An article in the May number of "Harpers' Magazine" presents drawings of a very simple arrangement by which any house can be made thoroughly self-ventilating. Ventilation, as this article shows, consists in two things,—a perfect and certain expulsion from the dwelling of all foul air breathed from the lungs or arising from any other cause, and the constant supply of pure air.

One source of foul air cannot be too much guarded against,—we mean imperfect gas-pipes. A want of thoroughness in execution is the sin of our American artisans, and very few gas-fixtures are so thoroughly made that more or less gas does not escape and mingle with the air of the dwelling. There are parlors where plants cannot be made to live, because the gas kills them; and yet their occupants do not seem to reflect that an air in which a plant cannot live must be dangerous for a human being. The very clemency and long-suffering of Nature to those who persistently violate her laws is one great cause why men are, physically speaking, such sinners as they are. If foul air poisoned at once and completely, we should have well-ventilated houses, whatever else we failed to have. But because people can go on for weeks, months, and years, breathing poisons, and slowly and imperceptibly lowering the tone of their vital powers, and yet be what they call "pretty well, I thank you," sermons on ventilation and fresh air go by them as an idle song. "I don't see but we are well enough, and we never took much pains about these things. There's air enough gets into houses, of course. What with doors opening and windows occasionally lifted, the air of houses is generally good enough";—and so the matter is dismissed.

One of Heaven's great hygienic teachers is now abroad in the world, giving lessons on health to the children of men. The cholera is like the angel whom God threatened to send as leader to the rebellious Israelites. "Beware of him, obey his voice, and provoke him not; for he will not pardon your transgressions." The advent of this fearful messenger seems really to be made necessary by the contempt with which men threat the physical laws of their being. What else could have purified the dark places of New York? What a wiping-up and reforming and cleansing is going before him through the country! At last we find that Nature is in earnest, and that her laws cannot be always ignored with impunity. Poisoned air is recognized at last as an evil,—even although the poison cannot be weighed, measured, or tasted; and if all the precautions that men are now willing to take could be made perpetual, the alarm would be a blessing to the world.

Like the principles of spiritual religion, the principles of physical religion are few and easy to be understood. An old medical apothegm personifies the hygienic forces as the Doctors Air, Diet, Exercise, and Quiet; and these four will be found, on reflection, to cover the whole ground of what is required to preserve human health. A human being whose lungs have always been nourished by pure air, whose stomach has been fed only by appropriate food, whose muscles have been systematically trained by appropriate exercises, and whose mind is kept tranquil by faith in God and a good conscience, has perfect physical religion. There is a line where physical religion must necessarily overlap spiritual religion and rest upon it. No human being can be assured of perfect health, through all the strain and wear and tear of such cares and such perplexities as life brings, without the rest of faith in God. An unsubmissive, unconfiding, unresigned soul will make vain the best hygienic treatment; and, on the contrary, the most saintly religious resolution and purpose may be defeated and vitiated by an habitual ignorance and disregard of the laws of the physical system.

Perfect spiritual religion cannot exist without perfect physical religion. Every flaw and defect in the bodily system is just so much taken from the spiritual vitality: we are commanded to glorify God, not simply in our spirits, but in our bodies and spirits. The only example of perfect manhood the world ever saw impresses us more than anything else by an atmosphere of perfect healthiness. There is a calmness, a steadiness, in the character of Jesus, a naturalness in his evolution of the sublimest truths under the strain of the most absorbing and intense excitement, that could come only from the one perfectly trained and developed body, bearing as a pure and sacred shrine the One Perfect Spirit. Jesus of Nazareth, journeying on foot from city to city, always calm yet always fervent, always steady yet glowing with a white heat of sacred enthusiasm, able to walk and teach all day and afterwards to continue in prayer all night, with unshaken nerves, sedately patient, serenely reticent, perfectly self-controlled, walked the earth, the only man that perfectly glorified God in his body no less than in his spirit. It is worthy of remark, that in choosing his disciples he chose plain men from the laboring classes, who had lived the most obediently to the simple, unperverted laws of nature. He chose men of good and pure bodies,—simple, natural, childlike, healthy men,—and baptized their souls with the inspiration of the Holy Spirit.

The hygienic bearings of the New Testament have never been sufficiently understood. The basis of them lies in the solemn declaration, that our bodies are to be temples of the Holy Spirit, and that all abuse of them is of the nature of sacrilege. Reverence for the physical system, as the outward shrine and temple of the spiritual, is the peculiarity of the Christian religion. The doctrine of the resurrection of the body, and its physical immortality, sets the last crown of honor upon it. That bodily system which God declared worthy to be gathered back from the dust of the grave, and re-created, as the soul's immortal companion, must necessarily be dear and precious in the eyes of its Creator. The one passage in the New Testament in which it is spoken of disparagingly is where Paul contrasts it with the brighter glory of what is to come: "He shall change our vile bodies, that they may be fashioned like his glorious body." From this passage has come abundance of reviling of the physical system. Memoirs of good men are full of abuse of it, as the clog, the load, the burden, the chain. It is spoken of as pollution, as corruption,—in short, one would think that the Creator had imitated the cruelty of some Oriental despots who have been known to chain a festering corpse to a living body. Accordingly, the memoirs of these pious men are also mournful records of slow suicide, wrought by the persistent neglect of the most necessary and important laws of the bodily system; and the body, outraged and down-trodden, has turned traitor to the soul, and played the adversary with fearful power. Who can tell the countless temptations to evil which flow in from a neglected, disordered, deranged nervous system,—temptations to anger, to irritability, to selfishness, to every kind of sin of appetite and passion? No wonder that the poor soul longs for the hour of release from such a companion.

But that human body which God declares expressly was made to be the temple of the Holy Spirit, which he considers worthy to be perpetuated by a resurrection and an immortal existence, cannot be intended to be a clog and a hindrance to spiritual advancement. A perfect body, working in perfect tune and time, would open glimpses of happiness to the soul approaching the joys we hope for in heaven. It is only through the images of things which our bodily senses have taught us, that we can form any conception of that future bliss; and the more perfect these senses, the more perfect our conceptions must be.

The conclusion of the whole matter, and the practical application of this sermon, is:—First, that all men set themselves to form the idea of what perfect health is, and resolve to realize it for themselves and their children. Second, that with a view to this they study the religion of the body, in such simple and popular treatises as those of George Combe, Dr. Dio Lewis, and others, and with simple and honest hearts practise what they there learn. Third, that the training of the bodily system should form a regular part of our common-school education,—every common school being provided with a well-instructed teacher of gymnastics; and the growth and development of each pupil's body being as much noticed and marked as is now the growth of his mind. The same course should be continued and enlarged in colleges and female seminaries, which should have professors of hygiene appointed to give thorough instruction concerning the laws of health.

And when this is all done, we may hope that crooked spines, pimpled faces, sallow complexions, stooping shoulders, and all other signs indicating an undeveloped physical vitality, will, in the course of a few generations, disappear from the earth, and men will have bodies which will glorify God, their great Architect.