agility, cunning, vigilance, fortitude, and moral resolution qualities whose exertion makes heavy drafts upon the cerebral apparatus. Moreover, the savage man, as represented in the North American Indian, is strikingly distinguished from the slave, or peasant, by an active imagination, a free fancy, sublime sentiments, and a high style of eloquence-indicating an active and vigorously worked brain. Further, even his agility is a modification of muscular action, requiring combination and co-ordination so rapid and precise, as to demand that the nervous system be called into the tensest action, when he would effect them. Duly estimating all this constant strain upon the sensitive, mental, and co-ordinating nervous system, we have the deficiency of sexual feeling well accounted for, and quite in harmony with the general ideas above propounded. So, again, in the Greek mythology, Diana, goddess of chastity, being significantly represented as patroness of the chase. Turning thence to the public games of Greece, we find the sexual intercourse regarded as being quite as unfavorable to severe exercise as the latter could be to it, and therefore prohibited to the athlete while in course of training. The attraction and counter-attraction, or antagonism, of the nervous and sexual functions, is thus verified by the precise phenomena which might, at first, appear to constitute exceptions to the law.

Another fact in the natural history of our subject affords additional confirmation of the views that have been thus suggested. In the order of nature, puberty, or the capacity of reproduction, appears in the individual about the time that the intellectual and moral powers attain a force sufficient to control the instincts— the brain thereafter losing none of its balancing power, but rather gaining upon the propensities as men advance in age. This correspondence of development and continence marks a closely fitting relation of combination between them the efficiency of the constitutional disposition of the respective forces being thus accommodated by help of an auxiliary moral force. Only in man is the sexual impulse equally active, equally responsive to restraint, at all times, and at every season. Unlike the lower animals, he has no annual season of love, irrepressible and irresistible. The propensity beginning with the beginning vigor of his intellect, is thus placed under the control of reason and sentiment, functions of the

cerebral system, whose efficiency is in the direct proportion of the healthy development of the system, of which they are a part.

It is not, however, by moral resistance and prudential restraints, alone, that the admirable ends of providential order are to be secured the law being woven into the very texture of the organs concerned in the process of reproduction. A physical law here adjusts the balances, maintains the harmonies, and achieves the beneficent results desired.

Some evidence, needing to be cautiously weighed, yet too important to be entirely thrown aside, is found in the varied brains. of the several families of mankind. Dr. Morton, who collected together the greatest number and variety of human crania to be found in the world, and whose competency and care in making their measurements, as well as his inferences therefrom, were such as were well calculated to secure for his report thereon the fullest confidence, published a catalogue of 623 skulls-representing all the known human families, both ancient and modern, and giving of each so many specimens as to afford a tolerably fair average of their respective capacities. Eighteen German, five English, and seven Anglo-American skulls, ranging from 114 cubic inches down to 82, gave the mean size of the brain at 92 inches. Fiftyfive ancient Egyptian skulls, ranging from 96 to 68, gave a mean of 80 inches. One hundred and sixty-one skulls of barbarous American Indians-the largest reaching 104 inches, and being second in rank in the whole catalogue-gave an average of 84. Eighty-five negro heads the largest 99, and the smallest 63gave an average of 78. In this collection the largest German brain measured 10 inches more than the largest Iroquois, and 15 more than the largest negro.*

Some confirmation is certainly afforded by these measurements, to the theory which antagonizes the brain and the sexual system in their functions-it being unquestionable that the size of an organ bears a direct relation to its vital force, and that its volume is increased by exercise. All other things being equal, size affords reliable evidence of power. The argument, however, does not depend upon the facts of craniology-the fact we really need being that of the greatly superior activity of the highly developed man, when compared with the unthinking and uncultivated * MORTON: Catalogue of Skulls, Philadelphia, 1849.

drudges of civilization. To those capable of ordinary observation and reflection, this needs no scientific proof, and if mental and physical culture be really the condition indicated by physiology, as the corrective of relatively excessive procreation, the law upon which we rely may be regarded as established.

The law of balance between the nervous and sexual functions is strongly corroborated by the facts of comparative physiology, some of which have been before referred to. The queen ant of the African termites lays 80,000 eggs, and the hair-worm as many as 8,000,000, in a single day. Carpenter says, "that above 1,000,000 eggs are produced at once by a single codfish, whereas, in the strong and sagacious shark, but few are found." The higher ranks of reptiles are still less fertile; and among the mammalia, those which quickly reach maturity produce large and numerous litters-those, on the contrary, which are longer in attaining the reproductive age, and are better provided with brain, producing annually but a single litter. Higher in rank are those producing singly the series terminating with the elephant, who, in virtue of his nobler nervous system, and its accompanying reasoning powers, presents himself as least prolific of them all.

The general law of life, throughout all the classes, orders, genera, species, and individuals, may thus be stated:

The nervous system varies directly as the power to maintain life:

The degree of fertility varies inversely as the development of the nervous system — animals with larger brains being always the least, and those with smaller ones, the most prolific :

The power to maintain life, and that of procreation, antagonize each other that antagonism tending perpetually towards the establishment of an equilibrium.

Chemical analysis, though less accurately and conclusively ascertained than might be wished, presents itself in aid of the views thus suggested—exhibiting to us the fact, that the sperm cells of the fecundating fluid, and the neurine, or essential portion of the cerebral substance, possess in common one element—unoxydized phosphorus-by which they are specially characterized and distinguished. Of this peculiar substance, no less than 6 per cent. enters into the solid contents of the brain of adults. In advanced age, it falls to 33; and in idiots, it is less than 3.

No

Here, however, as in the argument drawn from the relative size of the brain of the various races of the species, the evidence afforded by experience, and by physiological laws, is more conclusive than that obtained by examination of the structure. thing connected with this question is better known-nothing more fully recognised - than the general antagonism of the nervous and generative systems. Intense mental application, involving great waste of the nervous tissue, and corresponding consumption of the nervous element for its repair, is accompanied by a proportionately diminished production of sperm-cells the excessive production of these latter being, in like manner, followed by defective cerebral energy. In the degree usually regarded as disease, the process is marked first by headache, followed by stupidity, leading to imbecility, and terminating in insanity.

How this antagonism of action affects the female system, is less clearly open to scientific examination, although it appears highly probable, that the provision of nervous matter, as well as of nutriment, to the embryo, limits the supply of nervous matter to the maternal system. So far as mere substance is concerned, this must have some force, wheresoever and whensoever it applies. It is, however, more probable, that the uterine function, beginning with puberty, and continuing until the commencement of old age, is the more efficient counteractive of cerebral force in the sex - the state of health, and eminently that of disease, furnishing strong evidence to this effect.

Further, there is abundant reason for believing, that certain kinds of nervous action are more efficient than others, in counteracting the activity and force of the instincts, and the functions which they serve, although the physiology of the brain is not, as yet, sufficiently advanced to render us adequate service hereneither its anatomy, nor its chemistry, yet answering to all the questions which social science puts to them. It being, however, satisfactorily established, that the various parts of the cerebral mass have different offices assigned to them, it is probable, even on this ground, that they have varied relations, both of assistance and of counter-balance, to the action of the viscera. The employment of the mind in passional, imaginative, scientific, moral, or devotional applications, has effects upon the propensities, that, as we know, are widely different. Some of them, cer

tainly, minister to their growth, while others as decidedly counteract it. Experience here affords valuable instruction, not only for the conduct of life, but as furnishing important data for inquiry all its teachings having an obvious bearing upon the question now before us.

The application of the several points that, as we think, have been secured, would seem to be as follows:

The human race being in a state of transition, we have all the reasons thus far offered, for believing that the existing ratio between its ability to multiply, and its power to maintain life, is not a constant quantity-the causal law being one, but its effects being modified by almost incessant changes in the conditions upon which it operates. In certain states of society, we find reproduction going ahead of the supply of food-admitting that we take, for the terms of the problem, the apparent for the true law, in accordance with the views of Mr. Malthus. In other conditions of society, as in the case of the North American Indians, no such disproportion existed, previously to the European immigration. Only in certain states of society, claiming to be held as civilized, does history give any color to the assumption opposed to our theory of balance and harmony- the preponderance of population in a country like Ireland being, however, well accounted for, as the necessary provision of a relatively redundant life, to meet the waste occasioned by societary and individual disorder. This, however, is not the normal condition of human existencenot the orderly result of the supreme law which rules in the constitution of things. It is the casual conformity of constitutional forces to accidental exigencies.

Looking, now, to the constant advancement, and ultimate perfection, of civilization, what is it we may expect from the operation of the self-adjusting law, whose existence we thus have sought to establish? All the facts of the past tend to prove, that mere muscular labor, unenlightened toil, accompanied by a general feeling of security, and unattended, therefore, by those cares which stimulate to action the nervous system of the savage, favors fertility, or permits it in the highest degree known to experiencethat fertility being attended by great mortality. Civilization tending, however, towards the substitution of the natural forces for human labor, the life of the masses will not, in the future, be sub