is much larger than in front, in consequence of the numerous veins which empty into it as it proceeds. COVERINGS OF THE BRAIN. The brain has five separate coverings; 1st. The pia mater, or soft mother, so called from a belief that all the membranes of the body sprung from it. This is a thin, delicate, transparent membrane, that exactly fits the surface of the brain, sinking down into every furrow and convolution, and passing into every cavity; it acts as a kind of supporter to the numerous branches of blood vessels that traverse the external and internal surfaces of the brain in every direction. 2d. The tunica arachnoida, so called on account of its resemblance to a spider's web; this embraces the brain like network, but does not sink down into the depressions as the pia mater does; it is so delicate and fine that it was unobserved by ancient anatomists. 3d. The dura mater, or hard mother, a thick and strong membrane, passes over the tunica arachnoida and sinks down between the hemispheres in the median line; it serves to separate them from each other. This part or process of the dura mater is called the falx, on account of its resemblance to a scythe: another part passes between the cerebellum and cerebrum, and separates them from each other; this is called the tentorium. 4th. The skull or cranium is composed of six bones, The Frontal, of the forehead, The two Temporal, of the temples, The two Parietal, of the sides and top of the head, and The Occipital, at the back of the head. Besides these, are the Sphenoid, and Ethmoid bones at the base of the brain. The places where the edges of the bones are joined, are called sutures. The principal sutures are, The coronal, passing over the cranium and joining the frontal to the parietal bones. The squamous, or scaly sutures, that join the temporal to the parietal. The lambdoidal, joins the occipital to the parietal bones; this is so named because it resembles in form one of the Greek letters. The saggittal, that joins the two parietal together in the median line, so named from its resemblance to an arrow. There are many unimportant sutures in the base of the cranium that do not concern practical phrenology. The manner in which the sutures appear is called serated, or sawlike, on account of the manner in which the bones join each other. It is necessary to know the places of the sutures, as they frequently produce ridges that are mistaken for developements of brain; they may, however, be easily distinguished by their angular abrupt appearances. There are also several processes, or prominences of the skull, that are frequently mistaken by novices, for phrenological organs; one of these is the mastoid process, just behind the ear; this is sometimes mistaken for Combativeness, but is just below the main part of that organ, and is much more sharp and angular: another is the occipital spine, situated near Philoprogenitiveness, and is sometimes protruded more than an inch; Dr. Good very shrewdly suggested, that this bony process is intended to protect the brain in striking the back of the head on the ice. small prominence near Imperativeness, which in some cases modifies the appearance of that organ, and sometimes there is a slight depression just below this part, caused by the manner in which the bones united in infancy, making the organ appear small when it is full, but the depression is between Inhabitiveness and Imperativeness. case of falling and There is another If we break the skull and look at the broken edge, we shall see that it is not composed of solid bone all the way through, but there is a layer about as thick as a half dollar which constitutes the outer table, or that part of the skull next to the hair; there is another inner table next to the brain; and between the two tables is a spongy, coarse strata, called the diploe. In the average of white adults, the skull, including the two tables and the diploe, is near a quarter of an inch thick. The negroes have the thickest skulls I have ever seen: and I have observed that the thickness of the skull is in proportion to the coarseness of the constitution generally, and the developement of the oseous system in particular. The frontal sinus is a part of the skull, just over the organs of Individuality and Locality, where the inner and outer tables generally become more distant from each other, as age advances; allowing the diploe to occupy a larger space. This cavity renders it sometimes difficult to judge correctly concerning these organs, but its presence and size can be estimated by the peculiar swelling appearance which it assumes, being more sudden and abrupt than phrenological developements; besides, it does not exist in children, and even in adults it seldom becomes a serious obstacle to a skilful practitioner. 5th. The scalp is a very thin muscular integument, that covers the skull; this offers no obstacle to phrenological observation, except at the temple, in the region of Constructiveness and Acquisitiveness; here the mastoid muscle is situated, which sometimes renders this part prominent, like a developement of brain; but the thickness of the muscle is easily ascertained by pressing it firmly with the fingers, and causing the individual to move his jaw at the same time. CHAPTER V. CLASSIFICATION OF THE ORGANS. THE accidental and promiscuous manner in which Dr. Gall made his first discoveries, was extremely unfavorable to any systematic arrangement or philosophical explanation of the organs. Dr. Spurzheim has deservedly received much credit for improving the science in this respect, and correcting the very natural errors of his illustrious friend. The following is Spurzheim's last and most improved arrangement and nomenclature. ORDER 1-FEELINGS OR AFFECTIVE FACULTIES. Genus I.--Propensities. Genus 5. Combativeness. 6. Destructiveness. The following is the Classification adopted by Mr. George Combe, in his "System of Phrenology." There is no essential difference between him and Spurzheim except on the organ of Inhabitiveness. ORDER I.-FEELINGS. Genus I.-PROPENSITIES. 1. Amativeness. 2. Philoprogenitiveness. 3. Concentrativeness. 4. Adhesiveness. Alimentiveness. 7. Secretiveness. 8. Acquisitiveness. 9. Constructiveness. 27. 28. 29. 30. Genus II. SENTIMENTS COMMON TO MAN WITH THE LOWER ANIMALS. 10. Self-Esteem. 12. Cautiousness. 11. Love of Approbation. 34. Th of th follow pages FEEL facult PROP pensit |