This allowed a huge saving of labour, and created a very different shape of mound to the traditional shale bing. Perhaps because the shale was broken to a smaller size and more bound oil was extracted during retorting process, the Westwood bing supports vegetation more readily and have greened much faster than other shale bings. I was skeptical of the house with two rooms for a long time. I just couldn’t see how to squish it up into a point without changing its topology. I took Hatcher’s word for it, but it wasn’t until I made it for myself that I truly believed in its contractibility. The day before spring break last semester, I brought some clay to my topology class, and one of the things we made was the house with two rooms. By the time we were finished, I felt like I truly understood the space. The house with two rooms...and a slightly leaky roof. To build this space, start with a box divided into two chambers by a horizontal rectangle, where by a ‘rectangle’ we mean not just the four edges of a rectangle but also its interior. Access to the two chambers from outside the box is provided by two vertical tunnels. The upper tunnel is made by punching out a square from the top of the box and another square directly below it from the middle horizontal rectangle, then inserting four vertical rectangles, the walls of the tunnel. This tunnel allows entry to the lower chamber from outside the box. the lower tunnel is formed in similar fashion, providing entry to the upper chamber. Finally, two vertical rectangles are inserted to form ‘support walls’ for the two tunnels. The resulting space X thus consists of three horizontal pieces homeomorphic to annuli plus all the vertical rectangles that form the walls of the two chambers.

ENCOURAGES IMAGINATIVE PLAY: 10 great accessories for imaginative play. Put Bing to bed or help him run a bath, lets use Brenda the Blender to bake a cake! If you want to take the easy way out instead, 12-year-old David Hitchman, son of University of Northern Iowa mathematician Theron J. Hitchman, made a fun video about building it in Minecraft, and Ken Baker wrote about it on the blog Sketches of Topology. There, he describes it in a different way:EXPLORE THE WORLD OF BING: 4 different room sets to explore and enjoy. Including a fold-out kitchen with opening and closing cupboards.

The Sisters remain in private ownership, and access is discouraged. Without hikers boots or swarms of trail bikes they grow a denser cloak of grass and shrub every year. Athletic cattle sometimes find their way up the lower levels of the bing in search of rare and tasty vegetation, but seem to do little damage Ican’t think about the house with two roomswithout hearing John 14:2: “In my father’s house there are many rooms.” This topological example is a bit more modest than the kingdom of God. After all, there are just two rooms.A more appropriate verse is this: In Bing’s house, there are two rooms. If it were not so, would Hatcher have told you how to construct it? We have therefore encouraged every provider to open their ‘online windows and doors’ to help you make an informed choice. The profile score is a measure of how much information has been provided. Contractible” is topological shorthand for “like a point” or, not to put too fine a point on it, “boring.” A space is contractible if it you can smush it down to a point without tearing the space or gluing any parts of it together.For example, a solid ball is contractible because even though it is three- rather than zero-dimensional like a point, it can be shrunk down all the way to a point without tearing or collapsing any of its interesting features. Hence, for some topological purposes, it’s close enough to being a point that we might as well assume it is.House with two rooms or Bing's house is a particular contractible, 2-dimensional simplicial complex that is not collapsible. The name was given by R. H. Bing. [1] Bing House Playset features popular CBeebies characters – Flop and Bing! Just like the house you see on the hit TV show. Beautifully made from tough, colourful plastic. Includes two posable figures and nine accessories. If your eyes glazed over a bit there, you’re not alone. The picture and description are hard to parse. Before we try to understand the space itself, we should figure out why we would bother with it at all. Hatcher uses it as an example of a space that is “contractible but not in any obvious way.”