3. Furthermore, the piercing cold of the gross thick air so near the Pole will so stiffen the sails and ship tackling, that no mariner can either hoist or strike them--as our experience, far nearer the south than this passage is presupposed to be, hath taught us--without the use whereof no voyage can be performed. 4. Also, the air is so darkened with continual mists and fogs so near the Pole, that no man can well see either to guide his ship or to direct his course. 5. Also the compass at such elevation doth very suddenly vary, which things must of force have been their destruction, although they had been men of much more skill than the Indians are. 6. Moreover, all bays, gulfs, and rivers do receive their increase upon the flood, sensibly to be discerned on the one side of the shore or the other, as many ways as they be open to any main sea, as the Mediterranean, the Red Sea, the Persian Gulf, Sinus Bodicus, the Thames, and all other known havens or rivers in any part of the world, and each of them opening but on one part to the main sea, do likewise receive their increase upon the flood the same way, and none other, which the Frozen Sea doth, only by the west, as Master Jenkinson affirmed unto me, and therefore it followeth that this north-east sea, receiving increase only from the west, cannot possibly open to the main ocean by the east. 7. Moreover, the farther you pass into any sea towards the end of it, of that part which is shut up from the main sea, as in all those above-mentioned, the less and less the tides rise and fall. The like whereof also happeneth in the Frozen Sea, which proveth but small continuance of that sea toward the east. 8. Also, the farther ye go towards the east in the Frozen Sea the less soft the water is, which could not happen if it were open to the salt sea towards the east, as it is to the west only, seeing everything naturally engendereth his like, and then must it be like salt throughout, as all the seas are in such like climate and elevation. And therefore it seemeth that this north-east sea is maintained by the river Ob, and such like freshets as the Pontic Sea and Mediterranean Sea, in the uppermost parts thereof by the river Nile, the Danube, Dnieper, Tanais, etc. 9. Furthermore, if there were any such sea at that elevation, of like it should be always frozen throughout--there being no tides to hinder it--because the extreme coldness of the air in the uppermost part, and the extreme coldness of the earth in the bottom, the sea there being but of small depth, whereby the one accidental coldness doth meet with the other; and the sun, not having his reflection so near the Pole, but at very blunt angles, it can never be dissolved after it is frozen, notwithstanding the great length of their day: for that the sun hath no heat at all in his light or beams, but proceeding only by an accidental reflection which there wanteth in effect.