so the rain is perceptible to the spider when for us it is only preparing to rain.
Why is it that in winter doors swell and refuse to shut, but in summer they dry up and shrink?
Because in autumn and winter the wood absorbs moisture like a sponge, and swells; but in summer the water evaporates and the wood shrinks.
Why does a soft wood like poplar swell more than oak, for example?
Because in the hard wood, in the oak, there are less empty spaces, and less room for the water to sink in; while in the soft wood, in the poplar, there are more empty spaces and more room for the water. In decaying wood there is still more room and therefore decayed wood swells more than any other kind and sinks sooner.
Beehives are made of the softest wood or of rotten wood; the best hives are made of rotten willow. Why? Because the air penetrates the rotten stump, and bees like the air in this kind of a hive.
Why do boards warp?
Because they dry unevenly. If you put a damp board into an oven, the water exudes from one side, and the board gets dry on that side and makes the other side yield to it. It is impossible to shrink the damp side because there is water in it and the whole board bends.
In order to keep floors from warping, they cut out pieces of dry wood and plunge them into boiling water. When the water has been wholly boiled away the pieces are glued together and will not warp, and this kind of inlaid floor is called a parket.
CHAPTER III
different degrees of coherence
Why is it that the bolsters under a wagon are made of oak while the naves of the wheels are turned out of birch?
It is necessary to have the bolsters and naves strong,
