puzzle stamps, which arrived with out the PO obliterating them.
11th April 2013- I strongly recommend this BBC article and 5 minute film about someone who makes interesting objects from old scrap, such as a three-quarter ton corkscrew.
March 28th 2013 - Have you noticed how I sometimes add a new entry further down the page...?
March 24th 2013 - I will shortly be selling a Braille Crossword Puzzle Outfit on eBay. I have had this in my collection for many years, but can’t remember where it came from. It is produced by the Royal National Institute for the Blind, catalogue No. 9097. I have no idea how old it is. It is in good condition, and is made from wood, rubber and plastic. Pictures below, let me know if you have any questions or want more pictures. Start price will be £9.99.
We all struggle with puzzles to different degrees, but imagine how much harder they would be if you were solving them by touch alone. I thought I’d mention the Braille Bookstore which sells some puzzles considered particularly suitable for blind people, including a Braille sliding puzzle.
March 20th 2013 - While 3D printers aren’t yet as common as microwave ovens in the kitchen, or DVD recorders in the bathroom, they are becoming increasingly available and affordable. Apparently the technology is also known as additive manufacturing - who thinks up these names..? My favourite IT gossip column has an interesting report on their future. Read it now and make a diary entry to read it again on March 20th 2015 as part of your nostalgia. Another good related article is this one about the 3D Doodler pen. Now, shall I recreate Johannes Gutenburg’s printing press or a life-size Oskar Van Deventer...?
March 17th 2013 - I was thinking about asking which puzzle in your collection would you most like to have the courage to dismantle. Instead I turned it back on myself and came up with the one to the right. It’s nominally a 22-cylindrical-piece burr. If Gandalf had designed puzzles, I think one of his would look like this. I probably bought it in Amsterdam in the mid-1990s. To me, it looks like some kind of exotic fantasy flying ship. I’ve got other burrs with cylindrical pieces. I’ve got one such 6-piece burr that is designed so that the pieces in each pair don’t actually line up with each other, from Polzeath Puzzles. Very tricky, (nearly as hard as finding Polzeath). This one has the added confusion caused by the ‘fake’ notches that look like ‘sails’ on the ‘masts’. There is a blank key piece, the middle stick on the top row of the six short lateral rods. Once that is released the tallest ‘mast’ lifts out.
Then the horizontal one towards the back left in the picture comes out. Then I put them all back in again...
March 15th 2013 - Let’s consider chitmohols, always a good word to use when playing Bangladeshi Scrabble. Recently I've been reviewing mapping and GPS apps for my new Nexus 7 tablet computer. I'm looking for the best one for maps available offline. Totally randomly I installed the map of Mali, being topical, and also to have a look at Timbuktu, a name which still conjures images of mysticism and the African exotic. I think that generally, until DJ Andy Kershaw popularised the country's musicians, very little was know about the place. Anyway, digressions... I then followed the coastline of West Africa southwards towards Angola, and came across a relatively small area of land (well, 3,000 square miles) which didn't have a country name. (We WILL get back to puzzles shortly...) Eventually I became aware that just south of the bulge of West Africa, bordering on both Congo and the Democratic Republic of the Congo (thet are different countries), just west of Kinshasa, these is an area called Cabinda. Cabinda is an exclave which belongs to Angola. We all know about enclaves such as the Principality of the Valleys of Andorra (its capital is the highest capital in Europe) and San Marino (especially since England's football team beat the latter 8-0 last week) where a country is entirely surrounded by another larger one. Well, exclaves are pieces of land that belong to a country, but aren't contiguous with that country.
I then clicked on a link to find out more about exclaves. We now, at least briefly, return to puzzles. Most readers here will know about the one where you have a pint of tea and a pint of coffee. You then transfer a cup of tea from the tea container to the coffee container, mix well then transfer a cupful from the coffee container back to the tea container. The puzzler then has to deduce whether there is more tea in coffee, or vice versa. Well, now back to exclaves. There are places around the world where, either side of a shared border, there are small areas which belong to the other country, One such example is on the Netherlands-Belgium border, Baarle, famous for its firework shops.
Now, building up to a big finish, we come to the disputed border between India and Bangladesh. On each side of the border there are exclaves known as chitmohols or chitmahals, of the other country. However it gets more confusing because some of those exclaves contain enclaves belonging to the 'parent' country. Finally, (you couldn't make this up...!), but a so-called third-order enclave exists, named Dahala Khagrabari, a piece of India within Bangladesh, within India, within Bangladesh. It is less than 7000 square meters, or 1.7 acres, in size and was the site of a jute field. It is the world's only third-order enclave. (If any puzzler from around the world wants to beat this with a mutual swapping of bits of back garden, let me know.) This brings us nicely back to puzzles and the 4-colour map theorem...
For the exclave fan, I recommend this Wikipedia article, which lists them all and even covers temporary exclaves, a fascinating subject on their own...
March 10th 2013 - Many years ago as a boy puzzler (in my thirties...) I conceived a set of puzzle pieces which could be used to make several different 3x3x3 cube assemblies. The eight pieces comprised the planar pentacubes which could fit inside such a cube. These are shown in the picture below, along with a di-cube, to make 27 units. Each puzzle consists of various 5-piece subsets of the eight, plus the di-cube. Seventeen different subsets can be used to create puzzles with between one and six solutions. This set of puzzle pieces was documented by Kevin Holmes and Rik van Grol in their self-published book ‘A Compendium of Cube-Assembly Puzzles using Polycube Shapes’. It was also recorded here at Puzzles Will Be Played. The 17 puzzles have a total of 43 solutions.
Just recently I have tried to solve each set, starting with the set with 6 solutions, which was fairly simple. I’ve only been looking for a single solution from each set. It’s been fascinating to see just how difficult these puzzles are as the number of solutions decreases. Currently I only have one set left to solve, with just a single solution. Of the four sets with just a single solution, I solved one set very quickly. Was that just luck? I am surprised how long the last set is taking, it’s costing me a fortune in beer. I won’t say which set it is, but I’d like to hear any comments on these puzzles, or on relative puzzle difficulty in general. I wonder whether my ‘nemesis set’ is equally challenging for others.
Those pieces over there on the right are assembled from LiveCubes.
(No sheep was injured in the making of this puzzle...)
Which is the most awkward piece to place? (If you think it’s the di-cube...) What is awkwardness? The F-T-V-W-X-Z pieces all fit in a 3x3 square and can only be placed as an outside face or in the central slice. P and U pieces each fit in a 2x3 rectangle and can each be placed in two positions on an outside face or in the central slice. T-U-V-W all have lateral symmetry. Z has 180-degree rotational symmetry and X has 90-degree rotational symmetry. F-P are not symmetrical. Any placing of two pieces which leaves a 1, 3 or 4 unit void is clearly insoluble.
Rather than just flailing around randomly I started looking at how many different ways any two pieces can be placed in a 3x3x3 cube. It increases quickly! After thinking about this for a while, and adding a third piece, I continued flailing around randomly. Do you solve this sort of puzzle logically trying all permuations, intuitively or by using the flailing around randomly method?
March 4th 2013 - I recently came across this ghost on the internet, a remnant of my first puzzle web site, from about 1998, in the days when I was able to list my collection. The columns, left to right, are name, puzzle type, whether solved, source, my location, and description.
March 2nd 2013 - I’ve recently devised an amusement using a set of 12 planar pentacubes. I call it “Pentacube Pile Up”, because basically you ... pile pentacubes up. The object of the puzzle game is to score more points than your opponents, or more than your previous best score if you play it as a puzzle for one. It will help develop social skills (unless you play alone...), basic numeracy, motor skills and spatial awareness.
Players take it in turns to place a planar pentacube onto the playing surface. The first two pieces are placed flat on the surface, touching each other corner to corner in a rectilinear fashion. Play continues with each player in turn adding a pentacube at any level above the first two played. For each horizontal unit square under your just-played piece that touches a previous unit square, you score one point. For each vertical unit square that touches a previous unit square, you score two points. Play continues until all 12 pieces have been played. The player with the highest number of points wins. Full rules are here. Below is a finished game of “Pentacube Pile Up”.
March 1st 2013 - As a life-long lover of long words I’ve always been amused by the word ‘metagrobologist’, used to identify a puzzle collector, or one interested in puzzling things. I’ll even confess to owning a shirt inscribed “Let me through, I’m a metagrobologist”. This concept is taken very much further by the people at HORG, known formally as The Holotypic Occlupanid Research Group : A Database of Synthetic Taxonomy. As they put it on their home page, “This site contains several years of research in the classification of occlupanids. These small objects are everywhere, dotting supermarket aisles and sidewalks with an impressive array of form and color. The Holotypic Occlupanid Research Group has taken on the mantle of classifying this most common, yet most puzzling, member of phylum Plasticae.
February 28th 2013 - I doubt any readers here won’t be familiar with the 3x3x3 puzzle called the Soma Cube. It comprises the seven simplest non-rectilinear pieces made from gluing 3 or 4 cubes whole face to face. The piece made from 3 cubes is L-shaped. There are 240 different ways of fitting the pieces into a cube excluding reflections and rotations, as you are probably aware. A friend mentioned something which made me check with BurrTools to see how many solutions there would be if the L tromino was replaced with a straight one. The answer was 138, considerably fewer. This got me to thinking, does that mean that the puzzle would be harder with a straight tromino because there are fewer solutions? Or harder to find all the solutions? Or easier because it’s a simpler shape? Let me know your thoughts.
February 27th 2013 - Here’s a real-life version of one one of those irritating maths problems that you used to get in school. They usually came up just when you’d rather have been playing with the pentominoes or dipping the pig-tails of the girl in front into your ink-well. I was in a local grocery shop and saw that some items were on special offer, three for the price of two. (They were actually bags of bread flour, and recently I’ve spent as much time making home-made bread in my new breadmaker and growing bamboo as playing with puzzles, but they’re two other stories.) The flour is usually £1.99 a bag. Now if you’ve followed me this far, you’ll realise that if they are three for the price of two, then three bags will cost you two times £1.99, or £3.98. (Do keep up at the backi!!!!) Also on the same ‘three for the price of two’ offer were some smaller bags, at 99p each. Three for the price of two would cost £1.98. So, I merrily put three large bags and three small bags into my basket. Now most of you will have worked out that my basket of six bags of flour is going to cost me £3.98 plus £1.98, that’s £5.96, rather than the full price of £8.94, so you will understand my surprise when it actually came to £6.96. I don’t know how many non-puzzlers would have realised this, but on the shelf near the offer was the statement, “Three for the price of two, cheapest item free”. What those wicked people had done was give me two of the small bags free, rather than one big one and one small one. Isn’t that the meanest, sneakiest trick? Luckily, the tills were quiet, so I paid for the three large bags, getting one large bag free, and then paid separately for three small bags and got one small bag free. You’ll remember this story next time you see a similar special offer, won’t you?
February 26th 2013 - BurrTools (BT) is the pre-eminent software tool for solving and helping design puzzles such as cube assemblies, checkerboard puzzles, burrs and complex interlocking designs. It is available for free here, along with extensive documentation. It is so fully-featured that it appears quite daunting at first, so I have written the following tutorial which covers the basic creation of a puzzle. I’ve used Piet Hein’s Soma Cube as an example, as it will be familiar to anyone with an interest in its use. It will familiarise you very quickly with many of the controls, before you move on to the full manual. It’s so very sophisticated and highly functional that it deterred me for a long time. This tutorial will give a fast introduction to its use.
February 22nd 2013 - I had a bizarre and very unlikely occurrence last night after a heavy game of Blokus. If you don’t know it, up to 4 players have to place pentominoes and smaller polyshapes onto a large grid, fighting each other to control space. After the game, without realising my camera was set to monochrome, I took a photo of the final board position. Unbelievably, the QR Code scanner on my new Nexus 7 tablet identified the board as a valid code, and amazingly, connected me to my own website. What are the chances of that happening?
February 19th 2013 - I recently watched ‘National Treasure - The Book of Secrets’ starring Nicholas Cage. It’s a highly-unlikely treasure-hunting tale, which involves our hero, and his co-star the lovely Diane Kruger solving numerous puzzles, including opening secret drawers in matching antique tables in Buckingham Palace and the White House. It’s very much in the style of H. Rider Haggard (like Indiana Jones then...), culminating in the discovery that a very famous place is actually a secret-opening monument, trap and labyrinth in one. The book in the title also includes the answers to many mysteries of American history. I’ve given nothing away, and the most impossible bit is the car chase through London, along roads that just aren’t anywhere near each other... The best line is “There are no more puzzles - we’re all going to die.”
February 7th 2013 - I came across one of these, below. It’s called Cir*Kis, from Hasbro, but I don’t think it ever caught on when released in 2009. It was recently being remaindered at Amazon. It’s a game for 4 players, but fun to play with alone, using kites and darts to make shapes. It’s about 12 inches across. It’s interesting, because there are 4 sets of about 15 pieces each of 4 colours, but the board has 5-way rotational symmetry.
February 7th 2013 - After several months of covetousness I bought a 32Gb Google Nexus 7 tablet. More about my experiences with it here. Having worked in IT for most of my life, it takes something rather special to impress me technologically, but this gadget is stunning. I’ve never been a fan of computer games, preferring real puzzles that you can accidentally drop, but I have now realised that there are some excellent brain games available for computers, often ideas that couldn’t be realised as physical puzzles. If you have a phone or tablet that runs the Android operating system I recommend some of my favourites here, all available from the Google Shop. It’s quite a long review article so it’s got it’s own page.
February 1st 2013 - Starting on Sunday 3rd, open for viewing now at Cubic Dissection, I am auctioning two Akio Kamei Karakuri Puzzle boxes, Star Box and Twin Ball. The auction runs until 10th February. Visit Cubic Dissection for pictures, and your bank for funds... If you haven’t already got one, someone is auctioning my Watson’s-Trilateral-Windowed-Hexahedron puzzle.
January 31st 2013 - I was recently sorting through a box of puzzle papers from about 15 years ago. Amongst them I found a printout as seen below. Instructions are along the lower edge, but ignore the words ‘or horizontally’. Push the coins, like in Sokoban. Click the picture for a larger view.
I think I created this sheet, based on a Java application, Binky, I found on the internet. At the time I didn't have a Java-enabled PC, so I tried to play this as a game on the sheet.
I just wondered if you had ever seen this before, or if you know who designed it, or if there is still a URL to the game? I searched for the text without any luck. I probably edited it slightly for UK coins.
It is a very good and infuriating puzzle, and if I am unable to find a designer for it, I will make this layout available for printing, mentioning that it isn't mine. You need to use every single one of the pennies, very carefully. I have solved it, but it took a while. Contact me.
ALSO in the same box I found the wrapper from a puzzle called ‘Plait Puzzle’ by ‘Rising Sun’. The text says “The aim is simply to untangle the rope so that there are just four straight pieces connecting the two blocks of wood. The rope may be moved over the wood, or the wood through the rope, it’s up to you. The rope may be tangled again upon completion to a harder or easier starting point.” Do you have this puzzle? I don’t know where the wrapper came from as I don’t have this puzzle. I’d like a picture. Contact me.
January 20th 2013 - I am currently reading a book of Edgar Allan Poe’s short stories. Anyone reading here is likely to enjoy ‘The Gold-Bug’, a tale of cyphers, pirates, codes, trigonometry and buried treasure. You’ll learn the meaning of this text
Dave tells me he thinks that Count Me In is a better name than Digigrams. I disagree - what do you say? Contact me. It was an exchange puzzle at the 2000 International Puzzle Party In Tokyo, by the way. Fit the digits into the tray to form a lattice pattern. Read about how I created it here.
October 2012 - A few mathematical, Celtic and puzzling images from Dublin during Maths Week.
Left, a giant circuit board in the window of ‘MAKESHOP’, a new collaborative workshop space where you can learn everything from DIY robotics to 3D printing.
Right, an unusual (aren’t they all?) trompe l’oeil, purpose unknown.
I thought that this was rather special, and quite easy to miss, as it is only 55 yards across! It’s the helipad in the Peace Garden in the grounds of Dublin Castle. (“Gentlemen, you can’t fight in here, this is the War Room.” (- “Dr Strangelove” reference)). It consists of 6 identical (at least to us topologists...) snakes, 140 yards long, forming a Celtic-style pattern of paths, about nine inches wide. From the head of any snake, you walk in a sort of fish-shape, then almost across the diameter of the helipad, before a final loop takes you almost back to the edge. Photo from Google Earth. My terrestrial ones are just below.
Left & right, my pictures of the ‘Celtic’ helipad at the castle. I did spend a ridiculous amount of time meandering along these charming paths.
Left, patios for the mathematician?
Right, a new puzzle ball perhaps? Watch the video below and decide.
I was going to add pictures here of this object as soon as I saw it, but I decided it deserved a bit of YouTube too. It’s in the grounds of Trinity College Dublin.
Two more odd spheres, left, on a pole 10 feet high, about 6 feet in diameter, which we passed in Dane Street,
...and a sphere of padlocks, right, in the Revenue Mueum at Dublin Castle. Two feet diameter.
Above, and left, tessellations from Christ Church. The ones on the left look like buried Rubik’s cubes.
Below, through the window of ‘The Yeast Shop’, a quaint cake shop. Why these are on the wall is a mystery.
Left, a close-up of a very large girder in the Guinness Brewery, and right, some of the kit on the roof seen from the 7th floor tasting room.
Yet another interesting sphere from Dublin, fair city. This one has an internal flame burning inside it, but it wasn’t adequately eternal today.
That’s all from this mathematical look at Dublin.
6th October 2012 - Try not to look too closely at the bottom right corner of this while you ponder on its use.
Fascinating idea, this wotsit, but I can’t really see them catching on. It’s flat, about 24 inches by 18. The ‘white’ holes come free as standard.
24th September 2012 - The Collective is a fiendishly difficult 29-piece burr. Here is the story of my recent attempt to solve it. I don’t come out of it looking good...
17th September 2012 - I’ve been meaning to add the following Radio Times listing for some time. If the 1.40 entry needs any explanation, don’t ask.
September 2nd, 2012 - While exploring the alleys of the City of London with Alice, we came across these very interesting mathematical tilings, below, by Rupert Spira, just south east of the end of Fleet Street, in Waithman Street. (Robert Waithman, in 1823, was elected Lord Mayor of London.) Each of the 20-odd panels is about six feet square.
August 1st 2012 - I've been meaning to try creating a YouTube film of me talking about some puzzles for a long time. This is my first attempt, totally unscripted. It's not easy. It's surprisingly difficult to talk, watch and focus the camera screen, dismantle puzzles, and have the next one lined up, all at once. Don't knock it until you've tried it. Nice comments will encourage me to do more of these, choosing more interesting items, rather than just the first ones I picked up. I don’t have the time to write a script first. Too many puzzles... I’ve had the decency to realise that I’m not a TV presenter, so this film shows me from the elbows down! And yes, the purple puzzle is one piece short!