Dr. Elliotson mentions a cast of the head of a male idiot, aged eighteen years, which he received from Dr. Formby, of Liverpool, and subsequently presented to the London Phrenological Society. It is only 16 inches in circumference, and 74 inches from ear to ear over the vertex. The cere brum weighed only 1 lb. 7 oz., and the cerebellum but 4 ounces.* Deficiency of size in the brain is not, however, the only cause of idiocy. A brain may be large and diseased, and mental imbecility may arise from the disease; but, as above shown, although disease be absent, if the size be very deficient, idiocy is invariable. Thirdly, Men who have been remarkable, not for mere cleverness, but for great force of character, such as Napoleon Bonaparte, Franklin, and Burns, have had heads of unusual magnitude. Fourthly, It is an ascertained fact, that nations in whom the brain is large, possess so great a mental superiority over those in whom that organ is small, that they conquer and oppress them at pleasure. The Hindoo brain, for example, is considerably smaller than the European, and it is well known that a few thousands of Europeans have subdued and keep in subjection millions of Hindoos. The brain of the aboriginal American also is smaller than the European, and the same result has been exem plified in that quarter of the world. Lastly, The influence of size is now admitted by the most eminent phy siologists. “The volume of the brain,” says Magendie, “is generally in direct proportion to the capacity of the mind. We ought not to suppose, however, that every man having a large head is necessarily a person of superior intelligence; for there are many causes of an augmentation of the volume of the head besides the size of the brain; but it is rarely found that a man distinguished by his mental faculties has not a large head. The only way of estimating the volume of the brain, in a living person, is, to measure the dimensions of the skull; every other means, even that proposed by Camper, is uncertain." The following passage, which occurs in the 94th number of the Edinburgh Review, also implies, not only that different parts of the nervous system, including the brain, have different functions, but that an increase of volume in the brain is marked by some addition to, or amplification of, the powers of the animal. "It is in the nervous system alone that we can trace a gradual progress in the provision for the subordination of one (animal) to another, and of all to man; and are enabled to associate every faculty which gives superiority with some addition to the nervous mass, even from the smallest indications of sensation and will, up to the highest degree of sensibility, judgment, and expression. The brain is observed progressively to be improved in its structure, and, with reference to the spinal marrow and nerves, augmented in volume more and more, until we reach the human brain, each addition being marked by some addition to, or amplification of, the powers of the animal-until in man we behold it possessing some parts of which animals are destitute, and wanting none which theirs possess." There is here, then, pretty strong evidence and authority for the assertion, that the brain does not form an exception to the general law of organized nature, that other conditions being equal, size of organ is measure of power of function.‡ Emotson's Blumenbach, p. 199. + Compendium of Physiology, Milligan's Translation, p. 104, edit. 1826 It is certified by hatters, that the lower classes of the community, who are distinguished for muscular vigour much more than mental capacity, require a smaller size of hat than those classes whose occupations are chiefly mental, and in whom vigour of mind surpasses that of body. But the phre nologist does not compare intellectual power with the size of brain in general; and, besides, the hat does not indicate the size of the whole head. The reader will find details on this point in the Phrenological Journal, iv. 539, and v. 213. The circumstances which modify the effects of size come next to be considered. These are constitution, health, exercise, excitement from without, and, in some cases, the mutual influence of the organs. The question naturally presents itself, Do we possess any index to constitutional qualities of brain? The temperaments indicate them to a certain extent. There are four temperaments, accompanied with different degrees of activity in the brain-the Lymphatic, the Sanguine, the Bilious, and the Nervous. The temperaments are supposed to depend upon the constitution of particular systems of the body: the brain and nerves being predominantly active from constitutional causes, seem to produce the nervous temperament; the lungs, heart, and blood vessels being constitutionally predominant, to give rise to the sanguine; the muscular and fibrous systems to the bilious; and the glands and assimilating organs to the lymphatic. The different temperaments are indicated by external signs, which are open to observation. The first, or lymphatic, is distinguishable by a round form of the body, softness of the muscular system, repletion of the cellular tissue, fair hair, and a pale skin. It is accompanied by languid vital actions, with weakness, and slowness in the circulation. The brain, as part of the system, is also slow, languid, and feeble in its action, and the mental manifestations are proportionally weak. The second, or sanguine, temperament is indicated by well-defined forms, moderate plumpness of person, tolerable firmness of flesh, light hair inclining to chestnut, blue eyes, and fair complexion, with ruddiness of countenance. It is marked by great activity of the blood vessels, fondness for exercise, and an animated countenance. The brain partakes of the general state, and is active. The bilious temperament is recognised by black hair, dark skin, moderate fulness and much firmness of flesh, with harshly expressed outline of the person. The functions partake of great energy of action, which extends to the brain; and the countenance, in consequence, shows strong, marked, and decided features. The nervous temperament is recognised by fine thin hair, thin skin, small thin muscles, quickness in muscular motion, paleness of countenance, and often delicate health. The whole nervous system, including the brain, is predominantly active, and the mental manifestations are proportionally vivacious. It is thus clearly admitted, that constitution or quality of brain greatly modifies the effects of size upon the mind: but let us attend to the consequences. As a general rule, all the parts of the same brain have the same constitution, and if size be a measure of power, then in each head the large organs will be more powerful that the small ones. This enables us to judge of the strong and the weak points in each head. But if we compare two separate brains, we must recollect that the size of the two may be equal, and that nevertheless the one, from possessing the finest texture and most vigorous constitution, may be exceedingly active, while the other, from being inferior in quality, may be naturally inert. The consequence may be, that the better constituted, though smaller, brain will manifest the mind with the greater vigour. That size is, nevertheless, the measure of power, may be proved by contrasting the manifestations of a small and of a large brain, possessing the same configuration, and equally well constituted; the power or energy will then be found superior in the latter. This illustrates what is meant by other natural conditions being equal. As the temperaments are distinguishable by the countenance and the general make of the body, and as the brain partakes of the general constitution, we possess a valuable, though not all-sufficient, index to its natural qualities. I repeat that these remarks apply only to the case of |