The clock that stops for two seconds every minute

Watch the second hand of a station clock in Switzerland and you'll notice something odd: it sweeps the dial in about 58 and a half seconds, then sits still at twelve for a moment, as if catching its breath. Only when an electric impulse arrives from the master clock does the minute hand jump, and the second hand sets off again.

It was designed by the engineer Hans Hilfiker in 1944 for the federal railways. The problem was a serious one: thousands of clocks spread across hundreds of stations, and Swiss trains leave on the minute. The solution was not to let each clock keep its own count: every minute, one clock alone gives the order, and all the others obey at once. That pause of the second hand is the wait for the order.

The design —a clean dial, a red paddle like a station master's signal— became an icon. In 2012, Apple copied it for the iPad and ended up paying the Swiss railways a licence worth millions.

Swiss punctuality does not consist of every clock being exact. It consists of all of them waiting for the same signal.