By another, but more inaccurate method, the attraction of the earth has been compared with that of a mountain--a very indefinite method indeed. A better method was that of Astronomer Airy and Mr. Dunkin, who went down into the Harton coal pit 1,260 feet to see how much difference that depth would make in the movements of a pendulum. It gained 2-1/4 seconds in 24 hours, and the weight of the earth was inferred to be over 6-1/2 times as great as that of water; but it is manifest that such a method could yield nothing much more accurate than the mountain experiment which indicated a weight 4-3/4 times that of water. The ball experiment, which is the most reliable, indicated 5-1/2 times the weight of water, thus coinciding with Newton's astronomical opinion, which is probably true. HEAD AND HEART.--The popular use of the terms head and heart to represent thought and emotion, which is contrary to physiology, is analogous to Dr. Hartmann's statement of the oriental doctrine that thought alone belongs to the brain, but life and will to the heart. This ancient _speculation_ (not intuition) is easily refuted. If it were true, the will power and powers of life would be proportional to the development of the heart, regardless of the brain, but the reverse is the fact. Great development of heart does not increase either will power, or life, but is injurious to both. The enlarged (hypertrophied) heart is injurious to vital power and will power, and in proportion to its increase, it tends to shorten life by apoplexy or some other form of cerebral disorder. It produces no increase of either life, will, or love. In fact, the stomach is more nearly associated with love than the heart, for men are much more amiable after enjoying a feast, but the heart, which is a part of the muscular system, is at its maximum of action in combat and war. THE RECTIFICATION OF CEREBRAL SCIENCE, commenced in this number, will be continued in the November number, bringing the science up to its present condition, and showing how, after the rectification is completed, the science attains a grand simplicity, and, instead of being puzzled by cerebral organology, a very brief instruction will enable us to master the subject. In 1836 I instructed Prof. Cubi at New Orleans in the old organology, giving him six lessons in exchange for his instructions in Spanish. Three lessons would give an equal familiarity with the new system, though it is four times as extensive. CHAPTER IX.--RECTIFICATION OF CEREBRAL SCIENCE, CORRECTING THE ORGANOLOGY OF GALL AND SPURZHEIM.