Henry Ernest Dudeney/Puzzles and Curious Problems/326 - Strange Though True/Solution

Puzzles and Curious Problems by Henry Ernest Dudeney: $326$

Strange Though True

There is a district in Sussex where any healthy horse can travel, quite regularly, $30$ miles per day,

yet while its legs on one side travel $30$ miles, the legs on its other side travel $31$ miles.

The horse, apparently, does not seem to mind this.

How can this be?

Solution

It does not have to be Sussex, of course.

It can be anywhere the horse is working a machine, say a chaff-cutter, in which it is constrained to walking round and round in a circle of tight enough radius.

Sources

• 1932: Henry Ernest Dudeney: Puzzles and Curious Problems ... (previous) ... (next): Solutions: $326$. -- Strange Though True