This is obtained by causing one of them to send a series of signals from one particular key, while the operator at the other station adjusts his speed until he receives the same signal after shortcircuiting his electromagnet for ten revolutions.
Against the attendant abuses the Augustinian monk Martin Luther posted (31st October 1517) on the church door at Wittenberg his famous ninety-five theses, which were the signal for widespread revolt against the church.
Even in the early part of the 19th century sentinels stood on duty night and day, and at a signal of alarm the whole population, including the Turkish aga himself, used to hide in the woods.
He thereby gave the signal for the age-long conflict between Nominalism and Realism, which exercised the keenest intellects among the Schoolmen, while the crowning work of his life, the Consolatio Philosophiae (524), was repeatedly expounded and imitated, and reproduced in renderings that were among the earliest literary products of the vernacular languages of modern Europe.
Moreover the clearing-out drop of the cord circuit was replaced by an arrangement which included the provision of one signal to be controlled through the agency of a relay by the calling subscriber, and another to be controlled by the person wanted.
His nomination by Lord John Russell to the vacant see of Hereford in December 1847 was again the signal for a violent and organized opposition; and his consecration in March 1848 took place in spite of a remonstrance by many of the bishops and the resistance of Dr John Merewether, the dean of Hereford, who went so far as to vote against the election when the conge d'elire reached the chapter.
In the not too distant future, tiny robots will detect pests on produce and emit a signal to shoo them away.
Pelagius himself desired to avoid controversy, and with mental reservations denied these statements of his friend; but he did not escape suspicion, and his condemnation in 418 was the signal for a literary polemic, which lasted ten years, and in which Julian of Eklanum was the most brilliant but reckless combatant on the side of Pelagius.
They were always ready to come to blows, and gave still more signal proofs of their enmity during the Sicilian War in behalf of the emperor Henry VI.
He has not bequeathed an imposing system, hardly even a striking discovery in metaphysics, but he is a signal example in the Anglo-Saxon world of the love of attainable truth for the sake of truth and goodness.