As with the sequence of Fibonacci you can draw a spiral in a golden rectangle, based on quarter circles. But now you start in reverse order: instead of creating larger squares each step you construct smaller squares in a fixed golden rectangle.[br][list][*]Draw a rectangle with ratios [math]\Phi[/math] and 1.[br][/*][*]Drawn within the rectangle a square with side the widt of the rectangle.[br]Now draw a quarter circle into the square.[/*][*]The remaining part of the rectangle on its turn is again a golden rectangle. So again you can create smaller squares and golden rectangles. The result is a spiral.[/*][/list]Note:[br][list][*]as the Fibonacci spiral this isn't a real spiral around a fixed point with a constant in(de)creasing radius. Every quater circle a new center is chosen to draw a circular arc with fixed radius.[/*][*]This spiral looks like the Fibonacci spirall, but it's not the same.[br]The reason is the relation between the sequence of Fibonacci and the number [math]\Phi[/math].[br]In the golden rectangle the ratio between consecutive sides of the squares always equals [math]\Phi[/math]. In Fibonacci squares the ratio approaches [math]\Phi[/math] but is always slightly different.[br][/*][/list]