_A._ If you put into a basin of water a long rag of cloth, first drenched in water, and let the longer part of it hang out, it is known by experience, that the water will drop out as long as there is any part of the other end under water. _B._ The cause of it is, that water, as I told you, hath a degree of tenacity. And therefore being continued in the rag till it be lower without than within, the weight will make it continue dropping, though not only because it is heavy (for if the rag lay higher without than within, and were made heavier by the breadth, it would not descend), but it is because all heavy bodies naturally descend with proportion of swiftness duplicate to that of the time; whereof I shall say more when we talk of gravity. _A._ You see how despicable experiments I trouble you with. But I hope you will pardon me. _B._ As for mean and common experiments, I think them a great deal better witnesses of nature, than those that are forced by fire, and known but to very few. ========== CHAPTER VI. OF THE CAUSES AND EFFECTS OF HEAT AND COLD. _A._ It is a fine day, and pleasant walking through the fields, but that the sun is a little too hot. _B._ How know you that the sun is hot? _A._ I feel it. _B._ That is to say, you know that yourself, but not that the sun is hot. But when you find yourself hot, what body do you feel? _A._ None. _B._ How then can you infer your heat from the sense of feeling? Your walking may have made you hot: is motion therefore hot? No. You are to consider the concomitants of your heat; as, that you are more faint, or more ruddy, or that you sweat, or feel some endeavour of moisture or spirits tending outward; and when you have found the causes of those accidents, you have found the causes of heat, which in a living creature, and especially in a man, is many times the motion of the parts within him, such as happen in sickness, anger, and other passions of the mind; which are not in the sun nor in fire. _A._ That which I desire now to know, is what motions and of what bodies without me are the efficient causes of my heat.