Why Old Railroads Had Gaps
Animated Short, 0:52. Published 2026-11-09.
Why do train tracks have gaps in between?
The story is made up; the science is real: steel grows when it heats up. A 39 ft rail can grow about 6 mm on a hot day, so old jointed track left small gaps. Track with no room can buckle in the heat (a "sun kink").
Transcript
He cut a gap between every rail. Every thirty-nine feet. Two railroads are racing across the desert, and whoever finishes first gets every train in the state. His boss sees the gaps, and his face goes red. You're building a broken railroad! But he won't close a single one. The other crew lays their rails tight, end to end.
One perfect line. And they finish first. Their trains glide in silence. His go clack, clack, clack, and the papers call it the Rattle Line. Then summer hits. His gaps start shrinking. In June, a finger fits. By August, barely a coin. Because steel grows when it gets hot. And the perfect railroad has nowhere to grow.
On the hottest day of the year, his gaps finally close. Rail touching rail. And the perfect railroad bends sideways like a snake, just as the evening train comes around the corner.
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Unfold Animated. Funny cartoons that make you smarter. No AI images, no AI video. Real facts, checked.