Buffon's Needle Buffon's Needle was first posed by Comte de Buffon in 1777. He stated that if there existed a plane, ruled with parallel lines D distance from each other, and one was to drop a needle of length D on to that plane, the probability that the needle would cross one of the lines was exactly 2/π. This phenomenon is a result of the angle of the dropped needle. Since the probability is based on the vertical length of the needle ((L sin A) where L is the length of the needle and A is the angle of the needle). The following example applet illustrates that the probability closes on pi but takes a very long time as compared to other methods. In order to begin the simulation, click the "Start" button. Pressing the "Start" button again restarts the simulation. The graph on the right shows the estimated value of pi based on the simulation versus the log of the number of needles thrown. The end of the graph represents 100000 needle throws. This browser is not Java-Enabled. For more interesting historical facts, visit the History section, or for more ways to find π, check out the What is π seciton.