The book by the contemporary American philosopher and historian of science Peter Galison introduces the reader to how the procedure for coordinating clocks was developed at the turn of the 19th and 20th centuries, which later became one of the pillars of relativistic physics. The author focuses not only on the theoretical reasoning of famous physicists - primarily Einstein and Poincaré - but also on the extremely tangled tangle of diverse interests and practices belonging to navigators, astronomers, railroad workers, military men, businessmen and cartographers of those times, which allowed them to illustrate, discredit and anticipate the ideas of armchair scientists. The book is addressed to philosophers, historians of science, as well as a wide range of readers interested in the development of scientific thought.