Math
Galton Board
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Drop a ball through a triangle of pegs and it bounces left or right at random — but drop hundreds of balls, and they always pile up into the same smooth, bell-shaped curve at the bottom.
Book a visit and drop a few hundred balls — the pattern never fails.
Additional Information
This bell shape is called a normal distribution, and it shows up everywhere from test scores to human heights.
Each ball’s final position is the sum of many small random left-or-right bounces — individually unpredictable, but collectively very predictable.
The device is named after Francis Galton, who built the first one in the 1890s to demonstrate exactly this idea.