Until the discovery of the magnet they did not sail on the ocean far from land; but after it was discovered, then they made use of the magnetic needle balanced on the point so as to turn freely. By means of this needle they could tell in which direction they were sailing. With the magnetic needle they began to make long voyages far from land, and afterward they discovered many new countries.
There is always on board ship a magnetic needle, called the compass, and they have a measuring-line with knots, at the stern of the ship. And the cord is so constructed that it uncoils and tells how fast the vessel is sailing.
Thus it is that, when they sail a ship, they always know where they are at any given time, and whether they are far from land, and in what direction they are going.
CHAPTER II
humidity
Why does the spider sometimes make a closely spun web and sit in the very center of its nest, and why does it sometimes come out of its nest and spin a new web?
The spider makes its web according as the weather is at the time, and as it is going to be. By examining its web one can predict what the weather will be; if the spider hides itself away deep down in its nest and does not come out, it means rain. If it emerges from its nest and spins new threads, it means that it will be fine.
How can the spider tell in advance what the weather will be?
Its sensibilities are so delicate that as soon as the atmosphere begins to have greater humidity, even though this humidity is not perceptible to us, and to us the weather is still clear, the spider perceives that rain is coming. Just as a man feels the dampness when he is undressed, but does not feel it when he is dressed,
