17. All sciences are joined to and succeed one another in rational order. One is born of the other, according as they find support in anterior knowledge and ideas. Astronomy, one of the first which might have been cultivated, has remained in the infancy of its errors till the moment when physics came to reveal the law of the forces of the natural agents. Chemistry, being unable to do anything without physics, must come next in succession, in order that they should walk together, and learn upon one another. Anatomy, physiology, zoology, botany, and mineralogy have been recognized as veritable sciences only by the aid of the lights carried by physics and chemistry. Geology, born of yesterday, without astronomy, physics, chemistry, and others, would have failed to possess true elements of vitality. It could not be born until they had been recognized.