does rationally suppose that the cause of this variation may be the inequality of the Earth variously disposed, and indifferently mixed with the Sea. The Needle driveth that way where the greater and most powerful part of the Earth is placed. For whereas on this side the Isles of Azores the Needle varies Eastward, it may be occasioned by that vast Tract, viz. Europe, Asia, and Africa, seated towards the East, and disposing the Needle that way. Sailing further it veers its lily to the West, and regards that quarter wherein the Land is nearer or greater; and in the same Latitude, as it approacheth the shore augmenteth its variation. Hence at Rome there is a less variation (viz. but five degrees) than at London, for on the west side of Rome are seated the great Continents of France, Spain, Germany; but unto England there is almost no Earth West, but the whole extent of Europe and Asia lies Eastward, and therefore at London the variation is 11 Degrees. Thus also, by reason of the great Continent of Brasilia, the Needle deflects towards the Land 12 Degrees; but at the Straits ⟨p. 106⟩of Magellan, where the Land is narrowed, and the Sea on the other side, it varies but 5 or 6. So because the Cape of De las Agullas hath Sea on both sides near it, and other Land remote, and as it were equidistant from it, the Needle conforms to the Meridian, In certain Creeks and Valleys it proveth irregular; the reason whereof may be some vigorous part of the Earth not far distant. Thus D. Brown, whose arguings seem, rational. Some have truly observed of Crocus Martis or Steel corroded with Vinegar, Sulphur, or otherwise, and after reverberated by Fire, that the Load-stone will not at all attract it: nor will it adhere, but lie therein like Sand. It is likewise certain, that the fire will cause the Load-stone to lose its virtue, inasmuch as its Bituminous Spirits are thereby evaporated. Porta (Lib.7. Cap. 7.) saith that he did to his great admiration see a Sulphurous flame brake out of the Load-stone which being dissipated, the Stone lost it's attractive virtue. Moreover, the Load-stone by being put into the fire may be caused quite to change its polarity. The truly Noble and Honourable Robert Boyle Esq, many of whose excellent Observations and experiments have been advantageous, not only to the English Nation but to the Learned World;
does rationally suppose that the cause of this variation may be the inequality of the Earth variously disposed, and indifferently mixed with the Sea. The Needle driveth that way where the greater and most powerful part of the Earth is placed. For whereas on this side the Isles of Azores the Needle varies Eastward, it may be occasioned by that vast Tract, viz. Europe, Asia, and Africa, seated towards the East, and disposing the Needle that way. Sailing further it veers its lilly to the West, and regards that quarter wherein the Land is nearer or greater; and in the same Latitude, as it approacheth the shore augmenteth its variation. Hence at Rome there is a less variation (viz. but five degrees) than at London, for on the west side of Rome are seated the great Continents of France, Spain, Germany; but unto England there is almost no Earth West, but the whole extent of Europe and Asia lies Eastward, and therefore at London the variation is 11 Degrees. Thus also, by reason of the great Continent of Brasilia, the Needle deflects towards the Land 12 Degrees; but at the Straits ⟨p. 106⟩of Magellan, where the Land is narrowed, and the Sea on the other side, it varies but 5 or 6. So because the Cape of De las Agullas hath Sea on both sides near it, and other Land remote, and as it were aequidistant from it, the Needle conforms to the Meridian, In certain Creeks and Vallies it proveth irregular; the reason whereof may be some vigorous part of the Earth not far distant. Thus D. Brown, whose arguings seem, rational. Some have truly observed of Crocus Martis or Steel corroded with Vineger, Sulphur, or otherwise, and after reverberated by Fire, that the Load-stone will not at all attract it: nor will it adhere, but ly therein like Sand. It is likewise certain, that the fire will cause the Load-stone to lose its vertue, inasmuch as its Bituminous Spirits are thereby evaporated. Porta (Lib.7. Cap. 7.) saith that he did to his great admiration see a Sulphurous flame brake out of the Load-stone which being dissipated, the Stone lost it's attractive vertue. Moreover, the Load-stone by being put into the fire may be caused quite to change its polarity. The truly Noble and Honourable Robert Boyle Esq, many of whose excellent Observations and experiments have been advantagious, not only to the English Nation but to the Learned World;
