142 THE INTELLECTUAL RISE IN ELECTRICITY. 



the ship, and of all the lives she carries, directly depends. 

 Even a slight error in its indication may lead the vessel 

 far out of her course or into fatal perils. That this must 

 have been perceived by the first sailors who used it, is 

 altogether probable; indeed, we can easily imagine their 

 terror and apprehension, when they found themselves out 

 of sight of land and the familiar Pole star obscured by 

 clouds, relying solely upon the pointing of the little 

 needle, quivering in its bowl of water, to show them 

 the way. Wreckers and pirates in mediaeval times were 

 common, and when the sea-villains learned how implicit 

 the reliance was upon the compass, and how by slightly 

 falsifying it they might bring a richly-laden craft upon 

 the rocks and so into their toils, opportunities for this 

 mode of plying their trade quickly revealed themselves. 

 Obviously, it was much easier to conspire with the crew, 

 or to send one of their own stripe on board in the guise of 

 an honest seaman, to tamper with the needle, and so bring 

 the ship to wreck in some previously-determined region, 

 than to seek to capture her in the open fight for which all 

 vessels then sailed prepared. Therefore, as by common 

 consent, all sea-faring men regarded falsification of the 

 compass as an offense, worthy of the severest punishment. 

 Tampering with the compass, moreover, in those days 

 was supposed to be very easy, and no doubt many an un- 

 fortunate sailor lost his life under the charge of so doing 

 when in fact he was innocent. The lodestone (with 

 which the needle was rubbed) was then supposed to be 

 affected by influences which are really destitute of the 

 slightest effect upon it. Among the superstitions relating 

 to it none, for example, was more common than the be- 

 lief that its attractive power could be destroyed or weak- 

 ened by the touch, or even the odor, of onions or of garlic. 

 As Neckam notes, the proximity of the diamond was 

 supposed to have a like effect; but diamonds were not 

 ordinarily in the possession of mariners, while the odorous 

 vegetables were, and so much was their effect feared that 



