The Dutch Tiphys

...investigation, no help or protection was available anywhere. Finally, the Magnet original: Magnes; referring to the lodestone or magnetic compass was discovered and dug out from the very bowels of the earth; a stone unpolished indeed, without luster, dark, rough, and scabby, with a rusty color; but yet to be compared against any gemstone. This is that magnet which, having taken pity on us like a most dutiful guide ξεναγωγος (xenagōgos): a Greek term for a guide or leader of strangers, leads wretched mortals—even those reckless with their own lives—safe and sound across the whole world. Even in the darkness, it shines a torch upon those errors; and by night or by day, like some attendant original: nomenclator; historically a servant who announced names or provided directions, it reports the regions of all courses and performs the duty of a faithful monitor.

And from that point, the thought was struck into sagacious men to scrutinize more accurately the properties of these courses. From which it was immediately noted that a very fine method for investigating longitude and latitude could be derived from this source; and that from the region of the course and its estimated quantity, these coordinates come daily to the calculation table original: abacum; referring to a counting board or maritime chart used for calculation.

Therefore, for an entire century now, both the learned and the unlearned have labored in competition to scrutinize the laws of that line which is described by ships under the guidance of the magnetic needle original: magneticæ acus, and to explain them more accurately. Since there exists no other way of finding longitude in the middle of the sea except that one which is drawn out by the evidence of the magnetic needle. And indeed, all the maritime shores have long been hammering at this anvil original: incudem; a metaphor for working tirelessly on a difficult problem; and not only privately, but also publicly. Your [Honors] have also felt this matter,