The long agitated question relative to lunar influence in the production and aggravation of diseases, appears to be ultimately decided in the affirmative. If the moon attenuates, perhaps we should rather say rarefies, by her action, the air which we breathe; if she also diminishes the weight and pressure, and changes frequently the temperature of the atmosphere around us, we are, on first principles, led to a belief, that, at least in feeble and valetudinary habits, she may, or rather that she must, occasionally produce deviations from health. The position, however, relative to lunar agency in the production and aggravation of diseases, rests not, at present, on a speculative basis. It has passed into a subject of actual observation. It is no longer, therefore, a matter of calculation, but a matter of fact.

Epilepsy, insanity, hemorrhages, and fevers, are influenced by the position and phases of the moon. Hence these diseases are most frequent in their attacks, as well as most violent in their paroxysms, about the full and change of that celestial luminary. That this is peculiarly the case with respect to hemopthisis (spitting of blood) we not only believe on the authority of Meade, Moseley, and others, but deliberately assert from our own observation. It will, on examination, satisfactorily appear, that a great proportion of the cases of that formidable disease, occurs when the moon is at or near to one of her siziges.

No man either of the present or of any preceding age, ap. pears to have prosecuted the subject of lunar influence with so much discernment, zeal and success, as Dr. Balfour, of the province of Bengal. That he might be the better prepared for the elucidation of this interesting question, that acute and indefatigable experimentalist denied himself the natural refreshment of sleep, in a degree almost incredible, during the period of an entire lunation. For the space of twenty-eight days, he most assiduously observed the state of his barometer, watched all its variations, and, at the end of every thirty minutes, noted down the elevation of the mercury with his own hand-an instance of persevering voluntary wakefulness unexampled, as far as we are informed, in the whole history of human nature.

The result of this enterprize in science was, the discovery of lunar tides in the atmosphere, as distinct and regular, as those

that occur in the waters of the ocean. The existence of these tides had been previously suspected, and had oftentimes constituted a subject of speculation; but it was reserved for Dr. Balfour to demonstrate their reality. It was particularly his fortune to show, that the atmospheric tides, analogous to those of the ocean, attain their maximum at the periods of the full and change of the moon. At these times they are spring-tides, assuming the character of neap-tides on all other occasions. Our enlightened author further discovered between these atmospheric fluctuations and the access, paroxysms and termination of fevers, a very close and striking coincidence-a coincidence, amounting, in his estimation, to satisfactory proof, that the phenomena in question were related to each other as cause and effect. Hence he considered, apparently with perfect truth and justice, the agency of the moon in the production of diseases definitively established.

Were we inclined to dwell on the subject, a variety of well attested facts might be further adduced, in favour of the doctrine of lunar influence.

Fishermen are perfectly familiar with the effects of the moon on most kinds of shell-fish. They know, and have long known, that these aquatic animals are more full, juicy and fat, and consequently more delicious as articles of food, during the increase, than they are during the decrease of that luminary.

This fact was well known to the epicures of ancient Rome. Hence, says Lucilius, the poet,

"Luna alit ostrea, et implet echinos, muribus fibros
Et pecudi addit-

Hence, also, Manilius, a later poet, observes,

Si submersa fretis, concharum et carcere clausa,

Ad lunæ motum variant animalia corpus.

Horace has furnished us with his ideas on this subject, in the following line:

"Lubrica nascentes implent conchylia lune."

These observations we have thought it expedient to premise,

by way of introduction to what constitutes the leading subject of this article. Our object is to familiarize to the mind of the reader the general idea of the influence of the heavenly bodies. on the globe we inhabit-to convince him, that this influence is not one of those idle fancies which haunt the imagination of a visionary system-builder; but a substantial reality, palpable to the senses of every observer. If we have said nothing of the influence exercised on our earth by Mercury, Venus, Mars, and her other sister planets, it is not because we disbelieve in its existence. Self-balanced as the solar system is acknowledged to stand, it follows of necessity, that there must subsist an intercommunity of influence and action between all the bodies of which it is composed-between the earth and the other primary planets, no less than between the earth and the sun. Strike from this system any one of its main constituent parts, and although it might not be literally true, that, in the words of the poet, "planets and stars" would then "rush lawless through the sky," yet there can, we think, be no doubt, that very material changes would ensue in the economy of all its remaining bodies.

We now feel ourselves prepared for a statement of a few of the facts and arguments by which we conceive a belief in the influence of comets to be supported.

We shall consider this subject in a twofold point of viewas a philosophical inference; and, as a historical fact—a result on which we have strong ground to calculate, from our knowledge of the laws and principles of nature; and an event which has already occurred, and been recorded by the hand of the faithful historian.

In attempting to establish the agency of comets as a philosophical inference, we would observe, that the sun extends his influence to our earth through a twofold medium, his rays of heat and light, and his powers of attraction. The moon affects us principally by means of her attraction alone. The influence of her light on the economy of our globe, although distinctly perceptible, is, perhaps, too feeble to be embraced in the present calculation. By the term attraction we here understand, that universal, yet unknown power in nature, by which one distant body is capable of acting on another. Speaking in general

terms, the effect produced is in proportion to the distance and magnitude of the attracting bodies.

Most comets that visit the solar system being spheres of stupendous magnitude, possess attraction in common with the sun and moon-less powerful, indeed, than the former, but much more so than the latter of these celestial bodies. When within the confines of our system, then, it is neither unreasonable nor extravagant, but on the other hand consistent with the soundest analogy, to conclude, that these vast orbs extend their attraction to the earth. Although far more distant from us than the moon, the difference is counterbalanced by the superiority of their bulk, some of them being tenfold the size of that satellite. The moon, however, is acknowledged to affect very powerfully both the ocean and the atmosphere, and even to manifest. her influence on the solid earth, in the production of volcanoes, and, perhaps, of earthquakes.* What is there, then, to prevent comets from acting on our globe in a similar manner? We contend that, as far as human knowledge extends, there appears nothing to prevent them. On the other hand, all analogy is in favour of the belief, that such is, in reality, the extent of their action. Nor is it, indeed, on analogy alone, that we rest the doctrine of the existence of a reciprocal influence between comets and our earth. The fact is established by astronomic calculation. The comet of 1770 is known to have been retarded in its progress the space of two entire days by the attraction of the earth. But as attraction between bodies is reciprocal, it follows of necessity that the earth must, at the same time, have very sensibly felt the influence of the comet.

It is further known that, by the attraction of Saturn, the celebrated comet of 1759 was retarded in its progress 100, and by that of Jupiter 511 days. These facts incontestibly establish the existence of an intercommunity of action between comets and the primary planets of the solar system.

* It will be found, by a comparison of dates, that most earthquakes and eruptions of volcanoes that appear on record, have occurred about the full or change of the moon. The late earthquake commenced on the 16th, and the moon had changed on the 15th, of last December.

As a philosophical inference, then, the agency of comets on our globe, appears to rest on tenable ground.

In our estimation, however, the doctrine is still more completely defensible, when considered in the light of a historical fact. If we examine the history of memorable events in the physical world, from the earliest ages to the present period, we shall find, that as often as comets have appeared in the heavens, unusual phenomena have been prevalent on earth. Striking irregularities in the seasons, and even in the general economy of our globe, have been the constant concomitants of the passage of these bodies through the solar system. Among these irregu larities may be enumerated, earthquakes, eruptions of volcanoes, hurricanes, hail-storms, inundations, excessive droughts, violent extremes of heat and cold, famine, pestilence, and other epidemic diseases. We speak not extravagantly in asserting, that a detail of the numerous facts we possess in proof of this position, instead of an article like the present, would fill up a volume.

Our knowledge of the history of comets, and their apparent influence on the economy of our globe, extends to a period anterior to the commencement of the christian era.

In the year of Rome 607, being one hundred and forty-seven years before the birth of Christ, a comet made its way into the solar system, remarkable for its magnitude and brilliancy, and, probably, also for its proximity to the earth. Seneca remarks, that its aspect was fiery and red, and its coma or tail so signally luminous, as to dissipate, in a great measure, the darkness of the night. Its approach was rendered memorable by a train of the most dismal elementary convulsions, accompanied by a pestilence, which, in Numidia, Carthage and Utica alone, swept off upwards of a million of souls.

About one hundred and twenty-five years before the commencement of the christian era, being the first year of the reign of Mithridates king of Pontus, another very remarkable comet appeared in the heavens. "Septuaginta diebus, says Justin, ita luxit, ut cœlum omne flagrare videbatur," for seventy days it shone with such a lustre, that the whole heaven appeared to be on fire.