He marveled at Westlake's lack of concern, but as a first time visitor to the heart of nature's fury it was still a white-knuckle trip as lightning flashes and near-simultaneous thunderclaps erupted in every direction.
Observations are made at a given height over level open ground near the observatory, and a comparison with the simultaneous results from the self-recording electrograph enables the records from the latter to be expressed as potential gradients in the open.
Elster and Geitel found the sign of the charge often fluctuate repeatedly during a single rain storm, but it seemed more often than not opposite to that of the simultaneous potential gradient.
A conflict between Corcyra and Corinth, the second and third naval powers of Greece, led to the simultaneous appearance in Athens of an embassy from either combatant (433) Pericles had, as it seems, resumed of late a plan of Western expansion by forming alliances with Rhegium and Leontini, and the favourable position of Corcyra on the traderoute to Sicily and Italy, as well as its powerful fleet, no doubt helped to induce him to secure an alliance with that island, and so to commit an unfriendly act towards a leading representative of the Peloponnesian League.
Duplex telegraphy consists in the simultaneous transmission of two messages, one in each direction, over the same wire.