La ville sans toits…………..

Best Experienced With: Arcade Fire; Wake Up

(please right click on the link below to open up the suggested background music for this afternoon’s treatise in a new browser window. What a fantastic, moving little tune. Please turn the volume to 11 for the best results.)

http://www.youtube.com/watch?v=DEKC5pyOKFU

Bernoulli’s Principle allows us to fly. Danny B was a Swiss scientist who discovered that as the velocity of a fluid increases, its pressure decreases. Since air is a fluid, Danny B’s principle applies to air. An airfoil’s camber increases the velocity of air moving over the top of the wing. The resulting pressure differential causes lift…………..and up we go.

Shifting of tectonic plates causes earthquakes. Our planet has three main layers: the inner core, the middle mantel, and the outermost crust. The latter two form the strong lithosphere with the lithosphere further broken into plates called tectonic plates fitted together like a puzzle, or like this recently cobbled together “healthcare for everyone (!)” plan here in the United States.

When the mantel moves, the plates move towards or away from each other. Movement can either be compressional, transformational, or extensional. When plates collide, the edges rip and create energy in the form of seismic waves. The combination of Rayleigh waves and Love waves create both the rolling waves and the side to side twisting seen in earthquakes.

Rebar is steel bar used to reinforce concrete structures. It holds concrete neatly in place, when used properly. Steel is expensive and scarce in developing nations.

Deforestation is the unplanned and non-scientific method of logging or burning forest trees. Deforestation is typically caused by unsound agricultural practices, overpopulation, over logging, and increased competition for scarce land. Deforestation is further complicated when an entire population cooks only over charcoal. Less than 2% of Haiti’s land is forested today. Deforestation causes continual and severe soil erosion, further lowering the productivity of available land. When left unchecked, deforestation creates what the scientists in The Land of Cleve used to call a “toilet bowl effect”.

When a city either chooses not to use rebar in its buildings or is unable to afford rebar and the tectonic plates shift, the city becomes la ville sans toits.