formed to. This fate frequently overtakes uneducated women, whose early days have been occupied with business or the cares of a family, but whose occupations have ceased before old age has diminished corporeal vigour. It overtakes also uneducated men who retire from active business in the prime of life. In some instances, these evils accumulate to such a degree that the brain at length gives way, and insanity is the consequence.

It is worthy of remark, that the more elevated the objects of our study, the higher in the scale are the mental faculties which are exercised; and that the higher the faculties, the more pure and intense is the pleasure. Hence, a vivacious and regularly supported excitement of the moral sentiments and intellect is highly favourable to health and corporeal vigour.

No reasonable person, after having his intellect imbued with a perception of, and belief in, the natural laws now explained, can desire continued idleness as a source of pleasure; nor can he regard muscular exertion and mental activity, when not carried to excess, as anything else than enjoyments, vouchsafed to him by the benevolence of the Creator. The notion that moderate labour and mental exertion are evils, can originate only from ignorance, or from viewing the effects of over-exhaustion as the natural result of labour, and not as the consequence of its excess, which the natural laws forbid.

If, then, we sedulously inquire, in each particular instance, into the cause of the sickness, pain, and premature death, or the derangement of the corporeal frame in youth and middle life, which we see so common around us, and endeavour to discover whether it originated in obedience to the physical and organic laws, or sprang from infringement of them, we shall be able to form some estimate how far bodily suffering is justly attributable to imperfections of nature, and how far to our own ignorance and neglect of Divine institutions.

The foregoing principles being of much practical importance, they may with propriety be elucidated by a few examples. Two or three centuries ago, various cities in Europe were depopulated by the plague, and, in particular, London was visited by an awful mortality from this cause, in the reign of Charles II. Some people of that age attributed the scourge to an inscrutable decree of Providence, and others to the magnitude of the nation's moral iniquities. According to the views now presented, it must have arisen from

infringement of the organic laws, and have been intended to enforce stricter obedience to them in future. There was nothing inscrutable in its causes or objects. The streets of London were then excessively narrow, the habits of the people dirty, their food poor, and no adequate provision was made for introducing a plentiful supply of water, or removing the filth unavoidably produced by a dense population. The great fire in that city which happened soon after the pestilence, afforded an opportunity for remedying in some degree the narrowness of the streets, while habits of increasing cleanliness abated the filth. These changes brought the condition of the people more into accordance with the laws of health, and the plague has not since returned. It thus appears to have had no direct reference to the moral condition of the people; I say direct reference, because it would be easy to show that the physical and organic laws. are connected indirectly, and act in harmony, with the moral law; and that infringement of the latter often leads to disobedience of other laws, and brings a double punishment on the offender.

Till lately, thousands of children died yearly of the smallpox; but in our day, vaccine inoculation saves ninety-nine out of every hundred, who without its protection would have died.

A gentleman who died in the early part of this century at an advanced age, told me that in his youth the country six miles west from Edinburgh was so unhealthy, that every spring the farmers and their servants were seized with fever and ague, and underwent bleeding and a course of medicine to prevent attacks or remove their effects. At that time these visitations were believed to be sent by Providence, and to be inherent in the constitution of things. But, said my informant, after an improved system of agriculture and drainage was established, and the numerous pools of stagnant water formerly left between the ridges of the fields were removed, after dunghills were carried to a distance from the doors, and the houses were made more spacious and commodious,-every symptom of ague and marsh-fever disappeared from the district, and it became highly salubrious. In other words, as soon as the gross infringement of the organic laws was abated by a more active exertion of the intellectual and muscular powers of Man, the consequences of that infringement ceased. Another friend informed me.

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that, about the end of last century, he commenced farming in a high and uncultivated district of East Lothian; that at first the crops suffered severely in the spring from cold fogs, but that the region had since been reclaimed and drained, and the climate had greatly improved;-in particular, the destructive mists had disappeared. The same results have followed in Canada and the United States of America, from similar operations.

In like manner, many calamities occurred in coal-pits, in consequence of introducing lighted candles and lamps into places filled with hydrogen-gas, which had emanated from seams of coal, and which, by exploding, scorched and suffocated the men and animals within its reach; until Sir Humphry Davy discovered that the Creator had established such a relation between flame, wire-gauze, and hydrogengas, that, by surrounding and covering the flame with gauze, its power of setting fire to hydrogen was suspended. In consequence of this discovery, colliers are now able to carry, with safety, lighted lamps into places highly impregnated with inflammable air. I have been informed that the accidents from explosion, which still occur in coal-mines, arise from neglecting to keep the lamps in a proper state.

It is unnecessary to multiply examples in support of the proposition that the human organism in itself admits of a healthy existence from infancy to old age, provided its germ has been healthy, and its subsequent condition has been one in harmony with the physical and organic laws. But it has been objected, that, although the intellect may perhaps be adequate to discover these laws, and to record. them in books, it is totally incapable of remembering them, and of formally applying them in every act of life. If, it is said, we could not move a step without calculating the effects of gravitation, and adjusting the body to its influence, -if we could never eat a meal without carefully considering how much we might swallow in accordance with the organic laws,-life would be oppressed by the pedantry of knowledge, and rendered miserable by the observance of trivial details. To this objection I reply, that our faculties are adapted by the Creator to the external world, and act spontaneously. when their objects are properly placed before them. In walking during the day on a footpath in the country, we adjust our steps to the inequalities of the surface without being overburdened by mental calculation. With so little

trouble, indeed, do we perform this adjustment, that we are not aware of having made any particular mental or muscular effort. But on returning by the same path at night, when we cannot see, we stumble, and discover how important a duty our faculties had been performing during the day. Now, the simple medium of light is sufficient to bring clearly before our eyes the inequalities of the ground; but to make the mind equally familiar with the countless objects which abound in external nature, and their relations, an intellectual light is necessary, which can be struck out only by exercising and applying the knowing and reflecting faculties. When that light is obtained, and the qualities and relationships in question are clearly perceived, our faculties, so long as the light lasts, will act spontaneously in adapting our conduct to the nature of the objects, just as they do in accommodating our movements to the unequal surface of the earth. After the poisonous qualities of hemlock are known, it is no more necessary for us to go through a course of reasoning on physical, botanical, and chemical objects, in order to be able to abstain from eating it, than it is to go through a course of mathematical investigations before lifting one foot higher than the other in ascending a stair. At present, physical and political science, morals, and religion, are not taught as parts of one connected system; nor are the relations between them and the constitution of Man pointed out to the people. Consequently, theoretical and practical knowledge are often widely separated. This ought not to be the case; for many advantages would flow from systematic scientific education. Some of these may now be mentioned.

In the first place, the physical and organic laws, when thoroughly known, appear to the mind as institutions of the Creator, wise and salutary in themselves, unbending in their operation, and universal in their application. They interest our intellectual faculties, and strongly impress our sentiments. The duty of adapting our conduct to them comes home to us with the authority of a mandate from God. While we confine ourselves to recommendations to beware of damp, to observe temperance, or to take exercise, as mere acts of prudence, without showing that God has pre-ordained certain painful consequences to follow from neglect, the injunction is addressed to only two or three faculties,-cautiousness, for instance, and self-love, in him who receives it. But if we are instructed in the constitution of the physical world, and

of our organism,-in the uses of the different parts of the human body, and the conditions of their healthy action,-in the causes of their derangement, and the pains consequent thereon, the intellect becomes deeply interested in the matter; and if the obligation to comply with these conditions be enforced on our moral and religious sentiments, as a duty imposed by the Creator, which we cannot neglect without suffering evil, then the motives to act in harmony with the physical and organic laws, as well as the power of doing so, will be greatly increased. Before we can dance well, not only must we know the motions, but our muscles must be trained to execute them; and in like manner, to enable us to act on precepts, not only must we comprehend their meaning, but our intellects and sentiments must be disciplined into the habit of actual performance. The work of acquiring and practically using scientific information concerning the natural world, its qualities, and their relations, is to the intellect and sentiments what dancing is to the muscles-it invigorates them; and as it is from them that obedience to the natural laws must spring, the exercise renders it easy and delightful.

It is only by comprehending the causes on which consequences depend, that we become thoroughly impressed with the invariableness of the physical and organic laws, acquire confidence in and respect for them, and fairly endeavour to accommodate our conduct to their operation. The human faculties are spontaneously active, and desire gratification; but the intellect must have fixed data on which to reason. A man in whom the faculties of constructiveness and weight are powerful, will naturally betake himself to constructing machinery; but if he be ignorant of the principles of mechanical science, he will not direct his efforts to such important ends, nor attain them with so much success, as if his intellect had been stored with this kind of knowledge. In like manner, a man may compose music by the impulses of the faculties of tune and time; but as there are immutable laws of harmony, he will not compose so correctly and in such good taste, if he be ignorant of them, as he would do if he knew them. In every art and science, there are principles referrible solely to the constitution of nature, which admit of countless applications. By following the laws of harmony, a musician may produce gay, grave, solemn, or ludicrous tunes, but he will never produce one good piece by violating them. While the farmers near Edinburgh allowed stagnant pools to deface their