The term has no real chronological value, for there has been no universal synchronous sequence of the three epochs in all quarters of the world.
Bleeding from an artery is of a bright red colour, and escapes from the end of the vessel nearest the heart in jets synchronous with the heart's beat.
The synchronous revolutions of the transmitting cylinders are effected by making one cylinder revolve slightly faster than the other; after each revolution the cylinder which is accelerated is arrested for a moment by means of a special relay until the difference of speed is accurately compensated for.
In the Hospitalier ondograph, 1 a synchronous electric motor driven in step with the periodic current in the circuit being tested drives a cylinder of insulating material having a metallic slip let into its edge.
Should the rotating arms fail to pass over these correcting segments at their synchronous positions, correcting currents pass to a relay which cuts off momentarily the current actuating the tuning-fork, thereby altering the rate of vibration of the latter until the arms once more run together uniformly.
It is clear that Swedenborg showed (150 years before any other scientist) that the motion of the brain was synchronous with the respiration and not with the action of the heart and the circulation of the blood, a discovery the full bearings of which are still far from being realized.
The most important innovation, however, was the transfer of the responsibility for filling up the schedule from the overseers to the householders, thereby rendering possible a synchronous record.
It must further be noticed that the rise of mercenaries was synchronous with a change in the nature of Italian despotism.