i I- 
 
 I 
 
f 
 
 ^r 
 
OUTLINES 
 
 OF 
 
 A MECHANICAL THEORY OF STORMS, 
 
 CONTAINING 
 
 THE TRUE LAW OF LUNAR INFLUENCE, 
 
 WITH 
 
 PRACTICAL INSTRUCTIONS TO THE NAVIGATOR, TO ENABLE HIM APPROX- 
 IMATELY TO CALCULATE THE COMING CHANGES OF THE 
 WIND AND WEATHER, FOR ANY GIVEN DAY, 
 AND FOR ANY PART OF THE OCEAN. 
 
 BY T. BASSNETT. 
 
 H 6e 
 
 NEW YORK: 
 D. APPLETON & COMPANY, 
 
 346 & 348 BROADWAY, 
 
 AND 16 LITTLE BRITAIN, LONDON. 
 
 1854. 
 
.'-33 
 
 Entered, according to Act of Congress, in the year 1853, by 
 
 T. BASSNETT, 
 In the Clerk's Office of the Southern District of New York. 
 
 d'FTOF 
 ancron 
 
CONTENTS, 
 
 SECTION FIRST. 
 
 Present State of the Science of Meteorology Primordial Con- 
 dition of the Solar System Theory of Gravitation the great 
 key of Nature Bessell's doubts of its perfect adequacy the 
 Newtonian Vacuum : its difficulties Nature of the element 
 called Ether The Medium of Space and the Electric Fluid 
 Ponderosity of Matter Dynamical law of Equilibrium Spe- 
 cific heat and its relation to space A Plenum not opposed to 
 Gravitation The medium of space in motion Formation of 
 Vortices A new principle developed Elements of the prob- 
 lem Button's theory of the production of rain Indications 
 of change and the cause Action of the Ethereal Current 
 Physical process of Atmospheric Derangement Redfield's the- 
 ory of Storms : its difficulties All storms are of brief dura- 
 tion and limited extent , . 13 
 
 SECTION SECOND. 
 
 Mechanical action of the Moon The Moon's mass Axis of the 
 Terral Vortex affected by the Moon: its inclination and posi- 
 tion : its displacement An example of the principle Correc- 
 tions necessary Milwaukie storm New York storm Ottawa 
 storm Liverpool storm Names and recurring order of the 
 storm-producing agents Record of the weather Second New 
 York storm 68 
 
 86I 
 
CONTENTS. 
 
 SECTION THIRD. 
 
 Lunar influence rejected by the learned Their conclusions not 
 valid Modifying causes in accordance with these principles 
 Years and seasons vary in character Superficial temper- 
 ature of different Planets No storms on the planet Mars Ro- 
 tation the cause of Ocean and Atmospheric Currents Press- 
 ure of the atmosphere and its regular and irregular variations 
 Terrestrial Magnetism Internal Constitution of the Globe 
 Magnetic variations Cause of these variations Magnetic 
 storms Aurora Borealis : its altitude Earthquakes : their pos- 
 sible connection with Storms. . . 101 
 
 SECTION FOURTH. 
 
 The solar spots Law of periodicity compared with the theo- 
 ry Existence of another planet beyond Neptune probable 
 Masses of the Sun and Planet yet uncertain The Law of Grav- 
 itation not above suspicion Proofs of this The full of the 
 Moon Density of the Ethereal Medium : its law in the Solar 
 Vortex Bode's law of the planetary distances Law of plan- 
 etary density Law connecting the present and former diame- 
 ters of the planets Disturbing action of the Ether Kepler's 
 third law not rigidly exact Inconsistencies of Astronomers 
 Nature of light and heat Distinction between light and heat. 147 
 
 SECTION FIFTH. 
 
 Comets Their small inclinations Their motions chiefly di- 
 rect Comet of 1770 and 1844 Cause of acceleration in the 
 case of Encke Anomalous motions of the comet of 1843 
 Change of diameter at different distances of a comet from the 
 sun Cause of this change Nature of the-nebulosity Form- 
 
CONTENTS. V 
 
 ation of the tail Compound nature of a comet's light mo- 
 tion and direction of a comet's tail Phenomena presented by 
 the great comet of Halley Mass of a comet The Zodial 
 light Nebulous stars Shooting stars Periodic showers Pe- 
 riodicity doubtful Cause of the apparent periodicity Cause 
 for being more numerous in Autumn than in Spring. . . 187 
 
 SECTION SIXTH. 
 
 State of the polar ice since 1845 Sir John Franklin's track 
 Probable existence of islands north of Behring's Straits Pos- 
 sibility of subsisting in the Arctic islands News from the In- 
 vestigator Necessity of searching in a higher latitude than 
 the Investigator visited Franklin's misfortunes due to Scien- 
 tific Errors Relative levels of the Atlantic and Pacific Oceans 
 The Arctic seas more accessible in a few years Conclusion. 288 
 
PEEP ACE. 
 
 ON presenting to the public a work of this novel 
 character, overstepping, as it does, the barriers erected 
 by modern systems to the further progress of knowl- 
 edge, a few words of explanation may not be inappro- 
 priate. Early imbued with a desire to understand the 
 causes of natural phenomena, the author devoured with 
 avidity the interpretations contained in the elementary 
 works of orthodox science, until reason and observation 
 rendered him dissatisfied with the repast. To him it 
 appeared that there was an evident tendency in scho- 
 lastic instruction, to make the knowledge of nature in- 
 accessible to the many, that the world might be made 
 more dependent on the few ; while many of the estab- 
 lished principles, on which the learned rested, seemed to 
 be at variance with the simplicity and consistency of 
 truth. Thus situated, he ventured to think for himself, 
 and looking back on the history of the past, and finding 
 so many cases in which the philosophy of to-day was 
 supplanted by a different system on the morrow, he was 
 led to suspect the possibility of future revolutions, and 
 was thus determined to be no longer embarrassed by 
 previous systems, nor deterred by opinions however 
 
Vlll PEEFACE. 
 
 learned, which conflicted with a rational recognition of 
 the mechanical nature of all physical phenomena. 
 
 The science of meteorology, to which the following 
 pages are devoted, is, and always has been, a confessedly 
 complex subject ; and on this account, any suggestions 
 and facts which observation gleans, no matter how 
 humble the source may be, should not be denied a 
 hearing by those professedly engaged in the pursuit of 
 truth. Step by step, the author became more and more 
 confirmed in his doubts o the soundness of many 
 modern theories ; and in 1838 he had attained a posi- 
 tion which enabled him to allege in the public prints of 
 the day, that there did exist certain erroneous dogmas 
 in the schools, which stood in the way of a fuller de- 
 velopment of the causes of many meteorological pheno- 
 mena. This annunciation was made in general terms, 
 and no notice was taken of it. Subsequently, he for- 
 warded to the British Association of Science, then con- 
 vened at Birmingham, a communication of similar tenor ; 
 and at a later date still, a more particular statement of 
 the advantages of his discoveries to the navigator and 
 agriculturist, was sent to the British admiralty. The 
 first of these communications was treated with silent 
 contempt ; the last elicited some unimportant reply. 
 In 1844 a memorial was presented to Congress, accom- 
 panied with a certified copy of predictions of the 
 weather, written several weeks before the event, and 
 attested in due form by two impartial witnesses ; but 
 neither did this result in any inquiry as to its truth. 
 During the time since elapsed, he has been engaged in 
 pursuits which prevented him from pressing the subject 
 elsewhere, until the spring of 1853, he brought his 
 
PREFACE. ix 
 
 theory under the notice of the Smithsonian Institution. 
 This led to a correspondence between himself and the 
 gentlemanly Secretary of the Institution, whose doubts 
 of the truth of his allegations were expressed with kind- 
 ness, and whose courtesy was in strange contrast with 
 the conduct of others. In the communications which 
 he forwarded to that Institution, he gave a detailed 
 statement of the difficulties he had met with, and ex- 
 pressed the hope that an Institution, created for the 
 purpose of increasing and diffusing knowledge, would 
 feel justified in lending the influence of its name to 
 facilitate the completion of a theory which was yet un- 
 deniably imperfect. In view of this, a test was pro- 
 posed. * " Give us, for example, a prediction of the 
 weather for one month in each season of the year 1854, 
 for the City of Washington." This test the author re- 
 fused, for the reason that he did not consider it neces- 
 sary to wait so long ; but he informed the Secretary of 
 the Institution, that he would prepare an outline of his 
 theory, which would enable him to decide upon the 
 merits of the discoveries claimed. This outline is con- 
 tained in the following pages. During the summer of 
 1853 he called upon Professor Henry, then at Chicago, 
 with his manuscript; but a sudden indisposition pre- 
 vented that gentleman from having it read. He, how- 
 ever, strongly recommended its publication from such 
 impressions he then received.f This the author had 
 
 * Extract from a letter from Professor Henry. 
 
 f This gentleman kindly offered to contribute from his own private 
 means, to forward the publication, but he could do nothing officially 
 without submitting the manuscript to three different censors. He who 
 claims a new discovery, will seldom be satisfied to have it judged by 
 
 1* 
 
X PREFACE. 
 
 resolved on, from a sense of duty to the world at large, 
 although the promise was rather of prospective loss than 
 of present benefit. The peculiar form under which the 
 theory appears, is, therefore, a result of the circum- 
 stances above stated, and of the author's present inabil- 
 ity to enter into the minute details of a subject, which 
 embraces in its range the whole visible creation. 
 
 In extending the theory to other phenomena, he has 
 only fearlessly followed out the same principles which 
 have conducted him to a knowledge of a disturbing 
 cause, to which atmospheric storms owe their origin, 
 and in doing so he has conferred with no one. For 
 whatever of merit or of blame may therefore justly 
 attach to these views, he alone is responsible. If he 
 has charged the scientific with inconsistency, or with 
 sometimes forgetting that the truth of their unneces- 
 sarily abstruse investigations depends on the truth of 
 the data, he at least is conscientious ; for he is too well 
 aware that to provoke an unfavorable verdict by con- 
 tending against such fearful odds, is not the surest way 
 to either wealth or fame, or even to an acknowledgment 
 of at least the mite, which he cannot but feel that he has 
 contributed to the treasury of knowledge. That the 
 scientific organizations of the day do tend to curb the 
 aberrations of a fanciful philosophy, cannot be denied ; 
 
 men who are engaged in the same investigations, however pure and 
 honorable they may be. Is this Institution adopting the best plan of 
 aiding truth, in its struggles against error? Should any man sit as 
 judge in his own trial ? If there had been a powerful Institution to 
 stand between Galileo and the scientific of his day, his doctrines would 
 not have been condemned, and the world would have been fifty years 
 more in advance. 
 
PREFACE. xi 
 
 but at the same time there is engendered such a slavish 
 subordination as checks the originality of thought, and 
 destroys that perfect freedom from the trammels of sys- 
 tem, so necessary to success in the pursuit of truth. Of 
 such an influence the author explicitly asserts his entire 
 independence. 
 
 In thus introducing his theory, the reader is fore- 
 warned that he will not find it dressed in the fascinating 
 garb of the popular literature of the day, whose chief 
 characteristic is to promise much when possessing little. 
 It is, however, a plant of the author's own raising, un- 
 propped, unpruned, with none of the delicate tendrils 
 or graceful festoons of the trellissed vine ; yet he flat- 
 ters himself that its roots are watered by the springs of 
 truth, and hopes that he who is in quest of that, will not 
 find, amidst its many clusters, any fruit to set his teeth 
 on edge. 
 
MECHANICAL THEORY OF STORMS, 
 
 SECTION FIEST. 
 
 PRESENT STATE OF METEOROLOGY. 
 
 THE present state of the science of which we are about to 
 treat, cannot be better defined than in the words of the cele- 
 brated Humboldt, who has devoted a long life to the investiga- 
 tion of this department of Physics. He says : " The processes 
 of the absorption of light, the liberation of heat, and the vari- 
 ations in the elastic and electric tension, and in the hygrometric 
 condition of the vast aerial ocean, are all so intimately connected 
 together, that each individual meteorological process is modified 
 by the action of all the others. The complicated nature of 
 these disturbing causes, increases the difficulty of giving a full 
 explanation of these involved meteorological phenomena ; and 
 likewise limits, or wholly precludes the possibility of that pre- 
 determination of atmospheric changes, which would be so im- 
 portant for horticulture, agriculture, and navigation, no less than 
 for the comfort and enjoyment of life. Those who place the 
 value of meteorology in this problematic species of prediction, 
 rather than in the knowledge of the phenomena themselves, are 
 firmly convinced that this branch of science, on account of 
 which so many expeditions to distant mountainous regions have 
 been undertaken, has not made any very considerable progress for 
 
14 " .f^iCHANK^ .T35ORY OF STORMS. 
 
 centuries p$tt L ^ The' fe^tifiden^^ which they refuse to the phys- 
 icist they yield 'to chartges of the moon, and to certain days 
 marked in the calender by the superstition of a by-gone age." 
 
 The charge thus skilfully repelled, contains, however, much 
 truth ; there has been no adequate return of the vast amount of 
 labor and expense thus far devoted to this branch of knowledge. 
 And it is not wonderful that the popular mind should expect a 
 result which is so much in accordance with the wants of man- 
 kind. Who is there whose happiness, and health, and comfort, 
 and safety, and prosperity, may not be more or less affected by 
 reducing to law, the apparently irregular fluctuations of the 
 weather, and the predetermination of the storm ? To do this 
 would be the crowning triumph of the age ; and the present 
 theory has pioneered the way for its speedy accomplishment. 
 
 ORIGINAL CONDITION OF THE EARTH. 
 
 That the present order of things had a beginning, is taught 
 by every analogy around us, and as we have the glaring fact 
 forced upon us, that our globe has experienced a far higher 
 temperature on its surface than obtains at present, and more- 
 over, as it is demonstrated beyond a cavil, that the interior is 
 now of far higher temperature than is due to solar radiation, 
 we are justified in concluding, not only that the condition of 
 the interior of our globe is that of fusion, but that its original 
 temperature was far higher than at present ; so that the inference 
 is allowable that there has been a time when the whole globe 
 was perhaps in this state. But why should we stop here? 
 There are three states of matter, the solid, the fluid, and the 
 gaseous ; and with this passing glance at the question, we will 
 jump at once to the theory of La Place, that not only our 
 own globe, but the whole solar system, has been once in the neb- 
 ulous state. 
 
 In justice to himself, the author ought to remark, that he 
 
MECHANICAL THEORY OF STORMS. 15 
 
 had reasoned his way up to this starting point, before even the 
 name of La Place had reached his ears. He makes the remark 
 in order to disclaim any desire to appropriate that which belongs 
 to another ; as he may innocently speak of things hereafter, 
 the idea of which has occurred to others. It is not his intention 
 here to say a word pro or con on the nebular hypothesis ; it is 
 sufficient to allude to the facts, that the direction of rotation 
 and of revolution is the same for all the planets and satellites 
 of our system ; and that the planes on which these motions are 
 performed, are nearly coincident. That this concordance is due 
 to one common cause, no one acquainted with the theory of 
 probabilities will pretend to deny. 
 
 GREAT OBJECT OF LA PLACE. 
 
 The science of Astronomy occupies a pre-eminent rank in the 
 physical circle, not only on account of that dignity conferred 
 upon it in the most remote antiquity, or as being the grand 
 starting point the earliest born of science from whence we 
 must contemplate the visible creation, if we would reduce its 
 numerous details into one harmonious whole ; but also on ac- 
 count of its practical fruits, of the value of which modern com- 
 merce is an instance. Accordingly we will glance at its past 
 history. In the earliest ages there was no doubt a rational 
 view entertained of the movements of the planets in space. 
 From the Chaldeans to the Arabs, a belief prevailed, that space 
 was filled with a pure ethereal fluid, whose existence probably 
 did not rest on any more solid foundation than analogy or tra- 
 dition. One hundred years after Copernicus had given to the 
 world the true arrangements of our planetary system, Descartes 
 advanced his theory of vortices in the ethereal medium, in which 
 the planets were borne in orbits around the sun, and the satel- 
 lites around their primaries. This idea retained its ground 
 with various additions, until the Geometry of Newton recon- 
 
16 MECHANICAL THEORY OF STORMS. 
 
 ciled the laws of Kepler with the existence of a power pertain- 
 ing to matter, varying inversely as the squares of the distances, 
 to which power he showed the weight of terrestial bodies was 
 owing,, and also the revolution of the moon about the earth. 
 Since Newton's day, those deviations from the strict wording of 
 Kepler's laws, have been referred to the same law, and the 
 avowed object of the author of the " Mechanique Celeste," was 
 to bring all the great phenomena of nature within the grasp of 
 analysis, by referring them to one single principle, and one sim- 
 ple law. And in his Introduction to the Theory of the Moon, 
 he remarks : " Hence it incontestibly follows, that the law of 
 gravitation is the sole cause of the lunar inequalities." 
 
 BESSEL'S OPINION. 
 
 However beautiful the conception, it must be admitted that in 
 its a priori aspect, it was not in accordance with human expe- 
 rience and analogy to anticipate a successful issue. In nature 
 law re-acts upon law, and change induces change, through an 
 almost endless chain of consequences ; and it might be asked, 
 why a simple law of matter should thus be exempt from the 
 common lot ? Why, in a word, there should be no intrinsic 
 difference in matter, by which the gravitation of similar or dis- 
 similar substances should be affected ? But experiment has de- 
 tected no such differences ; a globe of lead and a globe of wood, 
 of equal weight, attract contiguous bodies with equal force. It 
 is evident, therefore, that if there be such differences, human 
 means are not yet refined enough to detect them. Was the 
 issue successful then ? Generally speaking, we may say yes. 
 But where there is a discrepancy between theory and observa- 
 tion, however small that may be, it shows there is still something 
 wanting ; and a high authority (Professor Bessel) says in re- 
 lation to this : " But I think that the certainty that the theory 
 based upon this law, perfectly explains all the observations, is 
 
MECHANICAL THEORY OF STOEMS. 17 
 
 not correctly inferred." We will not here enumerate the cases 
 to which suspicion might be directed, neither will we more than 
 just allude to the fact, that the Theory of Newton requires a 
 vacuum, in order that the planetary motions may be mathe- 
 matically exact, and permanent in their stability. 
 
 A VACUUM REQUIRED BY MODERN SYSTEMS. 
 
 Whatever may be the practical belief of the learned, their 
 fundamental principles forbid the avowal of a plenum, although 
 the undulatory theory of light renders a plenum necessary, and 
 is so far virtually recognized by them, and a correction for re- 
 sistance is applied to the Comet of Encke. Yet there has been 
 no attempt made to reconcile these opposing principles, other 
 than by supposing that the celestial regions are filled with an 
 extremely rare and elastic fluid. That no definite view has been 
 agreed on, is not denied, and Sir John Herschel speculates on 
 the reality of a resisting medium, by suggesting questions that 
 will ultimately have to be considered, as : " What is the law of 
 density of the resisting medium which surrounds the sun ? Is 
 it in rest or in motion ? If the latter, in what direction does it 
 move ?" In these queries he still clings to the idea of Encke, 
 that the resistance is confined to the neighborhood of the sun 
 and planets, like a ponderable fluid. But the most profound 
 analyst the world has ever boasted, speaks less cautiously, 
 (Poisson Rech.) " It is difficult to attribute, as is usually done, 
 the incandescence of aerolites to friction against the molecules 
 of the atmosphere, at an elevation above the earth where the 
 density of the air is almost null. May we not suppose that the 
 electric fluid, in a neutral condition, forms a kind of atmosphere, 
 extending far beyond the mass of our atmosphere, yet subject to 
 terrestrial attraction, yet physically imponderable, and, conse- 
 quently, following our globe in its motion ?" The incandescence 
 of aerolites must, therefore, be owing to friction against the 
 
18 MECHANICAL THEORY OF STOEMS. 
 
 molecules of the electric fluid which forms an atmosphere around 
 the globe. According to this view, some force keeps it there, 
 yet it is not ponderable. As it is of limited extent, this is not 
 the medium whose undulations brings to light the existence of 
 the stars ; neither is Encke's, nor Herschel's, nor any other re- 
 sisting medium. Where shall we find the present established 
 principles of science ? If we grant the Newtonians a plenum, 
 they still cling to attraction of all matter in some shape. If we 
 confine them to a vacuum, they will virtually deny it. Is not 
 this solemn trifling ? How much more noble would it be to 
 exhibit a little more tolerance, seeing that they themselves 
 know not what to believe ? We do not offer these remarks as 
 argument, but merely as indications of that course of reasoning 
 by which we conclude that the upholders of the present systems 
 of science are not entitled to any other ground than the pure 
 Newtonian basis of an interplanetary vacuum. 
 
 DIFFICULTIES OF THIS VIEW. 
 
 This, then, is the state of the case : Matter attracts matter di- 
 rectly as the mass, and inversely as the squares of the distances. 
 This law is derived from the planetary motions ; space is, con- 
 sequently, a void ; and, therefore, the power which gives me- 
 chanical momentum to matter, is transferred from one end of 
 creation to the other, without any physical medium to convey 
 the impulse. At the present day the doctrines of Descartes are 
 considered absurd ; yet here is an absurdity of a far deeper 
 dye, without we resort to the miraculous, which at once oblit- 
 erates the connection between cause and effect, which it is the 
 peculiar province of physical science to develop. Let us take 
 another view. The present doctrine of light teaches that light 
 is an undulation of an elastic medium necessarily filling all 
 space ; and this branch of science probably rests on higher and 
 surer grounds than any other. Every test applied to it by the 
 
MECHANICAL THEORY OF STORMS. 19 
 
 refinements of modern skill, strengthens its claims. Here then 
 the Newtonian vacuum is no longer, a void. If we get over 
 this difficulty, by attributing to this medium a degree-of tenuity 
 almost spiritual, we shall run upon Scylla while endeavoring to 
 shun Charybdis. Light and heat come bound together from 
 the sun, by the same path, and with the same velocity. Heat 
 is therefore due also to an excitement of this attenuated medium. 
 Yet this heat puts our atmosphere in motion, impels onward 
 the waves of the sea, wafts our ships to distant climes, grinds 
 our corn, and in various ways does the work of man. If we ex- 
 pose a mass of metal to the sun's rays for a single hour the 
 temperature will be raised. To do the same by an artificial 
 fire, would consume fuel, and this fuel would generate the 
 strength or force of a horse. Estimate, therefore, the amount 
 of force received from the sun in a single day for the whole 
 globe, and we shall find that nothing but a material medium 
 will suffice to convey this force.* 
 
 Let us appeal to analogy. The undulations of our atmos- 
 phere produce sound ; that is, convey to he ear a part of a me- 
 chanical force imparted to a solid body a bell for instance. 
 Let us suppose this force to equal one pound. On account of 
 the elasticity of the bell, the whole of the force is not instanta- 
 neously imparted to the surrounding air ; but the denser the 
 air the sooner it loses its motion. In a dense fluid like water, 
 the motion is imparted quickly, and the sound is not a ring but 
 a click. If we diminish the density of the air, the loss of mo- 
 tion is retarded ; so that we might conceive it possible, provided 
 the bell could be suspended in a perfect vacuum, without a me- 
 chanical tie, and there was no friction to overcome from the 
 rigidity of its particles, that the bell would vibrate forever, al- 
 though its sound could never reach the ear. We see, therefore, 
 that the mechanical effect in a given lime, is owing to the 
 density of the medium. But can we resort to such an analogy ? 
 Every discovery in the science confirms more and more the 
 
20 MECHANICAL THEORY OF STOEMS. 
 
 analogy between the motions of air and the medium of space ; 
 the angle of reflexion and incidence follows the same law in both ; 
 the law of radiation and interference ; and if experiments were 
 instituted, there can be but little doubt that sound has also got its 
 spectrum. 
 
 ETHER IMPONDERABLE. 
 
 The medium of space, therefore, is capable of conveying a me- 
 chanical force from one body to another ; it therefore possesses 
 inertia. Does it also possess gravity ? If we forsake not the 
 principles of science, it is but right that we expect science shall 
 abide by her own principles. Condensation in every elastic 
 medium is as the compressing power, according to all experi- 
 ments. In the case of our atmosphere under the law of gravi- 
 tation, the density of air, (supposing it to be infinitely expan- 
 sible,) at a height only of ten semidiameters of the earth above 
 its surface, would have only a density equal to the density of 
 one cubic inch of such air we breathe, if that cubic inch was to be 
 expanded so as to fill a globular space whose centre should be 
 the earth, and whose surface should take inside the whole vis- 
 ible creation. Such a medium could convey no mechanical 
 force from the sun, and therefore the medium of space cannot 
 be ponderable. Simple as the argument is, it is unassailable. 
 
 ELECTRIC FLUID THE MEDIUM OF SPACE. 
 
 Let us take yet another view. All experiments prove that 
 the phenomenon we call electricity, is owing to a disturbance of 
 the equilibrium or natural condition of a highly elastic fluid. 
 In certain conditions of the atmosphere, this fluid is accumulated 
 in the region of the clouds, and by its tension is enabled to force 
 a passage through opposing obstacles, in order to restore the 
 equilibrium. By experiment it is found that dry dense air op- 
 poses the greatest obstacle to its escape. As the air is rarefied, 
 
MECHANICAL THEORY OF STORMS. 21 
 
 this obstacle diminishes, until in a vacuum the transmission may be 
 considered instantaneous. There ought to be, therefore, a greater 
 escape of electricity from the clouds upwards than downwards ; 
 and, if space be void, or only filled with an extremely attenuated 
 matter, the electricity of the earth, considered as an elastic fluid 
 without ponderosity, (and no law of condensation from the law 
 of gravity in harmony with its other attributes, will allow us to 
 consider it otherwise,) would long since have left the earth. The 
 same objection applies in the case of the galvanic and magnetic 
 fluids. If we entertain the idea that electricity is a mere dis- 
 turbance of natural condition, wherein two fluids are united, and 
 that an excess of one is necessarily attended by deficiency in the 
 other, we depart from the first rule of philosophy, which teaches 
 us to admit no greater number of causes than are sufficient to 
 explain the phenomenon. For we fearlessly assert that not a 
 single fact exists in electrical science, which can be explained 
 better on Dufoy's theory than on Franklin's ; and the former ob- 
 jections would still apply. 
 
 NEWTONIAN GRAVITY. 
 
 But what is gravity ? According to Newton : " Haec est 
 qualitas omnium in quibus experimenta instituere licet, et prop- 
 terea per Reg. 3 de universes affirmanda est." Vide Prin. Lib. 
 Ter. Cor. 2. Prop. vi. 
 
 Now the other primary qualities of matter are unaffected by 
 circumstances. The inertia of a particle of matter is the same 
 at Jupiter as on the earth, so also is its extension ; but not so 
 with gravity. It depends on other matter, and on its distance 
 from it ; and may be less or greater at different times, and in 
 different places. It is, therefore, not philosophical to say that 
 all matter is necessarily ponderous, inasmuch as it is a virtue 
 not residing in itself alone, but needs the existence of other 
 matter to call it into action. If an atom were isolated in space 
 
22 MECHANICAL THEORY OF STORMS. 
 
 it would have no weight. If influenced by other matter, there 
 must be some physical medium to convey the influence, or 
 gravity is not in accordance with the laws of force and motion. 
 Which horn of the dilemma shall we take ? Let us first admit 
 that there is a principle of gravitation, affecting all planetary or 
 atomic matter, and that there exists a highly elastic medium, 
 pervading all space, conveying to us the light of the most dis- 
 tant stars, and that this medium is not aifected by gravity. In 
 this summary way, therefore, we have arrived at the pivot on 
 which this theory turns. 
 
 The prominent feature of the theory, therefore, is the neces- 
 sity it will show for the existence of an all-pervading medium, 
 and that it possesses inertia without ponderosity. That elec- 
 tricity is nothing more than the effects of the condensation and 
 rarefaction of this medium by force. That it also pervades all 
 atomic matter, whose motions necessarily move the medium ; 
 and, consequently, that there can be no motion without some 
 degree of electricity. That no change can take place in bodies 
 either by chemical decomposition, by increase or decrease of 
 temperature, by friction or contact, without in some measure ex- 
 citing electricity or motion of the ether. That galvanism and 
 magnetism are but ethereal currents without condensation, induced 
 by peculiar superficial and internal molecular arrangement of 
 the particles of certain substances. That light and heat are 
 effects of the vibrations of atoms, propagated through this uni- 
 versal medium from body to body. That the atomic motion 
 of heat can be produced by the motion of translation or mo- 
 mentum of bodies in the gross, that is, by friction, by com- 
 pression, &c. ; and can be reconverted into momentum at our 
 pleasure. Hence the latent heat or specific atomic motion of 
 combustibles, originally derived from the sun, is transferred to 
 atoms, which are capable of being inclosed in cylinders, so as to 
 make use of their force of expansion, which is thus converted 
 into momentum available for all the wants of man. 
 
MECHANICAL THEOEY OF STOEMS. 23 
 
 GRAVITY MECHANICAL. 
 
 When we come to a full examination of this theory, we shall 
 further reason that this ether, so far from being of that quasi 
 spiritual nature which astronomers would have us believe, is a 
 fearfully energetic fluid, possessing considerable inertia and 
 elasticity ; that its law of condensation is that of all other 
 fluids, that is, as the compressing force directly ; and that its 
 effects are simply a product of matter and motion. We will 
 next endeavor to prove that the gravity of planetary matter 
 could not exist without this ethereal medium, by showing that 
 it is an effect produced by the interference of opposing waves, 
 whereby a body is prevented from radiating into space its own 
 atomic motion, from the side opposite which another body is 
 placed, as much as on the opposite side, and consequently it is 
 propelled by its own motion towards the other body. And this 
 effect following the simple law of inertia and radiation, is di- 
 rectly as the mass, and inversely as the squares of the distances. 
 
 GREAT PRINCIPLE OF DYNAMICS. 
 
 One great principle to be kept in view in this investigation, 
 is that which teaches that the product of matter, angular ve- 
 locity, and distance from the centre of motion, must ever be a 
 constant quality in every balanced system. Yet this principle 
 does not seem to be observed in the case of the planets. We 
 will, however, endeavor to show that it is rigidly observed. 
 And we will extend the principle further, and contend that all 
 the phenomena of nature are consequences of the constant ten- 
 dency of matter to conform to this principle of equilibrium, 
 when suffering temporary derangement from the operation of 
 other laws. That throughout the system of nature, equal spaces 
 possess equal force. That what we call temperature, is nothing 
 more than the motion of equilibrium or atomic momentum of 
 
24: MECHANICAL THEORY OF STORMS. 
 
 space ; or, in other words, that if all space were fluid, and in a 
 state of equilibrium, the product of each atom of equal volume, 
 by its motion would be a constant quality. From this it would 
 seem to follow, that the specific heat of bodies should be in- 
 versely as their atomic weights ; and this does, no doubt, ap- 
 proximately obtain as was proved by Dulong and Petit, for 
 metallic substances, more recently by Regnault, and has since 
 been extended by Gamier to other substances. But it is to the 
 gaseous state that we must look for confirmation of the principle 
 that equal spaces possess equal power ; and in doing so, it will 
 be necessary to bear in mind, that the ether also is affected by 
 temperature. 
 
 SPECIFIC HEAT. 
 
 It has been contended by some that the medium which con- 
 veys the impression of light through transparent bodies, is 
 necessarily more dense within the body than without ; but ac- 
 cording to this theory the converse is true. A ray of light is a 
 mechanical impulse, propagated through an elastic medium, 
 and, like a wave in water, tends to the side of least resistance. 
 Within a refracting body the ether is rarefied, not only by the 
 proximity of the atoms of the body (or its density), but also by 
 the motions of those atoms ; so that if two simple gases of dif- 
 ferent specific gravity be made equal in density by compression, 
 their refraction will be approximately as their specific heats. 
 In the case of solids and liquids, or even compound gases, there 
 is a continual absorption of motion to produce the cohesion of 
 composition and aggregation. And the specific heats of com- 
 pound gases will be found greater than those of simple gases, 
 in proportion to the loss of volume by combination, ceteris 
 paribus. If impenetrability be a law of matter, the more a 
 portion of atomic matter is condensed, the less ether will be 
 found in the same space. The same is also true when the 
 natural density or specific gravity of a gas is greater than that 
 
MECHANICAL THEORY OF STORMS. 25 
 
 of another. And the lighter the gas, the more will this circum- 
 stance vitiate the experiments to determine its specific heat. 
 There is, therefore, this great source of fallacy in such experi- 
 ments, viz. : that the ether permeates all fluids and solids, and 
 that its specific heat probably far exceeds that of all other 
 matter. This is a fundamental position of the theory, in sup- 
 port of which we will introduce a fact announced by M. V. 
 Kegnault, which was published in the Comptes Renclus of the 
 French Academy for April, 1853. He says: "In the course 
 of my researches I have encountered, indeed, at every step, 
 anomalies which appeared to me inexplicable, in accordance 
 with the theories formally recognized. For the sake of illustra- 
 tion I will quote one instance : 1st, a mass of gas, under a 
 pressure of ten atmospheres, is contained in a space which is 
 suddenly doubled ; the pressure falls to five atmospheres. 2d. 
 Two reservoirs of equal capacity are placed in a calorimeter ; 
 the one is filled with a gas, under a pressure of ten atmospheres ; 
 the second is perfectly empty. In these two experiments, the 
 initial and final conditions of the gas are the same ; but this 
 identity of condition is accompanied by calorific results which 
 are very different ; for while in the former experiment there is 
 a reduction of temperature, in the second the calorimeter does 
 not indicate the slightest alteration of temperature." This ex- 
 periment tends to confirm the theory. In the first experiment, 
 the sudden doubling of the space causes the either also to ex- 
 pand, inasmuch as the sides of the vessel prevent the instantane- 
 ous passage of the external ether. In the second, both vessels 
 are full, one of ether, and the other of air mixed with ether ; so 
 that there is no actual expansion of the space, and consequently 
 no derangement of the quantity of motion in that space. 
 
 2 
 
26 MECHANICAL THEORY OF STORMS. 
 
 LAW OF SPECIFIC HEAT. 
 
 From this view it is evident that the specific heat of elastic 
 fluids can only be considered as approximately determined. If 
 equal spaces possess equal momenta, and the ethereal or tomic 
 matter be inversely as the weight of the atomic matter in the 
 same space, it follows that the product of the specific gravities 
 and specific heats of the simple gases should be constant ; or 
 that the specific heats should be inversely as the specific gravi- 
 ties, taking pound for pound in determining those specific 
 heats. If we. test the matter by the data now afforded, it is 
 best to obey the injunction, " In medio tutissimus ibis" In the 
 following table, the first column are the values obtained by 
 Reynault ; in the second, the former values ; and in the third, 
 the mean of the two. 
 
 Gases. Reg. specific heats. 
 
 Former epeciflc heat*. 
 
 Mean. 
 
 Atmospheric air, .237 
 
 .267 
 
 .252 
 
 Oxygen, .218 
 
 .236 
 
 .227 
 
 Nitrogen, .244 
 
 .275 
 
 .260 
 
 Hydrogen, 3.405 
 
 3.294 
 
 3.350 
 
 The specific gravities of these gases, according to the best 
 tables in our possession, are : 
 
 Specific gravities. Mean. Products. 
 
 Atmospheric air, 1.0000 X .252 = .252 
 
 Oxygen, 1.1111 X .227 = .252 
 
 Nitrogen, 0.9722 X .260 = .252 
 
 Hydrogen, 0.0745 X 3.350 = .249 
 
 As might be expected, there is a greater discrepancy in the 
 case of hydrogen. 
 
 If we test the principle by the vapor of water, we must con- 
 sider that it is composed of two volumes of hydrogen and one 
 volume of oxygen, and that one volume disappears ; or that 
 
MECHANICAL THEOKY OF STOEMS. 27 
 
 one-third of the whole atomic motion is consumed by the inter- 
 ference of the vibrations of the ether, necessary to unite the 
 atoms, and form an atom of water. We must therefore form 
 this product from its specific gravity and two-thirds of its 
 specific heat On no one subject in chemistry has there been 
 so much labor expended, as in determining the specific heat of 
 watery vapor. In relation to this, Regnault observes : " It is 
 important to remark that an immense number of experiments 
 have been made, to find the specific heat of steam, and that it 
 is about one-half of what it was thought to be." He gives its 
 value .475 ; but this is vitiated still, by the non-recognition of 
 the specific heat of the ether. Former experiments give .847. 
 Perhaps Regnault's numbers are entitled to the most weight. 
 Instead of taking the mean, therefore, we will give double 
 weight to his results ; so that we get .600 for the specific heat 
 of vapor, and as its specific gravity is .625, the product .400 X 
 .625 is .250, the same as for hydrogen. Little importance, 
 however, should be attached to such coincidences, owing to the 
 uncertainty of the numbers. If our position be correct, the 
 specific heat of hydrogen should be 16 times greater than of 
 oxygen. The atomic weights are as 1 to 8, while their volumes 
 are as 2 to 1 ; therefore, for equal spaces, the matter is as 1 to 
 16. Calling the specific heat 16 to 1, and taking the amount 
 due to half the space, the product becomes as 8 to 16; but in 
 the rarer gas there is 8 times as much ethereal momentum or 
 matter, which, added to the atomic matter, renders the spaces 
 equal.* Reynault's results give a ratio of specific heats = 1 to 
 = 1 to 15.6. 
 
 * The specific heat of the ether being a constant factor, it may be 
 divided out. 
 
28 MECHANICAL THEORY OF STORMS. 
 
 THE GOLDEN MEAN. 
 
 The history of science proves how few have practically re- 
 spected the adage of the ancients, which we have chosen for our 
 motto ; words which ought to be written in letters of gold in 
 every language under the sun. Descartes, by considering the 
 mechanical impulse of the ether sufficient to explain the planet- 
 ary motions, failed to detect the force of gravity in the heavens. 
 Newton, on the other hand, feeling that his law was sufficient 
 to explain them, and requiring a vacuum for its mathematical 
 accuracy, rejected the notion of an ethereal medium. His suc- 
 cessors, following too closely in his footsteps, and forgetting the 
 golden law, have forced themselves into a position by no means 
 enviable. The short-period comet has driven them to a resisting 
 medium, which, while according to Encke's hypothesis of in- 
 creasing density around the sun, it explains the anomalies of 
 one periodical comet, requires a different law of density for 
 another, and a negative resistance for a third. 
 
 OUTLINES OF THE PROBLEM. 
 
 From the position we now occupy, we can see the outlines of 
 the problem before us, viz. : To reconcile the existence of an 
 ethereal medium with the law of gravitation, and to show the 
 harmony between them. We shall thus occupy the middle 
 ground, and endeavor to be just to the genius of Descartes, 
 without detracting from the glory of Newton, by demonstrating 
 the reality of the Cartesian vortices, and by showing that the 
 ether is not affected by gravitation, but on the other hand is 
 least dense in the centre of our system. But what (it may be 
 asked) has this to do with the theory of storms ? Much every 
 way. And we may so far anticipate our subject as to assert 
 that every phenomenon in meteorology where force is concerned, 
 is dependent on the motions of the great sea of electric fluid 
 
MECHANICAL THEORY OF STORMS. 29. 
 
 which surrounds us, in connection with its great specific, caloric. 
 If we are chargeable with overweening pretensions, let it be 
 attributed to the fact that for the last fifteen years we have 
 treated the weather as an astronomical phenomenon, calculated 
 by simple formulae, and that the evidence of its truth has been 
 almost daily presented to us, so as to render it by this time one 
 of the most familiar and palpable of all the great fundamental 
 laws of nature. True, we have neither had means nor leisure 
 to render the theory as perfect as we might have done, the 
 reason of which we have already communicated. 
 
 MOTIONS OF THE STARS. 
 
 In investigating the question now before us, we shall first 
 take the case of an ethereal vortex without any reference to the 
 ponderable bodies which it contains, considering the ether to 
 possess only inertia. If there be a vortex around the sun, it is 
 of finite extent ; for if the ether be co-extensive with space, and 
 the stars likewise suns with surrounding vortices, the solar vor- 
 tex cannot be infinite. That there is an activity in the heavens 
 which the mere law of attraction is incompetent to account for, 
 is an admitted fact. The proper motions of the fixed stars have 
 occupied the attention of the greatest names in astronomy, and 
 motions have been detected, which according to the theory of 
 gravity, requires the admission of invisible masses of matter in 
 their neighborhood, compared with which the stars themselves 
 are insignificant. But this is not the only difficulty. No law 
 of arrangement in the stars can exist that will save the Stellar 
 system from ultimate destruction. The case assumed by Sir 
 John Herschel, of a cluster, wherein the periods shall be equal, 
 cannot be made to fulfil the conditions of being very numerous, 
 without infringing the other condition the non-intersection of 
 their orbits ; while the outside stars would have to obey another 
 law of gravitation, and consequently would be still more liable 
 
-30 MECHANICAL THEORY OF STORMS. 
 
 to derangement from their ever-changing distances from each 
 other, and from those next outside; in brief, the stability of 
 those stars composing the cluster would necessarily depend on 
 the existence of outside stars, and plenty of them. But these 
 outside stars would follow the common law of gravity, and must 
 ultimately bring ruin on the whole. We know such clusters do 
 exist in the heavens, and that the law of gravity alone must 
 bring destruction upon them. This is a case wherein modern 
 science has been instrumental in drawing a veil over the fail- 
 proportions of nature. That such collections of stars are not 
 designed thus to derange the order of nature, proves a priori, 
 that some other conservative principle must exist; that the me- 
 dium of space must contain many vortices eddies, as it were, 
 in the great ethereal ocean, whose currents are sweeping along 
 the whole body of stars. We shall consider, (as a faint shad- 
 owing of the glorious empire of Omnipotence,) that the whole 
 infinite extent of space is full of motion and power to its farthest 
 verge ; and it may be an allowable stretch of the imagination 
 to conceive that the whole comprises one infinite cylindrical 
 vortex, whose axis is the only thing in the universe in a state of 
 absolute unchangeableness. 
 
 VORTICOSE MOTION. 
 
 Let us for a moment admit the idea of an infinite ocean of 
 fluid matter, having inertia without gravity, and rotating around 
 an infinite axis. In this case there is nothing to counteract the 
 effect of the centrifugal force. The elasticity of the medium 
 would only oppose resistance in a vortex of finite diameter. 
 Where it is infinite, each cylindrical layer is urged outward by 
 its own motion, and impelled also by those behind. The result 
 would be that all the fluid would at last have left the axis, 
 around which would exist an absolute and eternal void ; into 
 which neither sound, nor light, nor aught material, could enter. 
 
 
MECHANICAL THEORY OF STORMS. 31 
 
 The case of a finite vortex is very different. However great the 
 velocity of rotation, and the tendency of the central parts to re- 
 cede from the axis, there would be an inward current down 
 either pole, and meeting at the equatorial plane to be thence 
 deflected in radii. But this radiation would be general from 
 every part of the axis, and would be kept up as long as the 
 rotation continued. If the polar currents can supply the drain 
 of the radial stream, that is, if the axis of the vortex is not too 
 long for the velocity of rotation and the elasticity of the ether, 
 there will be no derangement of the density, only a tendency. 
 And in this case the periodic times of the parts of the vortex 
 will be directly as the distances from the axis, and the absolute 
 velocities will be equal. 
 
 FORMATION OF VORTICES. 
 
 There is reason to suspect that Newton looked at this ques- 
 tion with a jaundiced eye. To do it justice, we must consider 
 the planetary matter in a vortex, as the exponent of its motion, 
 and not as originating or directing it. If planetary matter be- 
 comes involved in any vortex, it introduces the law of gravita- 
 tion, which counteracts the expulsive force of the radial stream, 
 and is thus enabled to retain its position in the centre. A pre- 
 dominating mass in the centre will, by its influence, retain other 
 masses of matter at a distance from the centre, even when ex- 
 posed to the full power of the radial stream. If the power of 
 the central mass is harmoniously adjusted to the rotation of the 
 vortex, (and the co-existence of the phenomena is itself the 
 proof that such an adjustment does obtain,) the two principles 
 will not clash or interfere with each other. Or in other words, 
 that whatever might have been the initial condition of the solar 
 vortex, the ultimate condition was necessarily one of equilibrium, 
 or the system of the planets would not now exist. With this 
 view of its constitution, we must consider that the periodic times 
 
82 MECHANICAL THEORY OF STORMS. 
 
 of the planets approximately correspond to the times of the con- 
 tiguous parts of the vortex. Consequently, in the solar vortex, 
 the density of the ether is directly as the square roots of the 
 distances from the axis. This is not the place fully to enter 
 into a discussion of the question, or to show that the position 
 of each planet in the system is due to the outstanding, uncom- 
 pensated, portion of the expulsive force of the radial stream, 
 modified by the density of the ether within the planets, and also 
 by their own densities, diameters, inclinations of axis, and 
 periods of rotation. That Jupiter could not remain in the orbit 
 of Mercury, nor Mercury in that of Jupiter, by merely exchang- 
 ing periods and distances, but that each planet can only be in 
 eqnilibrio in its own orbit. That any change in the eccentrici- 
 ties of the planetary orbits will neither increase nor diminish the 
 action of the radial stream of the vortex, and consequently will 
 not interfere with the law of gravitation. In relation to the 
 numerous questions that will spring up from such a position, it 
 is sufficient here to say, that it is believed all Objections can be 
 satisfactorily answered ; while, by this light, a long range of 
 phenomena that have hitherto baffled the sagacity of the wise, 
 come out plainly, and discover their parentage. 
 
 In cometary astronomy we shall find much to substantiate 
 these views. The anomalies in their motions, the discrepancies 
 in their periods, calculated from different sets of observations, 
 their nebulosities and appendages, will all receive a satisfactory 
 solution ; and these lawless wanderers of the deep be placed in 
 a more interesting light. 
 
 TEST OF A THEORY. 
 
 It has been remarked that the best evidence of the truth of 
 a theory, is its ability to refer to some general principle, the 
 greatest number of relevant phenomena, that, like the com- 
 ponent masses of the chiselled arch, they may mutually bind 
 
MECHANICAL THEORY OF STORMS. 33 
 
 and strengthen each other. This we claim to be the character- 
 istic of this theory. At the outset -it. was not intended to allude 
 to more than was actually necessary to give an outline of the 
 theory, and to introduce the main question, yet untouched. 
 We have exhibited the stones of which the arch is composed ; 
 but they may be pasteboard, for the reader has not handled 
 them. We will now produce the keystone, and put it in its 
 place. This he shall handle and weigh. He will find it hard, 
 a block of granite, cut from the quarry of observed facts, and 
 far too heavy to be held in its place by a mere pasteboard 
 structure. 
 
 ENUNCIATION OF THE THEORY. 
 
 Quitting, therefore, the region of the planets, we will come 
 down to the surface of our own globe, to seek for some more 
 palpable evidence of the truth of the following propositions : 
 
 1st. That space is filled with an elastic fluid, possessing 
 inertia without weight. 
 
 2d. That the parts of this fluid in the solar system circulate, 
 after the manner of a vortex, with a direct motion. 
 
 3d. That there are also secondary vortices, in which the 
 planets are placed. 
 
 4th. That the earth is also placed in a vortex of the ethereal 
 medium. 
 
 5th. That the satellites are passively carried around their 
 primaries, with the ethereal current, and have no rotation rela- 
 tive to the ether, and therefore they always present the same 
 face to their primaries, and have no vortex. 
 
 The consideration of these propositions involves many others, 
 many difficulties, many apparent anomalies and contradictions, 
 which should bespeak for such a theory, the offspring of ob- 
 servation, without the aid afforded by the knowledge of others, 
 and of toil without leisure, a large share of indulgence. With 
 this we will close these preliminary remarks, and present our 
 
 2* 
 
84 MECHANICAL THEOEY OF STORMS. 
 
 theory of the physical cause which disturbs the equilibrium of 
 our atmosphere, and which appears the principal agent in the 
 production of storms, in the following words : 
 
 The dynamical axis of the terral vortex passes through the 
 centre of gravity of the earth and moon, and is continually cir- 
 culating over the earth's surface in both hemispheres, in a 
 spiral, its latitude and longitude, at any particular time, being 
 dependent, 
 
 1st. On the relative mass of the moon. 
 
 2d. On the inclination of the axis of the vortex to the earth'e 
 axis. 
 
 3d. On the longitude of the ascending node of the vortex on 
 the lunar orbit. 
 
 4th. On the longitude of the ascending node of the lunar 
 orbit on the ecliptic. 
 
 5th. On the eccentricity of the lunar orbit at the time. 
 
 6th. On the longitude of the perigee of the lunar orbit at the 
 time. 
 
 7th. On the moon's true anomaly at the time. 
 
 MASS OF THE MOON". 
 
 Those elements which represent the moon's distance and 
 motion are accurately known, and may be taken from the 
 Nautical Almanac, being all embodied in the moon's parrallax 
 or semi-diameter, and in the declination and right ascension ; 
 but for the most important element, the moon's mass, we in vain 
 look to astronomy. In fact, it may be averred that the import- 
 ance attached to astronomical authority, concerning the mass of 
 the moon, has caused more trouble than any other question of the 
 whole theory, until we trusted implicitly to the theory itself to de- 
 termine it. The determination of three unknown elements, viz. : 
 the moon's mass, the inclination of the axis of the vortex, and the 
 right ascension of that axis, is a more difficult problem than at 
 
MECHANICAL THEORY OF STORMS. 35 
 
 first sight appears, owing to the nature of the phenomena, which 
 affords the only clue for its solution. There are six principal 
 vortices ever hi operation on the surface of tne eartli, and tluir 
 disturbing influence extends from 200 to 400 miles. To find 
 the precise centre, by one observer confined to one plaee, is 
 difficult ; and to separate them, so as to be fully assured tint 
 you have the right one, is perhaps still more so. Happily this 
 tedious labor is accomplished, and we are able with confidence 
 to give the following important elements, as very close approxi- 
 mations to the truth : 
 
 Mass of the moon .......... 
 
 Obliquity of the axis of "the vortex . 15 1 to 32 variable. 
 Right ascension of ditto ..... 250 to 290 variable. 
 
 It must be borne in mind that we are now discussing the 
 main or central vortex of the earth; but before applying them 
 to the calculation, we will explain the modus operand i, waving 
 for the present the consideration of the law of density in (lie 
 Terral vortex. It is evident at first sight that if the periodic 
 times of the parts of the vortex contiguous to the moon, are 
 equal to the moon's period approximately, that the velocity of 
 the ether is greater at the surface of the earth than the velocity 
 of that surface. Now, we have before argued that the ether 
 possesses inertia, it therefore would under such circumstances 
 exert some mechanical action. Consequently, the aerial en- 
 velope of our globe, or its superior stratum, is impelled east- 
 ward by convection* of the more rapidly rotating ether. And 
 from the extreme tenuity of its upper layers, is probably forced 
 into immense waves, which will observe to a certain degree, a 
 general paralellism north and south. 
 
 * A term adopted by Prof. Faraday t<> denote the mode iu whVh 
 bodies are carried along by an electrical current. 
 
36 MECHANICAL THEORY OF STORMS. 
 
 ATMOSPHERIC CURRENTS. 
 
 It is a well-known fact, that the prevailing current of the at- 
 mosphere in high latitudes is from the westward. The cause 
 of this is ascribed by Professor Dove to the transfer of the equa- 
 torial portions to a higher latitude, by which the excess of its 
 rotative velocity is made apparent, by outstripping the slower 
 moving surface in its progress eastward. No doubt some effect 
 is due to this, but still a difficulty remains. Let us follow this 
 current. The polar current reaches the surface on the borders 
 of the trades with less rotative velocity than the surface, and is, 
 therefore, met by the surface as a current partaking of both mo- 
 tions. In the northern hemisphere it is north-east deflected to 
 east as it approaches the southern trades. By the same rea- 
 soning, coming from the north before it reaches the surface, it 
 ought to be also a north-east wind above the lower westerly 
 currents. Now it is an observed fact, that while in the latitude 
 of New York, for instance, the lower westerly winds are to the 
 easterly, as 3 or 4 to 1, in the highest regions of observed 
 clouds, the ratio is much increased ; and according to our own 
 observations in this place,* we have never seen the highest 
 cirrus clouds moving westward. How then is this continual in- 
 terchange kept up ? Assuredly we cannot have a current from 
 the poles without a contrary current to the poles. If we go 
 into the arctic circle, we again find the westerly and northerly 
 winds predominating. If the current from the equator follows 
 the surface, the westerly winds ought to be south-west. If it 
 be above the surface wind, then the surface wind is the polar 
 current, and ought to be north-east. Whereas, from the testi- 
 mony of all who have visited these regions, the prevailing winds 
 are north-west. How can this be ? 
 
 Again, it is proved that the upper current near the equator 
 is also from the westward as near due west as possible. Take 
 * Ottawa, HI. 
 
MECHANICAL THEORY OF STOKMS. 87 
 
 the latitude of St Vincent. The difference between the cosein 
 of 13 and radius applied to the circumference, is about 600 
 miles, which would give 25 miles per hour to the eastward, in 
 lat. 13. But to do this, it is necessary to transfer it suddenly 
 from the equator ; for by a slow motion the easterly tendency 
 would be lost. Give it 24 hours from the equator to lat. 13, 
 without any loss of easterly tendency, and it comes to that 
 latitude with a velocity of 38 miles per hour to the northward, 
 and only 25 to the eastward ; we have, therefore, a wind from 
 south-west by south. Yet it is known that in the tropics the 
 highest visible clouds move from the westward. But as no such 
 case could occur as a transfer in twenty-four hours without loss, 
 and if we diminish the time, the wind is still more southerly. 
 Meteorologists usually cite the falling of ashes at Jamaica during 
 the eruption of Coseguina, in Guatamala, in February 1835, as 
 coming from south-west, whereas the true direction was about 
 west south-west, and the trade wind below was about north. 
 But do we deny that there is an interchange between the frigid 
 and torrid zones ? By no means ; but we would show that the 
 great controlling power is external to our atmosphere, and that 
 the relative velocities of the earth and the atmosphere is not 
 alone adequate to account for it. By this view the polar cur- 
 rent is a north-west wind (which is impossible by Professor 
 Dove's theory), or is carried eastward by electric convection. 
 
 BUTTON'S THEORY, 
 
 Whether we adopt the views of Fourier or Poullet, as to the 
 temperature of the planetary spaces, it is certain that it is at 
 least equal to, or less than, the lowest temperature of our globe. 
 It is also a well-known fact, that the capacity of air to hold 
 vapor in solution, increases in a higher ratio than the tempera- 
 ture, so that the intermingling of saturated portions of air, at 
 different temperatures, must necessarily be attended by precipi- 
 
38 MECHANICAL THEORY OF STOEMS. 
 
 tation of moisture. This idea was advanced by Doctor Hutton, 
 and considered competent to account for the prominent meteor- 
 ological phenomena, until Professor Espy broached a question- 
 able principle, (and which is rendered still more so by the 
 late investigations of Regnault,) in opposition to Button's theory. 
 That the theory is deficient, no one can gainsay. That Espy 
 has rendered the question clearer, is equally hazardous to assert. 
 Hutton failed in showing a cause for such intermingling on a 
 sufficient scale ; while Espy, it may be suspected, has misinter- 
 preted facts, and incautiously rejected the only element possess- 
 ing the power of raising the storm. 
 
 GREAT SPECIFIC HEAT OF THE ETHER. 
 
 Whatever may be the degree of condensation or rarefaction 
 in the terral vortex, there must necessarily be a current down 
 the pole or axis,' thence to be deflected along the equatorial 
 plane of the vortex, and this drain will be as perpetual as the 
 rarefaction of the centre, (caused by the centrifugal force of rota- 
 tion,) which calls it forth. It will now be perceived that the 
 fluid of the vortex, which we shall still term ether, is neither 
 more nor less than the electric fluid, the mighty energising 
 principle of space, the source of motion, the cause of mag- 
 netism, galvanism, light, heat, gravity, of the aurora, the light- 
 ning, the zodiacal light, of the tails and nebulosities of comets, 
 of the great currents of our atmosphere, of the samiel, the hur- 
 ricane, and the earthquake. It will be perceived that we treat 
 it as any other fluid, in relation to its law of motion and con- 
 densation. But we have no right to base our calculations on 
 its resistance, by the analogies presented by ponderable or 
 atomic matter. Atomic fluids, even pure air, may be con- 
 sidered viscid and tenacious when compared to an infinitely 
 divisible fluid, between whose particles (if we may use the term) 
 no attraction of any kind exists. No ponderable matter can 
 
MECHANICAL THEORY OF STORMS. 89 
 
 come in close contact without feeling the influence of the gravi- 
 tating force which, at insensible distances, such as the breadth 
 of a wave of ether, is increased in power, and becomes a co- 
 hering and combining force. We contend that thjrffuid is the 
 only fluid of space ; when condensed it is positive, and seeks to 
 escape ; when rarefied it is negative, and receives from the con- 
 tiguous space a restoration of its power. That it can give and 
 receive, from planetary matter, what we call motion ; and con- 
 sequently can affect the temperature of such matter, and be in 
 turn affected by it. And finally that, for its degree of inertia, 
 it exceeds in elasticity and specific heat all other matter. 
 
 PROCESS OF DERANGEMENT. 
 
 This premised, we see that as the axis of the vortex traverses 
 the surface of the earth, there is a tendency to derange the elec- 
 tric state of the parts travelled over, by bringing the atmosphere 
 and surface of the earth under the rarefied centre of the vortex. 
 For it is not the ether of the atmosphere alone that is affected. 
 It is called forth from the earth itself, and partakes of the tem- 
 perature of the crust, carrying up into the upper regions the 
 vapor-loaded atmosphere of the surface. The weather now feels 
 close and warm ; even in winter there is a balmy change in the 
 feelings. The atmosphere then fills with haze, even to the 
 highest regions of the clouds ; the clouds themselves are ill 
 defined ; generally the wind comes in at E. S-E., or S., getting 
 very fresh by the time it chops round to W. In from six to 
 twelve hours from the time of the meridian passage, in this lati- 
 tude, the Big Cumuli have formed, and commenced their 
 march eastward. In summer time there is always thunder 
 and lightning, when the passage is attended or followed by a 
 storm. In winter, generally, but not always. In summer, the 
 diameter of the storm is contracted ; in winter, dilated ; in con- 
 sequence of this, summer is the best season to trace the vortices 
 
40 MECHANICAL THEORY OF STORMS. 
 
 of the earth through their revolutions. Let us now attend a 
 little to the results. The ether of. the surface atmosphere par- 
 takes of the temperature of that atmosphere, so also the ether 
 of the earth's crust partakes of the temperature of the crust ; 
 and its escape is rapid, compared with the ascent of the air. 
 When it arrives at the colder layers of air above, its temperature 
 sinks, and, on account of the greater specific caloric, it imparts 
 a much higher temperature to those layers than is due to their 
 position ; an elevation consequently takes places, begetting a 
 drain from below, until the upper regions are loaded with a 
 warm and vapory atmosphere. If the action of the sun con- 
 spires at the same time to increase the effect, the storm will be 
 more violent. In twelve hours after the meridian passage of 
 the vortex, the storm is brought under the parts of the ethereal 
 atmosphere of the earth most remote from the axis ; a reaction 
 now takes place ; the cold ether of space rushes in, and, on ac- 
 count of its great specific caloric, it abstracts from the warm 
 atmosphere more than pertains to the difference of temperature, 
 and there is a great condensation. Rain and hail may form in 
 fearful quantities; and when the equilibrium is restored, the 
 temperature will have fallen many degrees. 
 
 As it is important that we should have a clear view of the 
 character of the ether, we will revert to the principle we have 
 advocated, viz. : that in equal spaces there are equal momenta. 
 What the ether wants in inertia, is made up by its motion or 
 specific heat, considering in this case inertia to stand for weight 
 when compared with ponderable matter ; so that to raise an 
 equivalent amount of inertia of ether to the same temperature 
 as atmospheric air, will require as much more motion or spe- 
 cific heat as its matter is less. And this we conceive to be a 
 law of space in relation to all free or gaseous matter. To apply 
 it to solids would require a knowledge of the amount of force 
 constituting the cohesion of the solid. 
 
MECHANICAL THEORY OF STORMS. 41 
 
 INFLUENCE OF DIMINISHED PRESSURE. 
 
 But there is another principle which modifies these effects. 
 We have already adverted to the action of the tangential cur- 
 rent of the vortex forcing the outer layers of the atmosphere 
 into waves. These waves will be interfered with by the differ- 
 ent vortices, sometimes being increased and sometimes dimin- 
 ished by them.* If these waves are supposed very wide, (which 
 would be the case in the attenuated outside layers of the atmos- 
 phere,) the action of the vortex will be greater in its passage 
 over a place, which at the time corresponded to the depression 
 point of the wave, that is, to the line of low barometer ; because 
 here there would be less resistance to overcome in the passage 
 of the ether from the surface of the earth into space ; so that 
 we may conceive each vortex making a line of storms each day 
 around the earth, separated by less disturbed intervals. After 
 the formation of the storm, it of course has nothing to do with 
 the vortex that produced it ; it travels in the general direction 
 of the local atmosphere. of the place in intratropical latitudes 
 westward, in extratropical latitudes eastward. If, therefore, the 
 disturbance forms at the place of observation, there will prob- 
 ably be no storm ; but further eastward its action would be 
 more apparent or violent. It is impossible, of course, to lay 
 down any general description which shall meet every case. It 
 is a knowledge that can only be acquired by observation, and 
 then is not readily or easily communicated. There are many 
 contingencies to be allowed for. and many modifying causes to 
 keep sight of, to enter into which would only be tedious ; we 
 shall, therefore, confine ourselves to the prominent phenomena. 
 
 * The principal cause of these waves is, no doubt, due to the vortices, 
 and the eastern progress of the waves due to the rotating ether ; but, at 
 present, it will not be necessary to separate these effects. 
 
MECHANICAL THEORY OF STORMS. 
 
 ACTION OF THE POLAR CURRENT. 
 
 We have seen how the passage of the axis of the vortex may 
 derange the electric tension of the parts passed over ; but there 
 is another mode of action not yet adverted to. 
 
 Jig! 
 
 When the moon is at her perigee, the axis of the vortex 
 passes through the centre of gravity of the earth and moon at 
 C, and cuts off the segment R R. At the apogee, on account of her 
 greater distance, and of her consequent power to push the earth 
 out from the axis of the vortex X X, the segment R' R' is only 
 cut off by the axis ; and the angle which the axis makes with 
 the surface will vary with the arcs A R and A' R' ; for these arcs 
 will measure the inclination from the nature of the circle. In 
 passing from the perigee to the apogee the axis will pass over 
 the latitudes intermediate between R and R' in both hemispheres, 
 neither reaching to the equator E, nor to the pole P. Let us 
 now suppose a meridian of the earth, represented by the line 
 N R S, N being north, and S south, and the surface of the at- 
 mosphere by N' S' ; XX still representing the axis of the vortex, 
 ordinarily inclined 34 or 35 to the surface. Let us also con- 
 ceive the rotation of the earth to cease, (the action of the vortex 
 remaining the same,) thus leaving the axis over a particular 
 longitude. If the ether possesses inertia, there will be an actual 
 
MECHANICAL THEORY OF STORMS. 
 
 43 
 
 Fin. 
 
 scooping out of the upper portions, driving them southward to 
 a certain distance, where the atmosphere will be piled up above 
 the ordinary level. There will, therefore, be a strong contrary 
 current at the surface of the earth to restore the equilibrium, 
 and if the action be violent, the surface wind will be increased; 
 so that if it be considered tangential to the surface at S, its own 
 momentum will tend to make it leave the surface and mount up 
 to T ; and in this way increase the action due to the ether. 
 Now, although the axis is never stationary, but travels round 
 the earth in less than twenty-five hours, yet there is a tendency 
 to this mode of action ; and it is even sometimes palpable to the 
 observer when the axis has passed immediately to the north- 
 ward ; for the pinnate shafts and branching plumes of the cirri 
 often reach far to the south of the southern boundary of the 
 storm. These shafts are always longer when radiating from the 
 northward than when proceeding from the southward. The 
 cause is understood by the above figure. At such a time, after 
 dark, the auroral shafts will also be seen over the storm to the 
 northward, but will be invisible to those beneath. There is this 
 to be observed, however, that the visibility of the ethereal cnr- 
 
44 MECHANICAL THEORY OF STORMS. 
 
 rent (or the aurora) is more frequent when the passage of the 
 vortex is not attended with any great commotion, its free pass-age 
 being perhaps obstructed by too dry an atmosphere ; hence it 
 becomes more visible. But it may be asserted that a great 
 aurora is never seen except when a vortex is near, and to the 
 northward, and within a few hours of its passage over the me- 
 ridian. We have, however, seen partial auroras to the south 
 when none existed north, and also cases when the radiation was 
 from west, but they are never as bright as in the north. They 
 are all due, however, to the same cause ; and we have frequently 
 followed a vortex for three days to the northward, (that is, seen 
 the effects of its meridian passage,) at 700 miles distance, by 
 the aurora, and even by the lightning, which proves plainly that 
 the exterior layers of our atmosphere can reflect a flash of 
 lightning, assisted by the horizontal refraction, otherwise the 
 curvature of the earth would sink it ten miles below the 
 horizon. 
 
 LIMITS OF THE VORTEX. 
 
 The action of the polar current of the ether, therefore, tends 
 to cause a depression of the barometer, and an elevation to 
 the northward and southward, and there is a general set of the 
 wind below to the point of greatest depression. The action of 
 the tangential current works the outer surface of the atmosphere 
 into great ridges and hollows, whose distances apart as well as 
 actual dimensions, are continually changing under the influ- 
 ences of causes not yet alluded to, and it is in the hollows where 
 the action of the polar current will be principally expended. 
 Luckily for the earth, the axis of the vortex is never long in 
 passing over any particular place. In this latitude, whose nat- 
 ural cosine is three-fourths, the velocity westward is over 700 
 miles per hour ; but at its extreme limits north, the motion is 
 much slower, and is repeated for two or three days in nearly 
 the same latitude, for then it begins to return to the south ; thus 
 
MECHANICAL THEORY OF STORMS. 45 
 
 oscillating in about one sidereal period of the moon. At its 
 southern limit, the vortex varies but slowly in latitude for the 
 same time, but the velocity is much greater. The extreme lat- 
 itudes vary at different times with the eccentricity of the lunar 
 orbit, with the place or longitude of the perigree, and with the 
 longitude of the moon's ascending node, but in no case can the 
 central vortex reach within 5 of the equator, or higher than 
 about 75 of latitude north or south. Heojce there are no 
 storms strictly speaking beyond 83* of latitude ; although a 
 storm may be raging close by, at the turning point south, and 
 draw in a very strong gale from the northw&rd with a clear sky 
 above. So also, although rains and short squalls may be fre- 
 quent in the vapor-loaded atmosphere of the equator, yet the 
 hurricane does not reach there, owing to the adjustment of the 
 mass and distance of the moon, and the inclination of the axes 
 of the vortices to the axis of the earth. If the temperature of 
 the upper limit or highest latitude of the vortex, was equal to 
 the temperature which obtains at its lowest limit, and the daily 
 extremes of the solar influence as great, the hurricanes would be 
 as violent at the one as the other, and even more so on account 
 of the smaller velocity. But the deficiency of temperature and 
 moisture, (which last is all-important,) prevents the full develop- 
 ment of the effect. And even in the tropics, the progress of the 
 sun, by its power in directing the great annual currents of the 
 atmosphere, only conspires in the summer and autumn months, 
 to bring an atmosphere in the track of the vortices, possessing 
 the full degree of moisture and deficiency of electric tension, to 
 produce the derangement necessary to call forth the hurricane 
 in its greatest activity. 
 
 * The inner vortex may reach as high as 83 when the moon's orbit 
 is favorably situated. 
 
46 MECHANICAL THEORY OF STORMS. 
 
 ROUTINE OF A STORM. 
 
 The novelty and originality of this theory will perhaps justify 
 us in dwelling a little longer on what observation has detected. 
 The vortex (and we are now speaking only of the central vor- 
 tex) does not derange every place alike, but skips over large 
 tracts of longitude in its progress westward. We speak here 
 of the immovable axis of the vortex as in motion ; in reality it 
 is the rotation of the earth which brings every meridian under 
 its influence in some latitude once every twenty-four hours. The 
 centre of greatest derangement forms the nucleus, towards which 
 the surface currents, under certain restrictions, flow. The strong- 
 est current will, however, usually be from the south, on account 
 of the inclination of the axis of the vortex to the surface of the 
 earth.* These currents continuing onwards by their vires in- 
 ertias, according to the first law of motion, assist somewhat in 
 conveying the warm surface wind, loaded with moisture, into 
 the region of cloud ; and the diminution of temperature causes 
 the condensation of large masses of vapor, according to Button's 
 views ; and the partial vacuum thus produced, causes a still 
 greater intermingling. But we have already shown that this is 
 not the sole cause, nor is it ever more than partially accom- 
 plished. The ether of the lower atmosphere, and of the crust 
 of the earth, is disturbed, and rushes towards the rarefied axis 
 from the surface, and with the temperature of the surface, thus 
 conveying the surface atmosphere, in a measure, along with it. 
 In the upper regions, this ether (or electric fluid) cools down, 
 or parts with some of its heat, to the air of those regions, and, 
 by its great specific caloric, necessarily and unduly increases the 
 temperature of the air. This, by its expansion and ascension, 
 will cause a further influx from below, until the upper atmos- 
 phere becomes loaded with vapor. In twelve hours, at least, a 
 
 * The curvature of the earth is more than 10 miles in a distance of 
 300 miles. 
 
MECHANICAL THEORY OF STORMS. 47 
 
 reaction must take place, as that part of the earth's surface is 
 carried six or seven thousand miles from the axis, where the 
 ether is more dense. This in turn descends to the surface, 
 carrying with it the temperature of space, at least 60 below 
 zero ; a great condensation must follow ; local derangements of 
 the electric equilibrium in the centre of large clouds, when the 
 condensation is active, must now take place, while partially non- 
 conducting masses intervene, to prevent an instantaneous restora- 
 tion of the equilibrium, until the derangement is sufficient to 
 cause the necessary tension, when all obstacles are rent asunder, 
 and the ether issues forth, clothed in the power and sublimity 
 of the lightning. It is a fearfully-energetic fluid, and, when 
 sufficiently disturbed, competent to produce the most violent 
 tornado, or the most destructive earthquake. That these two 
 phenomena have simultaneously occurred, seems well authen- 
 ticated ; but the earthquake, of course, must be referred gen- 
 erally to derangements of the electric equilibrium of the earth's 
 interior, of which at present we know but little. 
 
 The day or morning previous to the passage of the vortex, is 
 frequently very fine, calm, mild, and sleepy weather, com- 
 monly called a weather breeder. After the storm has fully 
 matured, there is an approach of the clouds to the surface, a re- 
 duction of the temperature above, and the human body feels 
 the change far more than is due to the fall of temperature. 
 This is owing to the cold ether requiring so much heat to raise 
 its temperature to that of surrounding bodies, or, in other words, 
 is due to its great specific caloric. In summer, this falling of 
 the upper layers in front of the storm is so apparent, that every 
 part is seen to expand under the eye by perspective, swelling, 
 and curling, and writhing, like the surface of water or oil when 
 just commenced boiling. The wind now partakes of the 
 motion of the external ether, and moves with the storm east- 
 ward (in this latitude), or from N-E. to S-E., until the action 
 ceases. 
 
48 MECHANICAL THEORY OF STORMS. 
 
 CONDITIONS NECESSARY TO PRODUCE A STORM. 
 
 The vortex, in its passage round the earth, may only meet 
 with a few localities favorable for producing a very violent 
 storm ; but these nuclei will generally be connected by bands 
 of cloudy atmosphere ; so that could we view them from the moon, 
 the earth would be belted like the planet Jupiter. There is 
 reason to suspect, also, that there are variations in the energy 
 of the ethereal motions, independent of the conditions of the 
 earth and its atmosphere, which affects even the radial stream 
 of the sun. For the zodiacal light, which is caused by this 
 radial stream, is at times much more vivid than at others. Also 
 in the case of the aurora, on our own globe. On this point 
 there is much to say, but here is not the place. The conditions 
 favorable for the production of a storm at the central passage 
 of a vortex, are a previous exemption from excitement ceteris 
 paribus, a high temperature and dew point, a depression of the 
 barometer, and local accumulation of electric tension, positive or 
 negative ; and these are influenced by the storms in other places 
 controlling the aerial currents, and thus determining the atmos- 
 phere of the place. 
 
 LATERAL VORTICES. 
 
 We have already alluded to the lateral vortices of the terral 
 system. We must now resort to a diagram. 
 
 In the following figure, the arrows represent the ethereal current 
 of the terral vortex ; the linear circle, the earth ; C the centre 
 of gravity of the earth and moon, and, consequently, the central 
 vortex or axis of the vortex of the earth. / represents the posi- 
 tion of the inner vortex, and that of the outer vortex. 
 These two last are eddies, caused by the obstacle presented by 
 the earth in being pushed out from the centre by the moon, and 
 are called lateral vortices. There are, therefore, two lateral vor- 
 
MECHANICAL THEORY OP STORMS. 
 
 Fiq.3 
 
 l> 
 
 tices, and one central, in both hemispheres, and by this simple 
 arrangement is the earth watered, and the atmospheric circula- 
 tion produced. 
 
 ILLUSTRATION OF THEIR ACTION. 
 
 If we place a globe in a vessel of water, so that the vertex 
 shall only just be covered, and place the globe eccentrically in 
 the vessel, so that the centre of the vessel may not be too far 
 from the outside of the globe, and then impart an equable but 
 slow motion to the water, in the manner of a vortex ; by view- 
 ing the reflected light of the sky from the surface of the water 
 above the globe, we shall be able to trace a succession of 
 dimples, originating at I and 0, and passing off with the cur- 
 rent, and dying away. The direction of the fluid in these little 
 eddies, will be the same as the direction of the current in the 
 main vortex. If we displace the globe, so as to remove it far 
 from the centre of the vessel, and impart the same motion, the 
 vortex I will be found at E, and the direction of the current 
 
 3 
 
50 MECHANICAL TH*EOKY OF STOEMS. 
 
 will be contrary to the 'direction of the fluid in the vessel. In 
 the case of the earth and moon, the displacement can never 
 change the position of the inner vortex much. It will always 
 be to the right hand of the central vortex in north latitudes, 
 and in consequence of the ether striking our globe in such 
 a position, the current that is deflected from its true path, by 
 the protuberance of the earth forcing it inside, is prevented by 
 the circular current of the parts nearer the axis of the vortex, 
 from passing off" ; so that a vortex is formed, and is more vio- 
 lent, ceteris paribus, than the vortex at O. 
 
 ORDER OF OCCURRENCE. 
 
 Whether this mode of action has been correctly inferred, 
 matters little ; the lateral vortices follow the law of such a posi- 
 tion. The inner vortex always precedes the central from five to 
 eight days, when ascending in this latitude, and comes to the 
 meridian after the moon. The outer vortex, on the contrary, 
 follows the central in its monthly round, and comes to the 
 meridian before the moon. It will be readily understood that 
 if the axes of these lateral vortices be produced through the 
 earth, they will pass through similar vortices in the opposite 
 hemisphere ; but as the greatest latitude of the one, corre- 
 sponds to the least latitude of the other, the same calculation 
 will not answer for both. The same remark applies to the 
 central vortex also. 
 
 Thus there are six passages each month over latitude 41 ; but 
 as there are intervals of 3 to 6 between two consecutive pass- 
 ages of the same vortex, it may happen that an observer in the 
 middle latitude, would perhaps see nothing of their effects with- 
 out looking for them. Generally speaking, they are not only 
 seen, but felt. The time of the passage of the outer vortex 
 ascending, corresponds so nearly (in 38 of latitude) at certain 
 times, with the passage of the central vortex descending, that 
 
MECHANICAL THEOEY OF STOEMS. 51 
 
 the two may be considered one if attention is not directed to it. 
 The orbits of these lateral vortices depend, like that of the cen- 
 tral vortex, on the orbit of the moon for eccentricity, but the 
 longitudes of the perigee will not correspond with the longitude 
 of the moon's perigee. This follows from the theory. As the 
 elements of these orbits are only approximately determined, we 
 shall confine our calculations to the orbit of the central vortex. 
 
 REDFIELD'S THEORY OF STORMS. 
 
 It will now appear plainly to the reader, that this theory of 
 storms differs in every particular from the rival theories of Red- 
 field and Espy, both as to the cause and the modus agendi. It 
 would appear at first sight, as if the discovery of these vortices 
 would at once remedy the great defect in the theory of Redfield, 
 viz. : that no adequate cause is assigned for the commencement 
 and continuation of the vorticose motion, in the great circular 
 whirlwinds which compose a storm. The facts, however, are ad- 
 verse to such an application. According to Mr. Redfield, the 
 rotation of a circular storm in the northern hemisphere is from 
 right to left, and the reverse in the southern. The author's at- 
 tention has, of course, been considerably directed to this point ; 
 but in every case he has been unfortunate in finding in the clouds 
 a rotation from left to right. Some cases are mentioned in the 
 appended record of the weather. He has also noticed many of 
 those small whirlwinds on arid plains, in Egypt, in Mexico, and 
 in California, which, in the great majority of cases, were also 
 from left to right. His opportunities, however, have not ex- 
 tended to the southern hemisphere. This theory has not, how- 
 ever, been formed on theoretic views, but by looking nature in 
 the face for years, and following her indications. Accordingly, 
 we find that the changes of the wind in a storm forbid the 
 adoption of the circular hypothesis. 
 
52 MECHANICAL THEORY OF STORMS. 
 
 WHIRLWINDS VERY LIMITED IN DIAMETER. 
 
 The theory, as extended by Col. Reid, rests on a simple rota- 
 tion around a progressing centre, and is found sometimes sup- 
 ported by evidence of the most violent action at the centre, and 
 sometimes by showing that the central portion is often in a 
 state of calm. We do not attempt to reconcile these views ; but 
 would merely observe, that an atmospheric vortex must be sub- 
 ject to the same dynamical laws as all other vortices ; and inas- 
 much as the medium cannot differ greatly in density, from the 
 centre to the circumference, the periodic times of the parts of 
 the vortex, must be directly as their distances from the axis, and 
 consequently the absolute velocities must be equal. If Mr. Red- 
 field resorts to a spirally inward current, it would be a centri- 
 petal instead of a centrifugal current, and therefore could not 
 cause the barometer to fall, which was the best feature of the 
 theory in its primitive form. The absolute velocity of the wind 
 is the important element which most concerns us. In the case 
 of a tornado of a few yards in diameter, there is no doubt a 
 circular motion, caused by the meeting of opposing currents ; 
 but this may be considered a circle of a very small diameter. 
 The cause is due to a rapid escape of electric or ethereal matter, 
 from the crust of the earth, called forth by the progressing, dis- 
 turbed space above ; this involves the air, and an ascending 
 column in rotation begets the rush on all sides to that column 
 in straight lines : consequently, the velocities will be inversely as 
 the distances from the axis, and the force of the current as the 
 squares of the velocities. On the circular theory, no increase of 
 velocity would be conferred by the approach of the centre, and 
 consequently no increase of power. 
 
MECHANICAL THEORY OF STORMS. 53 
 
 OBJECTION TO CIRCULAR STORMS. 
 
 Another objection to the circular theory of storms, is the 
 uniformity of phase. - If that theory be true, we see no reason 
 why a person should not be sometimes on the northern side of 
 the gale. By referring to a diagram, we perceive that on the 
 northern side the changes of the wind pursue a contrary direc- 
 tion to what they do on the south, yet in nine cases out of ten, 
 each vessel meeting a hurricane will find the same changes of wind 
 as are due to the southern side of the storm. It is true, that if 
 a vessel be to the northward of a great hurricane, there will 
 almost certainly be a north-east gale drawn in, and this might 
 be set down as the. outer limits of a circular storm. But when 
 the storm really begins, the wind comes round south-east, south, 
 south-west, ending at north-west, and frequently is succeeded, on 
 the following day, (if in middle latitude,) by a moderate breeze 
 from the northward. Now, if the north-east gale spoken of 
 above, was the outer limits of an atmospheric vortex, a vessel sail- 
 ing west ought not to meet the hurricane, as a north-east wind is 
 indicative of being already on the west side, or behind the storm. 
 Again, the characters of the winds, and appearances at the 
 different changes, are opposed to the circular theory. At a dis- 
 tance of fifty miles from the centre of a storm, the wind which 
 passes over a ship as a southerly wind, will have made a rota- 
 tion and a half, with the -hurricane velocity, before the same 
 wind can again pass the ship as a northerly wind, (supposing 
 the progress eastward, and the ship lying to,) that is, the same 
 wind which in another place was a south wind two hours before, 
 and after only going one degree north, becomes a northerly 
 wind, changed in character and temperature, as every seaman 
 is well aware. In a storm, if the circular theory be true, the 
 character and temperature should be the same, no matter from 
 what point the wind is blowing. This should be a conclusive 
 argument. 
 
54 MECHANICAL THEOKY OF STOEMS. 
 
 Mr. Espy has also changed his ground on the storms of the 
 United States ; he does not now contend that the winds blow 
 inwards to a centre, but to a line either directly or obliquely. 
 Thus we see that while Mr. Redfield concedes to Mr. Espy a 
 spirally inward current, the latter also gives up a direct current 
 to the centre, to Mr. Redfield. This shows at least an approxi- 
 mation to the truth. 
 
 It is not necessary for the support of this theory, that we 
 should derive any materials from the ruins of others ; we shall 
 therefore not avail ourselves of certain discrepant results, which 
 can be found in many of the storms cited by Colonel Reid. 
 With respect to Mr. Espy's cause of storms, the experiments of 
 Regnault may be considered as decisive of the question : 1st, 
 because the specific heat of vapor is so much less than Espy 
 assumed it to be ; and 2d, because the expansion of air in a free 
 space does not suffer any change of volume by ascending, ex- 
 cept what is due to diminished pressure, and the natural tem- 
 perature of that elevation. 
 
 INDICATIONS OF A STORM. 
 
 In accordance with our theory, the direction and force of the 
 wind in a storm are due to ascending columns of air, supplied 
 from the upper portion of the atmospheric stratum beneath the 
 clouds. The commotion begins at the highest limits of the 
 cirri, and even at greater elevations. Hence, the hazy appear- 
 ance of the sky is a legitimate precursor of the coming gale. 
 As a general thing, the wind will blow (at the surface) towards 
 the centre of greatest commotion, but it is too dependent on the 
 ever-varying position and power of temporary nuclei of disturb- 
 ance, to be long steady, except when the disturbance is so re- 
 mote that its different centres of induction are, as it were, 
 merged into one common focus. When a vortex is descending, 
 or passing from north to south, and withal very energetic at the 
 
MECHANICAL THEORY OF STOKMS. 55 
 
 time, the southerly wind (which may always be considered the 
 principal wind of the storm in this hemisphere) may blow 
 steadily towards the vortex for three or even four days. When 
 a vortex is ascending, the induced northerly current will be 
 comparatively moderate, and be frequently checked by the 
 southerly wind overblowing the storm, and arriving the day 
 before the vortex which produced it. 
 
 The important point for the navigator, is to know the time 
 of meridian passage of the vortex, and its latitude at the time 
 of the passage, and then be guided by the indications of the 
 weather and the state of barometer. If it commences storming 
 the day before the passage, he may expect it much worse soon 
 after the passage ; and again, if the weather looks bad when no 
 vortex is near, he may have a steady gale setting towards a 
 storm, but no storm until the arrival of a vortex. Again, if the 
 barometer is low the day before the vortex passes, there may be 
 high barometer to the west, and the passage be attended by no 
 great commotion, as it requires time for the storm to mature, 
 and consequently its greatest violence will be to the east. If at 
 the ship the barometer is high, the vortex may still produce a 
 storm on a line of low barometer to the west, and this line may 
 reach the ship at the time of the passage. In tropical climates 
 the trouble must be looked for to the eastward ; as a storm, 
 once excited, will travel westward with that stratum of atmos- 
 phere in which the great mass o vapor is lodged, and in which, 
 of course, the greatest derangement of electric tension is pro- 
 duced. 
 
 It will now be seen that we do not admit, with Col. Reid, 
 that a storm continues in existence for a week together. Sup- 
 pose a hurricane to originate in the Antilles at the southern limits 
 of a vortex, the hurricane would die away, according to our 
 theory, if the vortex did not come round again and take up the 
 same nucleus of disturbance. On the third day the vortex is 
 found still further north, and the apparent path of the hurricane 
 
56 MECHANICAL THEORY OF STOEMS. 
 
 becomes more curved. In latitude 30 the vortex passes over 
 3 or 5 of latitude in a day ; and here being the latitude where 
 the lower atmospheric current changes its course, the storm 
 passes due north, and afterwards north-east. Now, each day of 
 the series there is a distinct hurricane, (caused by an increase 
 of energy in a particular vortex, as we have before hinted,) 
 each one overlapping on the remains of the preceding ; but in 
 each the same changes of the wind are gone through, and the 
 same general features preserved, as if it were truly a progressive 
 whirlwind, except that each vessel has the violent part of it, as 
 if she was in the southern half of the whirl. The apparent reg- 
 ularity of the Atlantic storms in direction, as exhibited by Col. 
 Reid, are owing in a great degree to the course of the Gulf 
 Stream, in which a vortex, in its successive passages in different 
 latitudes, finds more favorable conditions for the development 
 of its power, than in other parts of the same ocean ; thus show- 
 ing the importance of regarding the established character of 
 storms in each locality, as determined by observation. In this 
 connection, also, we may remark, that the meridians of greatest 
 magnetic intensity are, ceteris paribus, also the meridians of 
 greatest atmospheric commotion. The discovery of this fact is 
 due to Capt. Sabine. The cause is explained by the theory. 
 
 As it is the author's intention to embody the practical appli- 
 cation of this theory to navigation, with the necessary rules and 
 tables, in a separate work, sufficient has been said to familiarize 
 the reader with the general idea of a cause external to the earth, 
 as the active motor in all atmospheric phenomena. We will 
 therefore only allude in a general way to the principal distin- 
 guishing feature of the theory. We say, then, that the wind in 
 a storm is not in rotation, and it is a dangerous doctrine to teach 
 the navigator. We also assert as distinctly, that the wind in a 
 storm does not blow from all sides towards the centre, which is 
 just as dangerous to believe. If it were wise to pin our faith 
 to any Procrustean formula, we might endorse the following 
 
MECHANICAL THEORY OF STOEMS. 57 
 
 propositions : That at the beginning of a storm the wind is from 
 the equator towards the poles in every part of the storm ; that, 
 at a later date, another current (really a polar current deflected 
 by convection) sets in at right angles to the first one ; and that 
 at the end of the storm there is only one wind blowing at right 
 angles to the direction at the beginning. Outside the storm, 
 considered as a hundred, or two or three hundred miles in diam- 
 eter, there is, under certain limitations, a surface wind setting 
 towards the general focus of motion and condensation, and this 
 surface wind will be strongest from the westward, on account 
 of the motion of the whole atmosphere in which these other 
 motions are performed being to the eastward.* The whole phe- 
 nomenon is electrical or magnetic, or electro-magnetic or ethe- 
 real, whichever name pleases best. The vortex, by its action, 
 causes a current of induction below, from the equator, as may 
 be understood by inspecting Fig. 2, which in the northern hem- 
 isphere brings in a southerly current by convection : the regu- 
 lar circular current, however, finally penetrates below, as soon 
 as the process of induction has ceased ; and thus the polar cur- 
 rent of the atmosphere at last overcomes the equatorial current 
 in a furious squall, which ceases by degrees, and the equilibrium 
 is restored. 
 
 Every locality will have its peculiar features ; in each, the 
 prevailing wind will be at right angles to the magnetic meridian, 
 and the progress of the storm will tend to follow the magnetic 
 parallel, which is one reason why the Atlantic and Indian 
 Ocean storms have been mistaken for progressive whirlwinds. 
 When these views are developed in full, the mariner can pretty 
 certainly decide his position in the storm, the direction of its 
 progress, and its probable duration. 
 
 * In middle latitudes. 
 3* 
 
SECTION SECOND. 
 
 MECHANICAL ACTION OF THE MOON. 
 
 WE will now proceed to give the method of determining the 
 latitude of the axis of the vortex, at the time of its passage over 
 any given meridian, and at any given time. And afterwards 
 we will give a brief abstract from the record of the weather, for 
 one sidereal period of the moon, in order to compare the theory 
 with observation. 
 
 M 
 
 E 
 
 In the above figure, the circle PER represents the earth, E 
 the equator, P P' the poles, T the centre of the earth, C the 
 mechanical centre of the terral Tortex, M the moon, X X ' the 
 axis of the vortex, and A the point where the radius rector of 
 the moon pierces the surface of the earth. If we consider the 
 
MECHANICAL THEOEY OF STORMS. 59 
 
 axis of the vortex to be the axis of equilibrium in the system, it 
 is evident that T C will be to C M, as the mass of the moon to 
 the mass of the earth. Now, if we take these masses respect- 
 ively as 1 to 72.3, and the moon's mean distance at 238,650 
 miles, the mean value of T C is equal to this number, divided 
 by the sum of these masses, i. e., the mean radius vector of the 
 little orbit, described by the earth's centre around the centre of 
 gravity of the earth and moon, is equal ff^^f = 3,256 
 miles ; and at any other distance of the moon, is equal to that 
 distance, divided by the same sum. Therefore, by taking C T 
 in the inverse ratio of the mean semi-diameter of the moon to 
 the true semi-diameter, we shall have the value of C T at that 
 time. But T A is to T C as radius to the cosine of the arc A 
 R, and R R' are the points on the earth's surface pierced by 
 the axis of the vortex, supposing this axis coincident with the 
 pole of the lunar orbit. If this were so, the calculation would 
 be very short and simple ; and it will, perhaps, facilitate the in- 
 vestigation, by considering, for the present, that the two axes do 
 coincide. 
 
 In order, also, to simplify the question, we will consider the 
 earth a perfect sphere, having a diameter of 7,900 miles, equal 
 to the actual polar diameter, and therefore T A is equal to 
 3,950 miles. 
 
 In the spherical triangle given on next page, we have given the 
 point A, being the position of the moon in right ascension and de- 
 clination in the heavens, and considered as terrestrial latitude 
 and longitude. 
 
 Therefore, P A is equal to the complement of the moon's de- 
 clination, P being the pole of the earth, and L being the pole 
 of the lunar orbit ; P L is equal to the obliquity of the lunar 
 orbit, with respect to the earth, and is therefore given by find- 
 ing the true inclination of the lunar orbit at the time, equal E 
 L, (E being the pole of the ecliptic,) also the true longitude of 
 the ascending node, and the obliquity of the ecliptic P E. 
 
60 MECHANICAL THEORY OF STORMS. 
 
 ^ F 
 
 FlaS 
 
 
 
 Now, as we are supposing the axis of the vortex parallel to the 
 pole of the lunar orbit, and to pierce the earth's surface at R, 
 A R L will evidently all be in the same plane ; and, as in the 
 case of A and L, this plane passes through the earth's centre, A 
 R L must all lie in the same great circle. Having, therefore, 
 the right ascension of A, and the right ascension of L, we have 
 the angle P. This gives us two sides, and the included angle, 
 to find the side L A. But we have before found the arc A R ; 
 we therefore know L R. But in finding L A, we found both 
 the angles L and A, and therefore can find P R, which is equal 
 to the complement of the latitude sought. 
 
 We have thus indicated briefly the simple process by which 
 we could find the latitude of the axis of the central vortex, sup- 
 posing it to be always coincident with the pole of the lunar 
 orbit. The true problem is more complicated, and the principal 
 modifications, indicated by the theory, are abundantly confirmed 
 by observation. The determination of the inclination of the 
 axis of the vortex, its position in space at a given time, and the 
 law of its motion, was a work of cheerless labor for a long 
 time. He that has been tantalized by hope for years, and ever 
 on the eve of realization, has found the vision vanish, can 
 understand the feeling which proceeds from frequent disappoint- 
 ment in not finding that, whose existence is almost demonstrated ; 
 
MECHANICAL THEORY OF STORMS. 61 
 
 and more especially when the approximation differs but slightly 
 from the actual phenomena. 
 
 The chief difficulty at the outset of these investigations, 
 arose from the conflicting authority of astronomers in relation 
 to the mass of the moon. We are too apt to confound the 
 precision of the laws of nature, with the perfection of human 
 theories. Man observes the phenomena of the heavens, and 
 derives his means of predicting what will be, from what has 
 been. Hence the motions of the heavenly bodies are known to 
 within a trifling amount of the truth ; but it does not follow that 
 the true explanation is always given by theory. If this were so, 
 the mass of the moon (for instance) ought to be the same, whether 
 deduced from the principle of gravitation or from some other 
 source. This is not so. Newton found it ^ of that of the 
 earth. La Place, from a profound theoretical discussion of the 
 tides, gave it as j^.g-, while from other sources he found a neces- 
 sity of diminishing it still more, to ^, and finally as low as Jj. 
 Bailly, Herschel, and others, from the nutation of the earth's axis, 
 only found j 1 ^ and the Baron Lindenau deduced the mass from 
 the same phenomenon Jg-. In a very recent work by Mr. Hind, 
 he uses this last value in certain computations, and remarks, that 
 we shall not be very far wrong in considering it as as j\ of the 
 mass of the earth. This shows the uncertainty of the matter in 
 1852. If astronomy is so perfect as to determine the parallax of 
 a fixed star, which is almost always less than one second, why is 
 it that the mass of the moon is not more nearly approximated ? 
 Every two weeks the sun's longitude is affected by the position 
 of the moon, alternately increasing and diminishing it, by a 
 quantity depending solely upon the relative mass of the earth 
 and moon, and is a gross quantity compared to the parallax of 
 a star. So, also, the horizontal parallax the most palpable of 
 all methods taken by different observers at Berlin, and the 
 Cape of Good Hope, (a very respectable base line, one would 
 suppose,) makes the mass of the moon greater than its value 
 
62 MECHANICAL THEOKY OF STORMS. 
 
 derived from nutation ; the first giving about -y 1 ^ the ^ a 
 T \^. Does not this declare that it is unsafe to depend too 
 absolutely on the strict wording of the Newtonian law of gravi- 
 tation. Happily our theory furnishes us with the correct value 
 of the moon's mass, written legibly on the surface of the earth ; 
 and it comes out nearly what these two phenomena always gave 
 it, viz. : T J ^ of that of the earth. In another place we shall 
 inquire into the cause of the discrepancy as given by the nuta- 
 tion of the earth. 
 
 MOTION OF THE AXIS OF THE VORTEX. 
 
 If the axis of the terral vortex does not coincide with the axis 
 of the lunar orbit, we must derive this position from observation, 
 which can only be done by long and careful attention. This 
 difficulty is increased by the uncertainty about the mass of the 
 moon, already alluded to, and by the fact that there are three 
 vortices in each hemisphere which pass over twice in each month, 
 and it is not always possible to decide by observation, whether 
 a vortex is ascending or descending, or even to discriminate be- 
 tween them, so as to be assured that this is the central descend- 
 ing, and that the outer vortex ascending. A better acquaint- 
 ance, however, with the phenomenon, at last dissipates this un- 
 certainty, and the vortices are then found to pursue their course 
 with that regularity which varies only according to law. The 
 position of the vortex (the central vortex is the one under con- 
 sideration) then depends on the inclination of its axis to the axis 
 of the earth, and the right ascension of that axis at the given 
 time. For we shall see that an assumed immobility of the axis 
 of the vortex, would be in direct collision with the principles of 
 the theory. 
 
 Let the following figure represent a globe of wood of uniform 
 density throughout. Let this globe be rotated round the axis. 
 It is evident that no change of position of the axis would be 
 
MECHANICAL THEORY OF STORMS. 63 
 
 71 
 
 produced by the rotation, If we add two equal masses of lead 
 at m and m', on opposite sides of the axis, the globe is still in 
 equilibrium, as far as gravity is concerned, and if perfectly 
 spherical and homogeneous it might be suspended from its centre 
 in any position, or assume indifferently any position in a vessel 
 of water. If, however, the globe is now put into a state of rapid 
 rotation round the axis, and then allowed to float freely in the 
 water, we perceive that it is no longer in a state of equilibrium. 
 The mass m being more dense than its antagonist particle at 
 w, and having equal velocity, its momentum is greater, and it 
 now tends continually to pull the pole from its perpendicular, 
 without affecting the position of the centre. The same effect is 
 produced by m', and consequently the axis describes the surface 
 of a double cone, whose vertices are at the centre of the globe. 
 If these masses of lead, had been placed at opposite sides of the 
 axis on the equator of the globe, no such motion would be pro- 
 duced ; for we are supposing the globe formed of a hard and 
 unyielding material. In the case of the ethereal vortex of the 
 earth, we must remember there are two different kinds of mat- 
 ter, one ponderable, the other not ponderable ; yet both sub- 
 ject to the same dynamical laws. If we consider the axis of 
 the terral vortex to coincide with the axis of the lunar orbit, the 
 moon and earth are placed in the equatorial plane of the vortex, 
 
64 MECHANICAL THEORY OF STORMS. 
 
 and consequently there can be no derangement of the equi- 
 librium of the vortex by its own rotation. But even in this case, 
 seeing that the moon's orbit is inclined to the ecliptic, the gravi- 
 tating power of the sun is exerted on the moon, and of neces- 
 sity she must quit the equatorial plane of the vortex ; for the 
 sun can exert no influence on the matter of the vortex by his 
 attracting power. The moment, however, the moon has left the 
 equatorial plane of the vortex, the principle of momentum comes 
 into play, and a conical motion of the axis of the vortex is pro- 
 duced, by its seeking to follow the moon in her monthly revolu- 
 tion. This case is, however, very different to the illustration we 
 gave. The vortex is a fluid, through which the moon freely 
 wends her way, passing through the equatorial plane of the 
 vortex twice in each revolution. These points constitutes the 
 moon's nodes on the plane of the vortex, and, from the principles 
 laid down, the force of the moon to disturb the equilibrium of 
 the axis of* the vortex, vanishes at these points, and attains a 
 maximum 90 from them. And the effect produced, in passing 
 from her ascending to her descending node, is equal and con- 
 trary to the effect produced in passing from her descending to 
 her ascending node, reckoning these points on the plane of 
 the vortex. 
 
 INCLINATION OF THE AXIS. 
 
 By whatever means the two planes first became permanently 
 inclined, we see that it is a necessary consequence of the admis- 
 sion of these principles, not only that the axis of the vortex 
 should be drawn aside by the momentum of the earth and 
 moon, ever striving, as it were, to maintain a dynamical balance 
 in the system, in accordance with the simple laws of motion, and 
 ever disturbed by the action of gravitation exerted on the 
 grosser matter of the system ; but also, that this axis should 
 follow, the axis of the lunar orbit, at the same mean inclination, 
 during the complete revolution of the node. The mean inclina- 
 
MECHANICAL THEORY OF STORMS. 
 
 65 
 
 tion of the two axes, determined by observation, is 2 45', and 
 the monthly equation, at a maximum, is about 15', being a plus 
 correction in the northern hemisphere, where the moon is be- 
 tween her descending and ascending node, reckoned on the 
 plane of the vortex, and a minus correction, when between her 
 ascending and descending node. And the mean longitude of 
 the node will be the same as the true longitude of the moon's 
 orbit node, the maximum correction for the true longitude 
 being only about 5 db. 
 
 In the following figure, P is the pole of the earth ; E the 
 pole of the ecliptic ; L the pole of the lunar orbit ; V the mean 
 position of the pole of the vor- 
 tex at the time ; the angle P 
 E L the true longitude of the 
 pole of the lunar orbit, equal 
 to the true longitude of the 
 ascending node 90. V L 
 is therefore the mean inclina- 
 tion = 2 45' ; and the little 
 circle, the orbit described by 
 the pole of the vortex twice in 
 each sidereal revolution of the 
 moon. The distance of the 
 pole of the vortex from the 
 mean position V, may be ap- 
 proximately estimated, by mul- 
 tiplying the maximum value 
 15' by the sine of twice the 
 moon's distance from the node 
 of the vortex, or from its mean 
 position, viz. : the true longi- 
 tude of the ascending node of 
 the moon on the ecliptic. 
 From this we may calculate the true place of the node, the true 
 
66 
 
 MECHANICAL THEOEY OF STORMS. 
 
 obliquity, and the true inclination to the lunar orbit. Having 
 indicated the necessity for this correction, and its numerical co- 
 efficient, we shall no longer embarrass the computation by such 
 minutiae, but consider the mean inclination as the true inclina- 
 tion, and the mean place of the node as the true place of the 
 node, and coincident with the ascending node of the moon's 
 orbit on the ecliptic. 
 
 POSITION OF THE AXIS OF THE VORTEX. 
 
 It is now necessary to prove that the axis of the vortex will 
 still pass through the centre of gravity of the earth and moon. 
 
 Let X X now represent the axis of the lunar orbit, and C the 
 centre of gravity of the earth and moon. X' X' the axis of the 
 vortex, and K C R the inclination of this axis. Then from 
 
 similarity C t 
 
 but T t 
 
 That is 'T t 
 
 M m 
 Mm 
 
 C m 
 
 Moon's mass 
 TO 
 
 M m 
 
 Earth's mass. 
 MC. 
 
 Therefore the system is still balanced ; and in no other point 
 but the point C, can the intersection of the axes be made with- 
 out destroying this balance. 
 
MECHANICAL THEORY OF STORMS. 
 
 67 
 
 It will be observed by inspecting the figure, that the arc 
 R' K' is greater than the arc R K. That the first increases the 
 arc A R, and the second diminishes that arc. The arc R' K' is 
 a plus correction therefore, and the smaller arc R K a minus 
 correction. If the moon is between her descending and as- 
 cending node, (taking now the node on the ecliptic,) the correc- 
 tion is negative, and we take the smaller arc. If the moon is 
 between her ascending and descending node, the correction is 
 positive, and we take the larger arc. If the moon is 90 from 
 the node, the correction is a maximum. If the moon is at the 
 node, the correction is null. In all other positions it is as the 
 sine of the moon's distance from the nodes. We must now find 
 the maximum value of these arcs of correction corresponding to 
 the mean inclination of 2 45 '. 
 
 To do this we may reduce T C to T t in the ratio of radius to 
 cosine of the inclination, and taking T S for radius. 
 
 Fiq 9 
 
 T C X Cos &c. (inclination 2 45'). 
 
 - w equal the cosine of the 
 
 arc 
 
 S K' and S K' + A S = A K' and A K' - A R' = R' K'. 
 But from the nature of the circle, arc R K -f- arc R' K' = angle 
 R C K + angle R' C K', or equal to double the inclination ; and 
 therefore, by subtracting either arc from double the inclination, 
 we may get the other arc. 
 
68 MECHANICAL THEOEY OF STORMS. 
 
 The maximum value of these arcs can, however, be found by 
 a simple proportion, by saying ; as the arc A R, plus the incli- 
 nation, is to the inclination, so is the inclination to the difference 
 between them ; and therefore, the inclination, plus half the dif- 
 ference, is equal the greater arc, and the inclination, minus half 
 the difference, is equal the lesser ; the greater being positive, 
 and the lesser negative. 
 
 Having found the arc A R, and knowing the moon's distance 
 from either node, we must reduce these values of the arcs R K 
 and R' K' just found, in the ratio of radius to the sine of that 
 distance, and apply it to the arc A R or A' R', and we shall 
 get the first correction equal to the arc A K or A K'. 
 
 Call the arc A R = a 
 
 " inclination = n 
 
 " distance from the node = d 
 
 " arcAK = k 
 
 and supposing the value of A K be wanted for the northern 
 hemisphere when the moon is between her descending and as- 
 cending node, we have 
 
 Tc = a - 
 
 ( a + 
 n 
 
 If the moon is between her ascending and descending node, 
 then 
 
 (' 
 
 sine?. 
 
 R 
 
 The computation will be shorter, however, if we merely re- 
 duce the inclination to the sine of the distance from the node 
 for the first correction of the arc A R, if we neglect the semi- 
 
MECHANICAL THEORY OF STOEMS. 69 
 
 monthly motion of the axis ; for this last correction diminishes 
 the plus corrections, and the first one increases it. If, therefore, 
 one is neglected, it is better to neglect the other also ; especially 
 as it might be deemed affectation to notice trifling inequalities 
 in the present state of the elements of the question. 
 
 There is one inequality, however, which it will not do to neg- 
 lect. This arises from the displacement of the axis of the vortex. 
 
 DISPLACEMENT OF THE AXIS. 
 
 We have represented the axis of the terral vortex as con- 
 tinually passing through the centre of gravity of the earth and 
 moon. Now, by following out the principles of the theory, we 
 shall see that this cannot be the case, except when the moon is 
 in quadrature with the sun. To explain this : 
 
 Let the curve passing through C represent a portion of the 
 orbit of the earth, and S the sun. From the principles laid 
 down, the density of the ethereal medium increases outward as 
 the square roots of the distances from the sun. Now, if we 
 consider the circle whose centre is C to represent the whole 
 terral vortex, it must be that the medium composing it varies 
 also in density at different distances from the sun, and at 
 the same time is rotating round the centre. That half of the 
 
70 
 
 MECHANICAL THEOEY OF STORMS. 
 
 Fig. 11. 
 
 vortex which is exterior to the orbit of the earth, being most 
 dense, has consequently most inertia, and if we conceive the 
 centre of gravity of the earth and moon to be in the orbit (as it 
 must be) at C, there will not be dynamical balance in the 
 terral system, if the centre of the vortex is also found at C. To 
 preserve the equilibrium the centre of the vortex will necessarily 
 come nearer the sun, and thus be found between T and C, T 
 representing the earth, and the moon, and C the centre of 
 gravity of the two bodies. If the moon is in opposition, the 
 centre of the vortex will fall between the centre of gravity and 
 
 the centre of the earth, and 
 have the apparent effect of 
 diminishing the mass of the 
 moon. If, on the other hand, 
 the moon is in conjunction, 
 the centre of the vortex will 
 fall between the centre of 
 gravity and the moon, and 
 have the apparent effect of in- 
 creasing the mass of the moon. 
 If the moon is in quadrature, 
 the effect will be null. The co- 
 efficient of this inequality is 90', 
 and depends on the sun's dis- 
 tance from the moon. When 
 the moon is more than 90 from 
 the sun, this correction is pos- 
 itive, and when less than 90 
 from the sun, it is negative. 
 If we call this second correc- 
 tion C, and the moon's dis- 
 tance from her quadratures 
 90' X Sin Q. 
 
 Q, we have the value of C = 
 
 II 
 
MECHANICAL THEOKY OF STORMS. 71 
 
 This correction, however, does not affect the inclination 
 of the axis of the vortex, as will be understood by the 
 subjoined figure. If the moon is in opposition, the axis 
 of the vortex will not pass through C, but through C', and 
 Q Q' will be parallel to K K'. If the moon is in conjunction, 
 the axis will be still parallel to K K', as represented by the 
 dotted line q q'. The correction, therefore, for displacement, 
 is equal to the arc K Q or K <?, and the correct position of the 
 vortex on the surface of the earth at a given time will be at the 
 points Q or q, and Q' or q', considering the earth as a sphere. 
 
 In the spherical triangle A P V, P is the pole of the earth, V 
 the pole of the vortex, A the point of the earth's surface pierced 
 by the radius vector of the moon, A Q is the corrected arc, and 
 P V is the obliquity of the vortex. Now, as the axis of the 
 vortex is parallel to the pole V, and the earth's centre, and the 
 line M A also passes through the earth's centre, consequently 
 
 M 
 
 A Q V will all lie in the same great circle, and as P V is 
 known, and P A is equal to the complement of the moon's 
 declination at the time, and the right ascensions of A and V 
 give the angle P, we have two sides and the included angle to 
 find the rest, P Q being the complement of the latitude sought. 
 We will now give an example of the application of these 
 principles. 
 
72 
 
 MECHANICAL THEORY OF STORMS. 
 
 Example.* Required the latitude of the central vortex at 
 the time of its meridian passage in longitude 88 50' west, July 
 2d, 1853. 
 
 CENTRAL VORTEX ASCENDING. 
 
 Greenwich time of passage 2d. 3h. 1m. 
 
 Mean longitude of moon's node 78 29' 
 
 True " " ...... 79 32 
 
 Mean inclination of lunar orbit 59 
 
 True " " . 5 13 
 
 Obliquity of ecliptic 23 27 32" 
 
 Mean inclination of vortex 2 45 
 
 Then in the spherical triangle P E V. 
 
 P E .... is equal .... 23 27' 32" 
 
 EV . . . . " .... 7 58 
 
 E .... " .... 100 28 
 
 P .... " .... 18 5 7 
 
 PV . . . . " .... 26 2 32 
 
 Calling P the polar angle and P V the obliquity of vortex. 
 
 
 * For convenience to those wishing to verify the calculatio n of these 
 triangles, we have put down each side and angle as found. Also, as an 
 aid to the navigator. 
 
MECHANICAL THEORY OF STORMS. 73 
 
 To find the arc A R. 
 
 By combining the two proportions already given, we have 
 by logarithms : 
 
 M. R. V. minor 3256 Log. 3.512683 
 
 M. S. D. of moon = 940"" 2.973128 
 
 P. S. D. of earth = 3950 A. C. 6.403403 
 
 Radius ........... 10.000000 
 
 T. S. D. of moon . . . 885".5 A. C. 7.052811 
 
 Log. Cosine arc A R 28 57' 3" 9.942025 
 
 As the only variable quantity in the above formula is the 
 " True" serai-diameter of the moon at the time, we may add 
 the Constant logarithm 2.889214 to the arithmetical comple- 
 ment of the logarithm of the true semi-diameter, and we have 
 in two lines the log. cosine of the arc A R. 
 
 We must now find the arc R K equal at a maximum to 
 2 45'. The true longitude of the moon's node being 79 32', 
 and the moon's longitude, per Nautical Almanac, being 58 30', 
 the distance from the node is 21 2', therefore, the correction is 
 
 To find the correction for displacement. 
 
 True longitude of sun at date ........ 100 30 f 
 
 " of moon " ........ 58 30 
 
 Moon's distance from quadrature ....... 48 
 
 As the moon is less than 90 from the sun this correction is also 
 negative, or 
 
 Arc A R = 
 
 28 57' 3" 
 
 RK = - 
 
 39 13 
 
 Kg = - 
 
 1 6 46 
 
 Sum = 
 
 26 51 4 = 
 
 4 = corrected arc A Q. 
 4 
 
74 MECHANICAL THEORY OF STORMS. 
 
 We have now the necessary elements in the Nautical Alma- 
 nac, which we must reduce for the instant of the vortex passing 
 the meridian in Greenwich time. 
 
 same time 
 
 July 2d. 
 
 Meridian passage, local time, at . . 
 " in Greenwich time . 
 
 Right ascension . . 
 Declination north . . 
 Obliquity of the vortex 
 Polar angle . . . 
 ArcAQ .... 
 
 9h. 5m. A. M. 
 
 2d. 3h. 1m. 
 56 42' 45" 
 18 00 1 
 26 2 32 
 18 5 7 
 26 51 4 
 
 P A = 71 59' 59" 
 P V 26 2 32 
 VA = 89 3 
 VQ = 62 11 56 
 PQ = 47 14 22 
 
 P = 128o 37' 38" 
 
 V= 47 
 A = 20 
 Q = 26 
 
 59 44 
 
 3 42 
 
 22 55 
 
 Latitude of Q on the sphere = 42 45' 38" 
 
 CORRECTION FOR PROTUBERANCE. 
 
 We have hitherto considered the earth a perfect sphere with 
 a diameter of 7,900 miles. It is convenient to regard it thus, 
 and afterwards make the correction for protuberance. We will 
 
MECHANICAL THEORY OF STORMS. 
 
 75 
 
 now indicate the process for obtaining this correction by the aid 
 of the following diagram. 
 
 Let B bisect the chord 
 Z Z'. Then, by geometry, 
 the angle F Q Y is equal to 
 the angle B T F, and the 
 protuberance F Y is equal 
 the sine of that angle, making 
 Q F radius. This angle, 
 made by the axis of the vor- 
 tex and the surface of the 
 sphere, is commonly between 
 30 and 40, according as 
 the moon is near her apogee 
 or perigee; and the correc- 
 tion will be greatest when 
 the angle is least, as at the 
 apogee. At the equator, the 
 whole protuberance of the 
 earth is about 13 miles. 
 Multiply this by the cosine 
 of the angle and divide by 
 the sine, and we shall get 
 the value of the arc Q Y 
 for the equator. For the smallest angle, when the correction is 
 a maximum, this correction will be about 20' of latitude at the 
 equator ; for other latitudes it is diminished as the squares of 
 the cosines of the latitude. Then add this amount to the lati- 
 tude E Q, equal the latitude E Y. This, however, is only cor- 
 rect when the axis of the vortex is in the same plane as the axis 
 of the earth ; it is, therefore, subject to a minus correction, 
 which can be found by saying, as radius to cosine of obliquity 
 so is the correction to a fourth the difference of these correc- 
 tions is the maximum minus correction, and needs reducing in 
 
76 MECHANICAL THEOKY OF STORMS. 
 
 the ratio of radius to the cosine of the angle of the moon's dis- 
 tance from the node ; but as it can only amount to about 2' at 
 a maximum under the most favorable circumstances, it is not 
 necessary to notice it. The correction previously noticed is on 
 the supposition that the earth is like a sphere having T F for 
 radius ; as it is a spheroid, we must correct again. From the 
 evolute, draw the line S F, and parallel to it, draw T W ; then 
 E W is the latitude of the point F on the surface of the spheroid. 
 This second correction is also a plus correction, subject to the 
 same error as the first on account of the obliquity, its maximum 
 value for an angle of 30 is about 6', and is greatest in latitude 
 
 , t0 , tl , 6' X sin (double the lat.) 
 45 ; for other latitudes, it is equal -~r 
 
 The three principal corrections for protuberance may be esti- 
 mated from the following table, calculated for every 15 of lati- 
 tude for an angle of 30, or when the correction is greatest. 
 
 Latitude. 1st Corr. 2d Corr. 3d Corr. 
 
 +20' +0 2 
 
 15 +19 +3 1.5 
 
 30 +15 +5 1.5 
 
 45 +10 +6 1. 
 
 60 +5 +5 1 
 
 70 +1 +3 0.5 
 
 We can now apply this correction to the latitude of the vortex 
 just found : 
 
 Latitude on the sphere 42 45' 38" n. 
 
 Correction for protuberance . . . . + 14 22 
 Correct latitude . ~43 00 00 
 
 MILWAUKIE STORM, JULY 2. 
 
 As this example was calculated about ten days before the 
 actual date, we have appended an extract from the Milwaukie 
 papers, which is in the same longitude as Ottawa, in which place 
 
MECHANICAL THEOKY OF STORMS. 77 
 
 the calculation was made.' It is needless to remark that the 
 latitude of Milwaukie corresponds to the calculated latitude of 
 the centre of the vortex. It is not intended, however, to convey 
 the idea that the central line is always the most subject to the 
 greatest violence a storm may have several centres or nuclei 
 of disturbance, which are frequently waning and reviving as the 
 storm progresses. Generally speaking, however, the greatest 
 action is developed along the line previously passed over by the 
 axis of the vortex. 
 
 "SUMMIT, Waukesha Co., Wis., July 4, 1853. 
 
 " Our town, on Saturday, the 2d, was visited by a terrible storm, 
 which will long be remembered by those who witnessed its effects 
 and suffered from its fury. It arose in the south-west, and came 
 scowling in blackness, sufficient to indicate its anger, for the 
 space of eighty or a hundred rods in width, covering our usually 
 quiet village ; and for nearly half an hour's duration, the rain 
 fell in torrents, the heavens blazed with the lightning's flashes, 
 trees fell and were uprooted by the fury of the blast, fragments 
 of gates and of buildings, shingles, roof-boards, rafters, circled 
 through the air, the playthings of the wind and buildings 
 themselves were moved entire from their foundations, and de- 
 posited at different distances from their original positions. A 
 barn, fifty-five feet square on the ground, owned by Mr. B. R. 
 Hinckley, is moved from its position some ten feet to the east- 
 ward ; and a house, some fifteen by eighteen feet on the ground, 
 owned by the same person, fronting the east, was driven by the 
 wind to the opposite side of the street, and now fronts nearly 
 west ; and what is most strange, is that the grass, in the route 
 the house must have passed over, stands straight as usual, and 
 gives no evidence that the building was pushed along on the 
 ground. A lady running from a house unroofed by the storm, 
 took an aerial flight over two fences, and finally caught against 
 a tree, which arrested her passage for a moment only, when, 
 giving way, she renewed her journey for a few rods, and was 
 
78 MECHANICAL THEORY OF STORMS. 
 
 set down unhurt in Mr. O. Reed's wheat field, where, clinging 
 to the growing grain, she remained till the gale went by."* 
 
 The weather at this place is briefly recorded in the accom- 
 panying abstract from the journal, as well as in an extract from 
 a note to Professor Henry, of the Smithsonian Institution, from 
 a friend of the author's, who has long occupied a high official 
 station in Illinois. But such coincidences are of no value in 
 deciding on the merits of such a theory. It must be tried be- 
 fore the tribunal of the world, and applied to phenomena in 
 other countries with success, before its merits can be fully ap- 
 preciated. The accompanying record, therefore, is only given 
 to show how these vortices render themselves apparent, and 
 what ought to be observed, and also to exhibit the order of their 
 recurrence and their positions at a given time. 
 
 Extractof a note addressed to the Secretary of the Smithsonian 
 
 Institution, by Hon. John Dean Caton, on this subject. 
 " As a striking instance of the remarkable coincidences con- 
 firmatory of these calculations, I will state, that on Friday, the 
 first of July last, this gentlemanf stated that on the next day a 
 storm would pass north of us, being central a little south of Mil- 
 waukie, and that he thought, from the state of the atmosphere, 
 the storm would be severe, and that its greatest violence would 
 be felt on the afternoon or night of the next day. At this time 
 the weather was fine, without any indications of a storm, so far 
 as I could judge. At noon on the following day he pointed out 
 the indications of a storm at the north and north-west, consist- 
 ing of a dark, hazy belt in that direction, extending up a few 
 degrees above the horizon, although so indistinct as to have 
 escaped my observation. At five o'clock a violent storm visited 
 us, which lasted half an hour, although a clear sky was visible 
 at the south the whole time. On Monday morning I learned, 
 from the telegraph office at Chicago, that early on Saturday 
 * Daily Wisconsin, July 7. f The author. 
 
MECHANICAL THEORY OF STOEMS. 79 
 
 afternoon communication with Milwaukie had been interrupted 
 by atmospheric electricity, and that the line had been broken 
 by a storm." 
 
 NEW YORK STORM. 
 
 After this was written, the author discovered that the vortex 
 was equally violent the day before at New York, July 1st, 1853. 
 An account of this storm follows. The calculation has not been 
 made, but it is easy to perceive that the latitude of the vortex, 
 on July 1st, must be very nearly that of New York being in 
 latitude 43 next day and ascending. 
 
 "At a meeting of the American Association, convened at 
 Cleveland, Professor Loomis presented a long notice of the ter- 
 rible hail storm in New York on the 1st of July. He traced its 
 course, and minutely examined all the phenomena relating to it, 
 from a mile and a half south-east of Paterson, N. J., to the east 
 side of Long Island, where it appeared nearly to have spent its 
 force. It passed over the village of Aqueenac, striking the 
 Island of New York in the vicinity of the Crystal Palace. It 
 was not much more than half a mile wide. The size of the 
 hail-stones was almost incredibly large, many of them being as 
 large as a hen's egg, and the Professor saw several which he 
 thought as large as his fist. Some of them weighed nearly half 
 a pound. The principal facts in relation to this storm were 
 published at the time, and need not be repeated. The discus- 
 sions arising among the members as to the origin and the size 
 of these hail-stones, and the phenomena of the storm, were ex- 
 ceedingly interesting. They were participated in by Professors 
 Heustus and Hosford, of Cambridge University, Professor Loo- 
 mis, and Professors Bache and Redfield. The latter two gentle- 
 men differ somewhat, we should suppose radically, in their 
 meteorological theories, and had some very sharp but very 
 pleasant " shooting" between them."* 
 
 * Chicago Democrat. 
 
80 MECHANICAL THEORY OF STORMS. 
 
 CENTRAL VORTEX DESCENDING. 
 
 We will now make the calculation for the central vortex 
 descending, for longitude 88 50' west, August 7, 1853, put- 
 ting down the necessary elements for the time of the meridian 
 passage in order : 
 
 Meridian passage in local time at ... 2h. 25m. p. M. 
 
 " " in Greenwich time ... 7d. 8h. 18m. 
 Mass of the moon 7 i.j M. R. V. minor . . 3,256 miles. 
 Obliquity of the vortex, same time . . . 26 5' 0" 
 Polar angle of " " .... 17 41 47 
 
 True longitude of moon's node " . . . . 78 42 
 " inclination of orbit " . . . . 55 
 
 " longitude of the sun " . . . . 135 20 
 
 Moon's longitude " . . . . 169 44 
 
 " distance from node " . . . . 91 2 
 
 " distance from quadrature " . . . . 55 36 
 " true semi-diameter " . . . . 943 
 
 " right ascension " . . . . 172 30 
 
 " declination north " . . . . 8 42 20 
 
 Constant logarithm . . . 2.889214 
 Arith. comp. of log. of 943 . 7.025488 
 Log. cos. arc. A R . . . . 9.914702 = 34 44' 48" 
 1st. . correction, + 2 45 
 2d. correction, 1 14 15 
 
 Corrected arc A Q = "36 15 33 
 
 P A . . . . = 81 17' 40"~ 
 
 PV . . . . = 26 5 
 
 P ...... =s 115 11 47 
 
 V . . . . = 63 34 26 
 
 A . . . . = 23 28 24 
 
 AV . . . . = 92 48 39 
 
 Q = 31 32 18 
 
MECHANICAL THEORY OF STORMS. 81 
 
 Complement of lat. = P Q == 48 49' 41" 
 The latitude is therefore for 
 
 the earth, as a sphere . 41 10 18 
 
 Correction for protuberance + 0160 
 
 True latitude of centre . . ~41 26 18 north. 
 
 Latitude of Ottowa 41 20 " 
 
 Vortex passed 6 18 north of Ottowa. 
 
 As this was nearly a central passage, and as the influence was 
 less extensive than usual, on account of great atmospheric press- 
 ure with a low dew point, the central disturbance could the 
 more readily be located, and was certainly to the north, and but 
 a few miles. The following is from the record of the weather : 
 
 August 6th. Very fine and clear all day ; wind from S.-W. ; 
 a light breeze ; 8 P. M. frequent flasnes of lightning in the 
 northern sky ; 1 P. M. a low bank of dense clouds in north, 
 fringed with cirri, visible during the flash of the lightning ; 1 2 
 p. M. same continues. 
 
 7th. Very fine and clear morning ; wind S.-W. moderate ; 
 noon, clouds accumulating in the northern half of the 
 sky ; wind fresher S.-W. ; 3 p. M. a clap of thunder over- 
 head, and black cumuli in west, north, and east ; 4 p. M. much 
 thunder, and scattered showers ; six miles west rained very 
 
82 MECHANICAL THEOEY OF STOKMS. 
 
 heavily ; 6 P. M. the heavy clouds passing over to the south ; 10 
 p. M. clear again in north. 
 
 August 8th. Clear all day ; wind the same (S.-W.) ; a hazy 
 bank visible all along on southern horizon. 
 
 This was not a storm, in the ordinary acceptation of the term ; 
 but the same cause, under other circumstances, would have pro- 
 duced one ; and let it be borne in mind, that although the 
 moon is the chief disturbing cause, and the passages of the vor- 
 tices are the periods of greatest commotion in both settled and 
 unsettled weather, still the sun is powerful in predisposing the 
 circumstances, whether favorable or unfavorable ; and as there 
 is no periodic connection between the passage of a vortex and 
 the concurrence of the great atmospheric waves, it will, of course, 
 happen only occasionally that all the circumstances will con- 
 spire to make a storm. There are also other modifying causes, 
 to which we have not yet alluded, which influence the storms 
 at different seasons of the year, exaggerating their activity in 
 some latitudes, and diminishing it in other latitudes. In this 
 latitude, the months of May, June, and July are marked by 
 more energetic action than August, September, and October. 
 The activity of one vortex also, in one place, seems to modify 
 the activity of another vortex in another place. But the great 
 question to decide is : Do these vortices really exist ? Do they 
 follow each other in the order indicated by the theory ? Do 
 they pass from south to north, and from north to south, at the 
 times indicated by the theory ? Do they obey, in their monthly 
 revolutions, a mathematical law connecting them with the 
 motions of the moon ? We answer emphatically, Yes ! And 
 the non-discovery of these facts, is one of the most humiliating 
 features of the present age. 
 
MECHANICAL THEOEY OF STOKMS. 
 
 OTTOWA STORM, DECEMBER 22, 1852. 
 
 To show that the same calculations are applicable for other 
 times, we will make the calculation for the centre ascending, for 
 the 22d December, 1852, taking the following elements : 
 Moon's mer. passage, Dec. 22d . . . 15h. 16m. G. time. 
 " right ascension, same time . . 51 57' 
 " declination north . 15 42 
 
 " distance from node . . . 
 " " " quadrature . 
 
 . 37 
 
 . 52 
 
 Which gives the arc A R ... 
 1st correction .... . . 
 
 . 29 5 
 . 1 51 
 
 2d " 
 
 . 4-1 11 
 
 
 
 Corrected arc A Q 28 25 
 
 And the latitude at the time of the meridian passage = 42 
 north, or about forty miles north of Ottawa. 
 
 Abstract from the record : 
 
 *Dec. 21st, 1852. Wind N.-E., fine weather. 
 
 Dec. 22d. Thick, hazy morning, wind east, much lighter in 
 S.-E. than in N.-W. ; 8 A. M., a clear arch in S.-E. getting 
 more to south ; noon, very black in W. N.-W. ; above, a broken 
 layer of cir. cumulus, the sun visible sometimes through the 
 waves ; wind round to S.-E., and fresher ; getting thicker all 
 day; 10 p. M., wind south, strong; thunder, lightning, and 
 heavy rain all night, with strong squalls from south. 
 
 Dec. 23d. Wind S.-W., moderate, drizzly day; 10 p. M., 
 wind west, and getting clearer. 
 
 The next day the vortex passed the latitude of Montreal (the 
 moon being on the meridian about 10 p. M.) 
 
 * This was also calculated before the event. 
 
84 MECHANICAL THEOKY OF STORMS. 
 
 MAGNETIC STORM, DECEMBER 23, 1852. 
 
 In the July number of Vol. XVI. of Silliman's Journal, we 
 find certain notices of the weather in 1852, by Charles Small- 
 wood, of St. Martins, nine miles east of Montreal. He men- 
 tions " two remarkable electrical storms (which) occurred on 
 the 23d and 31st of December, (in which) sparks -$ of an 
 inch were constantly passing from the conductor to the dis- 
 charger for several hours each day." At 10 p. M. (23d) the 
 vortex passed over Montreal, and again descending on the 31st 
 North, and was visible at Ottowa on the morning of the 
 1st of January, with southerly wind setting towards it. On the 
 29th of December, Mr. Small wood records "a low auroral arch, 
 sky clear." On the 29th, the vortex was 5 to the northward 
 of Montreal, and the aurora was consequently low the 
 brightest auroras being when the vortex is immediately north 
 without storm, or one day to the northward, although we have 
 seen it very low when the vortex was three days to the north, 
 and no other vortex near. 
 
 LIVERPOOL STORM. 
 
 On the night of the 24th of December, the same central 
 vortex ascending passed between Cape Clear and Liverpool. 
 
 On the 25th, at midnight, the vortex passed to the north of 
 Liverpool : its northerly progress being very slow, being con- 
 fined for three days between the parallel of Liverpool and its 
 extreme northern limit in latitude about 57. The accompany- 
 ing account of the weather will show the result of a long- 
 continued disturbance near the same latitude : 
 
 The Baltic, three days out from Liverpool, encountered the 
 vortex on the night of the 23d. On the morning of the 25th, 
 very early, the gale commenced at Liverpool, and did much 
 damage. On the 26th, the vortex attained its northern limit ; 
 
MECHANICAL THEORY OF STORMS. 85 
 
 "but we have not been able to procure any account of its effects 
 to the northward of Liverpool, although there can be but little 
 doubt that it was violent on the coast of Scotland on the 26th ; 
 for the next day (27th) the vortex having made the turn, 
 was near the latitude of Liverpool, and caused a tremendous 
 storm, thus showing a continued state of activity for several 
 days, or a peculiarly favorable local atmosphere in those parts. 
 
 It is very probable, also, that there was a conjunction of the 
 central and inner vortex on the 2*7th. The inner vortex pre- 
 cedes the central in passing latitude 41; but as the mean 
 radius of its orbit is less than that of the central, it attains to a 
 higher latitude, and has, consequently, to cross the path of the 
 central, in order again to precede it descending in latitude 41. 
 As a very trifling change in the elements of the problem will 
 cause great changes in the positions of the vortices on the 
 surface of the earth, it cannot now be asserted that such a 
 conjunction did positively occur at that time ; but, it may be 
 suspected, that a double disturbance would produce a greater 
 commotion, or, in other words, a more violent storm. 
 
 It is on this account, combined with other auxiliary causes, 
 that the vicinity of Cape Horn is so proverbially stormy, as 
 well as for the low standard of the barometer in that latitude, 
 it is the stationary point of the vortices in ordinary positions of 
 the nodes and perigee of the moon. We have already alluded 
 to the fact, that none of the vortices scarcely ever pass much 
 beyond latitude 80, and then only under favorable circum- 
 stances, so that we ought to infer, that gales in high latitudes 
 should set from the poles towards the storms in lower latitudes. 
 This is, no doubt, the fact, but, nevertheless, a hard southerly 
 blow may possibly occur in high northern latitudes, if a storm 
 should be raging very violently in a lower latitude on the 
 opposite side of the pole, the distance across the circle of 80 
 being only about 1,400 miles. As the different vortices have a 
 different limit in latitude every year, the determination of this 
 
86 
 
 MECHANICAL THEOEY OF STORMS. 
 
 turning point is obviously of great practical utility, as the fact 
 may yet be connected with other phenomena, so as to give us 
 the probable character of the polar ice at any assigned time. 
 On this point we have more to say. 
 
 PASSAGES OF ALL THE VORTICES. 
 
 Our remarks have hitherto been confined to the central 
 vortex. We shall now show from the record, that the other 
 vortices are as effective in deranging the equilibrium of our 
 atmosphere. In the following table we have given the passages 
 of the different vortices, which will serve as their true positions 
 within moderate limits, to calculate from, for all future time. 
 
 PASSAGES OF THE CENTRAL AND LATERAL VORTICES, OBSERVED IN JUNE 
 AND JULY, 1853, IN LATITUDE 41 20' NORTH. 
 
 I signify ing inner ; O, outer ; C, central ; A, ascending ; D, descending. 
 
 Order. 
 
 Vortex. 
 
 Date. 
 
 Meridian 
 Passage. 
 
 Passage. 
 
 Calculated latitude and 
 Remarks. 
 
 1st 
 
 LA. 
 
 June 2 2 
 
 7 A. M. 
 
 south 
 
 Centre. About 40. 
 
 
 
 23 
 
 8 A. M. 
 
 north 
 
 Warsaw. Storm. 
 
 2d 
 
 O.D. 
 
 27 
 
 Omoon 
 
 north 
 
 
 
 
 28 
 
 1 A. M. 
 
 south 
 
 See record. 
 
 3d 
 
 C.A. 
 
 July 1 
 
 9 A. M. 
 
 south 
 
 
 
 
 2 
 
 10 A. M. 
 
 north 
 
 Lat. 43. Storm. 
 
 4th 
 
 I. D. 
 
 7 
 
 5 P. M. 
 
 north 
 
 
 
 
 8 
 
 6 P. M. 
 
 south 
 
 Lat. New York. Storm. 
 
 5th 
 
 C.D. 
 
 12 
 
 5P.M. 
 
 north 
 
 Aurora. 
 
 
 
 13 
 
 6 P. M. 
 
 south 
 
 Stormy, very. 
 
 6th 
 
 O.A. 
 
 14 
 
 10 A. M. 
 
 south 
 
 
 
 
 15 
 
 11 A. M. 
 
 north 
 
 See Record. 
 
 The intervals between the ascending and descending passages 
 of the different vortices, are 
 
 Between I. A. and I. D. from 11 to 14 days. 
 " O.A. " O.D. " 10 " 12 " 
 " C.A. " C. D. " 9 " 11 " 
 and the effect is greatest when the vortex comes to the meridian 
 
MECHANICAL THEORY OF STOEMS. 87 
 
 before the sun, and least when after the sun ; in which case 
 the full effect is not developed, sometimes until the following 
 day. 
 
 A brief abstract from a journal of the weather for one sidereal 
 period of the moon, in 1853. 
 
 June 21st. Fine clear morning (S. fresh) :* noon very warm 
 88 ; 4 P. M. plumous cirri in south ; ends clear. 
 
 22d. Haz}' morning (S. very fresh) arch of cirrus in west ; 
 2 P. M., black in W.-N.-W. ; 3 P. M., overcast and rainy ; 4 P. M., 
 a heavy gust from south ; 4.30 p. M., blowing furiously (S. by 
 W.) ; 5 P. M., tremendous squall, uprooting trees and scattering 
 chimneys ; 6 p. M., more moderate (W.) 
 
 23d. Clearing up (N.-W.) ; 8 A. M., quite clear; 11 A.M., 
 bands of mottled cirri pointing IsT.-E. and S.-W. ; ends cold 
 (W.-N.-W.) ; the cirri seem to rotate from left to right, or with 
 the sun. 
 
 24th. Fine clear cool day, begins and ends (N.-W.) 
 
 25th. Clear morning (N.-W. light) ; 2 p. M., (E.) calm ; tufts 
 of tangled cirri in north intermixed with radiating streaks, all 
 passing eastward ; ends clear. 
 
 26th. Hazy morning (S.-E.) cloudy; noon, a heavy windy 
 looking bank in north (S. fresh), with dense cirrus fringe above 
 on its upper edge ; clear in S. 
 
 2 7th. Clear, warm, (W.) ; bank in north ; noon bank covered 
 all the northern sky, and fresh breeze; 10 P. M., a few flashes 
 to the northward. 
 
 28th. Uniform dense cirro-stratus, (S. fresh) ; noon showers 
 all round ; 2 P. M., a heavy squall of wind, with thunder and 
 rain (S.-W. to N.-W.) ; 8 P. M., a line of heavy cumuli in south ; 
 8.30 P. M., a very bright and high cumulus in S.-W., protruding 
 through a layer of dark stratus ; 8.50 P. M., the cloud bearing E. 
 by S., with three rays of electric light, f 
 
 * K. B. The letters in a parenthesis signify the direction of the wind. 
 t Giving this cloud the average velocity of thirty miles per hour, its 
 
88 
 
 MECHANICAL THEORY OF STORMS. 
 
 R.11 
 
 June 29th. A stationary stratus over all, (S.-W. light) ; clear 
 at night, but distant lightning in S. 
 
 30th. Stratus clouds (N.-E. almost calm) ; 8 A. M., raining 
 gently ; 3 P. M., stratus passing off to S ; 8 P. M., clear, pleas- 
 ant. 
 
 July 1st. Fine and clear; 8 A. M., cirrus in sheets, curls, 
 wisps, and gauzy wreathes, with patches beneath of darker shade, 
 
 altitude was determined by the sextant at twelve miles, and we think 
 under- estimated. "While measuring, the author's attention was drawn 
 to the fact, that although it appeared equally dense above and below, 
 yet its middle part was the brightest, and as there was only a faint glim- 
 mer of twilight in the N.-W., he concluded that the cloud was self-lumin- 
 ous ; for when the smallest stars were visible, it glowed about as bright 
 as the milky-way in Sagittarius. Occasionally the whole cloud was lit 
 up internally by the lightning, and about this time it sent off three rays : 
 one horizontally, westward, which was the faintest ; one about N.-W., 
 towards Jupiter, and the brightest of the three ; and another towards 
 the north. These were not cirrus streaks, but veritable streams of elec- 
 tric matter, and had a very decided rotation from left to right, and con- 
 tinued visible about twenty minutes, as represented above.. 
 
MECHANICAL THEORY OF STORMS. 89 
 
 all nearly motionless; close and warm (N.-E.); a long, low 
 bank of haze in S., with one large cumulus in S.-W., but very 
 distant. 
 
 July 2d. At 5 A. M., overcast generally with hazy clouds and 
 fog of prismatic shades, chiefly greenish-yellow ; 7 A. M., (S.-S.- 
 E. freshening,) think in W; 8 A. M., (S. fresh) much cirrus, 
 thick and gloomy ; 9 A. M., a clap of thunder, and clouds hur- 
 rying to N. ; a reddish haze all around ; at noon the margin of 
 a line of yellowish-red cumuli just visible above a gloomy-look- 
 ing bank of haze in N.-N.-W., (S. very fresh ;) warm, 86 ; more 
 cumuli in N.-W. the whole line of cumuli 1ST. are separated 
 from the clouds south by a clear space. These clouds are borne 
 rapidly past the zenith, but never get into the clear space they 
 seem to melt or to be turned off N.-E. The cumuli in N. and 
 N.-W., slowly spreading E. and S. ; 3 P. M., the bank hidden 
 by small cumuli ; 4 p. M., very thick in north, magnificent 
 cumuli visible sometimes through the breaks, and beyond them 
 a dark, watery back-ground, (S. strong); 4.30 p. M., wind round 
 to N.-W. in a severe squall ; 5 P. M., heavy rain, with thunder, 
 &c. all this time there is a bright sky in the south visible 
 through the rain 15 high ;, 7 P. M., clearing, (S.-W. mod.) 
 
 July 3d. Very fine and clear, (N.-W.) ; noon, a line of large 
 cumuli in N., and dark lines of stratus below, the cumuli mov- 
 ing eastward; 6 P. M., their altitude 2 40'. Velocity 1 per 
 minute ; 9 P. M., much lightning in the bank north.* 
 
 July 4th. 6 A. M., a line of small cumulo-stratus, extending 
 
 * This day the central vortex passed in about latitude 47 N. the 
 southern margin cannot be nearer than 250 miles, throwing off the 40' 
 for the horizontal refraction, would give eight miles of altitude above a 
 tangential plane. Then another seven miles, for curvature, will give an 
 altitude of fifteen miles for the cumuli. The height of these thunder- 
 clouds has been much under-estimated. They seem to rise in unbroken 
 folds to a height of ten and twelve miles frequently ; from the data 
 afforded by the theory, we believe they will be found much higher some- 
 times even as much as sixteen miles. 
 
90 MECHANICAL THEORY OF STORMS. 
 
 east and west, with a clear horizon north and south 10 high. 
 This band* seems to have been thrown off by the central yes- 
 terday, as it moves slowly south, preserving its parallelism, al- 
 though the clouds composing it move eastward. Fine and cool 
 all day (N.-W. mod.) Lightning in N. 
 
 July 5th. Cloudy (N. almost calm), thick in E., clear in W. ; 
 same all day. 
 
 6th. Fine and clear (E. light) ; small cumuli at noon ; clear 
 night. 
 
 7th. Warm (S. E. light) ; cirrus bank N. W. ; noon (S.) 
 thickening in N. ; 6 p. M., hazy but fine ; 8 P. M., lightning in 
 N. ; 10 P. M., the lightning shows a heavy line of cumuli along 
 the northern horizon ; calm and very dark and incessant light- 
 ning in N". 
 
 8th. Last night after midnight commencing raining, slowly 
 and steadily, but leaving a line of lighter sky south ; much 
 lightning all night, but little thunder. 
 
 8th. 6 A. M. Very low scud (500 feet high) driving south, still 
 calm below, (N. light) ; 10 A. M., clearing a little; a bank north 
 with cirrus spreading south ; same all day ; 9 P. M., wind 
 freshening (N. stormy) ; heavy cumuli visible in S. ; 10.30 p. M., 
 quite clear, but a dense watery haze obscuring the stars; 12 
 p. M., again overcast : much lightning in S. and N.-W. 
 
 * These parallel bands, and bands lying east and west, are frequent 
 in fine weather between two vortices. Sailors consider them a sign of 
 settled weather. After dark there was frequently seen along the north- 
 ern horizon flashes of lightning in a perfectly clear sky. But they were 
 both faint and low, not reaching more than 4 or 5 above the horizon. 
 After sunset there were very distinct rays proceeding from the sun, but 
 they were shorter than on the evening of the 3d. These are caused by 
 the tops of the great cumuli of the storm, when sunk below the horizon, 
 intercepting the sun's rays, which still shine on the upper atmosphere. 
 The gradation was very marked, and accorded with the different dis- 
 tances of the central vortex on the 3d and 4th although, on the 4th, the 
 nearest distance must have been over four hundred miles to the south- 
 ern boundary of the storm. 
 
MECHANICAL THEOBY OF STORMS. 91 
 
 9th. Last night (2 A. M. of 9th) squall from N.-W. very 
 black ; 4 A. M., still raining and blowing hard, the sky a perfect 
 blaze, but very few flashes reach the ground ; 7 A. M., raining 
 hard ; 8 A. M. (N.-W. strong) ; a constant roll of thunder ; 
 noon (N.-E.) ; 2 p. M. (N.) ; 4 p. M. clearing ; 8 P. M., a line 
 of heavy cumuli in S., but clear in N.-W., N., and N.-E.* 
 
 NEW YORK STORM, JULY 8, 1853. 
 
 " At 5 o'clock Friday afternoon, a terrible storm of rain, hail, 
 and lightning, rose suddenly from the north-west, and passed 
 over the upper part of the city and neighborhood. It was quite 
 moderate in the lower part of the town, and probably scarcely 
 felt on Staten Island. The whole affair lasted not more than a 
 quarter of an hour, yet the results were most disastrous, as will 
 be seen by the following accounts from our reporters : 
 
 " Happening to be in the neighborhood of the Palace about 
 5 o'clock Friday evening, we sought shelter under its ample 
 roof from an impending thunder storm, of very threatening 
 appearance, rapidly approaching from the west. We had 
 scarcely passed the northern entrance, and reached the gallery 
 by the nearest flight of steps, when the torrent it was not rain, 
 but an avalanche of water struck the building ; the gutters 
 were filled on the windward side in a moment, and poured over 
 
 * It is worthy of notice here, that New York, which only differs by 
 about 40 miles of latitude and 800 in longitude, had the storm earlier, 
 near the time of the passage, as appears by the appended account of it. 
 This proves, that a storm affects a particular latitude simultaneously, or 
 approximately so. If this had to travel eastward to reach New York, 
 it would have been the 10th instead of the 8th. The principal trouble 
 was, however, in the early part of the evening of the 8th, to the south 
 of Ottawa, where the strong wind was drawn in from the northward. 
 If a vortex passes from north to south, leaving the observer between the 
 passages, there must, nearly always, be a winding up squall from the 
 north to clear away the vapory atmosphere. 
 
92 MECHANICAL THEOKY OF STORMS. 
 
 an almost unbroken sheet of water, which was driven through 
 'the Venetian blind ventilators, into and half way across the 
 north-west gallery, and also through the upper ventilators, fall- 
 ing upon the main floor of the north transept. Workmen 
 hastened to close the blinds, but that did not prevent the deluge. 
 The tinning of the dome being unfinished, the water, of course, 
 came down in showers all over the centre. Many workmen 
 were engaged on the dome when the shower struck it ; several 
 of them, in their haste to escape such dangerous proximity to 
 the terrific lightning, came down single ropes, hand over hand. 
 Large number of workmen were engaged all over the exterior, 
 and such a scampering will rarely be witnessed but once in a 
 lifetime. It was found impossible to close a north window, 
 used for ingress and egress of workmen upon the roof, and the 
 water came in, in almost solid columns. For a time the water 
 was nearly two inches deep on the gallery floor, and .poured 
 down the stairs in miniature cascades. 
 
 " A great number of boxes, bales, and packages of goods lay 
 upon the main floor, among which the water poured down from 
 the edge of the gallery floor in destructive quantities. For- 
 tunately but few goods were opened, and were upon the tables, 
 or the damage would have been irreparable. As it is, we fear 
 some of the goods are injured. In the height of the storm, the 
 centre portion of the fanlight over the western entrance burst in, 
 and several single lights were broken, by staging or otherwise. 
 
 " About ten minutes after the storm burst, the most terrific 
 hailstorm we ever saw began to rattle, like discharges of mus- 
 ketry, upon the tin roof and glass sides. Some of the masses of 
 ice were as large as hen's eggs. There were probably a thou- 
 sand excited workmen in the building, and a good many ex- 
 hibitors and visitors, among whom there were some twenty 
 ladies, some of whom appeared a good deal alarmed at the 
 awful din. A portion of the frame-work of the addition next to 
 42d street, went down with a terrible crash, and a part of the 
 
MECHANICAL THEORY OF STORMS. 93 
 
 brick wall of the engine-house on the opposite side of the street, 
 was blown over, crushing two or three shanties, fortunately with- 
 out any other injury than driving the occupants out into the 
 storm. But an awful scene occurred on the north side of 43d 
 street, directly opposite the Latting Tower. Here two large un- 
 finished frame buildings were blown, or rather, we should judge 
 from appearances, were crushed down into a mass of ruins, such 
 as may be imagined by supposing a great weight had fallen, 
 with a circular, grinding motion, upon the first fine fabrics. 
 One of them was partly sided, and had the rafters up, but no 
 roof; the other was sided and roofed with tin, and was being 
 plastered. We were told it was three stories high, 50 by 98 
 feet. 
 
 " We reached the ruins among the first, after the burst of the 
 storm subsided a little. The scene was such as we pray God 
 we may never witness again. A small portion of the roof and 
 upper part of the front of the building stood or rather partly 
 hung over the side-walk. The chamber and lower floor of the 
 front rooms lay flat together. The sides were standing. In the rear 
 all were down. In this building, besides the workmen, there 
 were numerous laborers who had taken shelter under its roof 
 when the storm drove them hurriedly from their work. How 
 so many persons escaped death is truly wonderful. It can only 
 be accounted for by supposing that they had a moment's warn- 
 ing, and rushed into the street. The first alarm was from the 
 tearing off a portion of the tin roof, which was carried high over 
 another building, and fell in the street. A horse and cart barely 
 escaped being buried under this. It seems the frame of the 
 other building came down with a deafening crash at the same 
 time, confusing instead of warning those in danger. At any 
 rate, before they could escape, they were buried in a mass of 
 timber, and three of them instantly killed, and four or five 
 dangerously wounded ; and others slightly bruised and badly 
 frightened. Several would have perished but for timely assist- 
 
94 MECHANICAL THEOEY OF STOEMS. 
 
 ance to extricate them. In this they were greatly assisted by 
 Jacob Steinant, boss carpenter of the Tower, who with his men 
 rushed to the rescue, notwithstanding the pouring down tor- 
 rents. 
 
 " In Williamsburgh, the storm lasted about fifteen minutes, 
 doing an incalculable amount of damage to dwellings, foliage, 
 &c. Hailstones came down in sizes from that of a hickory-nut 
 to a large apple, some with such force as to drive them through 
 the cloth awnings. 
 
 " The storm passed over Brooklyn lightly, in comparison with 
 the effects across the Williamsburgh line. On Flushing avenue, 
 beyond the Naval Hospital, a number of trees were uprooted, 
 and the window-panes of the houses shattered. On the corner 
 of Fulton and Portland avenues, three building were unroofed, 
 and the walls of the houses were sprung to the foundation. 
 
 " On Spencer street, a new frame building was levelled with 
 the ground. Along Myrtle, Classon, and other streets and 
 avenues of East Brooklyn, many of the shade trees were up- 
 rooted, and the windows smashed. In Jay street, two trees 
 were struck by lightning, but no other damage ensued. 
 
 " Several schooners at the foot of Jay street were forced from 
 their moorings, but were soon after secured. A small frame 
 house in Spencer street, just put under roof, was prostrated to 
 the ground. 
 
 " We understand that a large barn filled with hay, situated 
 on the road between Bushwick and Flushing, was struck by 
 lightning and destroyed with its contents, embracing several 
 head of live stock."* 
 
 July 10th, 3 A. M. Overcast and much lightning in south (N. 
 mod.) ; 7 A. M., clear except in south ; 6 p. M. (E.) ; 10 p. M., 
 lightning south; 11 p. M., auroral rays long but faint, converg- 
 ing to a point between Epsilon Virginis and Denebola, in west ; 
 low down in west thick with haze; on the north the rays con- 
 * From the New York Tribune, July 9, 1853. 
 
MECHANICAL THEORY OF STOEMS. 95 
 
 verged to a point still lower ; lightning still visible in south. 
 This is an aurora in the west. 
 
 llth. Fine clear morning (N.-E.) ; same all day; no light- 
 ning visible to-night, but a bank of clouds low down in south, 
 2 high, and streaks of dark stratus below the upper margin. 
 
 12th. Fine and clear (N.-E.) ; noon, a well defined arch in 
 S.-W., rising slowly ; the bank yellowish, with prismatic shades 
 of greenish yellow on its borders. This is the 0. A. At 6 P. M., 
 the bank spreading to the northward. At 9 P. M., thick bank 
 of haze in north, with bright auroral margin ; one heavy pyra- 
 mid of light passed through Cassiopcea, travelling westward 
 H per minute. This moves to the other side of the pole, but 
 not more inclined towards it than is due to prospective, if the 
 shaft is very long; 11.10 P. M., saw a mass of light more 
 diffuse due east, reaching to Markab, then on the prime 
 vertical. It appears evident this is seen in profile, as it inclines 
 downwards at an angle of 10 or 12 from the perpendicular. 
 It does not seem very distant. 12 P. M., the aurora still bright, 
 but the brightest part is now west of the pole, before it was east. 
 
 13th, 6 A. M. Clear, east and north; bank of cirrus inNVW., 
 i. e., from N.-N.-E. to W. by S. ; irregular branches of cirrus 
 clouds, reaching almost to south-eastern horizon ; wind changed 
 (S.-E. fresh) ; 8 A, M., the sky a perfect picture ; heavy regular 
 shafts of dense cirrus radiating all around, and diverging from 
 a thick nucleus in north-west, the spaces between being of clear 
 blue sky. The shafts are rotating from north to south, the 
 nucleus advancing eastward. 
 
 Appearance of the central vortex descending at 8 A. M., July 
 13th, 1853 : 
 
 In Fig. 1 8, the circle represents the whole sky from the zenith 
 to the horizon, yet it can convey but a very faint idea of the regu- 
 larity and vividness of this display. The reflected image of the 
 sky was received from a vessel of turbid water, which will be 
 found better than a mirror, when the wind will permit. 
 
96 
 
 MECHANICAL THEOKY OF STOEMS. 
 
 At noon (same day) getting thicker (S.-E. very fresh) ; 6 p. M., 
 moon on meridian, a prismatic gloom in south, and very 
 thick stratus of all shades ; 9 P. M., very gloomy ; wind 
 stronger (S.-E.) ; 10 p. M, very black in south, and overcast 
 generally. 
 
 14th. Last night about 12 p. M. commenced raining; 3 A. M., 
 rained steadily ; 7 A. M , same weather ; 8.20 A. M., a line of low 
 storm-cloud, or scud, showing very sharp and white on the 
 dark back ground all along the southern sky. This line con- 
 tinues until noon about 10 at the highest, showing the north- 
 ern boundary of the storm to the southward ; 8 p. M., same 
 bank visible, although in rapid motion eastward ; same time 
 
MECHANICAL THEORY OF STORMS. 97 
 
 clear overhead, with cirrus fringe pointing north from the bank ; 
 much lightning in south (W. fresh) ; so ends. 
 
 15th. Last night a black squall from N.-W. passed south 
 without rain ; at 3 A. M. clear above, but very black in south 
 (calm below all the time) ; 9 A. M., the bank in south again 
 throwing off rays of cirri in a well-defined arch, whose vortex 
 is south : these pass east, but continue to form and preserve 
 their linear direction to the north ; no lightning in south to- 
 night. 
 
 16th. Clear all day, without a stain, and calm. 
 
 17th. Fine and clear (N.-E. light) ; 6 p. M., calm. 
 
 18th. Fair and cloudy (N.-E. light) ; G P. M., calm. 
 
 19th. Fine and clear (N. fresh) ; I. V. visible in S.-W. 
 
 20th. 8 A. M., bank in N.-W. with beautiful cirrus radiations; 
 10 A. M., getting thick with dense plates of cream-colored cirrus 
 visible through the breaks ; gloomy looking all day (N.-E. 
 light).* 
 
 Appearance of the Inner Vertex at 8 A. M., July 20th, 1853, 
 including the whole sky. (See Fig. 19.) 
 
 This was a different passage of the Inner Vortex ascending 
 as compared with the same 28 days before. At that date (June 
 22) it did great damage in the central parts of Illinois. Still 
 this last passage was very palpable the clouds were very irreg- 
 ularly assorted plates of cirrus above and beneath cumulus 
 various kinds of cirrus clouds, and that peculiar prismatic haze 
 
 * These pages are now in the compositors' hands, (Nov. 21st,) and up 
 to the last moment the author has observed carefully in New York the 
 passages of these vortices. October 24th, the inner vortex descending 
 produced a violent storm on the coast, and much damage ensued. No- 
 vember 7th, the same vortex ascending was also severe. And on 
 November 13th, early, the passage of the central vortex ascending, caused 
 a flood in Connecticut of a very disastrous nature. Would it not pay 
 the insurance offices to patronize such investigations in view of such 
 palpable facts as these ? 
 
 5 
 
98 
 
 MECHANICAL THEOEY OF STOEMS. 
 
 Fia.19 
 
 
 which is a common sign of the passage of a vortex. The ap- 
 pearance depicted above is a very common, although a very 
 evanescent appearance. When the sky appears of a clear blue 
 through the cirri, there will be generally fresh gales without any 
 great electrical derangement ; but if the clear spaces are hazy, 
 gradually thickening towards the nucleus, a storm may be ex- 
 pected. Any one who wishes to understand the indications of 
 the clouds, must watch them closely for many years, before he 
 can place much reliance upon them. But we shall again advert 
 to this point. 
 
 We have now passed through one sidereal period of the 
 moon. We might continue the record, but it would be tedious. 
 
MECHANICAL THEORY OF STORMS. 99 
 
 The passages of these vortices vary in violence at different times, 
 as we might expect ; but they never cease to circulate, and 
 never will as long as the moon remains a satellite to the earth ; 
 and if we take the passage of any of these vortices, and add 
 thereto the time of one sidereal period of the moon, we get ap- 
 proximately the time of the next passage. When the elements 
 of the lunar orbit tend to accelerate the passages, they may 
 come in 26 days ; and when to retard, in 28 days; and these 
 are about the limits of the theory. 
 
 Having begun and ended this record of the weather with the 
 passage of the Inner vortex ascending, it may not be amiss to no- 
 tice one more, (the August passage,) as it offers a peculiarity not 
 often so distinctly marked. We have alluded to the greater 
 force of the storms when the passage of the vortex corresponds 
 to the passage of the line of low barometer or the depression 
 point of a great atmospheric wave, which is also due to the ac- 
 tion of the ether. In consequence of these waves passing from 
 west to east, the storm will only be violent when formed a 
 little to the westward. If the storm forms to the eastward, we 
 neither see it nor feel it, as it requires time to develop its 
 strength, and always in this latitude travels eastward ; so that 
 storms may generally be said to come from the west, although 
 the exciting cause travels from east to west. In the case now 
 alluded to, the weather indicated a high barometer, and the 
 storm formed immediately to the eastward, even showing a dis- 
 tinct circular outline. We subjoin a description. 
 
 August 15th. Clear morning (N.-E.), a bank of cumuli in 
 south : noon quite cloudy in S. and clear in north. (N.-E.) 
 
 l^th. Clear morning (N.-E.) ; 3 p. M., getting very black in 
 E. and S.-E., very clear to the westward ; 4 p. M., much thun- 
 der and lightning in east, and evidently raining hard ; 5 P. M., 
 a violent squall from east for 10 minutes ; tore up several 
 trees ; 6 P. M., the storm passing eastward, clear in west all 
 this time ; 6.30 P. M., the storm forming a regular arch, the 
 
100 MECHANICAL THEOEY OF STOEMS. 
 
 vertex being in S.-E. ; 8 P. M., the arch of hazy cirrus and 
 heavy cumulus much lower in S.-E., wind still moderate from 
 east ; 10 P. M., clear all around, but lightning in S.-E. and E. 
 
 17th. Fine clear morning (W.) ; noon, scattered cumuli in 
 north ; 6 P. M., a beautifully regular arch of dense cumuli and 
 cirrus margin in N.-E., with a constant glimmer of lightning ; 
 7 P. M., very clear to the west, and north-west, and south ; 
 along the northern horizon a line of high peaked cumuli ter- 
 minating in N.-N.-W. ; a continued roll of distant thunder in 
 the circular bank in N.-E,, and not a moment's cessation to the 
 lightning ; the electric excitement advancing westward along 
 the lines of cumuli ; the cirrus haze also rising and passing to- 
 wards S.-W. ; 8 P. M., the sky alive with lightning, the cirrus 
 now reaches the zenith ; no streaks of lightning coming to the 
 earth ; they seem to radiate from the heaviest mass of cumuli, 
 and spread slowly (sufficiently so to follow them) in innumer- 
 able fibres over the cloudy cirrus portion of the sky ; every 
 flash seems to originate in the same cloud ; 8.30 p. M., one 
 branching flash covered the whole north-eastern half of the 
 sky, no leafless tree of the forest could show so many branches ; 
 9.30 P. M., all passed to S.-W. without rain, leaving behind a 
 large cumulus, as if it lagged behind. From this cumulus a 
 straight line of lightning shot up 10 above the cloud into a 
 perfectly clear sky, and terminated abruptly without branching. 
 
 We have been thus particular in giving these details, as this 
 was a clear case confirming the principles advanced, that the 
 vortices do not form a continuous line of disturbance, in their 
 daily passage around the earth. It shows also that the barom- 
 eter, in connection with these principles, will be a far more use- 
 ful instrument than it has yet proved itself, for practical service 
 as an indicator of the weather. 
 
SECTION THIRD. 
 
 OBJECTIONS TO LUNAR INFLUENCE. 
 
 WE have now presented a theory of the weather, which 
 accounts for many prominent phenomena, a few of which we 
 shall enumerate. It is an observed fact, that in all great storms 
 electrical action is more or less violent, and that without this 
 element it seems impossible to explain the velocity of the wind 
 in the tornado, its limited track, and the formation of large 
 masses of ice or hail in the upper regions of the atmosphere. 
 It is also an observed fact, that the barometer is in continued 
 motion, which can only be legitimately referred to a change in 
 the weight of the atmospheric column. This we have explained 
 as due to atmospheric waves, caused by the greater velocity of 
 rotation of the external ether, as well as to the action of the 
 three great vortices. These causes, however, only partially 
 produce the effect the greater portion of the daily oscillations 
 is produced by the action of the great radial stream of the solar 
 vortex, as we shall presently explain. It is an observed fact, that, 
 although the storm is frequently violent, according to the de- 
 pression of the barometer, it is not always so. According, to 
 the theory, the storm will be violent, ceteris paribus, on a line 
 of low barometer, but may still be violent, when the contrary 
 obtains. Another fact in the disturbance of the magnetic needle 
 during a storm. Storms are also preceded generally by a rise in 
 the thermometer, and succeeded by a fall ; also by a fall in the 
 
102 MECHANICAL THEORY OF STOEMS. 
 
 barometeiy and' succededc by'< a' rise.* l It is also well known, that 
 hurricanes are unknown at the equator, and probably at the 
 poles also. At all events, they are rare in lat. 80, and, accord- 
 ing to Capt. Scoresby, storms are there frequently raging to the 
 south, while above, there is clear sky and fine weather, with a 
 stiff breeze from the northward. The greater violence of storms 
 in those regions where the magnetic intensity is greater in the 
 same latitude, the probable connection of peculiarities in the 
 electric state of the atmosphere with earthquakes, and the indi- 
 cations of the latter afforded by the magnet ; the preponderance of 
 westerly winds at a great elevation in every latitude on the globe 
 visited by man ; and the frequent superposition of warm layers of 
 air above cold ones at those elevations, are all facts worthy of note. 
 And the connection of cirrus clouds with storms, as well as 
 with the aurora, indicates that the producing cause is external 
 to the atmosphere, and gradually penetrates below. The theory 
 fully explains this, and is confirmed by the fantastic wreathings 
 and rapid formation of these clouds in straight lines of a 
 hundred miles and upwards. But time would fail us in point- 
 ing out a tithe of the phenomena, traceable to the same cause, 
 which keeps our atmosphere in a perpetual state of change, and 
 we shall only advert to one more peculiarity of the theory. It 
 places meteorology on a mathematical basis, and explains why 
 it is that a storm may be raging at one place, while in another, 
 not very remote, the weather may be fine, and yet be depend- 
 ent on the position of the moon. 
 
 That the moon has exerted an influence on the weather has 
 been the popular creed from time immemorial ; but, ignorant 
 of the mode in which this influence was exerted, men have 
 often been found who have fostered the popular belief for their 
 own vanity or advantage ; and, on the other hand, philosophers 
 have assailed it more by ridicule than by argument, as a relic 
 of a barbarian age. Not so with all ; for we believe we are 
 not wrong in stating, that the celebrated Olbers compared the 
 
MECHANICAL THEOKY OF STOEMS. 103 
 
 moon's positions with the weather for fifty years, before he gave 
 his verdict against it. He found the average amount of rain 
 at the perigee about equal to the amount at the apogee, as 
 much at the full as at the change, and no difference at the 
 quadratures. But this fact does not throw a feather in the 
 scale by which this theory is weighed. Popular opinions, of 
 remote origin, have almost always some foundation in fact, and 
 it is not much more wise to reject them, than to receive them. 
 The Baron Von Humboldt a man possessing that rare ingre- 
 dient of learning, a practical common sense observes : ." That 
 arrogant spirit of incredulity which rejects facts, without at- 
 tempting to investigate them, is, in some cases, more injurious 
 than an unquestioning credulity."* If a popular belief or 
 prejudice be absurd, its traditional preservation for a thousand 
 years or more may very well account for the absurdity. 
 
 The present system of astronomy still retains the motley 
 garniture of the celestial sphere, as handed down from the most 
 remote antiquity; and granting that ages of ignorance and 
 superstition have involved the history of the different constella- 
 tions in a chaos of contradictory traditions, there is no doubt 
 at the foundation some seeds of truth which may even yet 
 emerge from the rubbish of fable, and bear fruit most 
 precious. That the zodialf signs are significant records of 
 something worthy of being preserved, is prejudice to deny; and 
 we must be allowed to regard the Gorgons and Hydras of the 
 skies as interesting problems yet unsolved, as well as to consider 
 that the belief in lunar influence is a fragment of a true system 
 of natural philosophy which has become more and more 
 debased in postdiluvian times. Amongst those who have not 
 summarily ignored the influence of the moon, is Toaldo, a 
 Spanish physicist, who endeavored to show the connection 
 
 * Hum. Cosmos, art. Aerolites. 
 
 f We shall in all eases use this abbreviation for the extremely awk- 
 ward word zodiacal. 
 
104 MECHANICAL THEOKY OF STOKMS. 
 
 between the recurrence of warm and cold seasons, and the 
 semi-revolution of the lunar nodes and apogee, and proposed 
 six of those periods, or about fifty-four years, as the cycle in 
 which the changes of the weather would run through their 
 course. According to the present theory, it is not likely such 
 a cycle will ever be discovered. There are too many secular, 
 as well as periodic influences combining, to produce the effect ; 
 and the times are too incommensurable. Lately, Mr. Glaisher 
 has presented a paper to the Royal Society, giving about four- 
 teen years from observation. Others have lately attempted to 
 connect the changes of the seasons with the solar spots, as well 
 as with the variations of the magnetism of the earth, but with- 
 out any marked result. 
 
 It may, however, be urged, that if the sidereal period of the 
 moon be approximately a cycle of change, it would have been 
 detected long ago. One reason why this has been so long con- 
 cealed, is the high latitude of the observers. Spain, Italy, and 
 Turkey, are better situated than other European countries ; but 
 the scientific nations lie further north ; and from these the law 
 has gone forth to regulate more southern lands. In the United 
 States, particularly in the great plains of the west, the weather 
 can be better compared ; not only on account of the latitude 
 being more favorable, but also on account of the greater mag- 
 netic intensity of the western hemisphere. 
 
 It must also be remembered that there are in latitude 40, 
 five or six distinct passages of the disturbing cause in one 
 sidereal period of the moon. If two of these periods are drawn 
 closer together by the change of the elements, the interval be- 
 tween two others must necessarily be increased. Besides, the 
 effect produced is not always the same, for reasons already ad- 
 verted to. One vortex may be more violent one month, or for 
 a few days in one month, while another may be more active the 
 next. It may also happen that for several successive passages, 
 the passage shall be central in one latitude, while two or three 
 
MECHANICAL THEOKY OF STOEMS. 105 
 
 degrees north or south, another place shall be passed by. In 
 different months and in different years, as well as in different 
 seasons of the year, the energy of the ether may be augmented 
 or diminished. But it may be said, that, supposing the theory 
 true, if its indications are so uncertain, it is of little value. By 
 no means. It is true there are many things to be inquired 
 into ; but it is a great thing in this science to be able to take 
 the first step in the right direction, to find even the key of the 
 portal. It is a great stride to be able to say, a storm may hap- 
 pen at such a time, but cannot happen at another ; that a storm, 
 when raging, will go in this direction, rather than in that ; that 
 it will be central here, and less violent yonder ; and when we 
 consider its bearing on astronomical, and other science, it is diffi- 
 cult to exaggerate its value to the world at large. 
 
 Again, it may be said that rain, and cloudy days, and fresh 
 breezes, and even strong winds, sometimes occur, when the vor- 
 tices do not pass centrally. This is true ; yet only indicating 
 that where the vortices are central, an unusual disturbance is 
 taking place. But there is another cause, which was purposely 
 omitted in considering the prominent features of the theory, in 
 order not to encumber the question with secondary influences. 
 By referring to Fig. 3, section 1, we see that the lateral vor- 
 tices of the globe are continually passing off to the southward, 
 in the northern hemisphere, in a succession of dimples, and con- 
 tinually reforming. We will now represent this mode of action 
 in profile, as it actually occurs in the illustration we have used. 
 
 The vortex passing off from O, (Fig. 20,) although it does not 
 actually reach the surface of the atmosphere, affects the equilib- 
 rium of the ether, and, for a short distance from the parent vortex, 
 may cause an ascensional movement of the air. If to this is con- 
 joined a northerly wind from the vortex, a band of clouds will 
 be produced, and perhaps rain ; but violent storms never occur 
 in the intervals, except as a steady gale, caused by the violence 
 of a distant storm. Thus, it will frequently be noticed that 
 
 5* 
 
106 MECHANICAL THEORY OF STOEMS. 
 
 Fig. 20 
 
 Pol* 
 
 these vortices are flanked by bands of clouds, which pass south- 
 ward, although the individual clouds may be moving eastward. 
 Hence, instead of disproving the theory, they offer strong evi- 
 dence of its truth ; and could we view the earth from the moon 
 with a telescope, we should no doubt see her beautifully belted. 
 But it may be again asked, why should not the weather be 
 the same generally, in the same latitude, if this theory be true ? 
 If the earth were a globe of level land, or altogether of water, 
 no doubt it would be similar ; but it must be remembered, that 
 both land and water are very unequally distributed ; that the 
 land is of varying extent and elevation here a vast plain, far 
 removed from the ocean, and there a mountain chain, interposing 
 a barrier to the free course of the atmospheric currents ; some- 
 times penetrating in full width into the frigid zone, and again 
 dwindling to a few miles under the equator. One very import- 
 ant distinction is also to be remarked, in the superficial area of 
 the different zones, reckoning from the equator, and taking the 
 hemisphere as 100 parts : 
 
 Frigid zone 8 parts. 
 
 Temperate " 52 " 
 
 Torrid " . 40 " 
 
MECHANICAL THEORY OF STORMS. 107 
 
 For as the time of rotation in every latitude is the same, the 
 area to be disturbed in the same time, is less in high latitudes, 
 and there a greater similarity will obtain, ceteris paribus. In 
 lower latitudes, where both land and water stretch away for 
 thousands of miles, it is not wonderful that great differences 
 should exist in the electrical and hygrometric state of the air. 
 
 The summer of many countries is always dry California 
 for instance. In winter, in the same country, the rains are ap- 
 parently incessant. This of course depends on the power of the 
 sun, in diverting the great annual currents of the atmosphere. 
 As long as the dry north-west trade sets down the coast of 
 California, the circumstances are not favorable for giving full 
 development to the action of the vortices. When the trade 
 wind ceases, and the prevailing winds come from the south, 
 loaded with vapor, the vortices produce storms of any magni- 
 tude ; but (and we speak from two years' observation) the pas- 
 sages of the vortices are as distinctly marked there in winter 
 time, as they are in the eastern States ; and in summer time, 
 also, they are very perceptible. The same remark applies to 
 Mediterranean countries, particularly to Syria and Asia Minor ; 
 although the author's opportunity for observing lasted only from 
 April to December, during one season. If we are told it never 
 rains on the coast of Peru, or in Upper Egypt, it does not se- 
 riously militate against the theory. The cause is local, and the 
 Samiel and the sand storm of the desert, is but another phase 
 of the question, explicable on the same general principles. 
 From the preceding remarks it will be seen, that in order to 
 foretell the character of particular days, a previous knowledge 
 of the weather at that particular place, and for some consider- 
 able time, is requisite ; and hence the difficulty of laying down 
 general rules, until the theory is more fully understood. 
 
108 MECHANICAL THEOEY OF STORMS. 
 
 MODIFYING CAUSES. 
 
 We now come to the causes which are auxiliary and inter- 
 fering. It is natural that we should regard the sun as the first 
 and most influential of these causes, as being the source of that 
 variation in the temperature of the globe, which alternately 
 clothes the colder regions in snow and verdure. The heat of 
 the sun undoubtedly causes the ether of the lower atmosphere 
 to ascend, not by diminution of its specific gravity ; for it has 
 no ponderosity ; but precisely by increase of tension, due to in- 
 crease of motion. This aids the ascensional movement of the 
 air, and therefore, when a vortex is in conjunction with the sun, 
 its action is increased the greatest effect being produced when 
 the vortex comes to the meridian a little before the sun. This 
 has a tendency to make the period of action to appear depend- 
 ent on the phases of the moon, which being the most palpable 
 of all the moon's variations, has been naturally regarded by 
 mankind as the true cause of the changes of the weather. Thus 
 Virgil in his Georgics, speaking of the moon's influence and 
 its signs : 
 
 " Sin ortu in quarto (Namque is certissimus auctor) 
 Pura, nee obtusis per ccelum cornibus ibit ; 
 Totus et ille dies, et qui nascentur ab illo, 
 Exactum ad mensem, pluvia ventisque carebunt." 
 
 Hence, also, in the present day we hear sailors speak of 
 the full and change, or the quartering of the moon, in connec- 
 tion with a gale at sea ; thus showing, at least, their faith 
 in the influence of the phenomenon. Yet it is actually the case, 
 at certain times, that in about latitude 40 and 41, the storms 
 appear about a week apart. 
 
 There is some reason, also, to suspect, that there is a differ- 
 ence of temperature on opposite sides of the sun. As the 
 synodical rotation is nearly identical with the siderent period 
 of the moon, this would require about forty-four years to run its 
 
MECHANICAL THEORY OF STORMS. 109 
 
 course, so as to bring the phenomena to exact coincidence 
 again. Since these observations were made, it is understood 
 that Sig. Secchi has determined that the equatorial regions of 
 the sun are hotter than his polar regions. It may be owing to 
 this fact, that we have inferred a necessity for a change, whose 
 period is a multiple of the sun's synodical rotation, but it is 
 worthy of examination by those who possess the necessary 
 conveniences. 
 
 Another period which must influence the character of differ- 
 ent years, depends on the conjunction of the perigee of the 
 lunar orbit with the node. Taking the mean direct motion of 
 the moon's perigee, and the mean retrograde motion of the 
 node, we find that it takes six years and one day nearly from 
 conjunction to conjunction. Now, from the principles laid 
 down, it follows, that when the perigee of the orbit is due 
 north, and the ascending node in Aries, that the vortices of the 
 earth will attain their greatest north latitude ; and when these 
 conditions are reversed, the vortices will reach their highest 
 limit in the lowest latitude. This will materially affect the 
 temperature of the polar regions. In the following table, we 
 have calculated the times of the conjunctions of the apogee and 
 pole of the orbit, taking the mean motions. It may be conve- 
 nient to refer to by-and-bye, remembering that when the conjunc- 
 tion takes place due south, the vortices reach the highest, but 
 when due north, the vortices in the northern hemisphere have 
 their lowest upper limit : 
 
 CONJUNCTION OF APOGEE AND POLE OF ORBIT.* 
 Year. Month and Day. Longitude. 
 
 1804, . . . April 18th, . . . 220 
 1810, ... " 17th, ... 104 
 
 * It is here assumed, that all the vortices are at their apogee at 
 the same time, and, consequently, they lie in different longitudes , 
 but the central being between, its position is taken for the average 
 position of the three. 
 
110 MECHANICAL THEORY OF STORMS. 
 
 Year. Month and Day. Longitude. 
 
 1816, . . . April 16th, . . . 348 
 
 1822, ... " 15th, ... 232 
 
 1828, ... " 14th, ... 116 
 
 1834, ... " 12th, ... 360 
 
 1840, ... " llth, ... 244 
 
 1846, ... " 10th, ... 128 
 
 1852, ... " 9th, ... 12 
 
 1858, ... " 8th, ... 255 
 
 1864, ... " 7th, ... 139 
 
 1870, ... " 6th, ... 23 
 
 1876, ... " 5th, ... 267 
 
 By this we see that the vortices have never attained their 
 highest limit during the present century, but that in 1858 their 
 range will be in a tolerable high latitude, and still higher in 
 1876 neglecting the eccentricity of the orbit. 
 
 A very potent influence is also due to the heliocentric longi- 
 tude of the sun, in determining the character of any given 
 year. Let us explain : 
 
 The moon's inertia forces the earth from the mechanical 
 centre of the terral system, but is never able to force her clear 
 from the central axis. With the sun it is different. He pos- 
 sesses many satellites (planets). Jupiter alone, from his great 
 mass and distance, is able to displace the whole body of the 
 sun. If other planets conspire at the same side, the centre of 
 the sun may be displaced a million of miles from the mechan- 
 ical centre of the solar system. Considering this centre, there- 
 fore, as the centre of an imaginary sun, from which heliocentric 
 longitudes are reckoned, the longitude of the real sun will vary 
 with the positions of the great planets of the system. Now, 
 although this systematic longitude will not be exactly similar to 
 the heliocentric longitude reckoned from the sun's centre, yet, 
 for the purposes intended, it will correspond sufficiently, and 
 we shall speak of the longitude of the sun as if we reckoned 
 
MECHANICAL THEOKY OF STORMS. 
 
 Ill 
 
 heliocentric longitudes from the mechanical centre of the sys- 
 tem. When we come to consider the solar spots, we shall 
 enter into this more fully. In the following diagram we shall 
 be able to perceive a cause for variation of seasons in a given 
 year, as well as for the general character of that year. 
 
 Let S represent the centre of the sun, and the circle a vertical 
 section of the sun, cutting through the centre, S J being in the 
 equatorial plane of the vortex, of which Z Z' represents the axis. 
 As the ether descends the poles or axis at Z, it is met by the 
 current down the opposite pole, and is thence deflected in radii 
 along the equatorial plane to J. But on the side S, the ether 
 is opposed by the body of the sun ; its direction is consequently 
 changed, and cross currents are produced, assuming it as a 
 principle, that the ethereal fluid is permeable by other currents 
 of similar matter, and that it tends always to move in right 
 lines. This granted, it is evident that, in passing the sun, the 
 quick moving ether 'forms a conical shell, (the sun being at 
 the apex,) so that the strongest current of ether is in this 
 conical shell, or at the surface of this conical space. As the 
 plane of the ecliptic is not much inclined to the sun's equator, 
 and this last probably not much inclined to the plane of the 
 vortex, should the earth have the same heliocentric longitude 
 
112 MECHANICAL THEORY OF STORMS. 
 
 at the time, (or nearly the same,) she would be in an eddy, as 
 respects the radial stream, and be protected from its full force 
 by the body of the sun. 
 
 Now, the ether comes down the axis with the temperature of 
 space, and may possibly derive a little additional temperature 
 in passing over the body of the sun ; so that in this position the 
 earth is protected from the chilling influence of the radial stream, 
 by being protected by the body of the sun. And although, 
 from the immense velocity of the ether, it cannot derive much 
 additional temperature, there may still be an appreciable differ- 
 ence, due to this cause. 
 
 It is the chilling influence of the ethereal stream which orig- 
 inated the idea among philosophers, of frigorific impressions, 
 darted from a clear sky. In some years the sun will be nearly 
 in the centre of the system ; in other years the axis of the vortex 
 will not come near the sun. And as the sun's longitude may 
 vary through the entire circle, it may happen that the earth's 
 longitude shall coincide in winter or summer, or spring or 
 autumn. When, however, the earth emerges from the protec- 
 tion of the sun, and enters the conical shell, considered as a 
 space of considerable depth, she will again be exposed to the 
 full force of the radial stream, rendered more active by the pre- 
 vious deflection, and by the numerous cross currents pervading 
 it ; so that a mild and calm winter may be succeeded by a cold 
 and stormy spring. The present season, (1853,) the earth's 
 longitude coincided with the sun's longitude in about 135, and 
 consequently was in the conical space spoken of, during Feb- 
 ruary and March ; but the radius rector of the sun's centre, 
 being then less than 300,000 miles, the protection was not as 
 complete as it is sometimes. Still, the general fineness of these 
 months was remarkable ; yet in April and May, when the 
 earth became again exposed to the action of the solar stream, 
 the effect was to retard the spring, and disappoint the prognos- 
 tications of the weather-wise. In applying these principles, we 
 
MECHANICAL THEOEY OF STOEMS. 118 
 
 must consider the effect in those latitudes which are more 
 readily affected, that is, in the temperate zone, midway between 
 the two extreme zones of heat and cold. 
 
 In 1837 and 1838, the longitude of the sun's centre corre- 
 sponded with the earth's, in August and September, when there 
 was neither rain nor electrical excitement ; and consequently 
 those seasons were sickly over the whole country. Now, there 
 is another cause which renders the months of August, Septem- 
 ber, and October, deficient in electrical energy, and consequently 
 more prone to be sickly. If, therefore, the two causes unite 
 their influence, the autumnal months will be more sickly at 
 those times. This last cause, however, only affects the northern 
 latitudes in autumn, and consequently, ceteris paribus, the 
 autumnal months should not be so proverbially sickly in the 
 southern hemisphere. This is, however, only suggestive. 
 
 Again, in 1843, the winter was very mild in January and 
 February ; but in March it turned cold and stormy, and con- 
 tinued through April. In this year the longitude of the sun 
 was nearly the same as in 1853, the two longitudes of the 
 earth and sun corresponding about the last of January ; but in 
 March, the earth forsook the comparative calm produced by the 
 sun's position, and hence the greater cold.* 
 
 Thus it appears at every step we take, that the different 
 members of the solar system do indeed belong to the same fam- 
 ily, whose least motions have their influence on the rest. Who 
 could have anticipated that the position of Jupiter in his orbit 
 had anything to do with the health of this remote planet, or 
 with the mildness of its seasons ? In this we have a clue to 
 the origin of that astrological jargon about planetary aspects 
 being propitious or malign. Philosophers are even yet too 
 prone to wrap themselves in their mantle of academic lore, and 
 despise the knowledge of the ancients, while there is reason to 
 
 * It is far from improbable that the effect produced in one zone of 
 climate, may be reversed in another, from the nature of the cause. 
 
114 MECHANICAL THEOEY OF STOEMS. 
 
 believe that the world once possessed a true insight into the 
 structure of the solar system. As war became the occupation 
 of mankind, under the despotic rule of ambition, so truth re- 
 tired, and ignorance seizing upon her treasures, has so mutilated 
 and defaced them, that their original beauty no longer appears. 
 Let us hope that the dawn of a better day is approaching. 
 
 There is yet another cause (just alluded to) which modifies 
 the action of the vortices. 
 
 We have shown that, if the periodic times of the planets are 
 approximately equal to the periodic times of the contiguous 
 parts of the solar vortex, the density of the ether is directly as 
 the square roots of the distances from the centre. As the earth 
 is at her perihelion about the first of January, the density of the 
 surrounding ether is then less than in other parts of the orbit ; 
 consequently, if we suppose that there is a continual tendency 
 to equilibrium, the ether of space must press inwards, during 
 the time between the perihelion and aphelion, (i. e., from Jan- 
 uary to July,) lowering the temperature and increasing the elec- 
 trical action of those months. As the distance from the sun is 
 most rapidly augmenting about the first of April, and the ef- 
 fective power of the sun's radiation is most rapidly increasing in 
 May ; by combining the two we shall find, that about the first 
 of May we shall have considerable electrical action, and cold 
 weather. This explains also, in part, the prevalent tradition of 
 certain days in May being very cold.* When the earth leaves 
 the aphelion, a reaction takes place, being most rapid in Sep- 
 tember. There is then an escape of ether from the earth, 
 which keeps up the temperature, and causes these months to be 
 sickly, from the negative electrical state of the atmosphere. 
 In the southern hemisphere, the effects in the same season will 
 
 * That the llth, 12th, and 13th of May should recede 2 in temper- 
 ature as determined by Masdler from observations of 86 years, at a 
 time when the power of the sun so rapidly augments, is strongly con- 
 firmatory of the theory. See Cosmos, p. 121. 
 
MECHANICAL THEOKY OF STOEMS. 115 
 
 be reversed, which may partly account for the greater degree 
 of cold in that hemisphere, and for accelerating the approach 
 of both summer and winter, while in the north they were both 
 retarded. 
 
 We must now advert to another cause, which of all others is 
 probably the most important, at least to the other members of 
 the solar system. 
 
 In every part of the solar vortex the ether is continually press- 
 ing outwards. We are not now speaking of the radial stream, 
 but of the slower spiral motion of the ether around the axis 
 of the vortex, whose centrifugal force is bearing the whole body 
 of the ether outwards, thus rarefying the central parts, and thus 
 giving rise to the polar influx, from which arises the radial 
 stream. This may be made more intelligible, by reflecting that 
 the polar current is comparatively dense ether, and that the 
 length of the axis of the vortex prevents this influx current 
 coming in sufficient quantities to restore an equilibrium in the 
 density of the medium. Yet, what does come down the poles, 
 is distributed rapidly along the equatorial plane, leaving the 
 space still rarefied. Now we perceive, that in order for the 
 radial stream to continue in action, requires the whole medium 
 of the vortex to be also moving outward ; it is therefore con- 
 tinually condensed as it proceeds. This condensation necessa- 
 rily converts much of the specific heat of the ether into sensi- 
 ble heat ; so that the temperature of the medium is continually 
 increasing, as the distance from the sun increases. 
 
 When we contemplate the solar system as the emanation of 
 one Great Mind, we naturally seek for evidence of the wisdom 
 of a supreme intelligence in all the arrangements of that 
 system. But, however humbly and reverently we may speak 
 of these arrangements, we can scarcely avoid the wish, that the 
 planetary distances had been differently arranged, if Newton's 
 doctrine be true, that space is a vacuum, and that the heat of a 
 planet, is inversely as the squares of the distances from the sun. 
 
116 MECHANICAL THEORY OF STORMS. 
 
 For, to speak of the temperature of space, except as dependent on 
 this law, is one of those many incomprehensible inconsistencies 
 with which philosophers are chargeable. If the Newtonian 
 philosophy is literally true, space has no temperature, and the 
 surface heat of the planet Neptune is nearly 1,000 times less 
 than on our own globe. Again, on Mercury it is seven times 
 greater, which heat would scorch and consume every organic 
 substance on the earth, and speedily envelope the boiling ocean 
 in a shroud of impermeable vapor. Granting even that space 
 may not be a vacuum, and yet the law of gravitation be true, 
 we may still be allowed to consider both Saturn and Uranus 
 and Neptune, as inhospitable abodes for intelligent creatures ; 
 and, seeing the immensity of room in the system, there is no 
 reason why these planets might not have been permitted to 
 revolve nearer the great source of light and life and cheering 
 emanations. To suggest the resources of Omnipotence is no 
 argument. He has surrounded us with analogies which are 
 seen, by which we may attain a knowledge of those which are 
 not seen ; and we have every reason to suppose that the great 
 Author of nature is not indifferent to the aspects under which 
 his works reveal him unto his creatures. Yet there is (on the 
 above hypothesis) an apparent want of harmony in the plane- 
 tary distances; and if frail mortality may be permitted to 
 speak out, an explanation is needed to obviate this seeming 
 anomaly in the economy of the world. The more we learn of 
 the physical arrangements of the universe, the more do they 
 correspond with our experience of the nice adaptation of the 
 means to the end which obtains in our own globe, and we can 
 only judge of other planets by the analogies around us. Here, 
 there, are extremes of temperature it is true : it is necessary 
 there should be, and we can see and understand the necessity 
 in all such, cases, and how they conduce to the general average 
 of good. But, astronomers can give no reason why it is neces- 
 sary that some planets of our system should be placed so 
 
MECHANICAL THEOEY-OF STOKMS. 117 
 
 remote that the sun is frittered down to a star, whose heatless 
 light is but a mockery to those frigid realms. 
 
 Now, according to this theory, the temperature of Neptune 
 may be far more uniform and conducive to life than that of our 
 own globe. The chilling influence of the solar stream at that 
 planet being nearly null, and the temperature of the surround- 
 ing space far greater. So also Mercury, instead of being the 
 burning planet of the schools, may suffer the most from cold. 
 
 The planet Mars is generally considered, of all the members 
 of the system, most nearly to resemble our own world. The 
 telescope not only reveals seas and continents, but the snowy 
 circles round his poles, which appear to increase and diminish, 
 as his winter is beginning or ending. This planet's ecliptic is 
 similar to our own in inclination or obliquity, his distance, 
 also, is far greater, and his winter longer ; yet, for all this, his 
 snow zones are less than on our own globe. This anomalous 
 fact has, we believe, never been noticed before ; but it is expli- 
 cable on the theory, and therefore confirms it. Mars has no 
 satellite, and therefore his centre will be coincident with the 
 centre of the marsial vortex. There will be no lateral vortices 
 to derange his atmosphere, and if the axis of his vortex coin- 
 cides also with the axis of the planet, the central vortex will be 
 continually over the poles, and there will be no storms on the 
 planet Mars. A capital fact connected with this, is the want 
 of belts, as in Jupiter and Saturn ; for these planets have satel- 
 lites, and if they are not massive enough, the belts may be 
 produced by an obliquity in the axis of the Jovial and Satur- 
 nial vortices. If Mars had an aurora like the earth, it is fair 
 to presume the telescope would ere this have shown it. He is, 
 therefore, in equilibrium. In applying this reasoning to the 
 earth, we perceive that a certain influence is due to the differ- 
 ence of temperature of the ethereal medium surrounding the 
 earth, at perihelion and aphelion, being least at the former, and 
 greatest at the latter. 
 
118 
 
 MECHANICAL THEORY OF STORMS. 
 
 As a modifying and interfering cause in the action of the 
 vortices, we must mention the great natural currents of the atmos- 
 phere, due to the earth's rotation. 
 
 It is considered that the sun is the principal cause of these 
 great currents. By elevating the surface atmosphere of the 
 equator, a lateral current is induced from the north and south ; 
 but on account of the enlarging circles of latitude, their direc- 
 tion tends more from the north-east and south-east. These cur- 
 rents are usually called the trades. Without disputing the 
 correctness of this, it may be doubted whether the whole effect 
 is due to the sun. As this principle affects the ocean likewise, 
 it is necessary to look into it ; and in order to simplify the ques- 
 tion, we will first suppose our globe covered entirely by the 
 ocean, without any protuberant land. 
 
 Let us assign a uniform depth of ten miles to this ocean. In 
 the Fig. following, the two circles will represent the surface 
 and bottom of the ocean respectively. The axis of rotation 
 
 m 
 
 is thus represented by the line P P'. Let us consider two 
 particles of water at m and n, as feeling the influence of this 
 rotation ; they will, of course, be both urged towards the 
 equator by the axifugal force. Now, every particle in the ocean 
 being also urged by the same force, it might be suppos-ed that 
 
MECHANICAL THEORY OF STORMS. 119 
 
 after a protuberant mass of water had accumulated at the 
 equator E E', the whole ocean would be in equilibrium. This 
 would not follow. The particle at m is urged by a greater force 
 than n ; consequently the particle at n is overborne by the press- 
 ure at m. Considering both in the same direction, yet the 
 particle at n must give way, and move in the opposite direction. 
 Just as the heaviest scale of the balance bears up the lightest, 
 although both gravitate towards the same point. This is so 
 self-evident that it would seem unnecessary to dwell upon it, 
 had not the scientific world decided that the rotation of the 
 earth can cause no currents either in the atmosphere or in the 
 ocean. 
 
 The axifugal forces of the two particles m and n are directly 
 as the lines M m and N n, and if the gravitating forces were 
 also as the radii T m and T , no motion would be produced. 
 Admitting even the Newtonian law to be rigidly exact, the 
 earth cannot be considered a homogeneous globe, but, on the 
 contrary, the density of the central parts must be nearly thirty 
 times greater than the density of the surface of the ocean. The 
 ratio of the gravitating forces of these two particles is, therefore, 
 less than the ratio of their respective radii, and the axifugal ten- 
 dency of the particle at n is more than proportionally restrained 
 by the central gravitation ; and hence m will move towards the 
 equator, and n towards the poles, as represented in the Fig. 
 
 It is on account of the overwhelming momentum of the sur- 
 face waters of the South Pacific over the North, that the Pacific, 
 at Panama, stands six or seven feet higher than the Atlantic. 
 We shall again allude to this interesting fact. 
 
 According to newspaper reports of a lecture, delivered in New 
 York, by Lieut. Maury, U. S. N., this gentleman endeavors to 
 explain the currents of the ocean, by referring them to evapora- 
 tion in the tropics. The vapor leaves the salt of the water be- 
 hind, and thus, by continual accumulation, the specific gravity 
 of the tropical waters is greater than that of the superficial 
 
120 MECHANICAL THEORY OF STORMS. 
 
 waters nearer the poles ; the lighter water, therefore, passes to- 
 wards the equator, and the heavier water below, towards the 
 poles. If this be a correct statement of that gentleman's theory, 
 fidelity to our standards compels us to question the soundness 
 of the conclusion. The mere fact of the surface water of the 
 ocean being lighter than that of the bottom, cannot on any 
 known principles of science cause any movement of the surface 
 waters towards the equator. When such an acute and practical 
 physicist is driven, by the palpability of the fact that the polar 
 waters are continually tending towards the equator, to seek the 
 cause in the tropical evaporation, it shows that the dogma, which 
 teaches that rotation can produce no motion, is unsound. 
 
 Sir John Herschel, in speaking of the solar spots, says : " We 
 may also observe that the tranquillity of the sun's polar, as 
 compared with his equatorial regions (if his spots be really 
 atmospheric), cannot be accounted for by its rotation on its 
 axis only, but must arise from some cause external to the sun, 
 as we see the belts of Jupiter and Saturn and our trade winds 
 arise from a cause external to these planets combining itself 
 with their rotations, which alone (and he lays an emphasis on 
 the word) can produce no motions when once the form of 
 equilibrium is attained." 
 
 With respect to the origin of the solar spots, we have no 
 disposition to question the conclusion ; but, as regards the 
 principle laid down, that rotation can produce no motions when 
 once the form of equilibrium is attained, we must unequivocally 
 dispute it. If our atmosphere were of uniform density, the 
 rotation of the earth would cause no current such as we have 
 described ; with our atmosphere as it is, the result will be 
 different. The momenta of two portions of matter are the 
 products of their inertiae by their motions, and, in the present 
 case, we must take the inertiae of equal spaces. A cubic inch 
 of air at the surface, and at three miles above the surface, is as 
 2 to 1 ; but their centrifugal velocity varies only as the radii 
 
MECHANICAL THEORY OF STORMS. 121 
 
 of the respective spheres, or as 1320 to 1321. In the polar 
 regions, therefore, the momentum of the surface air preponder- 
 ates, and, in this case, the surface current is towards the 
 equator, and the upper current towards the poles. When, 
 however, the centrifugal velocity is considerably increased in a 
 lower latitude, and the curvature of the surface becomes more 
 and more inclined to the direction of that resolved part of the 
 centrifugal force, which is always from the axis, the surface 
 layers will evince a tendency to leave the surface, and an inter- 
 mingling will then take place in the space between latitude 70 
 and 50, or in latitude 60. As this layer is continually urged 
 on in the same direction by the surface layer of latitudes above 
 60, the upper layer now becomes a current setting towards the 
 equator, and, consequently, the back current occupies the sur- 
 face. Now, considering that the rarefying action of the sun is 
 elevating the air under the equator, there must necessarily be 
 an upper current from the equator to the poles ; so that if we 
 conceive the two currents to meet about latitude 30, there will 
 be a second intermingling, and the current from the poles will 
 again occupy the surface. Thus, we regard a part of the effect 
 of the trades to the rotation of the earth, which is the chief 
 impelling power at the poles, as the sun is at the equator ; and 
 the latitudes 60 and 30 will be marked by some especial 
 phenomena of temperature, and other meteorological features 
 which do actually pbtain. These would be much more marked 
 if the irregular configuration of land and sea, the existence of 
 mountain chains, and the different heating power of different 
 latitudes, owing to the unequal distribution of the land, did not 
 interfere ; and the currents of the air (disregarding the deflec- 
 tion east and west) might then be represented by a treble link 
 or loop, whose nodes would vary but little from latitudes 30 
 and 60. As it is, it has, no doubt, its influence, although 
 unimportant, when compared with the disturbing action of the 
 ethereal vortices. 
 
 6 
 
122 MECHANICAL THEOEY OF STOEMS. 
 
 There is another phenomenon due to the action of the radial 
 stream, which has given much trouble to the physicist, and 
 which has yet never been explained. This is the horary oscil- 
 lations of the atmospheric pressure which, in some countries, 
 are so regular that the time of day may be ascertained by the 
 height of the barometer. According to Humboldt, the regu- 
 larity of the ebb and flow in the torrid regions of America, is 
 undisturbed by storms or earthquake. It is supposed that the 
 maxima occur at 9 A. M. and 10 J p. M., and the minuima at 4 
 A. M. and 4 p. M. From the morning minimum to the morn- 
 ing maximum is, therefore, five hours ; from the evening 
 minimum to the evening maximum is 6 J hours ; from the 
 evening maximum to the morning minimum is 5j hours, and 
 from the morning maximum to the evening minimum is 7J 
 hours. Again, these oscillations are greatest at the equator, 
 and diminish with the increase of latitude. 
 
 , 23 
 
 If we suppose the earth's axis perpendicular to the plane of 
 the vortex, and P the pole in the above figure, and S P the 
 line joining the centre of the earth and sun, M and m will rep- 
 resent the points in the earth's equator where it is midday and 
 midnight respectively. The solar stream penetrates the terral 
 vortex, and strikes the earth's atmosphere along the lines par- 
 
MECHANICAL THEORY OF STORMS. 123 
 
 allel to S P. The direct effect would be to pile up the atmos- 
 phere at N and n ; and therefore, were the earth at rest, the 
 maximum would be at 6 A. M. and 6 p. M., and the minimum at 
 midday and midnight ; but the earth rotating from N towards 
 M, carries along the accumulated atmosphere, being more slug- 
 gish in its motions than the producing cause, which cause is 
 still exercised to force it back to N. From this cause the maxi- 
 mum is now found at K. For a like reason the minimum at 
 M would be found at L, but on account of the motion of the 
 earth being now in the same direction as the solar stream, the 
 minimum is found still more in advance at Jc ; so that, accord- 
 ing to the theory, the interval between the morning maximum 
 and the evening maximum, should be greater than the interval 
 between the evening maximum and the morning maximum ; 
 and so it is, the first being 13J hours and the last 10-j- hours. 
 The morning minimum should also be less marked than the 
 evening minimum, and this also is a fact. The effect also 
 should be greater in the tropics than in high latitudes, which 
 again also obtains ; being 1.32 French lines at the equator, and 
 only 0.18 at latitude 70. Had the earth no obliquity, the ef- 
 fect would be as the squares of the cosines of the latitude ; 
 but the ratio is diminished by the inclination of the axis. But 
 there are other variations of the barometer of longer period, 
 apparently depending on the phases of the moon, but which 
 cannot be reconciled to the attracting power of the moon as 
 an atmospheric tide ; and Arago concluded that they were due 
 to some special cause, of which the nature and mode of action 
 are unknown. Perhaps this theory will obviate the difficulty, 
 as although the central vortex comes to the meridian at the 
 same time as the moon, its effect will be different on the infe- 
 rior meridian to what it is on the superior one ; whereas the 
 moon's attraction should be the same on both'. That the pas- 
 sage of a vortex over or near a particular place should affect 
 the barometer, is too obvious to need explanation, and therefore 
 
124 MECHANICAL THEOEY OF STOEMS. 
 
 we may say that the theory will explain all those varieties, 
 both small and great, which have caused so much speculation 
 for the last fifty years. 
 
 TERRESTRIAL MAGNETISM. 
 
 In applying the theory to the magnetism of the earth, we 
 must bear in mind that the earth is probably magnetic by in- 
 duction, and not in virtue of its own specific action. The rota- 
 tion of the surrounding ether, and the consequent production of 
 a radial stream, calls the ether into motion within the earth's 
 interior, as well as on the surface ; but it does not follow that 
 the ether shall also enter the earth at its poles and escape at 
 its equator, for the obliquity of the vortex would interfere with 
 this result. It is sufficient that this does occur in the terral 
 vortex immediately surrounding the earth. From late experi- 
 ments it is pretty well established that the axial direction of 
 the needle, (and of other bodies also,) is due to peculiar inter- 
 nal arrangement in laminae or layers, the existence of which is 
 favorable to the passage of the magnetic current. 
 
 According to the experiments* of Dr. Tyndal, it is found that 
 the magnetism of a body is strongest along the line of greatest 
 density. As, therefore, the laminae of bodies may be considered 
 planes of pressure, when these planes are suspended horizontally, 
 the directive force is greatest, and the longest diameter of the 
 body sets axial. On the other hand, when the body was sus- 
 pended so that the laminae were vertical, the longest diameter 
 set equatorial. Now, we know that the crust of the earth is 
 composed of laminae, just as the piece of shale in Doctor 
 Tyndal's experiments, and that these layers are disposed hori- 
 zontally. And whatever force originally arranged the land and 
 water on our globe, it is evident that the continents are longest 
 
 * Plucker first discovered that a plate of tourmaline suspended 
 with its axis vertical, set axial, 
 
MECHANICAL THEORY OF STORMS. 125 
 
 from north to south, and therefore correspond to the natural 
 direction of the magnetic force. 
 
 In consequence of the intrinsic difficulties of this question, and 
 the mystery yet attaching to it, we may be permitted to enter a 
 little more minutely into it, and jointly consider other questions 
 of interest, that will enable us to refer the principal phenomena 
 of terrestrial magnetism to our theory. 
 
 We have before adverted to the discrepancies in the earth's 
 compression, as determined by the pendulum, and also to the 
 uncertainty of the moon's mass, as deduced from the nutation 
 of the earth's axis. It is also suspected that the southern 
 hemisphere is more compressed than the northern ; and other 
 phenomena also point out the inadequacy of the law of gravita- 
 tion, to account for the figure of the earth. 
 
 From the invariability of the axis of rotation, we must con- 
 clude that whatever form is the true form, it is one of equilib- 
 rium. In casting our eyes over the map of the world, we per- 
 ceive that the surface is very unequally divided into land and 
 sea ; and that the land is very unequally arranged, both north 
 and south, and east and west. If we compare the northern and 
 southern hemisphere, we find the land to the water about 3 to 
 1. If we take the Pacific portion, and consider the north end 
 of New Zealand as a centre, we can describe a great circle 
 taking in one half the globe, which shall not include one-tenth 
 of the whole land. Yet the average height of the remaining 
 nine-tenths, above the level of the sea, is nearly 1,000 feet. Call 
 this nine-tenths nearly equal to one-fourth of the whole surface, 
 and the protuberant land in the hemisphere, opposite the South 
 Pacific, amounts to T T ,VTTT P art f ^ e whole mass of the earth, 
 or about j-$ of the mass of the moon. Again, the mean 
 density of the earth is about 5^, water being unity, and 
 the mean density of the surface land is only about half this ; 
 but three-fourths of the whole surface is water. Hence, we see 
 that the materials of the interior of the earth must be either 
 
126 MECHANICAL THEOEY OF STORMS. 
 
 metallic or very compressible. To assign a metallic nucleus to 
 the earth, is repugnant to analogy ; and it is not rendered even 
 probable by facts, as we find volcanic emissions to contain no 
 heavier elements than the sedimentary layers. Besides, there 
 are indications of a gradual increase of density downwards, such 
 as would arise from the compressibility of the layers. Seeing, 
 therefore, the equilibrium of the whole mass, and the consequent 
 hydrostatic balance of the land in the sea, seeing also the 
 small compressibility of the solid portions, and the great com- 
 pressibility of the fluid, the inference is legitimate that the whole 
 is hydrostatically balanced, and that our globe is a globe of 
 water, with an intermediate shell of land, specifically lighter 
 than the fluid in which it is suspended. Where this shell is of 
 great thickness, it penetrates to greater depths, and attains to 
 greater elevations above the surface of the aqueous globe ; where 
 it is less thick, it is found below the surface, and forms the bot- 
 tom of the upper ocean. Recent soundings give much greater 
 depths to some parts of the ocean, than the most elevated land 
 upon the globe. Captain Denham, of H. B. M. ship Herald, 
 lately sounded in 37 south and 37 west, and found bottom at 
 7,706 fathoms, or about nine English miles. 
 
 As the interior portions of our globe are totally unknown, and 
 the compressibility of water is well established, it is just as sane 
 to consider water the most abundant element of nature, as solid 
 land. The great question to ask is, whether there may not be 
 other phenomena incompatible with this supposition ? It is 
 plain that the permanency of terrestrial latitudes and longitudes 
 would be unaffected by the conditions we have supposed. 
 Would the precession of the equinoxes be also unaffected ? Mr. 
 Hopkins has entered into such an investigation, and concludes : 
 " Upon the whole, then, we may venture to assert that the 
 minimum thickness of the crust of the globe, which can be 
 deemed consistent with the observed amount of precession, can- 
 not be less than one-fourth or one-fifth of the radius of the 
 
MECHANICAL THEOKY OF STOKMS. 127 
 
 earth." These investigations were made on the hypothesis of the 
 interior fluidity being caused by the fusion of the central por- 
 tions of a solid globe ; but it is evident that the analytical re- 
 sult would be the same if these central parts were water, in- 
 closed by an irregularly-spherical shell of land. Nor would 
 the result be affected, if we considered certain portions of the 
 interior of this solid shell to be in a state of fusion, as no doubt 
 is the case. 
 
 May not the uncertainty of the mass of the moon, be owing 
 to the fact that this shell is not so rigidly compacted but that it 
 may yield a little to external force, and thus also account for 
 the tides in the Pacific groups, rather obeying the centrifugal 
 force due to the orbit velocity of the earth, than the attraction 
 of the moon ? 
 
 Since the days of Hipparchus the sidereal day has not 
 diminished by the hundreth part of a second ; and, consequently, 
 seeing that the contraction of the mass must be limited by the 
 time of rotation, it is inferred that the earth has not lost 3^5- th 
 of one degree of heat since that time. This conclusion, sound 
 as it is, is scarcely credible, when we reflect on the constant 
 radiation into a space 60 below zero. Admit that the globe 
 is a globe of water, whose average temperature is the tem- 
 perature it receives from the sun, and the difficulty vanishes 
 at once. Its diameter will be invariable, and the only effect 
 of the cooling of the solid parts will be to immerse them 
 deeper in the water, to change the relative level of the sea 
 without changing its volume. This is no puerile argument when 
 rightly considered ; but there is another phenomenon which, if 
 fairly weighed, will also conduct us to the same views. 
 
 It is now a fact uncontroverted, that the sea does actually 
 change its level, or rather, that the elevation of continents is 
 not only apparent but real. The whole coast of Sweden and 
 Finland is rising at the present day at the rate of four feet in a 
 century, while on the south a contrary effect is produced. Vari- 
 
128 MECHANICAL THEOKY OF STOEMS. 
 
 ous hypotheses have been formed concerning this interesting 
 fact. Yet from the indications of geology, it must have been an 
 universal phenomenon in the early ages of the world, in order 
 to account for the emersion of sedimentary deposits from the 
 fluid which deposited them. May not internal fires be yet 
 spreading, and the continents expanding instead of contracting ? 
 And may there not be an inequality in this process, so as neces- 
 sarily to immerse in one direction nearly as much as to elevate 
 in another ? One fact is certain, the elements are scattering 
 the materials of the land along its Oceanic coasts, which of it- 
 self must produce a very minute effect in disturbing the hydros- 
 tatic balance ; but a more efficient agent is the earthquake and 
 volcano. 
 
 The upheaving of tracts of land by earthquakes, as on the 
 coast of Chili, would thus be satisfactorily explained, by attri- 
 buting a certain resistance due to cohesion or friction preventing 
 a gradual change of level, but producing it suddenly by the jar 
 of the earthquakes. May we not inquire also, whether the 
 facility with which the earth seems moved by this destructive 
 agent, does not point to the same solution as the irregularity of 
 the figure of the earth ? 
 
 This is a subject on which it is allowable to speculate, espe- 
 cially if any light can be thereby thrown on the still more mys- 
 terious source of terrestrial magnetism. It is for such a purpose 
 that we have permitted ourselves to digress from that subject. 
 In this connection we also may acknowledge our indebted- 
 ness to the sacred volume for the first germ of this theory of the 
 weather. 
 
 Believing in the authenticity of the Mosaic history of the del- 
 uge, the author found it difficult to refer that event to other 
 than natural causes, called into action by the operation of other 
 causes, and all simultaneous with the going forth of the fiat of 
 Omnipotence. Thus reasoning, he was led to regard the deluge 
 as a physical phenomenon inviting solution, and as a promising 
 
\ 
 
 MECHANICAL THEORY OF STORMS. 129 
 
 exponent to the climatology of the early world. He looked 
 upon the bow of promise, as the autograph of the Creator, the 
 signature to a solemn bond, upon which the eye of man had 
 never before rested. But if there was no rainbow before the 
 deluge, there was no rain ; and following up this clue, he was 
 not only enabled to solve the problem, but also led to the true 
 cause, which produces the principal commotions in our atmos- 
 phere. 
 
 Science boasts of being the handmaid of religion ; yet there 
 are names of note in her ranks who have labored rather to in- 
 vest this phenomenon with the mantle of fable, and to force it 
 into collision with the records graven on the rocky pages of 
 geognosy. But the world is ever prone to be captivated by 
 the brilliancy of misapplied talents, instead of weighing merit 
 by its zeal in reconciling the teachings of those things which 
 are seen, with those which are revealed. 
 
 If our globe be constituted as we suppose, the land might 
 experience repeated submersions, without involving the neces- 
 sity of any great departure from established laws. And we 
 might refer to the historical record of one of these, with all the 
 minute particulars as positive data, imposing on us the necessity 
 of admitting that the solid parts of the globe are hydrostatically 
 balanced in the sea. But, modern science is not always cor- 
 rectly defined when called the pursuit of truth, nor human 
 learning the means of discovering it. 
 
 If we could divest ourselves of this prejudice, we should have 
 a ready solution of the difficulty presented by the earth having 
 two north magnetic poles, and probably two also in the south. 
 For, by regarding the old and new continents as two distinct 
 masses of land whtfse bases are separated by 6,000 miles of 
 water, we recognize two great magnets, dependent, however, for 
 their magnetism, on the rotation of the terral vortex. 
 
 This is no place to enter into a lengthy discussion of such a 
 difficult subject as magnetism, but we may be allowed to enter 
 6* 
 
130 MECHANICAL THEORY OF STORMS. 
 
 a protest against the current theory of electro-magnetism, viz. : 
 that a force is generated by a galvanic current at right angles 
 to the producing cause, which is contrary to the fundamental 
 principles of mechanics. We may conceive that a current is 
 induced from or to the surrounding space by the rarefaction 
 or condensation attending the transmission of such a current 
 along a wire, and that rotation should follow, just as a bent 
 pipe full of small holes at the lower end, and immersed in water 
 as a syphon, will generate a vorticose motion in the water ; but 
 mere juxtaposition, without participation and communication 
 with the general current, is irrational, and, therefore, not true. 
 
 We have always regarded a magnetic needle as a part of the 
 great natural magnet, the earth ; that its north pole actually 
 points to the north, and its south pole to the south ; and, being 
 free to move, it is affected by the circular motion of the sur- 
 rounding ether, and by every motion by which the ether is 
 directed. If there was any attraction between the earth and 
 the needle, opposite poles would be presented, but it is not so 
 the force is merely directive. 
 
 MAGNETIC VARIATIONS. 
 
 Let us now see whether we cannot assign an adequate cause 
 for the secular and periodic variations in the inclination and 
 declination of the needle. These have been generally referred 
 to changes of temperature, as in fact, also, the magnetism of 
 the earth is sometimes ascribed to galvanic or electric currents, 
 called forth by a daily change of temperature. Our theory 
 gives a totally different explanation of these variations. 
 
 In the northern hemisphere, the north point of the needle 
 moves from east to west in the morning from about 8-J- A. M. to 
 1^- P. M., and returns to its mean position about 10 p. M. It 
 then passes over to the east, and again returns to its mean 
 position about 8 or 9 A. M. The analogy of this motion, with 
 
MECHANICAL THEOKY OF STOKMS. 131 
 
 the horary changes in the barometer, indicate a common origin. 
 Humboldt, in the instructions he drew up for the Antartic 
 Expedition under Sir James Ross, says : " The phenomena of 
 periodical variations depend manifestly on the action of solar 
 heat, operating probably through the medium of thermo 
 electric currents induced on the earth's surface. Beyond this 
 rude guess, however, nothing is yet known of their physical 
 cause. It is even still a matter of speculation whether the solar 
 influence be a principal or only a subordinate cause." That 
 the sun may exert a modifying influence on the phenomenon 
 is not unlikely, but that he cannot be the principal cause, is 
 evident from the following considerations. These horary 
 variations of the magnetic needle are as great at the bottom of 
 deep mines far removed from solar influence, as on the surface. 
 They are as great, ceteris paribus, on a small island in the 
 midst of the ocean, as in the interior of continents, where the 
 heating power of the surface is vastly greater. They are ex- 
 tremely regular, so that between the tropics, according to the 
 sagacious Humboldt, "the time of the day may be known by 
 the direction of the needle, as well as by the height of the 
 barometer." 
 
 But what is the cause of these variations ? This question is 
 the most difficult of all physical problems, and we shall only 
 aim at indicating the causes which are yet perhaps too intri- 
 cately involved to afford a positive numerical determination. 
 Admitting the existence of two principal solid masses whose 
 general direction is from south to north, and that these masses 
 are more susceptible of permeation by the ethereal fluid than 
 the waters in which they are suspended, we have a general 
 solution of the position of the magnetic poles, and of the 
 isogonic, isoclinic, and isodynamic lines. Considering, too, 
 that the southern poles of these masses are the points of ingress, 
 and the northern poles the points of egress, it is easily under- 
 stood that the ethereal medium having the temperature of 
 
132 MECHANICAL THEOKY OF STOEMS. 
 
 space, will cause the southern hemisphere to be colder than 
 the northern, and also that the magnetic poles will be the poles 
 of maximum cold, and the centres respected by the isothermal 
 and isogeothermal lines. 
 
 The general direction of the magnetism of the earth may be 
 considered as the controlling influence, therefore, in determining 
 the position of the magnetic needle ; but there are other causes 
 which, to some extent, will modify the result. That half of 
 the globe turned away from the sun will partake of the density 
 of the ether at that distance, which is greater than on the side 
 next the sun; the magnetic intensity ought, therefore, to be 
 greater in the night than in the day. The poles of the great 
 terrestrial magnets, or even the position of a magnetic needle 
 on the surface, are continually placed by the earth's rotation in 
 a different relation to the axes of the terral vortex, and the 
 tangential current, which is continually circulating around the 
 globe, has its inclination to a given meridian in a perpetual 
 state of change. If we conceive that there is a tendency to 
 force the needle at right angles to this current, we shall have 
 an influence which varies during the day, during the year, and 
 during the time occupied by a complete revolution of the node. 
 The principal effect, however, of the horary variation of the 
 needle is due to the radial stream of the sun, which not only 
 penetrates the atmosphere, but also the solid crust of the earth. 
 Its principal influence is, however, an indirect influence, as we 
 shall endeavor to explain. 
 
 No fact in the science of electro-magnetism is, perhaps, better 
 established than the disposition of an ethereal current to place 
 itself at right angles to the magnetic meridian, and conversely, 
 when the current is not free to move, to place the needle at 
 right angles to the current. Now, the terrestrial magnet or 
 magnets, may be considered to be surrounded by a body of 
 ether in rotation, which, in the earth, on its surface, and for 
 some distance from the surface, is made to conform to the 
 
MECHANICAL THEORY OF STORMS. 133 
 
 general rule, that is, to circulate at right angles to the magnetic 
 meridian. Outside this again, the ether more and more con- 
 forms to the position of the axis of the vortex, and this position 
 varying, it must exert some influence on the surface currents, 
 and, therefore, change in some degree the position of the 
 magnetic meridian. The radial stream comes from the sun in 
 parallel lines, and strikes the globe and its superficial ethereal 
 envelope just as we have shown its action on the atmosphere; 
 but in this last case the magnetic equator is not a great circle, 
 neither can we suppose its effects to be an accumulation of a 
 fluid which is imponderable at points 90 from the plane 
 passing through the centre of the earth and sun, and coincident 
 with the plane of the central meridian, and a depressing effect 
 on that meridian. Its precise influence must be, from, the 
 nature of the cause, to deflect the circular current towards the 
 poles, in places less than 90 from the meridian, and a contrary 
 effect must be produced in places greater than 90 from the 
 meridian. Let us assume, for argument's sake, that the mag- 
 netic poles of the earth correspond to the poles of rotation, the 
 parallels of latitude will, therefore, represent the ethereal cur- 
 rents circulating around the globe. Now, at sunrise, the radial 
 stream of the solar vortex is tangential to the surface, and, 
 therefore, can produce no change in these currents. As the sun 
 ascends say about 8 or 9 A. M., the radial stream striking only 
 the surface of the earth perpendicularly in that place where the 
 sun is vertical (which we will suppose at the equator), streams 
 off on every side, as the meridians do from the pole, and the 
 circles of latitude (that is the ethereal currents) being parallel 
 to the equator, they are met by the radial stream obliquely, 
 and deflected towards either pole. By this deflection they are 
 no longer at right angles to the meridians. But, from the 
 principle of reaction above noticed, the magnetic meridians will 
 place themselves at right angles to the current, or, in other 
 words, the magnetic pole will change its position on the surface 
 
134 
 
 MECHANICAL THEORY OF STORMS. 
 
 of the earth with respect to that particular place. But, in 
 other parts of the world, the meridians are in opposite phases 
 at the same instant of absolute time; therefore, the magnetic 
 poles are not points, but wide areas enclosing the magnetic 
 poles of all the countries under the sun. As this conforms to 
 observation, it is worthy our especial attention, and may be 
 understood by the subjoined figure, in which the oblique curves 
 represent the course of the tangential current in the different 
 positions of the sun, the parallel lines representing the solar 
 radial stream. 
 
 As the sun gains altitude the action of the radial stream is at 
 a greater and greater angle to the circular currents, and attains 
 its maximum at noon, still acting, however, after noon ; but see- 
 ing that the circular current possesses a force of re-action, that is, 
 that the magnetism of the earth is ever striving to bring these 
 currents to their natural direction, an hour or two after noon, 
 the currents tend again to the equator, and the maximum de- 
 flection is passed, and finally ceases a few hours after sunset. 
 Now let us attend to what is going on on the opposite side of 
 the world. The radial stream passing over the polar regions, 
 now produces a contrary effect : the ethereal atmosphere of the 
 great magnet is accumulated on the farthest side from the sun, 
 
MECHANICAL THEOEY OF STORMS. 135 
 
 by the action of the radial stream passing over the polar region, 
 the parallel currents are now bent towards the equator, being at 
 a maximum in places where it is an hour or two past midnight. 
 Before they were concave to the equator, and now they are 
 convex ; the magnetic meridian is therefore deflected the con- 
 trary way to what it was in the day time, by the same princi- 
 ple of reaction. After the maximum, say at 4 A. M., the de- 
 flection gradually ceases, and the magnetic meridian returns to 
 its mean position at 8 or 9 A. M. These times, however, of 
 maximum and minimum, must vary with the time of the year, 
 or with the declination of the sun, with the position of the 
 moon in her orbit, with the perigee of the orbit, and with the 
 place of the ascending node ; there are also minor influences 
 which have an effect, which present instrumental means cannot 
 render appreciable. 
 
 What says observation ? The needle declines from its mean 
 position in the whole northern hemisphere to the westward, 
 from about 8.30 A. M., until 1.30 p. M. ; it then gradually re- 
 turns to its mean position by 10 A. M. After 10 p. M., it passes 
 over to the eastward, and attains its maximum deflection about 
 three or four hours after midnight, and is found again at its mean 
 position about 9 A. M. Now, this is precisely the direction of 
 the deviation of the magnetic meridian, the needle therefore 
 only follows the meridian, or still continues to point to the tem- 
 porary magnetic pole. And although we have assumed, for the 
 sake of simplicity, that the mean magnetic pole corresponds to 
 the pole of rotation ; in truth there are two magnetic poles, 
 neither of which correspond ; yet still the general effect will be 
 the same, although the numerical verification will be rendered 
 more difficult. 
 
 In the southern hemisphere the effect is the reverse, (this 
 southern hemisphere, however, must be considered separated 
 from the northern by the magnetic equator, and not by the 
 geographical one,) the needle declines to the eastward in the 
 
136 MECHANICAL THEORY OF STORMS. 
 
 morning, and goes through the same changes, substituting east 
 for west, and west for east. Does observation decide this to be 
 to be a fact also ? Most decidedly it does ; and this alone 
 may be considered a positive demonstration, that the theory 
 which explains it is true. The contrary deflection of the needle 
 in the northern and southern hemisphere may be formally 
 proclaimed as utterly beyond the reach of the common theory 
 of magnetism to explain. This difficulty arises from consider- 
 ing the needle as the disturbed body instead of the earth ; and 
 also from the fact that the effect of solar heat must be common 
 to needles in both hemispheres, and act upon similar poles, and 
 consequently the deflection must be in the same direction. 
 
 But a still more capital feature is presented by the discovery 
 of Colonel Sabine, that the deflection is in contrary directions 
 at the Cape of Good Hope, at the epoch of the two equinoxes. 
 This arises from the great angle made by the magnetic meridian 
 at this place, with the terrestrial meridian the variation being 
 by Barlow's tables, 30 to the westward. The sun varies in 
 declination 47 throughout the year. At the southern solstice, 
 therefore the radial stream strikes the circular current on the 
 southern side, and deflects it towards the equator, rendering the 
 declination to the westward in the morning ; but at the northern 
 solstice the radial stream strikes the current on its northern 
 side, and the deflection is eastward in the morning. And the 
 vicinity of the Cape of Good Hope is, perhaps, the only part of 
 the world where this anomaly will obtain ; as it is necessary not 
 only that the declination shall be considerable, but also that 
 the latitude shall not be very great. 
 
 Observation also determines that the amount of the horary 
 variation increases with the latitude. Near the equator, accord- 
 ing to Humboldt, it scarcely amounts to three or four minutes, 
 whilst it is from thirteen to fourteen minutes in the middle of 
 Europe. The theory explains this also ; for as the circles recede 
 from the equator, the angles made by their planes with the 
 
MECHANICAL THEORY OF STORMS. 137 
 
 direction of the radial stream increases, and hence the force of 
 deflection is greater, and the effect is proportioned to the cause. 
 We have also a satisfactory explanation of the fact that there 
 has not yet been discovered a line of no variation of horary decli- 
 nation as we might reasonably anticipate from the fact that the 
 declinations are in contrary directions in the northern and 
 southern hemisphere. This is owing to the ever-varying decli- 
 nation of the sun. There would be such a line, no doubt, if the 
 axis of the earth were perpendicular to the plane of the orbit, 
 and the magnetic pole coincided with the pole of rotation : for 
 then the equator would be such a line. 
 
 MAGNETIC STORMS. 
 
 But there are also irregular fluctuations in the direction of the 
 magnetic needle. These depend on the moon, and are caused 
 by the passage of the vortices over or near to the place of ob- 
 servation. The action of these vortices is proved to be of vari- 
 able force, whether arising from atmospheric conditions, or due 
 to an increased activity of the ethereal medium throughout the 
 whole system, is at present immaterial. They do vary, and 
 sometimes the passage of a vortex will deflect the needle a 
 whole degree. At other times, there are magnetic storms ex- 
 tending over a great part of the earth's surface ; but there is 
 reason to suppose, that the extent of these storms has been 
 over estimated. Thus, on the 25th of September, 1841, a mag- 
 netic storm was observed in Toronto, and at the same time 
 there was one felt at the Cape of Good Hope. There is no 
 great mystery in this. If we suppose the axis of the central 
 vortex, for instance, to have passed Toronto in latitude 43 33' 
 north, in ordinary positions of the moon, in her orbit, the 
 southern portion of the axis would be in 33 or 34 south lati- 
 tude, and consequently would have passed near the Cape of 
 Good Hope on the same night. Now, we certainly could not 
 expect the northern portion of the vortex to be intensely active, 
 
138 MECHANICAL THEORY OF STOKMS. 
 
 without the southern portion being in the same state of acti- 
 vity. That this is the true explanation is proved by magnetic 
 storms in the same hemisphere being comparatively limited in 
 extent ; as, according to Gauss and Weber, magnetic storms 
 which were simultaneously felt from Sicily to Upsala, did not 
 extend from Upsala to Alten. Still it would not be wonderful 
 if they were felt over a vast area of thousands of miles as a con- 
 sequence of great disturbance in the elasticity of the ether in 
 the terral vortex ; as the solid earth must be permeable to all its 
 motions, and thus be explicable on the general principles we 
 have advanced. 
 
 But besides these variations which we have mentioned, there 
 are changes steadily going on, by which the isodynamic, iso- 
 gonic and isoclinic lines are permanently displaced on the sur- 
 face of our planet. These must be attributed to changes of 
 temperature in the interior of the globe, and to the direction in 
 the progress of subterranean fires, which it may also be expected 
 will change the isogeothermal lines. But there are changes, 
 which although of long period, are yet periodic, one of which 
 is obviously due to the revolution of the lunar nodes in eighteen 
 and a half years, and the revolution of the apogee in nine 
 years. The first is continually changing the obliquity of the 
 axis of the vortex, and they both tend to limit the vortices in 
 their extreme latitudes ; but the planet Jupiter has an indirect 
 influence, which is probably equal, if not greater, than the 
 action of the moon, in changing the magnetic declination. 
 
 From the investigations of Lamont, it would appear, that 
 the period of the variations of magnetic declination is about 
 10 years, while, more recently, R. Wolfe has suggested the 
 connection between this variation and the solar spots, and 
 assigns a period of 11.11 years, and remarks, that it "corre- 
 sponds more exactly with the variations in magnetic declination 
 than the period of 10| years established by Lamont. The 
 magnetic variations accompany the solar spots, not only in 
 
MECHANICAL THEOEY OF STOEMS. 139 
 
 their regular changes, but even in their minor irregularities : 
 this latter fact is itself sufficient to prove definitely the import- 
 ant relations between them."* 
 
 As the planet Jupiter exerts the greatest influence on the 
 sun, in forcing the centre from the mechanical centre of the 
 system, the longitude of the sun will in a great measure depend 
 on the position of this planet; and, in consequence, the sun 
 will generally revolve around this centre in a period nearly 
 equal to the period of Jupiter. The sidereal period of Jupiter 
 is about twelve years, but the action of the other planets tend 
 to shorten this period (at least, that has been the effect for the 
 last twenty or thirty years), and bring it nearly to the period 
 assigned by M. Wolfe to the variations in the magnetic declin- 
 ations. As this has its influence on the radial stream, and the 
 radial stream on the declination, we see at once the connection 
 between them. When we come to a consideration of the solar 
 spots, we shall exhibit this influence more fully. 
 
 AURORA BOREALIS. 
 
 Let us now examine another phenomenon. The Aurora 
 Borealis has been generally considered to be in some way con- 
 nected with the magnetism of the earth, and with the position 
 of the magnetic pole. It is certain that the appearance of this 
 meteor does affect the needle in a way not to be mistaken, and 
 (although not invariably) the vertex of the luminous arch will 
 usually conform to the magnetic meridian. Yet (and this is 
 worthy of attention), the observations made in the North Polar 
 Expeditions! " appear to prove, that in the immediate vicinity 
 of the magnetic pole the development of light is not in the 
 least degree more intense or frequent than at some distance 
 from it." In fact, as the American magnetic pole is, as stated, 
 in latitude 73, the central vortex will seldom reach so high, 
 
 * Sillimau's Journal for March and April, 1853. 
 f Humboldt, Cosmos, p. 193, London eA 
 
140 MECHANICAL THEOEY OF STOEMS. 
 
 and, consequently, the aurora ought at such times to be more 
 frequent in a lower latitude. In a late work by M. de la Rive, 
 this gentleman expresses the opinion, that the cause of the 
 aurora is not due to a radiation of polar magnetism, but to a 
 purely electrical action.* His explanation, however, is not so 
 satisfactory as his opinion. Now, we have examined numerous 
 cases of auroral displays, and never yet found one which could 
 not be legitimately referred to the action of ethereal vortices. 
 Generally, the aurora will not be visible, when the upper sur- 
 face of the atmosphere of that latitude in which the vortex is 
 known to be (reckoning in the direction of the magnetic 
 meridian) is below the horizon, which shows that the brightest 
 portion is in the atmosphere. In latitude 41 even, it may 
 show itself when the vortex is three days north, more frequently 
 when one or two days north; but when the vortex passes 
 centrally, or south, it rarely is seen, and this is the only diffi- 
 culty in explaining it by the theory. But, when we reflect that 
 the ether shoots out in straight lines, and at an angle corre- 
 sponding to the magnetic dip, we are at no loss to perceive the 
 reason of this. If each minute line composing the light were 
 seen endwise, it would be invisible ; if there were millions such 
 in the same position, they could add nothing to the general 
 effect ; but, when viewed sideways, the case would be different, 
 there would be a continued reduplication of ray upon ray, until 
 in the range of some hundreds of miles an effect might be 
 produced amounting to any degree of intensity on record. 
 Now, this is the case when the aurora is immediately overhead, 
 it will be invisible to those below, but may be seen by persons 
 a hundred miles south ; so, also, when it is to the south, it is too 
 oblique to the line of vision to be seen, especially as all the 
 rays to the northward of the observer can contribute nothing 
 to increase the effect. That it is of the nature of rays very 
 much diffused, can hardly be doubted ; and, therefore, if only 
 
 * See Silliman's Journal for September, 1853. 
 
MECHANICAL THEORY OF STORMS. 141 
 
 of a few miles in depth, its impressions are too faint to be 
 sensible. By referring to the record of the weather in the 
 second section of this work, an auroral display will be found on 
 July 12th, the central vortex having passed a little to the 
 northward the same evening, and the next day passing south 
 descending. On that occasion the author saw an inclined 
 column, in profile, due east, and between himself and a line of 
 bluffs and timber, about eight miles distant ; and, he has not 
 any doubt, that the mass of rays began where he stood. As 
 in a shower, every drop, passing through a conical surface, whose 
 axis passes through the sun and through the eye, contributes 
 to form the apparently distant rainbow. 
 
 The altitude of this meteor has been much exaggerated, 
 especially of those rings or luminous arches, which are often 
 detached completely from the luminous bank. On the 24th of 
 May, a bright aurora was visible at Ottawa, but the author's 
 attention was engrossed by the most brilliant arch of light he 
 had ever seen. It was all the time south of the zenith, and 
 had no visible connection with the aurora north. At 9 hours, 
 59 minutes, 30 seconds mean solar time, Arcturus was in the 
 exact centre of the band, at which time it was very bright, and 
 full 7 wide. At the same time, Prof. G. W. Wheeler observed 
 the aurora in Perryville, in the State of Missouri, only 1 of 
 longitude to the westward, but did not see the arch.* The 
 difference of latitude between the two places being 3 36', and 
 the weather, as he states, clear and still, there is only one reason 
 why he did not see the arch : it must have been too low, and 
 had become merged in the bank of light. At the time men- 
 tioned, the altitude of Arcturus was 68 30', and, as Prof. 
 Wheeler assigns only 10 as the altitude of the bank, the 
 maximum elevation of the arch, on the supposition of its com- 
 posing a part of the bank, was 43 miles. At Perryville, the 
 bank and streamers had disappeared at 10 o'clock. At Ottawa, 
 
 *See Silliman's Journal for September, 1853. 
 
142 MECHANICAL THEORY OF STORMS. 
 
 the arch or bow disappeared at 10 h. 5 m., differing only the 
 fraction of a minute from the time at Perryville ; but, the bank 
 was still visible, but low and faint, the greatest altitude having 
 been over 30. To show the rapid fluctuations in width and 
 position of this bow, we will add a few of the minutes taken at 
 the time with great care, in hopes some other observer had 
 been equally precise. When first seen, there were three 
 luminous patches, or elongated clouds of light : one in Leo, one 
 in Bootes, and another in Ophinchus, all in line. This was 
 about 9 h. 15 m. The times following are correct to 30 
 seconds : 
 
 9h. 42m. 30s. Bow complete; south edge 2 north of Arc- 
 
 turus. 
 9 45 30 Northern edge diffuse south ; edge bright, and 
 
 well defined; 10 wide in zenith; north 
 
 edge on Alphacca. 
 9 47 30 South edge 5 north of Arcturus ; north edge 
 
 close to Cor. Caroli. 
 9 53 30 Eastern half composed of four detached bands 
 
 shingling over each other. 
 
 9 58 30 Arcturus on south ; bow narrower. 
 9 59 30 Arcturus in the middle of the band; very 
 
 bright and regular in outline, and widest at 
 
 the zenith. 
 10 30 Arcturus on northern edge; north side better 
 
 defined than the southern. 
 
 102 Arcturus 1 north ; very bright. 
 
 10 2 30 Glamma and Delta Leonis, northern edge. 
 
 103 Regulus on southern age ; getting faint. 
 10 5 Fast fading away. 
 
 10 5 30 Scarcely visible; bank in north faint. 
 
 This aurora was due to the inner vortex ascending, whose period 
 
 was at this time 28 days. 
 
MECHANICAL THEOKY OF STOEMS. 143 
 
 There are several circumstances to be observed in this case. 
 The bow brightened and faded simultaneously with the aurora, 
 and respected the vertex of the auroral bank, being apparently 
 concentric with it. The bow, therefore, depends on the same 
 cause, but differs from the aurora in being limited to the sur- 
 face of the atmosphere in which the vortex has produced a 
 wave to the southward of its central path, as may be understood 
 by inspecting Fig. 2, Sec. 1, the figure representing the polar 
 current of the central vortex. On the 29th of May, 1840,* 
 the author saw a similar phenomenon, at the same time of 
 night, and passing over the same stars southward until it 
 reached within 5 of Jupiter and Saturn, to which it was 
 parallel. This atmospheric wave offers a greater resistance to 
 the passage of the ether : hence the light. On this account it 
 is, also, that when the passage of a vortex is attended by an 
 auroral display there will be no thunder-storm. There may be 
 an increase of wind ; but the atmosphere at such times is too 
 dry to make a violent storm, and there is a silent restoration 
 of the equilibrium, by the ether passing through the dry 
 atmosphere, without meeting any condensable vapor, and be- 
 coming luminous on account of the greater resistance of the 
 air when unmixed with vapor. We thus see also the connec- 
 tion between the aurora and the linear cirri, and we have a 
 triumphant explanation of the fact, that when the observe!' is 
 north of the northern limit of the vortices, he sees the aurora 
 to the south and not to the north ; for, to see it to the north- 
 ward, he would have to see it in the same latitude as it appears 
 in the south, and, consequently, have to see across twice the 
 complement of the latitude. We thus see, also, why the tem- 
 perature falls after an aurora ; for, the passage of electricity in 
 any shape, must have this effect on account of the great 
 specific caloric of this fluid. We see, also, why the aurora 
 should be more frequent where the magnetic intensity is great- 
 * This was the central vortex ascending. 
 
144 MECHANICAL THEORY OP STORMS. 
 
 est, and be consequently invisible at the equator, and why the 
 magnetic needle is so sensibly affected at the time of its occur- 
 rence. We may, perhaps, here be allowed to allude to another 
 phenomenon connected with terrestrial magnetism and elec- 
 tricity. 
 
 EARTHQUAKES. 
 
 The awful and destructive concussions which sometimes are 
 produced at great depths beneath the surface of the soil, would 
 seem to indicate that no force but that of electricity is adequate 
 to account for the almost instantaneous desolation of wide tracts 
 of the earth's surface. But we do not mean to say that the 
 action of the terral vortices, combined with the internal condi- 
 tions of our planet, is the only cause ; although it is far from 
 improbable that the same activity of the ether, which generates 
 through these vortices, the full fury of the hurricane in the 
 tropics, may be simultaneously accompanied by a subterranean 
 storm. And physicists are too rash to reject the evidence on 
 which the connection of the phenomena rests. 
 
 In the extract given by Colonel Reid, in his " Law of Storms," 
 from Sir George Rodney's official report of the great hurricane 
 of 1*780, it is stated, that, "Nothing but an earthquake could 
 have occasioned the foundations of the strongest buildings to 
 be rent ; and I am convinced that the violence of the wind must 
 have prevented the inhabitants from feeling the earthquake 
 which certainly attended the storm."* Again, in the Savannah- 
 la-Mar hurricane, which occurred the same year and month, the 
 Annual Register, published at Jamaica, states, that at the same 
 time, " a smart shock of an earthquake was felt." The general 
 serenity of equatorial regions is due to the fact that they are 
 beyond the limit of the vortices, as in Peru, where neither rain 
 nor lightning nor storm is ever seen. Thunder and rain, with- 
 out storms, however, are common in other tropical countries, 
 
 * Reid's Law of Storms, p. 350. 
 
MECHANICAL THEOEY OF STOKMS. 145 
 
 also out of the reach of the vortices. But even in those parts, 
 (as the Antilles,) lying in the track of these vortices, the weather 
 is not as frequently disturbed as in higher latitudes. The 
 storms of the Antilles, when they do occur, however, are fearful 
 beyond any conception, showing the presence of some cause, 
 auxiliary to the ordinary disturbing action of the vortices, 
 which, when simultaneously occurring, adds tremendously to 
 their force. 
 
 That earthquakes are preceded sometimes by a peculiar hazi- 
 ness and oppressiveness, similar to that which sometimes pre- 
 cedes a storm, is a current opinion in volcanic countries. And 
 Htimboldt, who doubts the connection, has to confess that sud- 
 den changes of w r eather have succeeded violent earthquakes, and 
 that " during the great earthquake of Cumana, he found the in- 
 clination of the needle was diminished 48'." He also mentions 
 the simultaneous occurrence of shocks, from earthquakes, and a 
 clap of thunder, and the agitation of the electrometer during the 
 earthquake, which lasted from the 2d of April to the 17th of 
 May, 1808; but concluding that "these indications presented 
 by clouds, by modifications of atmospheric electricity, or by 
 calms, cannot be regarded as generally or necessarily connected 
 with earthquakes, since in Peru, Canada, and Italy, earthquakes 
 are observed, along with the purest and clearest skies, and with 
 the freshest land and sea breezes. But if no meteorological 
 phenomena indicates the coming earthquake, either on the 
 morning of the shock or a few days previously, the influence of 
 certain periods of the year, (the vernal and autumnal equinoxes,) 
 the commencement of the rainy season in the tropics, after long 
 drought, cannot be overlooked, even though the genetic connec- 
 tion of meteorological processes, with those going on in the in- 
 terior of our globe, is still enveloped in obscurity."* 
 
 It is at the equinoxes that the earth changes her distances 
 from the sun most rapidly, and whether she is passing from her 
 
 * Humboldt, Cosmos, p. 203. 
 7 
 
146 MECHANICAL THEOKY OF STOEMS. 
 
 perihelion or from her aphelion, the density of the ether exter- 
 nally is changing in the subduplicate ratio of these distances, 
 and consequently at these times there will be the greatest dis- 
 turbance of the electric equilibrium. How far our views of the 
 internal structure of our globe, (considered along a diameter as 
 a solid crust, then a fused mass separated from the lower ocean 
 by another solid crust, and separated from a similar arrange- 
 ment on the opposite side by an interposed mass of water, per- 
 haps also possessing a solid nucleus,) may affect this question, 
 is difficult to say ; but that the agent is electric, appears highly 
 probable; and very recently it has been discovered, by M. 
 Ratio Menton, that a piece of iron, suspended by attraction to a 
 magnet, will fall on the approach of an earthquake ; thus indi- 
 cating that the power of the magnet is temporarily weakened 
 by the action of some disturbing force. 
 
SECTION FOURTH. 
 
 THE SOLAR SPOTS. 
 
 WE have yet many phenomena to investigate by the aid of 
 the theory, and we will develop them in that order which will 
 best exhibit their mutual dependence. The solar spots have 
 long troubled astronomers, and to this day no satisfactory solu- 
 tion of the question has been proposed ; but we shall not 
 examine theories. It is sufficient that we can explain them on 
 the same general principles that we have applied to terrestrial 
 phenomena. There can be but little doubt about the existence 
 of a solar atmosphere, and, reasoning from analogy, the con- 
 stituent elements of the sun must partake of the nature of other 
 planetary matter. That there are bodies in our system pos- 
 sessing the same elements as our earth, is proved by the 
 composition of meteoric masses, which, whether they are inde- 
 pendent bodies of the system, or fragments of an exploded 
 planet, or projected from lunar volcanoes, is of little conse- 
 quence ; they show that the same elements are distributed to 
 other bodies of the system, although not necessarily in the 
 same proportions. The gaseous matter of the sun's atmosphere 
 may, therefore, be safely considered as vapors condensable by 
 cold, and the formation of vortices over the surface of this 
 atmosphere, brings down the ether, and causes it to intermingle 
 with this atmosphere. But, from the immensely rapid motion 
 of the polar current of the solar vortex, this ether may be 
 
148 MECHANICAL THEORY OF STORMS. 
 
 considered to enter the atmosphere of the sun with the temper- 
 ature of space. 
 
 Sir John Herschel, in commenting on the theory of Mr. 
 Redfield before the British Association, convened at Newcastle 
 in 1838,* suggested an analogy to terrestrial hurricanes, from 
 a suspected rotation and progressive motion in these spots. 
 From their rapid formation, change of shape, and diameter, 
 this view is allowable, and, taken in conjunction with the action 
 of the ethereal currents, will account for all the phenomena. 
 The nucleus of the spot is dense, like the nucleus of a storm 
 on the earth, and surrounded by a penumbon precisely as our 
 storms are fringed with lighter clouds, permitting the light of 
 the sun to penetrate. And, it has been observed, that these 
 spots seem to follow one another in lines on the same parallel 
 of solar latitude (or nearly the same), exactly as we have de- 
 termined the action of the vortices on the surface of the earth 
 from observation. These spots are never found in very high 
 latitudes not much above 30 from the solar equator. If we 
 consider this equator to be but slightly inclined to the plane of 
 the vortex, this latitude would be the general position of the 
 lateral solar vortices, and, in fact, be confined principally to a 
 belt on each side of the equator, between 15 and 30 of solar 
 latitude, rather than at the equator itself. This, it is needless 
 to say, is actually the case. But, a more capital feature still 
 has been more recently brought to light by observation, although 
 previously familiar to the author, who, in endeavoring to verify 
 the theory, seriously injured his sight, by observing with inade- 
 quate instrumental means. This is the periodicity of the spots. 
 
 We have already observed, that there is reason to suppose 
 that the action of the inner vortex of the earth is probably 
 greater than that of the outer vortex, on account of the con- 
 flicting currents by which it is caused. And the full develop- 
 ment of this vortex requires, that the central vortex or 
 * Silliman's Journal, vol. xxxv., page 283. 
 
MECHANICAL THEOEY OF STORMS. 149 
 
 mechanical axis of the system shall be nearly tangential to the 
 surface. In this position, the action of the central vortex is 
 itself at a maximum ; and, when the planets of the system are 
 so arranged as to produce this result, we may expect the 
 greatest number of spots. If the axis or central vortex ap- 
 proaches to coincidence with the axis of the sun, the lateral 
 vortices disappear, and the central vortex being then perpen- 
 dicular to the surface, is rendered ineffective. Under these 
 circumstances, there will be no spots on the sun's disc. When, 
 on the other hand, all the planets conspire at the same side to 
 force the sun out from the mechanical centre of the system, the 
 surface is too distant to be acted on by the central vortex, and 
 the lateral vortices are also thrown clear of the sun's surface, on 
 account of the greater velocity of the parts of the vortex, in 
 sweeping past the body of the sun. In this case, there will be 
 but few spots. The case in which the axis of the vortex coin- 
 cides with the axis of the sun, is much more transient than the 
 first position, and hence, although the interval between the 
 maxima will be tolerably uniform, there will be an irregularity 
 between a particular maximum, and the preceding and subse- 
 quent minimum. 
 
 The following table exhibits the solar spots, as determined by 
 Schwabe, of Dessau : 
 
 Year of observation. 
 
 Groups of spots observed. 
 
 Number of days. 
 
 1826 . . 
 
 ... 118 ... 
 
 . . 277 
 
 1827 . . 
 
 ... 161 ... 
 
 . . 273 
 
 1828 . . 
 
 ... 225 ... 
 
 . . 282 
 
 1829 . . 
 
 ... 199 ... 
 
 . . 244 
 
 1830 . . 
 
 ... 190 ... 
 
 . . 217 
 
 1831 . . 
 
 ... 149 ... 
 
 . . 239 
 
 1832 . . 
 
 ... 84 ... 
 
 . . 270 
 
 1833 . . 
 
 . . 33 ... 
 
 . . 267 
 
 1834 . . 
 
 ... 51 ... 
 
 . . 273 
 
 1835 
 
 m 
 
 244 
 
150 MECHANICAL THEORY OF STORMS. 
 
 Year of observation. Groups of spots observed. Number of days. 
 
 1836 272 200 
 
 1837 333 168 
 
 1338 282 202 
 
 1839 162 205 
 
 1840 152 263 
 
 1841 102 283 
 
 1842 68 307 
 
 1843 ..... 34 324 
 
 Previous to the publication of this table, the author had in- 
 ferred the necessity of admitting the existence of another planet 
 in the solar system, from the phenomenon of which we are 
 speaking. He found a sufficient correspondence between the 
 minima of spots to confirm the explanation given by the 
 theory, and this was still more confirmed by the more exact de- 
 termination of Schwabe ; yet there was a little discrepancy in 
 the synchronous values of the ordinates, when the theory was 
 graphically compared with the table. Previous to the dis- 
 covery of Neptune, the theory corresponded much better than 
 afterwards, and as no doubt could be entertained that the 
 anomalous movements of Uranus were caused by an exterior 
 planet, he adopted the notion that there were two planets ex- 
 terior to Uranus, whose positions at the time were such, that their 
 mechanical effects on the system were about equal and contrary. 
 Consequently, when Neptune became known, the existence of 
 another planet seemed a conclusion necessary to adopt. Accord- 
 ingly, he calculated the heliocentric longitudes and true anom- 
 alies, and the values of radius vector, for all the planets during 
 the present century, but not having any planetary tables, he 
 contented himself with computing for the nearest degree of true 
 anomaly, and the nearest thousand miles of distance. Then by 
 a composition and resolution of all the forces, he deduced the 
 radius vector of the sun, and the longitude of his centre, for each 
 past year of the century. It was in view of a little outstanding 
 
MECHANICAL THEORY OF STORMS. 
 
 151 
 
 discrepancy in the times of the minima, as determined by theory 
 and observation, that he was induced to consider as almost cer- 
 tain the existence of a theoretical planet, whose longitude, in 
 1828, was about 90, and whose period is from the theory about 
 double that of Neptune. And for convenience of computation 
 and reference, he has been in the habit of symbolizing it by a 
 volcano. The following table of the radii vectores of the sun, 
 and the longitude of his centre, for the years designated in 
 Schwabe's table, is calculated from the following data for each 
 planet : 
 
 Planets. 
 * 
 * 
 fc 
 
 No. of spots in 
 Schwabe's table. 
 
 ToVj 
 
 ^O-flTO-Q- 
 
 3TO-0- 
 
 Mean distances. 
 
 Eccentricities. 
 
 Long, of 
 Perihelion. 
 
 494.800.000 
 
 . 0.0481 . 
 
 11 
 
 907.162.000 
 
 . 0.0561 . 
 
 89 
 
 1824.290.000 
 
 . 0.0166 . 
 
 167 
 
 2854.000.000 
 
 . 0.0088 . 
 
 
 
 4464.000.000 
 
 m t 
 
 
 Dates. 
 
 Rad. vector. 
 
 Sun's long. 
 
 Ordinates. 
 
 Jan. 1, 1826 
 
 528,000 
 
 320 
 
 + 84 
 
 " 1827 
 
 480,000 
 
 339 
 
 -f- 36 
 
 " 1828 
 
 432,000 
 
 352 
 
 12 
 
 " 1829 
 
 397,000 
 
 38 
 
 47 
 
 ' 1830 
 
 358,000 
 
 71 
 
 86 
 
 " 1831 
 
 324,000 
 
 104 
 
 120 
 
 " 1832 
 
 311,000 
 
 144 
 
 133 
 
 " 1833 
 
 300,000 
 
 183 
 
 144 
 
 " 1834 
 
 307,000 
 
 220 
 
 137 
 
 " 1835 
 
 338,000 
 
 263 
 
 106 
 
 " 1836 
 
 389,000 
 
 302 
 
 55 
 
 " 1837 
 
 419.000 
 
 337 
 
 + 25 
 
 " 1838 
 
 488,000 
 
 3 
 
 + 44 
 
 " 1839 
 
 551,000 
 
 29 
 
 -f 107 
 
 " 1840 
 
 632,000 
 
 51 
 
 4- 188 
 
 " 1841 
 
 680,000 
 
 80 
 
 4- 236 
 
 " 1842 
 
 730,000 
 
 105 
 
 4- 286 
 
 " 1843 
 
 766,000 
 
 128 
 
 4- 322 
 
 1844 
 
 783,000 
 
 152 
 
 4- 389 
 
 Max. 
 
 Min. 
 
 Max. 
 
 Miii 
 
 118 
 
 161 
 
 225 
 
 199 
 
 190 
 
 149 
 
 84 
 
 33 
 
 51 
 
 173 
 
 272 
 
 333 
 
 282 
 
 162 
 
 152 
 
 102 
 
 68 
 
 34 
 
 52 
 
 Max 
 
 Min. 
 
 Max. 
 
 Min. 
 
Jan. 1, 1845 
 
 772,000 
 
 174 
 
 + 328 
 
 " 1846 
 
 728,000 
 
 196 
 
 -j- 284 
 
 " 1847 
 
 660,000 
 
 218 
 
 -f 216 
 
 " 1848 
 
 563,000 
 
 240 
 
 -f- 119 
 
 " 1849 
 
 447,000 
 
 261 
 
 + 3 
 
 " 1850 
 
 309,000 
 
 283 
 
 135 
 
 " 1851 
 
 170,000 
 
 323 
 
 274 
 
 " 1852 
 
 53,000 
 
 41 
 
 391 
 
 " 1853 
 
 167,000 
 
 133 
 
 - 277 
 
 <; 1854 
 
 315,000 
 
 160 
 
 129 
 
 " 1855 
 
 475,000 
 
 183 
 
 + 31 
 
 " 1856 
 
 611,000 
 
 203 
 
 -f- 167 
 
 " 1857 
 
 720,000 
 
 225 
 
 -f 276 
 
 152 MECHANICAL THEORY OF STORMS. 
 
 Dates. Rad. vector. Sun's long. Ordinates. No. of spots in 
 
 Schwabe's table. 
 
 114 
 157 
 
 Observed. Max. 
 Max. 
 
 Min. 
 
 Max. 
 
 It is necessary to observe here, that the values of the num- 
 bers in Schwabe's table are the numbers for the whole year, 
 and, therefore, the 1st of July would have been a better date 
 for the comparison ; but, as the table was calculated before the 
 author was cognizant of the fact, and being somewhat tedious 
 to calculate, he has left it as it was, viz., for January 1st of each 
 year. Hence, the minimum for 1843 appears as pertaining to 
 1844. The number of spots ought to be inversely as the 
 ordinates approximately these last being derived from the 
 Radii Vectores minus, the semi-diameter of the sun = 444,000 
 miles. 
 
 In passing judgment on this relation, it must also be borne 
 in mind, that the recognized masses of the planets cannot be 
 the true masses, if the theory be true. Both sun and planets 
 are under-estimated, yet, as they are, probably, all to a certain 
 degree proportionally undervalued, it will not vitiate the above 
 calculation much. 
 
 The spots being considered as solar storms, they ought also 
 to vary in number at different times of the year, according to 
 the longitude of the earth and sun, and from their transient 
 character, and the slow rotation of the sun, they ought, ceteris 
 
MECHANICAL THEORY OF STORMS. 153 
 
 paribus, to be more . numerous when the producing vortex is 
 over a visible portion of the sun's surface. 
 
 The difficulty of reconciling the solar spots, and their period- 
 icity to any known principle of physics, ought to produce a 
 more tolerant spirit amongst the scientific for speculations even 
 which may afford the slightest promise of a solution, although 
 emanating from the humblest inquirer after truth. The hypo- 
 thesis of an undiscovered planet, exterior to Neptune, is of a 
 nature to startle the cautious timidity of many ; but, if the 
 general theory be true, this hypothesis becomes extremely prob- 
 able. We may not have located it exactly. There may be 
 even two such planets, whose joint effect shall be equivalent to 
 one in the position we have assigned. There may even be a 
 comet of great mass, capable of producing an effect on the 
 position of the sun's centre (although it follows from the theory 
 that comets have very little mass). Yet, in view of all these 
 suppositions, there can be but little doubt that the solar spots 
 are caused by the solar vortices, and these last made effective 
 on the sun by the positions of the great planets, and, therefore, 
 we have indicated a new method of determining the existence 
 and position of all the planets exterior to Neptune. On the 
 supposition that there is only one more in the system, from its 
 deduced distance and mass, it will appear only as a star of the 
 eleventh magnitude, and, consequently, will only be recogniza- 
 ble by its motion, which, at the greatest, will only be ten or 
 eleven seconds per day. 
 
 MASSES OF THE SUN AND PLANETS, 
 
 We have alluded to the fact of the radial stream of fche sun 
 necessarily diminishing the sun's power, and, consequently, 
 diminishing his apparent mass. The radial stream of all the 
 planets will do the same, so that each planet whose mass is 
 derived from the periodic times of the satellites, will also appear 
 ' 7* 
 
154 MECHANICAL THEORY OF STOEMS. 
 
 too small. But, there is also a great probability that some 
 modification must be made in the wording of the Newtonian 
 law. The experiments of Newton on the pendulum, with every 
 variety of substance, was sufficient justification to entitle him 
 to infer, that inertia was as the weight of matter universally. 
 But, there was one condition which could not be observed in 
 experimenting on these substances, viz., the difference of tem- 
 perature existing between the interior and surface of a planet. 
 
 We have already expressed the idea, that the cause of gravity 
 has no such mysterious origin as to transcend the power of man 
 to determine it. But that, on the contrary, we are taught by 
 every analogy around us, as well as by divine precept, to use 
 the visible things of creation as stepping stones to the attain- 
 ment of what is not so apparent. That we have the volume 
 of nature spread out in tempting characters, inviting us to read, 
 and,, assuredly, it is not so spread in mockery of man's limited 
 powers. As science advances, strange things, it is true, are 
 brought to light, but the more rational the queries we pro- 
 pound, in every case the more satisfactory are the answers. It 
 is only when man consults the oracle in irrational terms that 
 the response is ambiguous. Alchemy, with its unnatural trans- 
 mutations, has long since vanished before the increasing light. 
 Why should not attraction also ? Experience and experiment, 
 if men would only follow their indications, are consistently 
 enforcing the necessity of erasing these antiquated chimeras 
 from the book of knowledge ; and inculcating the great truth, 
 that the physical universe owes all its endless variety to differ- 
 ences in the form, size, and density of planetary atoms in 
 motion, according to simple mechanical principles. These, 
 combined with the existence of an all-pervading medium filling 
 space, between which and planetary matter no bond of union 
 subsists, other than that which arises from a continual inter- 
 change of motion, are the materials from which the gems of 
 nature are elaborated. But, simplicity of means is what phil- 
 
MECHANICAL THEOKY OF STOKMS. 155 
 
 osophy has ever been reluctant to admit, preferring rather the 
 occult and obscure. 
 
 If action be equal to reaction, and all nature be vibrating 
 with motion, these motions must necessarily interfere, and some 
 effect should be produced. A body radiating its motion on 
 every side into a physical medium, produces waves. These 
 waves are a mechanical effect, and the body parts with some of 
 its motion in producing them ; but, should another body be 
 placed in juxtaposition, having the same motion, the opposing 
 waves neutralize each other, and the bodies lose no motion 
 from their contiguous sides, and, therefore, the reaction from 
 the opposite sides acts as a propelling power, and the bodies 
 approach, or tend to approach each other. If one body be of 
 double the inertia, it moves only half as far as the first; then, 
 seeing that this atomic motion is radiated, the law of force 
 must be directly as the mass, and inversely as the squares of 
 the distances. There may be other atomic vibrations besides 
 those which we call light, heat, and chemical action, yet the 
 joint effect of all is infinitesimally small, when we disregard 
 the united attraction of all the atoms of which the earth is 
 composed. The attraction of the whole earth at the surface 
 causes bodies to fall 16 feet the first second of time; but, if 
 two spheres of ice of one foot diameter, were placed in an 
 infinite space, uninfluenced by other matter, and only 16 feet 
 apart, they would require nearly 10,000 years to fall together 
 by virtue of their mutual attraction. Our conceptions, or, 
 rather, our misconceptions, concerning the force of gravity, 
 arises from our forgetting that every pound of matter on the 
 earth contributes its share of the force which, in the aggregate, 
 is so powerful. Hence, the cause we have suggested, is fully 
 adequate to account for the phenomena. Whether the har- 
 mony of vibrations between two bodies may not have an 
 influence in determining the amount of interference, and, conse- 
 quently, produce some difference between the gravitating mass 
 
156 MECHANICAL THEOKY OF STOEMS. 
 
 and its inertia, is a question which, no doubt, will ultimately be 
 solved ; but this harmony of vibrations must depend, in some 
 degree, on the atomic weight, temperature, and intensity of 
 atomic motion. 
 
 That a part of the mass of the earth is latent, may be inferred 
 from certain considerations : 1st, from the discrepancies existing 
 in the results obtained for the earth's compression by the 
 pendulum and by actual measurement ; and, 2d, from the 
 irregularity of that compression in particular latitudes and 
 longitudes. The same may also be deduced from the different 
 values of the moon's mass as derived from different pheno- 
 mena, dependent on the law of gravitation. Astronomers have 
 hitherto covered themselves with the very convenient shield of 
 errors of observation ; but, the perfection of modern instru- 
 ments now demand a better account of all outstanding discrep- 
 ancies. The world requires it of them. 
 
 The mass of the moon comes out much greater by our 
 theory than nutation gives. The mass deduced from the theory 
 is only dependent on the relative inertias of the earth and 
 moon. That given by nutation depends on gravity. If, then, 
 a part of the mass be latent, nutation will give too small a 
 value. But, in addition to this, we are justified in doubting 
 the strict wording of the Newtonian law, deriving our authority 
 from the very foundation stone of the Newtonian theory. 
 
 It is well known that Newton suspected that the moon was 
 retained in her orbit by the same force which is usually called 
 weight upon the surface, sixteen years before the fact was 
 confirmed, by finding a correspondence in the fall of the moon 
 and the fall of bodies on the earth. Usually, in all elementary 
 works, this problem is considered accurately solved. Having 
 formed a different idea of the mechanism of nature, this fact 
 presented itself as a barrier beyond which it was impossible to 
 pass, until suspicions, derived from other sources, induced the 
 author to inquire : Whether the phenomenon did exactly 
 
MECHANICAL THEOKY OF STORMS. 157 
 
 accord with the theory ? We are aware that it is easy to place 
 the moon at such a distance, that the result shall strictly cor- 
 respond with the fact ; but, from the parallax, as derived from 
 observation (and if this cannot be depended on certainly, no 
 magnitudes in astronomy can), we find, that the moon does not 
 fall from the tangent of her orbit, as much as the theory re- 
 quires. As this is of vital importance to the integrity of the 
 theory we are advocating, we have made the computation on 
 Newton's own data, except such as were necessarily inaccurate 
 at the time he wrote; and we have done it arithmetically, 
 without logarithmic tables, that, if possible, no error should 
 creep in to vitiate the result. We take the moon's elements 
 from no less an authority than Sir John Herschel, as well as 
 the value of the earth's diameter. 
 
 Mass of the moon ^ 
 
 Mean distance in equatorial radii . 59.96435 
 Sidereal period in seconds . . . 2360591 
 
 The vibrations of the pendulum give the force of gravity at 
 the surface of the earth, and it is found to vary in different 
 latitudes. The intensity in any place being as the squares of 
 the number of vibrations in a given time. This inequality de- 
 pends on the centrifugal force of rotation, and on the spheroi- 
 dal figure of the earth due to that rotation. At the equator 
 the fall of a heavy body is found to be 16.045223 feet, per 
 second, and in that latitude the squares of whose sine is , it is 
 16.0697 feet. The effect in this last-named latitude is the same 
 as if the earth were a perfect sphere. This does not, however, 
 express the whole force of gravity, as the rotation of the earth 
 causes a centrifugal tendency which is a maximum at the 
 equator, and there amounts to -%\-g of the whole gravitat- 
 ing force. In other latitudes it is diminished in the ratio of 
 the squares of the cosines of the latitude ; it therefore becomes 
 T T in that latitude the square of whose sine is -J. Hence 
 
158 MECHANICAL THEORY OF STORMS. 
 
 the fall per second becomes 16.1067 feet for the true gravitat- 
 ing force of the earth, or for that force which retains the moon 
 in her orbit. 
 
 The moon's mean distance is 59.96435 equatorial radii of 
 the earth, which radius is, according to Sir John Herschell, 
 20.923.713 feet. Her mean distance as derived from the par- 
 rallax is not to be considered the radius vector of the orbit, in- 
 asmuch as the earth also describes a small orbit around the 
 common centre of gravity of the earth and moon ; neither is 
 radius vector to be considered as her distance from this com- 
 mon centre ; for the attracting power is in the centre of the 
 earth, ^ut the mean distance of the moon moving around a 
 movable centre, is to the same mean distance when the centre 
 of attraction is fixed, as the sum of the masses of the two bodies, 
 to the first of two mean proportionals between this sum and 
 the largest of the two bodies inversely. (Vid Prin. Prop. 60 
 Lib. Prim.) The ratio of the masses being as above 80 to 1 
 the mean proportional sought is 80.666 and in this ratio must 
 the moon's mean distance be diminished to get the force of 
 gravity at the moon. Therefore as 81 is to 80.666, so is 
 59.96435 to 59.71657 for the moon's distance in equatorial 
 radii of the earth. Multiply this last by 20.923,713 to bring 
 the semi-diameter of the lunar orbit into feet 1.249.492.373, 
 and this by 6.283185, the ratio of the circumference to the 
 radius, gives 7.850.791.736 feet, for the mean circumference 
 of the lunar orbit. 
 
 Further, the mean sidereal period of the moon is 2360591 
 seconds and the jsJ-ksJi'^ P art f 7.850.791.736 is the 
 arc the moon describes in one second = 3325.77381 feet, the 
 square of which divided by the diameter of the orbit, gives the 
 fall of the moon from the tangent or versed size of that arc. 
 
 = "0^-36876644 = 0.004426106 feet. 
 
 2498984746 
 This fraction is, however, too small, as the ablatitious action 
 
MECHANICAL THEORY OF STOKMS. 159 
 
 of the sun diminishes the attraction of the earth on the moon, 
 in the ratio of I78f to l77ff. So that we must increase the 
 fall of the moon in the ratio of 711 to 715, and hence the true 
 fall of the moon from the tangent of her orbit becomes 0.00451 
 feet per second. 
 
 We have found the fall of a body at the surface of the earth, 
 considered as a sphere, 16.1067 feet per second, and the force 
 of gravity diminishes as the squares of the distances increases. 
 The polar diameter of the earth is set down as 7899.170 miles, 
 and the equatorial diameter 7925.648 miles; therefore, the 
 mean diameter is 7916.189 miles.* So that, reckoning in 
 mean radii of the earth, the moon's distance is 59.787925, 
 which squared, is equal to 3574.595975805625. At one mean 
 radius distance, that is, at the surface, the force of gravity, or 
 fall per second, is as above, 16.1067 feet. Divide this by the 
 
 1 f\ 1 C\ f\ *7 
 
 square of the distance, it is 3574 . 59597580a ^ = 0.0045058 
 
 feet for the force of gravity at the moon. But, from the pre- 
 ceding calculation, it appears, that the moon only falls 
 0.0044510 feet in a second, showing a deficiency of T ^d 
 part of the principal force that retains the moon in her orbit, 
 being more than double the whole disturbing power of the 
 sun, which is only y-y^th of the earth's gravity at the moon ; 
 yet, on this y^a-th depends the revolution of the lunar apogee 
 and nodes, and all those variations which clothe the lunar 
 theory with such formidable difficulties. The moon's mass 
 cannot be less than T ^, and if we consider it greater, s it no 
 doubt is, the results obtained will be still more discrepant. 
 Much of this discrepancy is owing to the expulsive power of 
 the radial stream of the terral vortex ; yet, it may be suspected 
 that the effect is too great to be attributed to this, and, for this 
 
 * The real diameter of the earth in that latitude, whose sine is one- 
 third, is a little greater than this ; but the true mean is more favorable 
 for the Newtonian law. 
 
160 MECHANICAL THEORY OF STOEMS. 
 
 reason, we have suggested that the fused matter of the moon's 
 centre may not gravitate with the same force as the exterior 
 parts, and thus contribute to increase the discrepancy. 
 
 As there must be a similar effect produced by the radial 
 stream -of every vortex, the masses of all the planets will appear 
 too small, as derived from their gravitating force ; and the in- 
 ertia of the sun will also be greater than his apparent mass ; 
 and if, m addition to this, there be a portion of these masses 
 latent, we shall have an ample explanation of the connection 
 between the planetary densities and distances. We must there- 
 fore inquire what is the particular law of force which governs 
 the radial stream of the solar vortex. It will be necessary to 
 enter into this question a little more in detail than our limits 
 will justify ; but it is the resisting influence of the ether, and 
 its consequences, which will appear to present a vulnerable 
 point in the present theory, and to be incompatible with the 
 perfection of astronomical science. 
 
 LAW OF DENSITY IN SOLAR VORTEX. 
 
 Reverting to the dynamical principle, that the product of 
 every particle of matter in a fluid vortex, moving around a 
 given axis, by its distance from the centre and angular velocity, 
 must ever be a constant quantity, it follows that if the ethereal 
 medium be uniformly dense, the periodic times of the parts of 
 the vortex will be directly as the distances from the centre or 
 axis ; but the angular velocities being inversely as the times, the 
 absolute velocities will be equal at all distances from the centre. 
 
 Newton, in examining the doctrine of the Cartesian vortices, 
 supposes the case of a globe in motion, gradually communi- 
 cating that motion to the surrounding fluid, and finds that the 
 periodic times will be in the duplicate ratio of the distances from 
 the centre of the globe. He and his successors have always 
 assumed that it was impossible for the principle of gravity to 
 
MECHANICAL THEORY OF STORMS. 161 
 
 be true, and a Cartesian plenum also ; consequently, the ques- 
 tion has not been fairly treated. It is true that Descartes 
 sought to explain the motions of the planets, by the mechanical 
 action of a fluid vortex solely ; and to Newton belongs the 
 glorious honor of determining the existence of a centripetal force, 
 competent to explain these motions mathematically, (but not 
 physically,) and rashly rejected an intelligible principle for a 
 miraculous virtue. If our theory be true, the visible creation 
 depends on the existence of both working together in harmony, 
 and that a physical medium is absolutely necessary to the ex- 
 istence of gravitation. 
 
 If space be filled with a fluid medium, anology would teach 
 us that it is in motion, and that there must be inequalities in 
 the direction and velocity of that motion, and consequently there 
 must be vortices. And if we ascend into the history of the past, 
 we shall find ample testimony that the planetary matter now 
 composing the members of the solar system, was once one vast 
 nebulous cloud of atoms, partaking of the vorticose motion of 
 the fluid involving them. Whether the gradual accumulation 
 of these atoms round a central nucleus from the surrounding 
 space, and thus having their tangential motion of translation 
 converted into vorticose motion, first produced the vortex in the 
 ether ; or whether the vortex had previously existed, in con- 
 sequence of conflicting currents in the ether, and the scattered 
 atoms of space were drawn into the vortex by the polar cur- 
 rent, thus forming a nucleus at the centre, as a necessary result 
 of the eddy which would obtain there, is of little consequence. 
 The ultimate result would be the same. A nucleus, once formed, 
 would give rise to a central force, tending more and more to 
 counteract the centripulsive power of the radial stream ; and in 
 consequence of this continually increasing central power, the 
 heaviest atoms would be best enabled to withstand the radial 
 stream, while the lighter atoms might be carried away to the 
 outer boundaries of the vortex, to congregate at leisure, and, 
 
162 MECHANICAL THEOEY OF STOKMS. 
 
 after the lapse of a thousand years, to again face the radial 
 stream in a more condensed mass, and to force a passage to the 
 very centre of the vortex, in an almost parabolic curve. That 
 space is filled with isolated atoms or planetary dust, is rendered 
 very probable by a fact discovered by Struve, that there is a 
 gradual extinction in the light of the stars, amounting to a loss 
 of T i T of the whole, in the distance which separates Sirius from 
 the sun. According to Struve, this can be accounted for, " by 
 admitting as very probable that space is filled with an ether, 
 capable of intercepting in some degree the light." Is it not as 
 probable that this extinction is due to planetary dust, scattered 
 through the pure ether, whose vibrations convey the light, the 
 material atoms of future worlds, the debris of dilapidated 
 comets ? Does not the Scripture teach the same thing, in as- 
 serting that the heavens are not clean ? 
 
 The theory of vortices has had many staunch supporters 
 amongst those deeply versed in the science of the schools. The 
 Bernoullis proposed several ingenious hypothesis, to free the 
 Cartesian system from the objections urged against it, viz. : that 
 the velocities of the planets, in accordance with the three great 
 laws of Kepler, cannot be made to correspond with the motion 
 of a fluid vortex ; but they, and all others, gave the vantage 
 ground to the defenders of the Newtonian philosophy, by seek- 
 ing to refer the principle of gravitation to conditions dependent 
 on the density and vorticose motion of the ether. When we 
 admit that the ether is imponderable and yet material, and 
 planetary matter subject to the law of gravitation, the objections 
 urged against the theory of vortices become comparatively 
 trivial, and we shall not stop to refute them, but proceed with 
 the investigation, and consider that the ether is the original 
 source of the planetary motions and arrangements. 
 
 On the supposition that the ether is uniformly dense, we have 
 shown that the periodic times will be directly as the distances 
 from the axis. If the density be inversely as the distances, the 
 
MECHANICAL THEORY OF STOKMS. 163 
 
 periodic times will be equal. If the density be inversely as the 
 square roots of the distances, the times will be directly in the 
 same ratio. The celebrated J. Bernoulli assumed this last 
 ratio ; but seeking the source of motion in the rotating central 
 globe, he was led into a hypothesis at variance with anology. 
 The ellipticity of the orbit, according to this view, was caused 
 by the planet oscillating about a mean position, sinking first 
 into the dense ether, then, on account of superior buoyancy, 
 rising into too light a medium. Even if no other objection 
 could be urged to this view, the difficulty of explaining why the 
 ether should be denser near the sun, would still remain. We 
 might make other suppositions ; for whatever ratio of the dis- 
 tances we assume for the density of the medium, the periodic 
 times will be compounded of those distances and the assumed 
 ratio. Seeing, therefore, that the periodic times of the planets 
 observe the direct ses-plicate ratio of the distances, and that it 
 is consonant to all analogy to suppose the contiguous parts of 
 the vortex to have the same ratio, we find that the density of 
 the ethereal medium in the solar vortex, is directly as the square 
 roots of the distances from the axis. 
 
 Against this view, it may be urged that if the inertia of the 
 medium is so small, as is supposed, and its elasticity so great, 
 there can be no condensation by centrifugal force of rotation. 
 It is true that when we say the ether is condensed by this force, 
 we speak incorrectly. If in an infinite space of imponderable 
 fluid a vortex is generated, the central parts are rarefied, and 
 the exterior parts are unchanged. But in all finite vortices there 
 must be a limit, outside of which the motion is null, or perhaps 
 contrary. In this case there may be a cylindrical ring, where 
 the medium will be somewhat denser than outside. Just as in 
 water, every little vortex is surrounded by a circular wave, vis- 
 ible by reflection. As the density of the planet Neptune appears, 
 from present indications, to be a little denser than Uranus, and 
 Uranus is denser than Saturn, we may conceive that there is 
 
164 MECHANICAL THEORY OF STORMS. 
 
 such a wave in the solar vortex, near which rides this last mag- 
 nificent planet, whose ring would thus be an appropriate 
 emblem of the peculiar position occupied by Saturn. This may 
 be the case, although the probability is, that the density of 
 Saturn is much greater than it appears, as we shall presently 
 explain. 
 
 In order to show that there is nothing extravagant in the 
 supposition of the density of the ether being directly as the 
 square roots of the distances from the axis, we will take a fluid 
 whose law of density is known, and calculate the effect of the 
 centrifugal force, considered as a compressing power. Let us 
 assume our atmosphere to be 47 miles high, and the com- 
 pressing power of the earth's gravity to be 289 times greater 
 than the centrifugal force of the equator, and the periodic time 
 of rotation necessary to give a centrifugal force at the equator 
 equal to the gravitating force to be 83 minutes. Now, consid- 
 ering the gravitating force to be uniform, from the surface of 
 the earth upwards, and knowing from observation that at 
 18,000 feet above the surface, the density of the air is only -J, 
 it follows, (in accordance with the principle that the density is 
 as the compressing force,) that at 43 miles high, or 18,000 
 feet below the surface of the atmosphere, the density is only 
 __i__ part of the density at the surface of the earth. Let us 
 take this density as being near the limit of expansion, and con- 
 ceive a hollow tube, reaching from the sun to the orbit of Nep- 
 tune, and that this end of the tube is closed, and the end at the 
 sun communicates with an inexhaustible reservoir of such an 
 attenuated gas as composes the upper-layer of our atmosphere ; 
 and further, that the tube is infinitely strong to resist pressure, 
 without offering resistance to the passage of the air within the 
 tube ; then we say, that, if the air within the tube be continually 
 acted on by a force equal to the mean centrifugal force of the 
 solar vortex, reckoning from the sun to the orbit of Neptune, 
 the density of the air at that extremity of the tube, would be 
 
MECHANICAL THEOKY OF STORMS. 165 
 
 greater than the density of a fluid formed by the compression 
 of the ocean into one single drop. For the centrifugal force of 
 the vortex at 2,300,000 miles from the centre of the sun, is 
 equal to gravity at the surface of the earth, and taking the 
 mean centrifugal force of the whole vortex as one-millionth of 
 this last force ; so that at 3,500,000 miles from the surface of 
 the sun, the density of the air in the tube (supposing it ob- 
 structed at that distance) would be double the density of the 
 attenuated air in the reservoir. And the air at the extremity 
 of the tube reaching to the orbit of Neptune, would be as much 
 denser than the air we breathe, as a number expressed by 273 
 with 239 ciphers annexed, is greater than unity. This is on 
 the supposition of infinite compressibility. Now, in the solar 
 vortex there is no physical barrier to oppose the passage of the 
 ether from the centre to the circumference, and the density of 
 the ethereal ocean must be considered uniform, except in the 
 interior of the stellar vortices, where it will be rarefied ; and the 
 rarefaction will depend on the centrifugal force and the length 
 of the axis of the vortex. If this axis be very long, and the 
 centrifugal velocity very great, the polar influx will not be suf- 
 ficient, and the central parts will be rarefied. We see, there- 
 fore, no reason why the density of the ether may not be three 
 times greater at Saturn than at the earth, or as the square roots 
 of the distances directly. 
 
 BODES' LAW OF PLANETARY DISTANCES. 
 
 Thus, in the solar vortex, there will be two polar currents 
 meeting at the sun, and thence being deflected at right angles, 
 in planes parallel to the central plane of the vortex, and 
 strongest in that central plane. The velocity of expansion 
 must, therefore, diminish from the divergence of the radii, as 
 the distances increase ; but in advancing along these planes, the 
 ether of the vortex is continually getting more dense, which 
 
166 MECHANICAL THEOKY OF STORMS. 
 
 operates by absorption or condensation on the radial stream ; 
 so that the velocity is still more diminished, and this in the 
 ratio of the square roots of the distances directly. By com- 
 bining these two ratios, we find that the velocity of the radial 
 stream will be in the ses-plicate ratio of the distances inversely. 
 But the force of this stream is not as the velocity, but as the 
 square of the velocity. The force of the radial stream is con- 
 sequently as the cubes of the distances inversely, from the axis 
 of the vortex, reckoned in the same plane. If the ether, how- 
 ever, loses in velocity by the increasing density of the medium, 
 it becomes also more dense ; therefore the true force of the 
 radial stream will be as its density and the square of its velo- 
 city, or directly as the square roots of the distances, and in- 
 versely as the cubes of the distances, or as the 2.5 power of the 
 distances inversely. 
 
 If we consider the central plane of the vortex as coincident 
 with the plane of the ecliptic, and the planetary orbits, also, in 
 the same plane ; and had the force of the radial stream been 
 inversely as the square of the distances, there could be no 
 disturbance produced by the action of the radial stream. It 
 would only counteract the gravitation of the central body by a 
 certain amount, and would be exactly proportioned at all 
 distances. As it is, there is an outstanding force as a disturbing 
 force, which is in the inverse ratio of the square roots of the 
 distances from the sun ; and to this is, no doubt, owing, in part, 
 the fact, that the planetary distances are arranged in the inverse 
 order of their densities. 
 
 Suppose two planets to have the same diameter to be placed 
 in the same orbit, they will only be in equilibrium when their 
 densities are equal. If their densities are unequal, the lighter 
 planet will continually enlarge its orbit, until the force of the 
 radial stream becomes proportional to the planets resisting 
 energy. This, however, is on the hypothesis that the planets 
 are not permeable by the radial stream, which, perhaps, is more 
 
MECHANICAL THEORY OF STORMS. 167 
 
 consistent with analogy than with the reality. And it is more 
 probable that the mean atomic weight of a planet's elements 
 tends more to fix the position of equilibrium for each. Under 
 the law of gravity, a planet may revolve at any distance from 
 the sun, but if we superadd a centripulsive force, whose law is 
 not that of gravity, but yet in some inverse ratio of the dis- 
 tances, and this force acts only superficially, it would be possible 
 to make up in volume what is wanted in density, and a lighter 
 planet might thus be found occupying the position of a dense 
 planet. So the planet Jupiter, respecting only his resisting 
 surface, is better able to withstand the force of the radial stream 
 at the earth than the earth itself. To understand this, it is 
 necessary to bear in mind, that, as far as planetary matter is 
 concerned, the earth could revolve in Jupiter's orbit in the same 
 periodic time as -Jupiter, under the law of gravity; but that, 
 in reality, the whole of the gravitating force is not effective, 
 and that the equilibrium of a planet is due to a nice balance of 
 interfering forces arising from the planet's physical peculiarities. 
 As in a refracting body, the density of the ether may be con- 
 sidered inversely as the refraction, and this as the atomic weight 
 of the refracting material, so, also, in a planet, the density of 
 the ether will be inversely in the same ratio of the density of 
 the matter approximately. Hence, the density of the ether 
 within the planet Jupiter is greater than that within the earth ; 
 and, on this ethereal matter, the sun has no power to restrain it 
 in its orbit, so that the centrifugal momentum of Jupiter would 
 be relatively greater than the centrifugal momentum of the 
 earth, were it also in Jupiter's orbit with the same periodic 
 time. Hence, to make an equilibrium, the earth should revolve 
 in a medium of less density, that there may be the same pro- 
 portion between the external ether, and the ether within the 
 earth, as there is between the ether around Jupiter and the 
 ether within ; so that the centrifugal tendency of the dense 
 ether at Jupiter shall counteract the greater momentum of the 
 
168 MECHANICAL THEOEY OF STORMS. 
 
 dense ether within Jupiter ; or, that the lack of centrifugal 
 momentum in the earth should be rendered equal to the cen- 
 trifugal momentum of Jupiter, by the deficiency of the centri- 
 fugal momentum of the ether at the distance of the earth. 
 
 If, then, the diameters of all the planets were the same (sup- 
 posing the ether to act only superficially), the densities would 
 be as the distances inversely ;* for the force due to the radial 
 stream is as the square roots of the distance inversely, and the 
 force due to the momentum, if the density of the ether within 
 a planet be inversely as the square root of a planet's distance, 
 will also be inversely as the square roots of the distances 
 approximately. We offer these views, however, only as sug- 
 gestions to others more competent to grapple with the question, 
 as promising a satisfactory solution of Bode's empirical formula. 
 
 If there be a wave of denser ether cylindrically disposed 
 around the vortex at the distance of Saturn, or between Saturn 
 and Uranus, we see why the law of densities and distances is 
 not continuous. For, if the law of density changes, it must be 
 owing to such a ring or wave. Inside this wave, the two forces 
 will be inverse ; but outside, one will be inverse, and the other 
 direct : hence, there should also be a change in the law of 
 distances. As this change does not take place until we pass 
 Uranus, it may be suspected that the great disparity in the 
 density of Saturn may be more apparent than real. The den- 
 sity of a planet is the relation between its mass and volume or 
 extension, no matter what the form of the body may be. From 
 certain observations of Sir Wm. Herschel the Titan of practical 
 astronomers the figure of Saturn was suspected to be that of 
 a square figure, with the corners rounded off, so as to leave 
 both the equatorial and polar zones flatter than pertained to a 
 true spheroidal figure. The existence of an unbroken ring 
 around Saturn, certainly attaches a peculiarity to this planet 
 which prepares us to meet other departures from the usual 
 
 * This is, perhaps, the nearest ratio of the densities and distances. 
 
MECHANICAL THEORY OF STOEMS. 169 
 
 order. And when we reflect on the small density, and rapid 
 rotation, the formation of this ring, and the figure suspected by 
 Sir Wm. Herschel, it is neither impossible nor improbable, that 
 there may be a cylindrical vacant space surrounding the axis 
 of Saturn, or at least, that his solid parts may be cylindrical, 
 and his globular form be due to elastic gases and vapors, which 
 effectually conceal his polar openings. And also, by dilating 
 and contracting at the poles, in consequence of inclination to 
 the radial stream, (just as the earth's atmosphere is bulged out 
 sufficiently to affect the barometer at certain hours every day,) 
 give that peculiarity of form in certain positions of the planet 
 in its orbit. Justice to Sir Wm. Herschell requires that his ob- 
 servations shall not be attributed to optical illusions. This 
 view, however, which may be true in the case of Saturn, would 
 be absurd when applied to the earth, as has been done within 
 the present century. From these considerations, it is at least 
 possible, that the density of Saturn may be very little less, or 
 even greater than the density of Uranus, and be in harmony 
 with the law of distances. 
 
 It is now apparently satisfactorily determined, that Neptune 
 is denser than Uranus, and the law being changed, we must 
 look for transneptunean planets at distances corresponding with 
 the new law of arrangement. But there are other modifying 
 causes which have an influence in fixing the precise position 
 of equilibrium of a planet. Each planet of the system possess- 
 ing rotation, is surrounded by an ethereal vortex, and each 
 vortex has its own radial stream, the force of which in opposing 
 the radial stream of the sun, depends on the diameter and den- 
 sity of the planet, on the velocity of rotation, on the inclination 
 of its axis, and on the density of the ether at each particular 
 vortex ; but the numerical verification of the position of each 
 planet with the forces we have mentioned, cannot be made in 
 the present state of the question. There is one fact worthy of 
 note, as bearing on the theory of vortices in connection with 
 
 -8 
 
170 MECHANICAL THEORY OF STORMS. 
 
 the rotation of the planets, viz. : that observation has deter- 
 mined that the axial rotation and sidereal revolution of the 
 secondaries, are identical ; thus showing that they are without 
 vortices, and are motionless relative to the ether of the vortex 
 to which they belong. We may also advert to the theory of 
 Doctor Olbers, that the asterodial group, are the fragments of 
 a larger planet which once filled the vacancy between Mars and 
 Jupiter. Although this idea is not generally received, it is 
 gathering strength every year by the discovery of other frag- 
 ments, whose number now amounts to twenty-six. If the idea 
 be just, our theory offers an explanation of the great differences 
 observable in the mean distances of these bodies, and which would 
 otherwise form a strong objection against the hypothesis. For 
 if these little planets be fragments, there will be differences of 
 density according as they belonged to the central or superficial 
 parts of the quondam planet, and their mean distances must 
 consequently vary also. 
 
 There are some other peculiarities connecting the distances 
 and densities, to which we shall devote a few words. In the 
 primordial state of the system, when the nebulous masses ag- 
 glomerated into spheres, the diameter of these nebulous spheres 
 would be determined by the relation existing between the rota- 
 tion of the mass, and the gravitating force at the centre ; for 
 as long as the centrifugal force at the equator exceeded the 
 gravitating force, there would be a continual throwing off of 
 matter from the equator, as fast as it was brought from the 
 poles, until a balance was produced. It is also extremely prob- 
 able, (especially if the elementary components of water are as 
 abundant in other planets as we have reason to suppose them 
 to be on the earth,) that the condensation of the gaseous planets 
 into liquids and solids, was effected in a brief period of time* 
 leaving the lighter and more elastic substances as a nebulous 
 
 * This is an important consideration, as bearing on the geology of 
 the earth. 
 
MECHANICAL THEORY OF STORMS. 171 
 
 atmosphere around globes of serai-fluid matter, whose diameters 
 have never been much increased by the subsequent conden- 
 sation of their gaseous envelopes. The extent of these atmos- 
 pheres being (in the way pointed out) determined by the rota- 
 tion, their subsequent condensation has not therefore changed 
 the original rotation of the central globe by any appreciable 
 quantity. The present rotation of the planets, is therefore com- 
 petent to determine the former diameters of the nebulous plan- 
 ets, i. e., the limit where the present central force would be 
 balanced by the centrifugal force of rotation. If we make the 
 calculation for the planets, and take for the unit of each planet 
 its present diameter, we shall find that they have condensed 
 from their original nebulous state, by a quantity dependent on 
 the distance from the centre of the system ; and therefore on 
 the original temperature of the nebulous mass at that particular 
 distance. Let us make the calculation for Jupiter and the 
 earth, and call the original nebulous planets the nucleus of the 
 vortex. We find the 
 
 Equatorial diameter of Jupiter's nucleus in equatorial diame- 
 ters of Jupiter =2.21, and the equatorial diameter of the earth's 
 nucleus, in equatorial diameters of the earth =6.59. Now, if 
 we take the original temperature of the nebulous planets to be 
 inversely, as the squares of the distances from the sun, and their 
 volumes directly as the cubes of the diameters in the unit of 
 each, we find that these cubes are to each other, in the inverse 
 ratio of the squares of the planet's distances ; for, 
 
 2.21 s : 6.59 3 : : I 3 : 5.2 8 , 
 
 showing that both planets have condensed equally, allowing 
 for the difference of temperature at the beginning. And we 
 shall find, beginning at the sun, that the diameters of the neb- 
 ulous planets, ceteris paribus, diminish outwards, giving for the 
 nebulous sun a diameter of 16,000,000 miles,* thus indicating 
 his original great temperature. 
 
 * It is not as likely that the condensation of the sun was so sudden 
 
172 MECHANICAL THEORY OF STORMS. 
 
 That the original nebulous planets did rotate in the same 
 time as they do at present, is proved by Saturn's ring ; for if 
 we make the calculation, we find that the nucleus of the 
 Saturnian vortex was just about twice the diameter of Saturn. 
 Now, the diameter of the planet is about 80,000 miles, which 
 will also be the semi-diameter of the nebulous planet ; and the 
 middle of the outer ring has also a semi-diameter of 80,000 
 miles ; therefore, the ring is the equatorial portion of the orig- 
 inal nebulous planet, and ought, on this theory, to rotate in the 
 same time as Saturn. According to Sir John Herschel, Saturn 
 rotates in 10 hours, 29 minutes, and 17 seconds, and the ring 
 rotates in 10 hours, 29 minutes, and 17 seconds : yet this is not 
 the periodic time of a satellite, at the distance of the middle of 
 the ring ; neither ought the rings to rotate in the same time ; yet 
 as far as observation can be trusted, both the inner and outer ring 
 do actually rotate in the same time. The truth is, the ring rotates 
 too fast, if we derive its centrifugal force from the analogy of 
 its satellites ; but it is, no doubt, in equilibrium ; and the effect- 
 ive mass of Saturn on the satellites is less than the true ma^ . 
 in consequence of his radial stream being immensely increased 
 by the additional force impressed on the ether, by the centri- 
 fugal velocity of the ring. If this be so, the mass of Saturn, 
 derived from one of the inner satellites, will be less than the 
 same mass derived from the great satellite, whose orbit is con- 
 siderably inclined. The analogy we have mentioned, between 
 the diameters of the nebulous planets and their distances, does 
 not hold good in the case of Saturn, for the reason already as- 
 signed, viz. : that the nebulous planet was probably not a globe, 
 but a cylindrical ring, vacant around the axis, as there is reason 
 to suppose is the case at present. 
 
 And now we have to ask the question, Did the ether involved 
 in the nebulous planets rotate in the same time ? This does not 
 
 as that of the planets, and therefore ill this case this distance is only 
 approximate. 
 
MECHANICAL THEOEY OF STORMS. 173 
 
 necessarily follow. The ether will undoubtedly tend to move 
 with increasing velocity to the very centre of motion, obeying 
 the great dynamical principle when unresisted. If resisted, the 
 law will perhaps be modified ; but in this case, its motion of 
 translation will be converted into atomic motion or heat, accord- 
 ing to the motion lost by the resistance of atomic matter. This 
 question has a bearing on many geological phenomena. As 
 regards the general effect, however, the present velocity of the 
 ether circulating round the planets, may be considered much 
 greater than the velocities of the planets themselves. 
 
 PERTURBATIONS DUE TO THE ETHER. 
 
 In these investigations it is necessary to bear in mind that 
 the whole resisting power of the ether, in disturbing the planet- 
 ary movements, is but small, in comparison with gravitation. 
 We will, however, show that, in the case of the planets, there 
 is a compensation continually made by this resistance, which 
 .eaves but a very small outstanding balance as a disturbing 
 power. If we suppose all the planets to move in the central 
 plane of the vortex in circular orbits, and the force of the radial 
 stream, (or that portion which is not in accordance with the law 
 of gravitation,) to be inversely as the square roots of the dis- 
 tances from the sun, it is evident, from what has been advanced, 
 that an equilibrium could still obtain, by variations in the densi- 
 ties, distances and diameters of the planets. Supposing, again, 
 that the planets still move in the same plane, but in elliptical 
 orbits, and that they are in equilibrium at their mean distances, 
 under the influence or action of the tangential current, the 
 radial stream, and the density of the ether ; we see that the 
 force of the radial stream is too great at the perihelion, and too 
 small at the aphelion. At the perihelion the planet is urged 
 from the sun and at the aphelion towards the sun. The density 
 and consequent momentum is also relatively too great at the 
 
174 MECHANICAL THEORY OF STORMS. 
 
 perihelion, which also urges the planet from the sun, and at the 
 aphelion, relatively too small, which urges the planet towards 
 the sun ; and the law is the same in both cases, being null at 
 the mean distance of the planet, and at a maximum at the 
 apsides ; it is, consequently, as the cosine of the planets eccen- 
 tric anomaly at other distances, and is positive or negative, 
 according as the planet's distance is above or below the" mean. 
 
 At the planet's mean distance, the circular velocity of the vor- 
 tex is equal to the circular velocity of the planet, and, at differ- 
 ent distances, is inversely in the sub-duplicate ratio of those 
 distances. But the circular velocity of a planet in the same 
 orbit, is in the simple ratio of the distances inversely. At the 
 perihelion, the planet therefore moves faster than the ether of 
 the vortex, and at the aphelion, slower ; and the difference is as 
 the square roots of the distances ; but the force of resistance is 
 as the square of the velocity, and is therefore in the simple ratio 
 of the distances, as we have already found for the effect of the 
 radial stream, and centrifugal momentum of the internal ether. 
 At the perihelion this excess of tangential velocity creates a 
 resistance, which urges the planet towards the sun, and at the 
 aphelion, the deficiency of tangential velocity urges the planet 
 from the sun, the maximum effect being at the apsides of the 
 orbit, and null at the mean distances. In other positions it is, 
 therefore, as the cosines of the eccentric anomaly, as in the 
 former -case ; but in this last case it is an addititious force at the 
 perihelion, and an ablatitious force at the aphelion, whereas the 
 first disturbing force was an ablatitious force at the perihelion, 
 and an addititious force at the aphelion ; therefore, as we must 
 suppose the planet to be in equilibrium at its mean distance, it 
 is in equilibrium at all distances. Hence, a planet moving in 
 the central plane of the vortex, experiences no disturbance from 
 the resistance of the ether. 
 
 As the eccentricities of the planetary orbits are continually 
 changing under the influence of the law of gravitation, we 
 
MECHANICAL THEOKY OF STOEMS. 175 
 
 must inquire whether, under these circumstances, such a change 
 would not produce a permanent derangement by a change in 
 the mean force of the radial stream, so as to increase or dimin- 
 ish the mean distance of the planet from the sun. The law of 
 force deduced from the theory for the radial stream is as the 
 2.5 power of the distances inversely. But, by dividing this 
 ratio, we may make the investigation easier ; for it is equivalent 
 to two forces, one being as the squares of the distances, and 
 another as the square roots of the distances. For the former 
 force, we find that in orbits having the same major axis the 
 mean effect will be as the minor axis of the ellipse inversely, 
 so that two planets moving in different orbits, but at the same 
 mean distance, experience a less or greater amount of centri- 
 pulsive force from this radial stream, according as their orbits 
 are of less or greater eccentricity, and this in the ratio of the 
 minor axis. On the other hand, under the influence of a force 
 acting centripulsively in the inverse ratio of the square roots of 
 the distances, we find the mean effect to be as the minor axis 
 of the ellipse directly, so that two planets in orbits of different 
 eccentricity, but having the same major axis, experience a 
 different amount from the action of this radial stream, the 
 least eccentric orbit being that which receives the greatest mean 
 effect. By combining these two results, we get a ratio of 
 equality; and, consequently, the action of the radial stream 
 will be the same for the same orbit, whatever change may take 
 place in the eccentricity, and the mean distance of the planet 
 will be unchanged. A little consideration will also show that 
 the effect of the centrifugal momentum due to the density of 
 ether will also be the same by change of eccentricity ; for the 
 positive will always balance the negative effect at the greatest 
 and least distances of the planet. The same remark applies to 
 the effect of the tangential current, so that no change can be 
 produced in the major axes of the planetary orbits by change 
 of eccentricity, as an effect of the resistance of the ether. 
 
176 MECHANICAL THEORY OF STOKMS. 
 
 We will now suppose a planet's orbit to be inclined to the 
 central plane of the vortex, and in this case, also, we find, that 
 the action of the radial stream tends to increase the inclination 
 in one quadrant as much as it diminishes it in the next quad- 
 rant, so that no change of inclination will result. But, if the 
 inclination of the orbit be changed by planetary perturbations, 
 the mean effect of the radial stream will also be changed, and 
 this will tell on the major axis of the orbit, enlarging the orbit 
 when the inclination diminishes, and contracting it when it 
 increases. The change of inclination, however, must be re- 
 ferred to the central plane of the vortex. Notwithstanding the 
 perfection of modern analysis, it is confessed that the recession 
 of the moon's nodes does yet differ from the theory by its 
 350th part, and a similar discrepancy is found for the advance 
 of the perigee.* This theory is yet far too imperfect to say 
 that the action of the ethereal medium will account for these 
 discrepancies ; but it certainly wears a promising aspect, worthy 
 the notice of astronomers. There are other minute discordan- 
 cies between theory and observation in many astronomical 
 phenomena, which theory is competent to remove. Some of 
 these we shall notice presently ; and, it may be remarked, that 
 it is in those minute quantities which, in astronomy, are usually 
 attributed to errors of observation, that this theory will event- 
 ually find the surest evidence of its truth. 
 
 KEPLER'S THIRD LAW ONLY APPROXIMATELY TRUE. 
 
 But it may be asked : If there be a modifying force in as- 
 tronomy derived from another source than that of gravitation, 
 why is it that the elements of the various members of the 
 system derived solely from gravitation should be so perfect ? 
 To this it may be answered, that although astronomers have 
 endeavored to derive every movement in the heavens from that 
 * Mechanique Celeste. Theory of the Moon. 
 
MECHANICAL THEORY OF STORMS. 177 
 
 great principle, they have but partially succeeded. Let us not 
 surrender our right of examining Nature to the authority of a 
 great name, nor call any man master, either in moral or physical 
 science. It is well known that Kepler's law of the planetary 
 distances and periods, is a direct consequence of the Newtonian 
 law of gravitation, and that the squares of the periodic times 
 ought to be proportional to the cubes of the mean distances. 
 These times are given accurately by the planets themselves, by 
 the interval elapsing between two consecutive passages of the 
 node, and as in the case of the ancient planets we have obser- 
 vations for more than two thousand years past, these times are 
 known to the fraction of the second. The determination of the 
 distances however, depends on the astronomer, and a tyro in 
 the science might suppose that these distances were actually 
 measured ; and so they are roughly ; but the astronomer does 
 not depend on his instruments, he trusts to analogy, and the 
 mathematical perfection of a law, which in the abstract is true ; 
 but which he does not know is rigidly exact when applied to 
 physical phenomena. From the immense distance of the planets 
 and the smallness of the earth, man is unable to command a 
 base line sufficiently long, to make the horizontal parallax a 
 sensible angle for the more distant planets ; and there are diffi- 
 culties of no small magnitude to contend with, with those that 
 are the nearest. In the occasional transit of Venus across the 
 sun, however, he is presented with a means of measuring on an 
 enlarged scale, from which the distance of the sun is deter- 
 mined ; and by analogy the distance of all the planets. Even 
 the parallax of the sun itself is only correct, by supposing that 
 the square of the periodic time of Venus is in the same propor- 
 tion to the square of the periodic time of the earth as the cube 
 of her distance is to the cube of the earth's distance. Our next 
 nearest planet is Mars, and observations on this planet at its op- 
 position to the sun, invariably give a larger parallax for the 
 sun Venus giving 8.5776" while Mars gives about 10". It 
 
 8* 
 
178 MECHANICAL THEOEY OF STOKMS. 
 
 is true that the first is obtained under more favorable circum- 
 stances ; but this does not prove the last to be incorrect. It is 
 well known that the British Nautical Almanac contains a list 
 of stars lying in the path of the planet Mars about opposition, 
 (for the very purpose of obtaining a correct parallax,) that mi- 
 nute differences of declination may be detected by simultaneous 
 observations in places having great differences of latitude. Yet 
 strange to say, the result is discredited when not conformable to 
 the parallax given by Venus. If then, we cannot trust the par- 
 allax of Mars, a fortiori, how can we trust the parallax of Ju- 
 piter, and say that his mean distance exactly corresponds to his 
 periodic time? Let us suppose, for instance, that the radius 
 vector of Jupiter fell short of that indicated by analogy by 
 10,000 miles, we say that it would be extremely difficult, nay, 
 utterly impossible, to detect it by instrumental means. Let not 
 astronomers, therefore, be too sure that there is not a modifying 
 cause, independent of gravitation, which they will yet have to 
 recognize. The moon's distance is about one-fourth of a mil- 
 lion of miles, and Neptune's 2854 millions, or in the ratio of 
 10,000 to 1 ; yet even the moon's parallax is not trusted in de- 
 termining her mass, how then shall we determine the parallax 
 of Neptune ? It is therefore possible that the effective action of 
 the sun is in some small degree different, on the different planets, 
 whether due to the action of the ether, to the similarity or dis- 
 similarity of material elements, to the temperature of the dif- 
 ferent bodies, or to all combined, is a question yet to be con- 
 sidered. 
 
 As another evidence of the necessity of modifying the strict 
 wording of the Newtonian law, it is found that the disturbing 
 action of Jupiter on different bodies, gives different values for 
 the mass of Jupiter. The mass deduced from Jupiter's action 
 on his satellites, is different from that derived from the pertur- 
 bations of Saturn, and this last does not correspond with that 
 
MECHANICAL THEORY OF STOEMS. 179 
 
 given by Juno : Vesta also gives a different mass from the 
 comet of Encke, and both vary from the preceding values.* 
 
 In the analytical investigation of planetary disturbances, the 
 disturbing force is usually divided into a radial and tangential 
 force ; the first changing the law of gravitation, to which law 
 the elliptic form of the orbit is due. The radial disturbing 
 force, therefore, being directed to or from the centre, can have 
 iiO influence over the first law of Kepler, which teaches that 
 the radius vector of each planet having the sun as the centre, 
 describes equal areas in equal times. If the radial disturbing 
 force be exterior to the disturbed body, it will diminish the 
 central force, and cause a progressive motion in the aphelion 
 point of the orbit. In the case of the moon this motion is very 
 rapid, the apogee making an entire revolution in 3232 days. 
 Does this, however, correspond with the law of gravitation \ 
 Sir Isaac Newton, in calculating the effect of the sun's disturb- 
 ing force on the motion of the moon's apogee, candidly concludes 
 thus : " Idoque apsis summa singulis revolutionibus progrediendo 
 conficit 1 31' 28". Apsis lunse est duplo velocior circiter." 
 As there was a necessity for reconciling this stubborn fact with 
 the theory, his followers have made up the deficiency by resort- 
 ing to the tangential force, or, as Clairant proposed, by con- 
 tinuing the approximations to terms of a higher order, or to 
 the square of the disturbing force. 
 
 Now, in a circular orbit, this tangential force will alternately 
 increase and diminish the velocity of the disturbed body, with- 
 out producing any permanent derangement, the same result 
 would obtain in an elliptical orbit, if the position of the major 
 axis were stationary. In the case of the moon, the apogee is 
 caused to advance by the disturbing power of the radial force, 
 and, consequently, an exact compensation is not effected : there 
 remains a small excess of velocity which geometers have con- 
 sidered equivalent to a doubling of the radial force, and have 
 *Mechanique Celeste. Masses of the planets. 
 
180 MECHANICAL THEOKY OF STOEMS. 
 
 thus obviated the difficulty. To those not imbued with the 
 profound penetration of the modern analyst, there must ever 
 appear a little inconsistency in this result. The major axis of a 
 planet's orbit depends solely on the velocity of the planet at a 
 given distance from the sun, and the tangential portion of the 
 disturbance due to the sun, and impressed upon the moon, 
 must necessarily increase and diminish alternately the velocity 
 of the moon, and interfere with the equable description of the 
 areas. If, then, there be left outstanding a small excess of 
 velocity over and above the elliptical velocity of the moon, at 
 the end of each synodical revolution, in consequence of the 
 motion impressed on the moon's apogee by the radial force, the 
 legitimate effect would be a small enlargement of the lunar 
 orbit every revolution in a rapidly-increasing ratio, until the 
 moon would at last be taken entirely away. In the great 
 inequality of Jupiter and Saturn, this tangential force is not 
 compensated at each revolution, in consequence of continual 
 changes in the configuration of the two planets at their helio- 
 centric conjunctions, with respect to the perihelion of their 
 orbits, and the near commensurability of their periods ; arid the 
 effect of the tangential force is, in this case, legitimately im- 
 pressed on the major axes of the orbits. But why (we may 
 ask) should not this also be expended on the motion of the 
 aphelion as well as in the case of the moon ? Astronomy can 
 make no distinctions between the orbit of a planet and the 
 orbit of a satellite. And, we might also ask, why the tangen- 
 tial resistance to the comet of Encke should not also produce a 
 retrograde motion in the apsides of the orbit, instead of 
 diminishing its period ? To the honor of Newton, be it remem- 
 bered, that he never resorted to an explanation of this phenom- 
 enon, which would vitiate that fundamental proposition of his 
 theory, in which the major axis of the orbit is shown to depend 
 on the velocity at any given distance from the focus. 
 
 Some cause, however, exists to double the motion of the 
 
MECHANICAL THEORY OF STOKMS. 181 
 
 apogee, and that there is an outstanding excess of orbital 
 velocity due to the tangential force, is also true. This excess 
 may tell in the way proposed, provided some other arrangement 
 exists to prevent a permanent dilation of the lunar orbit ; and 
 this provision may be found in the increasing density of the 
 ether, which prevents the moon overstepping the bounds pre- 
 scribed by her own density, and the force of the radial stream 
 of the terral vortex. In the case of Jupiter and Saturn, their 
 mutual action is much less interfered with by change of density 
 in the ether in the enlarged or contracted orbit, and, conse- 
 quently, the effect is natural. Thus, we have in the law of 
 density of the ethereal medium a better safeguard to the 
 stability of the dynamical balance of the system, than in the 
 profound and beautiful Theorems of La Grange. It will, of 
 course, occur to every one, that we are not to look for the same 
 law in every vortex, and it will, therefore, appear as if the 
 satellites of Jupiter, whose theory is so well known, should 
 render apparent any deviation between their periodic times and 
 the periodic times of the contiguous parts of the vortex, which 
 would obtain, if the density of the ether in the Jovian vortex 
 were not as the square roots of the distances directly. But, we 
 have shown how there can be a balance preserved, if the tan- 
 gential resistance of the vortex shall be equal and contrary at 
 the different distances at which the satellites are placed ; that 
 is, if these two forces shall follow the same law. These are 
 matters, however, for future investigation. 
 
 LIGHT AND HEAT. 
 
 But will not the admission of a vorticose motion of the 
 ethereal medium, affect the aberration of light ? It is well 
 known that the question has been mooted, whether the velocity 
 of reflected light is the same as that of direct light. The value 
 of aberration having been considered 20".25, from the eclipses 
 
182 MECHANICAL THEORY OF STORMS. 
 
 of Jupiter's satellites, while later determinations, from observa- 
 tions on Polaris, give 20".45. It cannot be doubted that light, 
 in traversing the central parts of the solar vortex, that is, having 
 to cross the whole orbit of the earth, should pass this distance 
 in a portion of time somewhat different to a similar distance 
 outside the earth's orbit, where the density is greater, and con- 
 sequently induce an error in the aberration, determined by the 
 eclipses of Jupiter's satellites. In the case of Polaris, the cir- 
 cumstances are more equal ; still, a difference ought to be de- 
 tected between the deduced aberration in summer and in 
 winter, as, in the first case, the light passes near the axis of the 
 solar vortex, where (according to the theory) a change of dens- 
 ity occurs. This is an important practical question, and the 
 suggestion is worthy attention. Now, the questions occurs, 
 will light pass through the rarefied space with greater velocity 
 than through the denser ether beyond ? From recent experi- 
 ments, first instituted by Arago, it is determined that light 
 passes with less velocity through water than through air ; and 
 one result of these experiments is the confirmation they give to 
 the theory of Fresnel, that the medium which conveys the 
 action of light partly partakes of the motion of the refracting 
 body. This of itself is a strong confirmation of this theory of 
 an ethereal medium. It may also be remarked, that every test 
 applied to the phenomenon of light, adds additional strength to 
 the undulatory theory, at the expense of the Newtonian theory 
 of emission. As light occupies time in traversing space, it must 
 follow from the theory that it does not come from the radiant 
 point exactly in straight lines, inasmuch as the ether itself is in 
 motion tangentially, the velocity being in the sub-duplicate 
 ratio of the distances from the sun inversely 
 
 May not that singular phenomenon, the projection of a star 
 on the moon's disc, at the time of an occultation, be due to 
 this curvature of the path of a ray of light, by considering that 
 the rays from the moon have less intensity, but more mechanical 
 
MECHANICAL THEORY OF STORMS. 183 
 
 momentum, and consequently more power to keep a straight 
 direction ? Let us explain : we have urged that light, as well 
 as heat, is a mechanical effect of atomic motion, propagated 
 through an elastic medium ; that, ceteris paribus, the product 
 of matter by its motion is ever a constant quantity for equal 
 spaces throughout the universe, in a word, that it is, and must 
 necessarily be, a fundamental law of nature. All departures 
 from this law are consequences of accidental arrangements, 
 which can only be considered of temporary duration. Our 
 knowledge of planetary matter requires the admission of differ- 
 ences in the density, form, and size of ultimate atoms, and, ac- 
 cording to the above law, when the atoms are of uniform tem- 
 perature or motion, the product of the matter of each by its 
 motion, when reduced to the same space, will be constant. The 
 momentum of two different atoms, therefore, we will consider 
 equal, for the sake of illustration ; yet this momentum is made 
 up of two different elements, matter and motion. Let us ex- 
 aggerate the difference, and assign a ratio of 1000 to 1. Sup- 
 pose a ball of iron of 1000 Ibs., resting upon a horizontal 
 plane, should be struck by another ball of 1 lb., having a 
 motion of 1000 feet in a second, and, in a second case, should 
 be struck by a ball of 1000 Ibs., having a velocity of 1 foot per 
 second, the momentum of each ball is similar ; but experience 
 proves that the motion impressed on the ball at rest is not 
 similar ; the ponderous weight and slow motion is far more 
 effective in displacing this ball, for the reason that time is essen- 
 tial to the distribution of the motion. If the body to be struck 
 be small as, for instance, a nail, a greater motion and less mat- 
 ter is more effective than much matter and little motion. Hence, 
 we have a distinction applicable to the difference of momentum 
 of luminous and calorific rays. The velocity of a wave of sound 
 through the atmosphere, is the same for the deep-toned thun- 
 der and the shrillest whistle, being dependent on the density 
 
184 MECHANICAL THEOEY OF STOEMS. 
 
 of the medium, and not on the source from which it emanates. 
 So it is in the ethereal medium. 
 
 This view is in accordance with the experiments of M. Dela- 
 roche and Melloni, on the transmission of light and heat through 
 diaphanous bodies the more calorific rays feeling more and 
 more the influence of thickness, showing that more motion was 
 imparted to the particles of the diaphanous substance by the 
 rays possessing more material momentum, and still more when 
 the temperature of the radiating body was low, evidently ana- 
 logous to the illustration we have cited. Light may therefore 
 be regarded as the effect of the vibration of atoms having little 
 mass, and as this mass increases, the rays become more calorific, 
 and finally the calorific effect is the only evidence of their exist- 
 ence ; as towards the extreme red end of the spectrum they 
 cease to be visible, owing to their inability to impart their vi- 
 brations to the optic nerve. This may also influence the law 
 of gravitation. In this we have also an explanation of the dis- 
 persion of light. The rays proceeding from atoms of small mass 
 having less material momentum, are the most refrangible, and 
 those possessing greater material momentum, are the least re- 
 frangible ; so that instead of presenting a difficulty in the undu- 
 latory theory of light, this dispersion is a necessary consequence 
 of its first principles. 
 
 It is inferred from the experiments cited, and the facts ascer- 
 tained by them, viz. : that the velocity of light in water is less 
 than its velocity in air; that the density of the ether is greater 
 in the first case ; but this by no means follows. We have ad- 
 vocated the idea, that the ethereal medium is less dense within 
 a refracting body than without. We regard it as a funda- 
 mental principle. Taking the free ether of heaven ; the vibra- 
 tions in the denser ether will no doubt be slowest ; but within 
 a refracting body we must consider there is motion lost, or liaht 
 absorbed, and the time of the transmission is thus increased. 
 
 There has been a phenomenon observed in transits of Mer- 
 
MECHANICAL THEORY OF STORMS. 185 
 
 cury and Venus across the sun, of which no explanation has 
 been rendered by astronomers. When these planets are visible 
 on the solar disc, they are seen surrounded by rings, as if the 
 light was intercepted and increased alternately. This is no 
 doubt due to a small effect of interference, caused by change 
 of velocity in passing through the rarefied nucleus of these 
 planetary vortices, near the body of the planet, and through 
 the denser ether beyond, acting first as a concave, and secondly 
 as a convex refracting body ; always considering that the ray 
 will deviate towards the side of least resistence, and thus inter- 
 fere. 
 
 That heat is simply atomic motion, and altogether mechan- 
 ical, is a doctrine which ought never to have been questioned. 
 The interest excited by the bold experiments of Ericson, has 
 caused the scientific to suspect, that heat can be converted into 
 motion, and motion into heat a fact which the author has 
 considered too palpable to deny for the last twenty years. He 
 has ever regarded matter and motion as the two great princi- 
 ples of nature, ever inseparable, yet variously combined ; and 
 that without these two elements, we could have no conception 
 of anything existing. 
 
 It may be thought by some, who are afraid to follow truth 
 up the rugged precipices of the hill of knowledge, that this 
 theory of an interplanetary plenum leads to materialism ; for- 
 getting, that He who made the world, formed it of matter, and 
 pronounced it " very good." We may consider ethereal matter, 
 in one sense, purer than planetary matter, because unaffected 
 by chemical laws. Whether still purer matter exists, it is not 
 for us to aver or deny. The Scriptures teach us that " there is 
 a natural body and there is a spiritual body." Beyond this we 
 know nothing. We, however, believe that the invisible world 
 of matter, can only be comprehended by the indications of that 
 which is visible ; yet while humbly endeavoring to connect by 
 
186 MECHANICAL THEOKY OF STOEMS. 
 
 one common tie, the various phenomena of matter and motion, 
 we protest against those doctrines which teach the eternal dura- 
 tion of the present order of things, as being incompatible with 
 the analogies of the past, as well as with the revelations of the 
 future. 
 
SECTION FIFTH. 
 
 COMETARY PHENOMENA. 
 
 THE planetary arrangements of the solar system are all d 
 priori indications of the theory of vortices, not only by the 
 uniform direction of the motions, the circular orbits in which 
 these motions are performed, the near coincidence of the planes 
 of these orbits, and the uniform direction of the rotation of the 
 planets themselves ; but, also, by the law of densities and dis- 
 tances, which we have already attempted to explain. In the 
 motions of comets we find no such agreement. These bodies 
 move in planes at all possible inclinations in orbits extremely 
 eccentrical and without any general direction as many moving 
 contrary to the direction of the planets as in the opposite 
 direction ; and when we consider their great volume, and their 
 want of mass, it appears, at first sight, that comets do present 
 a serious objection to the theory. We shall point out, however, 
 a number of facts which tend to invalidate this objection, and 
 which will ultimately give the preponderance to the opposite 
 argument. 
 
 Every fact indicative of the nature of comets proves that the 
 nuclei are masses of material gases, similar, perhaps (at least in 
 the case of the short-period comets), to the elementary gases 
 of our own planet, and, consequently, these masses must be but 
 small. In the nascent state of the system, the radial stream of 
 the vortex would operate as a fan, purging the planetary mate- 
 rials of the least ponderable atoms, and, as it were, separating 
 
188 MECHANICAL THEOET OF STOKMS. 
 
 the wheat from the chaff. It is thus we conceive that the 
 average atomic density of each planet has been first determined 
 by the radial stream, and, subsequently, that the solidification 
 of the nebulous planets has, by their atomic density, assigned 
 to each its position in the system, from the consequent relation 
 which it established between the density of the ether within 
 the planet, and the density of the ether external to it, so that, 
 according to this view, a single isolated atom of the same 
 density as the mean atomic density of the earth could (ceteris 
 paribus) revolve in an orbit at the distance of the earth, and in 
 the same periodic time. This, however, is only advanced by 
 way of illustration. 
 
 The expulsive force of the radial stream would thus drive off 
 this cornetary dust to distances in some inverse ratio of the 
 density of the atoms ; but, a limit would ultimately be reached, 
 when gravitation would be relatively the strongest the last 
 force diminishing only as the squares of the distances, and the 
 first diminishing in the compound ratio of the squares and the 
 square roots of the distances. At the extreme verge of the 
 system, this cometary matter would accumulate, and, by accu- 
 mulation, would still further gather up the scattered atoms 
 the sweepings of the inner space and, in this condensed form, 
 would again visit the sun in an extremely elongated ellipse. It 
 does not, however, follow, that all comets are composed of such 
 unsubstantial materials. There may be comets moving in 
 parabolas, or even in hyperbolas bodies which may have been 
 accumulating for ages in the unknown regions of space, far 
 removed from the sun and stars, drifting on the mighty cur- 
 rents of the great ethereal ocean, and thus brought within the 
 sphere of the sun's attraction ; and these bodies may have no 
 analogy to the periodical comets of our system, which last are 
 those with which we are more immediately concerned. 
 
 The periodical comets known are clearly arranged into two 
 distinct classes one having a mean distance between Saturn 
 
MECHANICAL THEORY OF STORMS. 
 
 189 
 
 and Uranus, with a period of about seventy-five years, and 
 another class, whose mean distance assigns their position 
 between the smaller planets and Jupiter, having periods of 
 about six years. These last may be considered the siftings of 
 the smaller planets, and the first the refuse of the Saturnian 
 system. In this light we may look for comets having a mean dis- 
 tance corresponding to the intervals of the planets, rather than 
 to the distances of the planets themselves. One remarkable 
 fact, however, to be observed in these bodies is, that all their 
 motions are in the same direction as the planets, and, with one 
 exception, there is no periodical comet positively known whose 
 motion is retrograde. 
 
 The exception we have mentioned is the celebrated comet of 
 Halley, whose period is also about seventy-five years. In 
 reasoning on the resistance of the ether, we must consider that 
 the case can have very little analogy with the theory of pro- 
 jectiles in air; nor can we estimate the inertia of an infinitely 
 divisible fluid, from its resisting influence on atomic matter, by 
 a comparison of the resistance of an atomic fluid on an atomic 
 solid. Analogy will only justify comparisons of like with like. 
 The tangent of a comet's orbit, also, can only be tangential to 
 the circular motion of the ether at and near perihelion, which 
 is a very small portion of its period of revolution. As far as 
 the tangential resistance is concerned, therefore, it matters little 
 whether its motion be direct or retrograde. If a retrograde 
 comet, of short period and small eccentricity, were discovered 
 moving also near the central plane of the vortex, it would pre- 
 sent a very serious objection, as being indicative of contrary 
 motions in the nascent state of the system. There is no such 
 case known. So, also, with the inclinations of the orbits ; if 
 these be great, it matters little whether the comet moves in one 
 way or the other, as far as the tangential current of the vortex 
 is concerned. Yet, when we consider the average inclination 
 of the orbit, and not of its plane, we find that the major axes 
 
190 
 
 MECHANICAL THEOEY OF STOEMS. 
 
 of nearly all known cometary orbits are very little inclined to 
 the plane of the ecliptic. 
 
 In the following table of all the periodical comets known, the 
 inclination of the major axis of the orbit is calculated to the 
 nearest degree ; but all cometary orbits with very few excep- 
 tions, will be found to respect the ecliptic, and never to deviate 
 far from that plane : 
 
 Designations 
 of the Comets. 
 
 Periodic 
 times. 
 
 Inclination 
 of 
 Major Axes. 
 
 Motion 
 in Orbit. 
 
 Planetary 
 Intervals. 
 
 Encke 
 
 1818 
 
 3 years. 
 
 1 
 
 Direct 
 
 Mars & Ceres. 
 
 De Vico 
 
 1844 
 
 
 2 
 
 Direct 
 
 
 Faye 
 
 1843 
 
 
 4 
 
 Direct 
 
 Ceres 
 
 De Avrest 
 
 1851 
 
 From 
 
 1 
 
 Direct 
 
 
 Brorsen 
 
 1846 
 
 five 
 
 7 
 
 Direct 
 
 and 
 
 Messier 
 
 1766 
 
 to 
 
 
 
 Direct 
 
 
 Clausen 
 
 1743 
 
 six 
 
 
 
 Direct 
 
 Jupiter. 
 
 Pigott 
 
 1783 
 
 or 
 
 4 
 
 Direct 
 
 
 Pous 
 
 1819 
 
 seven 
 
 3 
 
 Direct 
 
 
 Biela 
 
 1826 
 
 years. 
 
 9 
 
 Direct 
 
 
 Blaupain 
 
 1819 
 
 
 2 
 
 Direct 
 
 
 Lexell 
 
 1770 
 
 
 1 
 
 Direct 
 
 
 Pous 
 
 1812 
 
 
 17 
 
 Direct 
 
 
 Olbers 
 
 1815 
 
 about 
 
 40 
 
 Direct 
 
 Saturn 
 
 De Vico 
 
 1846 
 
 75 
 
 13 
 
 Direct 
 
 and 
 
 Brorsen 
 
 1847 
 
 years. 
 
 12 
 
 Direct 
 
 Uranus. 
 
 Westphal 
 
 185.2 
 
 
 21 
 
 Direct 
 
 
 Halley 
 
 1682 
 
 
 16 
 
 Retrograde 
 
 
 From which it appears, that the objection arising from the 
 great inclination of the planes of these orbits is much less im- 
 portant than at first it appears to be. 
 
 Regarding then, that a comet's mean distance depends on its 
 mean atomic density, as in the case of the planets, the undue 
 enlargement of their orbits by planetary perturbations is inad- 
 missible. In 1770 Messier discovered a comet which ap- 
 proached nearer the earth than any comet known, and it was 
 found to move in a small ellipse with a period of five and a half 
 years ; but although repeatedly sought for, it was the opinion 
 
MECHANICAL THEORY OF STORMS. 191 
 
 oi; many, that it has neve r been since seen. The cause of this 
 Deeming anomaly is found by astronomers in the disturbing 
 power of Jupiter near which planet the comet must have 
 passed in 1779, but the comet was not seen in 1776 before it 
 passed near Jupiter, although a very close search was kept up 
 about this time. Now there are two suppositions in reference 
 to this body : the comet either moved in a larger orbit previous 
 to 1767, and was then caused by Jupiter to diminish its ve- 
 locity sufficiently to give it a period of five and a half years, and 
 that after perihelion it recovered a portion of its velocity in en- 
 deavoring to get back into its natural orbit ; or if moving in the 
 natural orbit in 1770, and by passing near Jupiter in 1779 this 
 orbit was deranged, the comet will ultimately return to that 
 mean distance although not necesarily having elements even ap- 
 proximating those of 1770. In 1844, September 15th, the au- 
 thor discovered a comet in the constellation Cetus, (the same 
 previously discovered by De Vico at Rome,) and from positions 
 estimated with the naked eye, approximately determined the 
 form of its orbit and its periodic time to be very similar to the 
 lost comet of 1770. These conclusions were published in a 
 western paper in October 1844, on which occasion he expressed 
 the conviction, that this was no other than the comet of 1770. 
 As the question bore strongly on his theory he paid the greater 
 attention to it, and had, previously to this time, often searched 
 in hopes of finding that very comet. Since then, M. Le Verrier 
 has examined the question of identity and given his decision 
 against it ; but the author is still sanguine that the comet of 
 1844 is the same as that of 1770, once more settled at its 
 natural distance from the sun. This comet returns to its peri- 
 helion on the 6th of August, 1855, according to Dr. Briinnow, 
 when, it is hoped, the question of identity will be reconsidered 
 with reference to the author's principles ; and, that when astrono- 
 mers become satisfied of this, they will do him the justice of 
 
192 MECHANICAL THEOEY OF STORMS. 
 
 acknowledging that he was the first who gave publicity to the 
 fact, that the " Lost Comet " was found. 
 
 That comets do experience a resistance, is undeniable ; but 
 not in the way astronomers suppose, if these views be correct. 
 The investigations of Professor Encke, of Berlin, on the comet 
 which bears his name, has determined the necessity of a correc- 
 tion, which has been applied for several returns with apparent 
 success. But there is this peculiarity about it, which adds 
 strength to our theory : " The Constant of Resistance " requires 
 a change after perihelion. The necessity for this change shows 
 the action of the radial stream. From the law of this force, 
 (reckoning on the central plane of the vortex,) there is an out- 
 standing portion, acting as a disturbing power, in the sub- 
 duplicate ratio of the distances inversely. If we only consider 
 the mean or average effect in orbits nearly circular, this force 
 may be considered as an ablatitious force at all distances below 
 the mean, counterbalanced by an opposite effect at all distances 
 above the mean. But when the orbits become very eccentrical, 
 we must consider this force as momentarily affecting a comet's 
 velocity, diminishing it as it approaches the perihelion, and 
 increasing it when leaving the perihelion. A resolution of this 
 force is also requisite for the comet's distance above the central 
 plane of the vortex, and a correction, likewise, for the intensity 
 of the force estimated in that plane. There is also a correction 
 necessary for the perihelion distance, and another for the tan- 
 gential current ; but we are only considering here the general 
 effect. By diminishing the comet's proper velocity in its orbit, 
 if we consider the attraction of the sun to remain the same, the 
 general effect may be (for this depends on the tangential portion 
 of the resolved force preponderating) that the absolute velocity 
 will be increased, and the periodic time shortened ; but after 
 passing the perihelion, with the velocity of a smaller orbit, there 
 is also superadded to this already undue velocity, the expulsive 
 power of the radial stream, adding additional velocity to the 
 
MECHANICAL THEORY OF STOEMS. 193 
 
 comet ; the orbit is therefore enlarged, and the periodic time 
 increased. Hence the necessity of changing the " Constant of 
 Resistance " after perihelion, and this will generally be found 
 necessary in all cometary orbits, if this theory be true. But 
 this question is one which may be emphatically called the most 
 difficult of dynamical problems, and it may be long before it is 
 fully understood. 
 
 According to the calculations of Professor Encke, the comet's 
 period is accelerated about 2 hours, 30 minutes, at each return, 
 which he considers due to a resisting medium. May it not rather 
 be owing to the change of inclination of the major axis of the orbit, 
 to the central plane of the vortex ? Suppose the inclination of 
 the plane of the orbit to remain unchanged, and the eccentricity 
 of the orbit also, if the longitude of the perihelion coincides with 
 that of either node, the major axis of the orbit lies in the eclip- 
 tic, and the comet then experiences the greatest mean effect 
 from the radial stream ; its mean distance is then, ceteris paribus, 
 the greatest. When the angle between the perihelion and the 
 nearest node increases, the mean force of the radial stream is 
 diminished, and the mean distance is diminished also. When 
 the angle is 90, the effect is least, and the mean distance least. 
 This is supposing the ecliptic the central plane of the vortex. 
 When Encke's formula was applied to Biela'a comet, it was in- 
 adequate to account for a tenth part of the acceleration ; and 
 although Biela moves in a much denser medium, and is of less 
 dense materials, even this taken into account will not satisfy the 
 observations, making no other change in Encke's formula. 
 We must therefore attribute it to changes in the elements of the 
 orbits of these comets. Now, the effect of resistance should also 
 have been noticed, as an acceleration of Halley's comet in 1835, 
 yet the period was prolonged. To show that our theory of the 
 cause of these anomalies corresponds with facts, we subjoin 
 the elements in the following tables, taken from Mr. Hind's 
 catalogue : 
 
 9 
 
194 MECHANICAL THEOEY OF STOEMS. 
 
 Date of 
 Perihelion. 
 
 1822 
 
 Longitude of 
 Perihelion. 
 
 157 11' 44" 
 
 Longitude of 
 nearest Node, 
 
 154 25' 9" 
 
 Difference of 
 Longitude. 
 
 2 46' 35" 
 
 1825 
 
 157 
 
 14 
 
 31 
 
 154 
 
 27 
 
 30 
 
 2 
 
 47 
 
 1 
 
 1829 
 
 157 
 
 17 
 
 53 
 
 154 
 
 29 
 
 32 
 
 2 
 
 48 
 
 21 
 
 1832* 
 
 157 
 
 21 
 
 1 
 
 154 
 
 32 
 
 9 
 
 2 
 
 41 
 
 52 
 
 1835 
 
 157 
 
 23 
 
 29 
 
 154 
 
 34 
 
 59 
 
 2 
 
 48 
 
 30 
 
 1838 
 
 157 
 
 27 
 
 4 
 
 154 
 
 36 
 
 41 
 
 2 
 
 50 
 
 23 
 
 1842 
 
 157 
 
 29 
 
 27 
 
 154 
 
 39 
 
 10 
 
 2 
 
 50 
 
 17 
 
 1845 
 
 157 
 
 44 
 
 21 
 
 154 
 
 19 
 
 33 
 
 3 
 
 24 
 
 48 
 
 1848 
 
 157 
 
 47 
 
 8 
 
 154 
 
 22 
 
 12 
 
 3 
 
 24 
 
 56 
 
 1852 
 
 157 
 
 51 
 
 2 
 
 154 
 
 23 
 
 21 
 
 3 
 
 27 
 
 41 
 
 111 this we see a regular increase of the angle, which ought to 
 be attended with a small acceleration of the comet ; but the 
 change of inclination of the orbit ought also to be taken into 
 consideration, to get the mean distance of the comet above the 
 plane of the vortex, and, by this, the mean force of the radial 
 stream. 
 
 In the following table, the same comparison is made for 
 Biela's comet: 
 
 Date of Peri- 
 helion. 
 
 Longitude of the 
 Perihelion. 
 
 Longitude of the 
 nearest Node. 
 
 Difference of Lon- 
 gitude. 
 
 1772 
 
 110 14' 54" 
 
 74 0' 1" 
 
 36 14' 53" 
 
 1806 
 
 109 32 23 
 
 71 15 15 
 
 38 17 8 
 
 1826 
 
 109 45 50 
 
 71 28 12 
 
 38 17 38f 
 
 1832 
 
 110 55 55 
 
 68 15 36 
 
 41 45 19 
 
 1846 
 
 109 2 20 
 
 65 54 39 
 
 43 7 41 
 
 Between 1832 and 1846, the increase of the angle is twice as 
 great for Biela as for Encke, and the angle itself throws the 
 major axis of Biela 10 above the ecliptic, whereas the angle 
 made by Encke's major axis, is only about 1 ; the cosine of the 
 
 * The orbit this year was determined under very unfavorable circum- 
 stances. 
 
 f According to other tables, this angle would be much greater than 
 is given in Mr. Hind's catalogue. 
 
MECHANICAL THEORY OF STORMS. 195 
 
 first angle, diminishes much faster therefore, and consequently 
 the same difference of longitude between the perihelion and 
 node, will cause a greater acceleration of Biela ; and according 
 to Prof. Encke's theory, Biela would require a resisting medium 
 twenty-five times greater than the cornet of Encke to reconcile 
 observation with the theory. Halley's comet can scarcely be 
 considered to have had an orbit with perfect elements before 
 1835. If they were known accurately for 1*759, we should no 
 doubt find, that the angle between the node and perihelion di- 
 minished in the interval between 1Y59 and 1835, as according 
 to the calculations of M. Rosenberg, the comet was six days 
 behind its time a fact fatal to the common ideas of a resisting 
 medium ; but this amount of error must be received as only 
 approximate. 
 
 No comet that has revisited the sun, has given astronomers 
 more trouble than the great comet of 1843. Various orbits 
 have been tried, elliptical, parabolic and hyperbolic ; yet none 
 will accord with all the observations. The day before this 
 comet was seen in Europe and the United States, it was seen 
 close to the body of the sun at Conception, in South America ; 
 yet this observation, combined with those following, would give 
 an orbital velocity due to a very moderate mean distance. 
 Subsequent observations best accorded with a hyperbolic orbit ; 
 and it was in view of this anomaly, that the late Sears C. 
 Walker considered that the comet came into collision with the 
 sun in an elliptical orbit, and its debris passed off again in a 
 hyperbola. That a concussion would not add to its velocity is 
 certain, and the departure in a hyperbolic orbit would be con- 
 trary to the law of gravitation. This principle is thus stated 
 by Newton : " In parabola velocitas ubique equalis est veloc- 
 itati corporis revolventis in circulo ad dimidiam distantiam ; in 
 ellipsi minor est in hyperbola major." (Vid.Prin. Lib. 1. Prop. 
 6 Cor. 7.) 
 
 But as regards the fact, it is probable that Mr. Walker's 
 
196 MECHANICAL THEORY OF STORMS. 
 
 views are correct, so far as the change from an ellipse to an 
 hyperbola is considered. The Conception observation cannot 
 be summarily set aside, and Professor Peirce acknowledges, that 
 " If it was made with anything of the accuracy which might be 
 expected from Captain Ray, it exhibits a decided anomaly in 
 the nature of the forces to which the comet was subjected dur- 
 ing its perihelion passage." The comet came up to the sun 
 almost in a straight line against the full force of the radial 
 stream ; its velocity must therefore necessarily have been di- 
 minished. After its perihelion, its path was directly from the 
 sun, and an undue velocity would be kept up by the auxiliary 
 force impressed upon it by the same radial stream ; and hence, 
 the later observations give orbits much larger than the early 
 ones, and there can be no chance of identifying this comet with 
 any of its former appearances, even should its orbit be elliptical. 
 This unexpected confirmation of the theory by the observation 
 of Capt. Ray, cannot easily be surmounted. 
 
 We must now endeavor to explain the physical peculiarities 
 of comets, in accordance with the principles laid down. The 
 most prominent phenomenon of this class is the change of diam- 
 eter of the visible nebulosity. It is a most singular circum- 
 stance, but well established as a fact, that a comet contracts in 
 its dimensions on approaching the sun, and expands on leaving 
 it. In 1829, accurate measures were taken on different days, 
 of the diameter of Encke's comet, and again in 1838. The 
 comet of 1618 was also observed by Kepler with this very ob- 
 ject, and also the comet of 1807; but without multiplying 
 instances, it may be asserted that it is one of those facts in 
 cometary phenomena, to which there are no exceptions. Ac- 
 cording to all analogy, the very reverse of this ought to obtain. 
 If a comet is chiefly vaporous, (as this change of volume would 
 seem to indicate,) its approach to the sun ought to be attended 
 by a corresponding expansion by increase of temperature. 
 When the contrary is observed, and invariably so, it ought to 
 
MECHANICAL THEOEY OF STORMS. 197 
 
 be regarded as an index of the existence of other forces besides 
 gravitation, increasing rapidly in the neighborhood of the sun ; 
 for the disturbing power of the sun's attraction would be to 
 enlarge the diameter of a comet in proportion to its proximity. 
 Now, the force of the radial stream, as we have shown, is as 
 the 2.5th power of the distances inversely. If this alternate 
 contraction and expansion be due to the action of this force, 
 there ought to be an approximate correspondence of the law of 
 the effect with the law of the cause. Arago, in speaking of 
 the cornet of 1829, states, "that between the 28th of October 
 and the 24th of December, the volume of the comet was 
 reduced as 16000 to 1, the change of distance in the meantime 
 only varying about 3 to 1." To account for this, a memoir was 
 published on the subject by M. Valz, in which he supposes an 
 atmosphere around the sun, whose condensation increases 
 rapidly from superincumbent pressure; so that the deeper 
 the comet penetrates into this atmosphere the greater will be 
 the pressure, and the less the volume. In this.it is evident, 
 that the ponderous nature of a resisting medium is not yet 
 banished from the schools. In commenting on this memoir, 
 Arago justly observes, that " there would be no difficulty in. this 
 if it could be admitted that the exterior envelope of the nebu- 
 losity were not permeable to the ether ; but this difficulty seems 
 insurmountable, and merits our sincere regret; for M. Valz's 
 ingenious hypothesis has laid down the law of variation of the 
 bulk of the nebulosity, as well for the short-period comet as for 
 that of 1618, with a truly wonderful exactness." Now, if we 
 make the calculation, we shall find that the diameter of the 
 nebulosity of a comet is inversely as the force of the radial 
 stream. This force is inversely as the 2.5 power of the dis- 
 tances from the axis, and not from the sun : it will, therefore, 
 be in the inverse ratio of the cosine of the comet's heliocentric 
 latitude to radius, and to this ratio the comet's distance ought 
 to be reduced. But, this will only be correct for the same 
 
198 MECHANICAL THEORY OF STOEMS. 
 
 plane or for equal distances above the ecliptic plane, considering 
 this last as approximately the central plane of the vortex. 
 From the principles already advanced, the radial stream is far 
 more powerful on the central plane than in more remote planes ; 
 therefore, if a comet, by increase of latitude, approaches near 
 the axis, thus receiving a larger amount of force from the radial 
 stream in that plane than pertains to its actual distance from 
 the sun, it will also receive a less amount of force in that plane 
 than it would in the central plane at the same distance from the 
 axis. Now, we do not know the difference of force at different 
 elevations above the central plane of the vortex ; but as the 
 two differences due to elevation are contrary in the'" effects 
 and tend to neutralize each other, we shall make the calculation 
 as if the distances were truly reckoned from the centre of the sun. 
 The following table is extracted from Arago's tract on 
 Comets, and represents the variations of the diameter of Encke's 
 comet at different distances from, the sun, the radius of the 
 orbis magnus being taken as unity. 
 
 Times of observation, Distances of the Real diameters 
 
 1828. comet from the sun. in radii of the earth. 
 
 Oct. 28 1.4617 79.4 
 
 Nov. 7 1.3217 ..... 64.8 
 
 Nov. 30 0.9668 29.8 
 
 Dec. 7 0.8473 19.9 
 
 Dec. 14 0.7285 11.3 
 
 Dec. 24 0.5419 3.1 
 
 In order the better to compare the diameters with the force, 
 we will reduce them by making the first numbers equal. 
 
 Distances. 
 
 TV ,>t Q ,.c, Tne 2 - 5th power Reduced 
 Diameters. of the Distances. Diameters. 
 
 1.4617 
 
 . . . 79.4 
 
 . . . 2.58 
 
 . . . 2.58 
 
 1.3217 
 
 . . . 64.8 
 
 . . . 2.01 
 
 ... 2.10 
 
 0.9668 
 
 . . . 29.8 
 
 . . . 0.92 
 
 . . . 0.97 
 
 0.8473 
 
 . . . 19.9 
 
 . . . 0.66 
 
 , . . 0.65 
 
 0.7285 
 
 . . . 11.3 
 
 . . . 0.45 
 
 . . . 0.37 
 
 0.5419 
 
 ... 3.1 
 
 . 0.21 
 
 . 0.10 
 
MECHANICAL THEORY OF STORMS. 199 
 
 This is a very close approximation, when we consider the 
 difficulty of micrometric measurement, and the fact, that as the 
 comet gets nearer to the sun, as at the last date of the table, 
 the diameter is more than proportion ably diminished by the 
 fainter nebulosity becoming invisible. But, there may be a 
 reality in the discrepancy apparent at the last date, as the 
 comet was then very near the plane of the ecliptic, and was, 
 consequently, exposed to the more violent action of the radial 
 stream. 
 
 To attempt to explain the modus agendi is, perhaps, pre- 
 mature. Our principal aim is to pioneer the way into the 
 labyrinth, and it is sufficient to connect this seeming anomaly 
 with the same general law we have deduced from other phe- 
 nomena. Still, an explanation may be given in strict accord- 
 ance with the general principles of the theory. 
 
 Admitting the nucleus of a comet to be gaseous, there is no 
 difficulty about the solution. According to Sir John Herschel, 
 "stars of the smallest magnitude remain distinctly vissible, 
 though covered by what appears the densest portion of their 
 substances; and since it is an observed fact, that the large 
 comets which have presented the appearance of a nucleus, have 
 yet exhibited no phases, though we cannot doubt that they 
 shine by the reflected solar light, it follows that even these can 
 only be regarded as great mi&ses of thin vapor." That comets 
 shine solely by reflected solar light, is a position that we shall 
 presently question ; but that they are masses of vapor is too evi- 
 dent to dispute. According to the same authority quoted above, 
 " If the earth were reduced to the one thousandth part of its actual 
 mass, its coercive power over the atmosphere would be dimin- 
 ished in the same proportion, and in consequence the latter 
 would expand to a thousand times its actual bulk" If this 
 were so, and comets composed of the elementary gases, some of 
 them would have very respectable masses, as the nuclei are fre- 
 quently not more than 5,000 miles in diameter, and consequently 
 
200 MECHANICAL THEOBY OF STORMS. 
 
 it becomes important to examine the principle. From all ex- 
 periments the density of an elastic fluid is directly as the com- 
 pressing force ; and if a cylinder reached to the top of our 
 atmosphere, compressed by the gravitation of the earth, consid- 
 ered equal at each end of the cylinder, it would represent the 
 actual compressing force to which it owes its density. If the 
 gravitation of the earth were diminished one thousand times 
 this atmospheric column would expand one thousand times,* 
 (taking no account of the decrease of gravitation by increase of 
 distance ;) so that the diameter of the aerial globe would be in- 
 creased to 108,000 miles, taking the atmosphere at 50 miles. 
 But the mere increasing the bulk of the atmosphere 1000 times 
 would increase the diameter to little more than double. Even 
 giving the correct expansion, a comet's mass must be much 
 greater than is generally supposed, or the diameters of the 
 nuclei would be greater if composed of any gas lighter than 
 atmospheric air. 
 
 It is very improbable that a comet is composed of only one 
 elementary gas, and if of many, their specific gravities will 
 vary; the lighter, of course, occupying the exterior layers. 
 With such a small mass, therefore, the upper portion of its at- 
 mosphere must be very attenuated. Now let us remember 
 that the density of the ether at a comet's aphelion, is greater 
 man at the perihelion, in the dirfct ratio of the square roots 
 of the distances from the sun nearly. At the aphelion the 
 comet lingers through half his period, giving ample time for 
 the nucleus to be permeated by ether proportionally dense with 
 the surrounding ether of the vortex at that distance. Thus situ- 
 ated, the comet descends to its perihelion, getting faster and 
 faster into a medium far less dense, and there must consequently 
 be an escape from the nucleus, or in common parlance, the 
 comet is positively electric. This escaping ether, in passing 
 through the attenuated layers composing the surface of the 
 * Prin. Prop, xx Lib. Sec. 
 
MECHANICAL THEORY OF STORMS. 201 
 
 nucleus, impels the lighter atoms of cometic dust further from 
 the centre, and as far as this doubly attenuated atmosphere of 
 isolated particles extends, so far will the escaping ether be ren- 
 dered luminous. It may be objected here, that a contrary ef- 
 fect ought to be produced when the comet is forsaking its peri- 
 helion ; but the objection is premature, as the heat received 
 from the sun will have the same effect in increasing the elas- 
 ticity, as change of density, and the comet will probably part 
 with its internal ether as long as it is visible to the earth ; and 
 not fully regain it perhaps, until after it arrives at its aphelion. 
 Suppose that we admit that a comet continues to expand in the 
 same ratio for all distances, as is laid down for the comet of 
 Encke when near its perihelion ; it would follow, that the comet 
 of 1811, would have a diameter at its aphelion of fifty millions 
 of millions of miles, that is, its outside would extend one thou- 
 sand times further from the sun, at the opposite side to that oc- 
 cupied by the centre of the comet, than the distance of the 
 comet's centre from the sun, at its enormous aphelion distance. 
 Such an absurdity shows us that there is a limit of expansion 
 due to natural causes, and that if there were no radial stream 
 the volume of a comet would be greatest when nearest the sun. 
 But while the comet is shortening its distance and hastening 
 to the sun in the form of a huge globular mass of diffuse light, 
 it is continually encountering another force, increasing in a far 
 more rapid ratio than the law of gravitation. At great dis- 
 tances from the sun, the force of the radial stream was insuffi- 
 cient to detach any portion of the comet's atmosphere ; pres- 
 ently, however, the globular form is changed to an ellipsoid, 
 the radial stream begins to strip the comet of that doubly atten- 
 uated atmosphere of which we have spoken, and the diameter 
 of the comet is diminished, merely because the luminosity of the 
 escaping ether is terminated at the limit of that atmosphere. 
 Meanwhile the mass of the comet has suffered only an in- 
 finitely small diminution ; but if the perihelion distance be 
 
202 MECHANICAL THEOKY OF STORMS. 
 
 small, the force may become powerful enough to detach the 
 heavier particles of the nucleus, and thus a comet may suffer in 
 mass by this denudating process. We regard, therefore, the 
 nucleus of a comet to represent the mass of the comet and the 
 coma, as auroral rays passing through a very attenuated envel- 
 ope of detached particles. The individual gravitating force of 
 these particles to the comet's centre, may be therefore considered 
 as inversely as the squares of the distances, and directly as the 
 density of the particles ; and this density will, according to 
 analogical reasoning, be as the distances or square roots of the 
 distances ; grant the last ratio, and the gravitating force of the 
 particles composing the exterior envelope of a comet, becomes 
 inversely as the 2.5th power of the distances from the comet's 
 centre.* This being the law of the radial stream, it follows, of 
 course, that a comet's diameter is inversely as the force of the 
 radial stream. It must, however, be borne in mind, that we are 
 speaking of the atomic density, and not of density by compress- 
 ion ; for this cometary dust, which renders luminous the escaping 
 ether of the nucleus, must be far too much diffused to merit the 
 name of an elastic fluid. May not the concentric rings, which 
 were so conspicuous in the comet of 1811, be owing to differ- 
 ences in the gravitating forces of such particles, sifted, as it 
 were, and thus arranged, according to some ratio of the dis- 
 tances, by the centripulsive force of the electric coma, leaving 
 vacant intervals, through which the ether passed without be- 
 coming luminous ? This at least is the explanation given by our 
 theory. We may, indeed, consider it possible that the escaping 
 ether, when very intense, might be rendered luminous by pass- 
 ing into the surrounding ether, and, as it became more diffused 
 by radiation, at last become invisible. In this case, as the law 
 of radiation is as the squares of the distances from the centre 
 inversely, the rays would be more and more bejit at right angles, 
 or apparently shortened, as the power of the radial stream in- 
 * With reference to the resisting power of the atoms. 
 
MECHANICAL THEORY OF STORMS. 203 
 
 creased, and the apparent diameters of the coma would be dimin- 
 ished faster than the ratio of the 2.5th power of the distances. 
 But whichever view we adopt, the diameter would again in- 
 crease in the same ratio on leaving the sun, if we make allow- 
 ance for increase of temperature, as well as for diminution of 
 density, for the ordinary distance of a comet's visibility. We, 
 however, regard the change of diameter, as due to both these 
 nodes of action, as best agreeing with the indications afforded 
 by their tails. 
 
 From the preceding remarks, it results that the density of the 
 particles producing the nebulous envelope of a comet, renders 
 the variations of diameter only approximate to the law of the 
 radial stream ; a comet's own electric energy, or the intensity 
 of the escaping ether, may also modify this expression, and 
 many other causes may be suggested. That the radial stream 
 is the cause, in the way we have pointed out, is proved by the 
 positions of the major axis of the short-period comet, making 
 frequently nearly a right angle with the radius vector of the 
 orbit in 1828. A soap bubble gently blown aside, without de- 
 taching it from the pipe, will afford a good illustration of the 
 mode, and a confirmation of the cause. The angles measured 
 by Struve, reckoned from the radius vector, prolonged towards 
 the sun, are subjoined : 
 
 November 7 . . 99. 7 
 November 30 . . 145 .3 
 
 December 7 . . 154.0 
 December 14 . 149 .4 
 
 At this last date, the comet was getting pretty close to the 
 sun. When the angle was greater, as on November 7th, the 
 comet appeared to make almost a right angle with the radius 
 vector ; and in this position of the earth and comet, the longer 
 axis of the elliptical comet was directed to the axis of the vor- 
 tex, as may be verified by experiment. At the later dates, the 
 comet was more rapidly descending, and, at the same time, the 
 axis of the comet was getting more directed towards the earth ; 
 so that the angle increased between this axis and the radius 
 
204 MECHANICAL THEOKY OF STOEMS. 
 
 vector, and consequently became more coincident with it. "We 
 have now to consider the luminous appendage of a comet, 
 commonly called a tail. 
 
 The various theories hitherto proposed to account for this 
 appendage are liable to grave objections. That it is not 
 refracted light needs not a word of comment. Newton sup- 
 poses the tail to partake of the nature of vapor, rising from 
 the sun by its extreme levity, as smoke in a chimney, and 
 rendered visible by the reflected light of the sun. But, how 
 vapor should rise towards opposition in a vacuum, is utterly 
 inexplicable. In speaking of the greater number of comets 
 near the sun than on the opposite side, he observes : " Hinc 
 etiam manifestum est quod cceli resistentia destituuntur."* 
 And again, in another place, speaking of the tail moving with 
 the same velocity of the comet, he says: "Et hinc rursus 
 colligitur spatia coelestia vi resistendi destitui ; utpote in quibus 
 non solum solida planetarum et cometarum corpora, sed etiam 
 rarissimi candarum vapores motus suos velocissimos liberrime 
 peragunt ac diutissime conservant." On what principle, there- 
 fore, Newton relied to cause the vapors to ascend, does not 
 appear. Hydrogen rises in our atmosphere because specifically 
 lighter. If there were no atmosphere, hydrogen would not 
 rise, but merely expand on all sides. But, a comet's tail shoots 
 off into space in a straight line of one hundred millions of 
 miles, and frequently as much as ten millions of miles in a 
 single day, as in the case of the comet of 1843. Sir John 
 Herschel observes, that " no rational or even plausible account 
 has yet been rendered of those immensely luminous appendages 
 which they bear about with them, and which are known as 
 their tails." Yet, he believes, and astronomers generally 
 believe, that a comet shines by reflected light. This theory of 
 reflexion is the incubus which clogs the question with such 
 formidable difficulties ; for, it follows, that the reflecting matter 
 
 * Prin. Lib. Ter. Prop, xxxix., also Prop, xli. 
 
MECHANICAL THEORY OF STORMS. 205 
 
 must come from the comet. But, what wonderful elements 
 must a comet be made of, to project themselves into space with 
 such immense velocity, and in such enormous quantities as to 
 exceed in volume the body from which they emanate many 
 millions of times. This theory may be, therefore, safely 
 rejected. 
 
 From what we have already advanced concerning the coma 
 or nebulosity of the comet, we pass by an easy path to an 
 explanation of the tail. In the short-period comets, the density 
 of the elementary atoms is too great to be detached in the 
 gross from the nucleus, or, rather, the density of the atoms 
 composing the nucleus is too great to permit the radiating 
 stream of the comet carrying them to a sufficient distance to be 
 detached by the radial stream of the sun. Hence, these comets 
 exhibit but very little tails. We may also conceive, that the 
 continual siftings which the nucleus undergoes at each success- 
 ive perihelion passage, have left but little of those lighter 
 elements in comets whose mean distances are so small. Yet, 
 again, if by any chance the eccentricity is increased, there are 
 two causes the density of the ether, and the heat of the sun 
 which may make a comet assume quite an imposing appear- 
 ance when apparently reduced to the comparatively passive 
 state above mentioned. 
 
 According to our theory, then, the coma of a comet is due 
 to the elasticity of the ethereal medium within the nucleus, 
 caused both by the diminished pressure of the external ether 
 near the sun, and also by the increased temperature acting on 
 the nucleus, and thus on the involved ether. The tail, on. the 
 contrary, is caused by the lighter particles of the comet's atten 
 uated atmosphere being blown off by the electric blast of the 
 radial stream of the solar vortex, in sufficient quantities to 
 render its passage visible. It is not, therefore, reflected light, 
 but an ethereal stream rendered luminous by this detached 
 matter still held in check by the gravitating force of the sun, 
 
206 MECHANICAL THEORY OF STORMS. 
 
 whose centre each particle still respects, and endeavors to 
 describe such an orbit as results from its own atomic density, 
 and the resultant action of both the acting forces. From the 
 law of density of the ether, the coma ought to be brightest and 
 the radiating stream of the comet's nucleus strongest on the 
 side of least pressure : from this cause, and the fact that the 
 body of the comet affords a certain protection to the particles 
 immediately behind it, there will be an interval between the 
 comet and the tail less luminous, as is almost invariably ob- 
 served. We thus have an explanation of the fact noticed by 
 Sir John Herschel, " that the structure of a comet, as seen in 
 section in the direction of its length, must be that of a hollow 
 envelope of a parabolic form, enclosing near its vertex the 
 nucleus or head." We have, also, a satisfactory explanation of 
 the rapid formation of the tail ; of its being wider and fainter 
 at its extremity ; of its occasional curvature ; and of its greater 
 length after perihelion than before. But, more especially may 
 we point to the explanation which this theory gives of the fact, 
 that, ceteris paribus, the long-period comets, when their perihe- 
 lion distances are small, have tails of such exaggerated dimen- 
 sions. 
 
 A comet, whose mean distance is considerable, is supposed 
 by the theory to be composed of elements less dense, and, 
 during its long sojourn at its aphelion, it may be also supposed 
 that it there receives continual accessions to its volume from 
 the diffused siftings of the system, and from the scattered debris 
 of other comets. On approaching the perihelion, the rapidity 
 of the change in the density of the ether in a given time, 
 depends on the eccentricity of the orbit, and so does the change 
 of temperature ; so that, from both causes, both the length of 
 the tail and the brilliancy of the comet measurably depends 
 on the magnitude of the period and of the eccentricity. 
 
 If the nuclei of comets be gaseous as we suppose, and that 
 the smallest stars are visible through them, it is an outrage on 
 
MECHANICAL THEORY OF STORMS. 
 
 common sense, to refer that light, which renders a cornet visible 
 at noon-day, within six minutes of space of the sun itself, to the 
 reflected light of the sun. When a small star has been seen 
 through the nucleus of a comet, without any perceptible dimi- 
 nution of light, it indicates perfect transparency ; but there can 
 be no reflection from a perfectly transparent body, and there- 
 fore, a comet does not shine by reflected light. It is true that 
 Arago discovered traces of polarized light in the comet of 1819, 
 and also in more recent comets, but they are mere traces, and 
 Arago himself admits, that they do not permit " the conclusion 
 decidedly that these stars shine only with a borrowed light." 
 But it still does not follow that a comet (even if independent 
 of reflected light) is in an incandescent state. The auroral 
 light is not polarized, nor any other electric light, neither is it 
 owing to a state of incandescence, yet it is luminous. The in- 
 tense light of a comet at perihelion is analogous to the char- 
 coal points of a galvanic battery, caused by a rapid current of 
 ether from the nucleus, and assisted by the radial stream of the 
 vortex. This will account for the phenomenon in all its shades 
 of intensity, as well as for the absence of any perceptible phase. 
 It will also account for the non-combustion of such comets as 
 those of the years 1680 and 1843. We shall also be at no 
 loss to understand, why there is no refraction when a ray of 
 light from a star passes through the nebulosity of a comet; and 
 if, as we may reasonably suppose, the gaseous matter composing 
 the nucleus be very attenuated, instruments are yet too imper- 
 fect to determine whether these also have any refracting power. 
 On this point, however, it is safest to suspend our judgment, as 
 there may be comets not belonging to our system, with even 
 liquid or solid nuclei, or of matter widely different to those 
 elements composing the members of the solar system. 
 
 In addition to what has been already advanced on this sub- 
 ject of a comet's light, we may appeal to the well-known fact 
 that the visibility of a comet is not reciprocally as the squares 
 
208 MECHANICAL THEOKY OF STOKMS. 
 
 of the distances from the earth and sun as it ought to be, if 
 shining by reflected light. In Mr. Hind's late work on comets, 
 the fact is stated that " Dr. Gibers found that the comet of 1780 
 attained its greatest brightness on the 8th of November, thir- 
 teen days subsequent to its discovery, whereas according to the 
 law of reflected light, it should have become gradually fainter 
 from the day of its discovery ; and supposing the comet self- 
 luminous, the intensity of light should have increased each day 
 until November 26th ; yet in the interval between the 8th and 
 26th of that month, it grew rapidly less." Now this theory 
 teaches, that a comet is neither self-luminous nor dependent on 
 the sun, but on its distance from the axis of the vortex, and a 
 certain amount of elapsed time from the perihelion, varying 
 somewhat in each particular case. This fact is therefore a very 
 strong argument in favor of our theory. 
 
 Amidst the many anomalous peculiarities of comets, it has 
 been noticed that a short tail is sometimes seen at right angles 
 to the principal tail, and in a few cases pointing directly towards 
 the sun. Much of this may be owing to perspective, but grant- 
 ing the reality of the fact, it is still explicable on the same gen- 
 eral principles. 
 
 In speaking of the modifying causes which influence the 
 weather, we mentioned the effect due to the position of the sun 
 with respect to the axis of the vortex. This will be found to 
 have a sensible effect on the action of the radial stream. The 
 natural direction of a comet's electric stream is towards the axis 
 of the vortex, and in the central plane of the vortex it will be 
 also towards the sun. But this stream is met by the stronger 
 radial stream from the axis, and as Mr. Hind describes it, "is 
 driven backward in two streams passing on either side of the 
 head, and ultimately blending into one to form the tail." Now, 
 if the body of the sun be situated between the comet and the 
 axis of the vortex, it will shield the comet from the action of 
 the radial stream, and thus a tail may really point towards the sun. 
 
MECHANICAL THEORY OF STORMS. 209 
 
 In 1744 a brilliant comet exhibited six distinct tails spread 
 out like a fan, some seven days after its perihelion passage ; its 
 distance from the sun at the time not being more than a third 
 of the earth's distance. The comet was then rapidly approach- 
 ing the plane of the ecliptic, and if we make the calculation for 
 the position of the sun, we shall find that the body of the sun 
 was on the same side of the axis of the vortex as the comet, 
 and that the comet was then situated at the boundaries of the 
 conical space, enclosed by the radial stream in its deflected pas- 
 sage round the body of the sun. In this position there are nu- 
 merous cross currents of the stream, and hence the phenomenon 
 in question. As this fact rests on the testimony of one indi- 
 vidual, and is an occurrence never recorded before or since, 
 many are disposed to doubt the fact, yet our theory explains 
 even this peculiarity, and shows that there is no necessity for 
 impugning the statement of Cheseaux. 
 
 Another unexplained phenomenon is the corruscation of the 
 tail. It has been attempted to explode this fact also, by refer- 
 ring it to conditions of our own atmosphere ; and it is generally 
 considered the argument of Olbers, founded on the great length 
 of the tail and the velocity of light, is sufficient to prove that 
 these corruscations are not actually in the tail. Now, it is un- 
 doubtedly true, that as light travels less than two hundred thou- 
 sand miles in a second, and a comet's tail is frequently one hun- 
 dred millions long, it is impossible to see an instantaneous mo- 
 tion along the whole line of the tail ; but granting that there 
 are such flickerings in the tail as are described by so many, it 
 must necessarily be, that these flickerings will be visible. It 
 would be wonderful indeed, if a series of waves passing from 
 the comet to the extremity of the tail, should have their phases 
 so exactly harmonizing with their respective distances as to pro- 
 duce a uniform steady light from a light in rapid motion. The 
 argument, therefore, proves too much, and as it is in the very 
 nature of electric light thus to corruscate, as we see frequently 
 
210 MECHANICAL THEORY OF STORMS. 
 
 in the northern lights, we must be permitted still to believe that 
 not only the tails, but also the heads of comets do really cor- 
 ruscate as described. 
 
 With respect to the direction of the tail, astronomers have 
 been forced to abandon the antiquated notion, that the tail 
 always pointed directly from the sun ; yet they still perti- 
 naciously cling to the idea, that although this is not always the 
 case, the tail only deviates from this direction in the plane of the 
 orbit. As this is a most important question, it is necessary 
 formally to protest against such a conclusion. If the earth 
 should happen to be in the plane of the comet's orbit and the 
 tail appears in that plane, it must of course be in that plane 
 really ; but if the earth is not in the plane of the comet's 
 orbit, the tail is not necessarily in the same plane, whatever its 
 apparent direction may indicate. It is true there is a tendency 
 of every particle of the tail, moving under the restraining influ- 
 ence of the sun's attraction, to continue in the plane of the 
 orbit ; and in certain positions there is no oblique action arising 
 from the force of the radial stream to cause it to deviate from 
 that plane ; yet in other positions of the comet, the action of 
 the radial stream may be oblique, forcing it out of that plane, 
 and still such a direction might be assigned to it as to make it 
 conform. In the comet of 1843, P. Smythe observed a forked 
 tail 25 long on March 3d, and from the end of the forked tail, 
 and from its north side, a streamer diverged at an angle of 6 or 
 7 to the north. As this was contrary to the direction of the 
 curvature, if the tail had been curved, it could only arise from 
 a portion being driven off by the radial stream, or bent towards 
 the plane of the ecliptic. The curvature observed by others at 
 a later date, was concave to the south. Towards the middle and 
 close of March, the tail became straight, and with the above ex- 
 ception, might be considered to move in the plane of the orbit. 
 
 The celebrated comet of Halley, as observed by Dr. Bessel 
 in 1835, showed that a more or less well-defined tuft of rays ema- 
 
MECHANICAL THEOEY OF STOEMS. 211 
 
 nated from that part of the nucleus which was turned towards 
 the sun ; and the rays being bent backward formed a part of 
 the tail. The nucleus, with its emanations, presented the 
 appearance of a burning rocket, the end of which was turned 
 sideways by the force of the wind. And, Bessel concludes : 
 " That the cone of light issuing from the comet deviated con- 
 siderably both to the right and left of the true direction of the 
 sun, but that it always returned to that direction, and passed 
 over to the opposite side ; so that the cone of light, and the 
 body of the comet from whence it emanated, experienced a 
 rotatory, or, rather, a vibrating motion in the plane of the orbit" 
 It is impossible that Bessel should here mean that this motion 
 was certainly in the plane of the orbit ; for the orbit was then 
 viewed sideways, and he had no means of ascertaining the fact. 
 His meaning must be that it was apparently in the plane of the 
 orbit. If a plane be made to pass through the earth, the 
 comet, and the sun, the tail might be placed in any position in 
 that plane, and yet appear to be at the intersection of the two ; 
 that is, in the plane of the comet's orbit. The vibration of the 
 tail, in this case, is another strong proof of the correctness of 
 our theory. To make it more intelligible, we shall resort to a 
 diagram. 
 
 In the following diagram, the comet's orbit, represented by the 
 dotted line, is drawn on the plane of the ecliptic ; it is, there- 
 fore, necessary to bear in mind, that it is tilted up from the line 
 of nodes S N, at an angle of 17 45'. The position of the 
 comet, October 9th, is at C, approaching its perihelion ; that of 
 the earth at the same time at T ; while S represents the sun, 
 and S Q the line of equinoxes. Now, from a cause already 
 explained, the tail always tends to lay behind the comet, in the 
 direction indicated by the lower tail in the diagram at 1, and, 
 if produced, would pass to the left of the sun, as seen from the 
 earth : the force of the radial stream, however, will not allow 
 this lagging of the tail, and it is straightened out by this force ; 
 
212 
 
 MECHANICAL THEORY OF STORMS. 
 
 NX" Fi /-* s 
 
 but, being directed to the axis of the vortex, and not to the 
 sun, it is not really in the plane of the orbit, but is seen in the 
 direction of the upper tail depicted in the diagram at 3, and, if 
 produced, would pass to the right of the sun, as seen from T. 
 Now, there is an intermediate position of the tail, in which it 
 will appear in the prolongation of the radius vector S C ; this 
 position is represented by the middle or central tail of the comet 
 at 2, yet this is not in the plane of the orbit, it only appears 
 to be, as may be readily understood by remembering that the 
 earth at this time is under this plane, and the comet is seen at 
 a considerable elevation above the plane of the ecliptic. When 
 the comet's tail becomes directed to the axis of the vortex, or 
 in the apparent position of No. 3, the comet, rapidly careering 
 on its way to the sun, again leaves the tail behind, and again it 
 is strengthened out by the radial stream oscillating about the 
 mean position at 2, as observed by Bessel. From this, it 
 appears, that there is no necessity to make confusion worse 
 confounded, by resorting to polar forces, which are about as 
 intelligible as the foundations of the pillars of Atlas. 
 
MECHANICAL THEORY OF STORMS. 213 
 
 It may be objected that the continued action of the radial 
 stream with that velocity we have contended for, ought to keep 
 the tail invariably directed from the axis of the vortex ; but, 
 where there are two forces or tendencies, as in this case, analogy 
 would teach us that a certain degree of oscillation is a necessary 
 result. There may, also, be slight and transient changes in 
 the direction of the radial stream. In the hurricane there are 
 short and fitful blasts inclined to the general direction of the 
 wind, which must arise from the inertia of the moving mass of 
 atmosphere, causing temporary condensations and rarefractions. 
 Be this as it may, we have assigned a cause which satisfies the 
 phenomenon, without coming into collision with a single 
 principle of celestial mechanics. 
 
 Prof. Struve compared the tail of this comet to a flame, or 
 " ray of fire shot out from the nucleus, as from some engine of 
 artillery, and driven on one side by the wind." At the same 
 time, he saw a second emanation nearly in the opposite direc- 
 tion. This last might arise from a momentary fluctuation in 
 the relative intensities of the electric radiation of the comet, 
 and of the radial stream, owing to the probable irregularities 
 just alluded to. Such and kindred phenomena are utterly 
 inexplicable, without we adopt the theory we are advocating. 
 One other feature, and we will leave the subject. 
 
 From our explanation of the solar spots, we inferred the ex- 
 istence of another large planet in the system. Might not the 
 same effect be produced by a comet ? Or may there not be so 
 many comets, whose great elongation, combined with even a 
 moderate mass, may render t impossible to calculate the posi- 
 tion of the sun with respect .0 the central axis of the vortex, 
 always considering this last as the axis of equilibrium ? In a 
 general way, we might say that the very number of comets in 
 all directions and all distances, would tend to neutralize each 
 other's effects ; but we are not under this necessity. A comet, 
 moving in a parabola, does not belong to the system or to the 
 
214 MECHANICAL THEORY OF STORMS. 
 
 rotating vortex ; and the periodic comets, if of gaseous elements, 
 (as seems so probable,) must, from the size of their nuclei, 
 which the theory considers the only part constituting their 
 mass, have far less mass than the very smallest of the asteroids, 
 and consequently could have very little effect on the mechanical 
 balance of the vortex, even if elongated as far as the orbit of 
 Neptune. Did we know the influence of cold in limiting the 
 expansibility of the elementary gases, we might approximately 
 determine the mass of a comet, from the size of its nucleus ; 
 but this is a problem that has never yet been solved ; and 
 astronomers ought to avail themselves of every indication which 
 promises to realize this great desideratum. The grand comet 
 of 1556 is now probably approaching, and, from recent investi- 
 gations, it appears that it will arrive at its perihelion in 1858, 
 subject to an error either way of about two years. An oppor- 
 tunity may thus be presented of determining the mass of one 
 of the largest comets on record, which may not again occur. 
 This arises from the possible appulse of the comet to the planet 
 Pallas, whose mass, being so small, would more sensibly be dis- 
 turbed by such an appulse than the earth. As the inclinations 
 and ascending nodes of the two orbits approximately coincide, 
 and as Pallas will be near the comet's path, on the approach of 
 the latter to the sun, at the beginning of the year 1857, should 
 the comet become visible about that time, a very close appulse 
 is possible. It is not unlikely, also, that if the elements of 
 Pallas were so far perfected as to afford reliable indications, that 
 the near approach of the comet might thus be heralded in ad- 
 vance, and lead to an earlier detection of its presence. Would 
 it not be a worthy contribution to science, for some one possess- 
 ing the necessary leisure, to give an ephemeris of the planet for 
 that epoch ; as a very slight change in Mr. Hind's elements of 
 the comet, would cause an actual intersection of the two orbits 
 in about heliocentric longitude 153? The subsequent nodal 
 passage of Pallas will take place near opposition, and be very 
 
MECHANICAL THEOKY OF STORMS. 215 
 
 favorably situated for determining the instant of its passage ; and, 
 of all the elements, this would be more likely to be affected than 
 any other.* 
 
 THE ZODIAL LIGHT. 
 
 A phenomenon, akin to that which we have just been con- 
 sidering, is presented by that great cone of diffused light which 
 accompanies the sun, and which in tropical climes displays a 
 brilliancy seldom witnessed in high latitudes, on account of its 
 greater deviation from the perpendicular. Sir John Herschel 
 conjectures that it may be " no other than the denser part of 
 that medium, which, as we have reason to believe, resists the 
 motion of comets, loaded, perhaps, with the actual materials 
 of the tails of millions of those bodies, of which they have been 
 stripped in their successive perihelion passages, and which may 
 be slowly subsiding into the sun." If these materials have been 
 stripped, it is due to some force ; and the same force would 
 scarcely permit them to subside into the sun. Once stripped, 
 these portions must be borne outwards, by the radial stream, to 
 the outer verge of the system. Still r there are, no doubt, denser 
 particles of matter, of the average atomic density of Mercury 
 and Venus, which can maintain their ground against the radial 
 stream, and continue to circulate near the central plane of the 
 vortex, in all that space between the earth and the sun. But 
 
 * In making this suggestion, the author is well aware that Ephemer- 
 idcs of the four chief asteroids have been given annually in the Greenwich 
 Nautical Almanac ; but for the object proposed they are utterly use- 
 less. Will any astronomer contend that these Ephemerides are true to 
 ten seconds of arc ? If not, they are useless for the purpose suggested 
 above, and the theory wants revision. And it is evident that any objec- 
 tion against its practicability, founded on the uncertainty of the number 
 of the asteroids themselves, as has already been urged in answer to this 
 suggestion, is an evidence that the objector weighed the subject in the 
 scales of his imagination only. 
 
216 MECHANICAL THEOEY OP STOEMS. 
 
 if the zodial light be the denser part of that medium, which 
 astronomers now generally recognize as a resisting medium, how 
 happens it that it should be confined to the plane of the eclip- 
 tic ? Why should it not be a globular atmosphere ? Here, 
 again, our theory steps in with a triumphant explanation ; for 
 while it permits the accumulation of such particles around the 
 equatorial plane of the sun, it allows no resting-place very far 
 removed from this plane. The zodial light, therefore, is not the 
 resisting medium, but the passage of the radial stream through 
 a diffuse nebula of atoms, brought down the poles of the vortex 
 by the polar current, and held in check along the central plane 
 by gravitation. 
 
 If these atoms partook of the velocity of the ether, they would 
 not be luminous ; but being held back by gravitation, they are 
 opposed to the radial stream, and hence the light. 
 
 Many stars are also nebulous. In some cases we see the 
 nebulosity edgewise, or along the equatorial planes of the stellar 
 vortices ; in others we look down the poles, and the nebulosities 
 are circular, and there is an endless variety in the shape and 
 intensity of this light. But the universe seems full of motion, 
 and we are not justified in supposing, because a star shows no 
 such light, that it is without rotation. The parallax of the 
 nearest star is only one second, the whole lenticular mass of 
 light which surrounds our sun would therefore only subtend an 
 angle of a single second at the nearest fixed star. Seeing its 
 extreme faintness, therefore, the effulgence of the star would 
 render it totally invisible, provided that it could traverse the 
 vast immensity of intervening space, without feeling the influ- 
 ence of that extinction, which Struve has proved does actually 
 diminish the number of visible stars. 
 
 Corruscations and flickerings have also been noticed in the 
 zodial light, and as usual, the learned have suggested atmos- 
 pheric conditions as the cause, instead of trusting to the evi- 
 dence of their own senses. How prone is philosophy to cling 
 
MECHANICAL THEORY OF STORMS. 217 
 
 to that which is enveloped in the mist of uncertainty, rather 
 than embrace the too simple indications of nature. As if God 
 had only intended her glories to be revealed to a favored few, 
 and not to mankind at large. Blessed will be the day when 
 all will appreciate their own powers and privileges, and no 
 longer regard the oracles which emanate from a professional 
 priesthood, whose dicta have so often tended to darken the sim- 
 ple counsels of truth ! To set the question of pulsations in the 
 zodial light, as well as in the tails of comets, at rest, only re- 
 quires previously concerted observations, in places not very 
 widely apart ; for it is scarcety possible, that atmospheric con- 
 ditions should produce simultaneous pulsations in two distant 
 places. If the pulsations are found to be simultaneous, they 
 are real ; if not simultaneous, they may depend on such con- 
 ditions ; but from the nature of the cause, we should look for 
 them as much in the zodial light, as in the aurora borealis, re- 
 garding the different intensities. 
 
 There is also reason to suspect that the northern side is al- 
 ways the brightest, \>oth in spring and autumn. On the morn- 
 ing of October 4th, 1853, the light was very vivid and well 
 defined, its northern margin grazing Regulus and terminating 
 at Mars, which was also to the north of it. Now, although the 
 northern side was the brightest, the great mass of light was to 
 the south of the ecliptic, as far down as the cone shape was pre- 
 served; but at 10 from the horizon, a still brighter mass pro- 
 truded from the cone towards the north, which was all north 
 of the ecliptic, and of an irregular form, extending along the 
 horizon. The time was 4 A. M., and consequently was not due 
 to any crepuscular light. An explanation of the general fact 
 of the brightest light being always on the north side, is given 
 in the present section, in connection with another phenomenon. 
 If, as some suppose, the light does not reach to the sun, the 
 aunulus must at least fill all the space between Venus and the 
 earth, but it is far more in accordance with facts as well as with 
 
 10 
 
218 MECHANICAL THEOEY OF STOEMS. 
 
 our theory, to suppose it increases in density to the body of 
 the sun. 
 
 Observations made at the observatory of the British Associ- 
 ation, detected, in 1850, sudden brightenings of the light, 
 altogether different from pulsations. The theory would refer 
 these to that fitful irregularity in the momentary intensity of the 
 radial stream, which gives the flickering and tremulous motion 
 to comets' tails. But, the steady variations in the intensity of 
 this light must be due to other causes. The longitude of the 
 sun will here come in as a modifying cause ; for the obstruction 
 caused by the body of the sun, when displaced from the axis 
 of the vortex, must necessarily exercise an influence on the 
 force and direction of the radial stream. A sudden influx of 
 cometary matter down the poles of the vortex, in more than 
 usual quantities, will also tend to brighten and enlarge the 
 zodial light ; and, in this last cause, we have an explanation not 
 only of ancient obscurations of the solar light, but, also, of 
 those phosphorescent mists, such as occurred in 1743 and 
 1831, rendering moonless nights so lighf that the smallest 
 print could be read at midnight. 
 
 In total eclipses of the sun, the denser portion of the zodial 
 light is visible as a brilliant corona ; but, on such occasions, the 
 brightest stars only are to be seen, and, consequently, the fainter 
 portions of the light must be invisible. Hind mentions as 
 many as ten stars visible in the total eclipse of 1842. Accord- 
 ing to the same authority, the color of the corona was like 
 tarnished silver, and rays of light diverged in every direction, 
 and appeared shining through the light of the corona in the 
 total eclipse of 1851. In this year on the day of the eclipse 
 (July 28th), the longitude of the sun was about 340, and, 
 therefore, the body of the sun obstructed the radial stream as 
 seen from the earth on the right side ; but, in 1842, the longi- 
 tude of the sun was, according to our table, about 116, the 
 sun's centre then being 700,000 miles from the axis of the 
 
MECHANICAL THEORY OF STORMS. 219 
 
 vortex, and on the opposite side with respect to the earth ; the 
 position was, therefore, not so favorable for the appearance of 
 these rays which, in many cases, have given the appearance of 
 a whirling motion to the corona. 
 
 At this date, July 7th, 1842, the corona, according to Prof. 
 Airy, ''possibly had a somewhat radial appearance, but not 
 sufficiently marked to interfere with the general annular struc- 
 ture. Mr. Baily, on the contrary, says, the corona had the 
 appearance of brilliant rays ; and, at Milan, long jets of light 
 were particularly noticed. There can be no doubt but that 
 the passage of the radial stream past the outer margin of the 
 moon must also give rise to the same phenomena as when 
 passing the sun, and in this we have an explanation of the 
 fact, that, previous to the moment of first contact, an appear- 
 ance resembling a faintly-illuminated limb of the moon, has 
 been perceived near the body of the sun ; as well as of those 
 flashes of light which have been observed in the lunar disc as 
 the eclipse advances. One important fact, worthy of note, is, 
 that these luminous streaks are more nearly parallel than is due 
 to a radiation from the centre. These streaks have, also, been 
 seen bent at right angles at the middle of their height, as a 
 flame is by means of a blowpipe, precisely analogous to comet- 
 ary rays being driven backwards to form the tail, as already 
 described, thus indicating a common origin. If the moon had 
 an atmosphere, we should, no doubt, see a greater display ; but, 
 having no rotating vortex to protect her from the radial stream, 
 her atmosphere must have been long since stripped off, leaving 
 her exposed to the withering winter blast of the great stream 
 of the solar vortex. In this connection, we may also allude to 
 the appearance of the moon when totally eclipsed. Instead of 
 disappearing at these times, she sometimes shines bright enough 
 to reveal her smallest spots. This has been generally referred 
 to the refraction of the earth's atmosphere bending inwards the 
 solar rays. May it not be owing to the brilliancy of the solar 
 
220 MECHANICAL THEORY OF STOEMS. 
 
 coroDa, which, in 1842, was described as so intense that the 
 eye was scarcely able to support it ? This is a far more palpable 
 cause for the production of this phenomenon, but of which 
 astronomers cannot avail themselves, as long as they are uncer- 
 tain of the origin of this corona. 
 
 SHOOTING STARS. 
 
 The continual influx of cosmical matter into the heart of the 
 vortex in ever-varying quantities, and speedily dispersed along 
 the central plane, according to its density, must necessarily 
 give rise to another phenomenon to which we have not yet 
 alluded. Scarcely a night passes without exhibiting this 
 phenomena in some degree, and it is generally supposed that 
 the hourly average of shooting stars is from five to ten, taking 
 the whole year round. The matter composing these meteors 
 we regard as identical with that mass of diffused atoms which 
 forms a stratum conforming to the central plane of the vortex, 
 and whose partial resistance to the radial stream occasions that 
 luminosity which we call the zodial light. These atoms may 
 coalesce into spherical aggregations, either as elastic gas, or as 
 planetary dust, and, passing outward on the radial stream, will 
 occasionally become involved in the vortex of our own globe ; 
 and being drawn inwards by the polar current, and acted, on 
 by the earth's gravity, be impelled with great velocity through 
 the rarefied air of the upper atmosphere. That meteors are 
 more abundant about the time of meridian passage of a vortex 
 (or, perhaps, more correctly speaking, from six to twelve hours 
 afterwards, when the current of restoration penetrates the 
 atmosphere), well accords with the author's observations. It is 
 about this time that high winds may be looked for, according 
 to the theory ; and it has ever been a popular opinion, that 
 these meteors are a sign of windy weather. Even in Virgil's 
 
MECHANICAL THEOEY OF STOEMS. 221 
 
 time, the same belief prevailed, as a passage in his Georgics 
 
 would seem to indicate. 
 
 " Sape etiam stellas, vento impendente, videbis 
 Praecipites coelo labi ; noctisque per umbram 
 Flammarum longos a tergo albescere tractus ;" 
 
 Virgil was a close observer of nature, and commences a storm 
 with the wind at south, " Quo signo caderent Austri ;" just as 
 we have represented the usual course when these vortices pass 
 near the observer's latitude. It is also a well-known fact, that after 
 a display of meteors, (and we are now speaking of ordinary 
 displays, and not of the great showers,) the temperature falls 
 considerably. It is not uncommon also, that meteors are more 
 abundant during an auroral display, as they ought to be by the 
 theory. We must, however, exempt from this influence those 
 solid meteors which sometimes come into collision with the 
 earth, and afterwards grace the cabinets of the curious. These 
 bodies may be considered microscopic planets, moving in stated 
 orbits with planetary velocity, and bear strongly on the explosive 
 theory of Olbers, as fully detailed by Sir David Brewster. 
 
 It is a very remarkable fact, first noticed by Olbers, that no 
 fossil meteoric stones have yet been discovered. If this fact be 
 coupled with the hypothesis advanced by Olbers, in reference to 
 the origin of the asteroidal group, we should have to date that 
 tremendous catastrophe since the deposition of our tertiary for- 
 mations, and therefore it might possibly be subsequent to the 
 introduction of the present race into the world. May not some 
 of the legendary myths of the ancient world as mystified by the 
 Greeks, have for a foundation the disappearance of a former 
 great planet from the system ? The idea of the existence of 
 seven planets is one of the oldest records of antiquity ; but the 
 earth of course would not be counted one, and therefore in after 
 times, the sun was included to make up the number ; just as 
 the signs of the zodiac have been explained in accordance with 
 the seasons of far later times than we can possibly assign for 
 
222 MECHANICAL THEORY OF STORMS. 
 
 the invention of this division of the heavens. Let those who 
 have the leisure, try how far the contraction and dilation of the 
 asteroidal orbits, to some average mean distance, will restore 
 them to a common intersection or node, as the point of di- 
 vergence of the different fragments. The question is interesting 
 in many of its aspects, and may yet be satisfactorily answered. 
 
 The composition of aerolites may also be taken as indications 
 of the common origin and elementary texture of the planets, 
 whether they are independently formed or have originally per- 
 tained to a former planet ; for no hypothesis of telluric or se- 
 lenic origin yet advanced, can stand against the weight of evi- 
 dence against it. Their fragmentary character rather favors the 
 views of Sir David Brewster, and when we consider that they 
 have been revolving for thousands of years with planetary ve- 
 locity, and in very eccentric orbits, through the ether of space, 
 continually scathed by the electric blast of the radial stream, 
 their rounded angles, and black glossy crust of an apparently 
 fused envelope, may be accounted for, without difficulty, from 
 the non-vitrified appearance of the interior. The composition 
 of aerolites as far as known, embrace nearly one-third of all 
 known simple substances according to Humboldt, and are as fol- 
 lows : iron, nickel, cobalt, manganese, chromium, copper, ar- 
 senic, zinc, potash, soda, sulphur, phosphorus, and carbon. 
 
 The theory we have thus given of the common occurrence of 
 shooting stars, will render a satisfactory general account of their 
 sporadic appearance ; but there are other phenomena of greater 
 interest, viz. : the occasional recurrence of swarms of such n>e- 
 teors, which defy all numerical estimates, being more like a 
 fiery rain than anything they can be compared to. The most 
 interesting feature of this phenomena, is the apparent peri- 
 odicity of their return. In the following table we have set 
 down the most remarkable epochs mentioned by Humboldt, 
 (and no man has devoted more attention to the subject,) as 
 worthy of notice : 
 
MECHANICAL THEORY OF STORMS. 223 
 
 About April 22 to 25 
 
 " July IT to 26 
 
 " August 9 to 11 
 
 " November 12 to 14 
 
 " November 27 to 29 
 
 " December 6 to 12 
 
 Besides these, he mentions two showers, from Arabian au- 
 thority, in October ; one in October, observed in Bohemia ; one 
 observed by himself, in the Pacific, on March 15 ; one Febru- 
 ary 4, just preceding the terrible earthquake of Riobamba, in 
 1797. The Chinese annals also contain many showers of stars, 
 before the present era commenced. Some were in March, more 
 in July, and others in different months. How, then, in view 
 of these numerous dates, can we attach so much importance to 
 the periodicity of these showers ? The great shower of 1833, in 
 the United States, on the 12th and 13th of November, brought 
 to mind the great shower at Cumana, observed by Humboldt 
 and Bonpland just thirty-three years before, to a day ; and it 
 must be confessed that more than ordinary displays have been 
 seen on this date. Yet, on the strength of this, every meteoric 
 shower is supposed to be periodical, and has resulted in a theory 
 which becomes more complicated as the phenomenon is more 
 observed, and can never lead to any useful and practical results. 
 To cite the numerous instances of discrepant results, would only 
 encumber this brief notice with facts neither interesting to the 
 general reader, nor convincing to those who hold a contrary 
 opinion. The author of these pages has watched for many 
 years, and, in view of all the facts, has concluded that the doc- 
 trine of periodicity (as held by present meteorologists) is not 
 tenable. The celebrated August shower failed, also, this year s 
 at least in this place, as for four hours each night, on the 9th, 
 10th, and llth, there were fewer bright meteors than at the 
 close of July. 
 
 Professor Olmsted, who has paid considerable attention to the 
 
224 MECHANICAL THEOKY OF STOKMS. 
 
 subject, has indeed attempted to connect the great November 
 shower with the zodial light, which last he considers a nebulous 
 body, of an elongated form, whose external portions, at this 
 time of the year, lie across the earth's path. (See Silliman's 
 Journal for 1837, vol. xxxiii. No. 2, p. 392.) He even gives 
 its periods, (about six months,) the aphelion of the orbit being 
 near the earth's orbit, and the perihelion within Mercury's. In 
 this way he attempts to explain both phenomena ; but as the 
 zodial light is seen unchanged all the year round in tropical 
 latitudes, it is not the kind of body supposed by Olmsted, and 
 the theory adds nothing to our knowledge. Others have im- 
 agined rings of nebulous matter, in which all the separate parts 
 are moving in the same orbit around the sun, with a retrograde 
 motion, and this, with some modifications, is the current theory 
 of the day. The principal arguments rested on, for the support 
 of this view, are derived from the great shower of 1833, in 
 which a common radiant point was observed, and confirmed 
 subsequently by the radiant of other years, in the same month 
 of November. As this point is almost tangential to the earth's 
 orbit at this season, the earth meets the nebulous ring moving 
 in the contrary direction, and thus confers on these meteors the 
 necessary velocity that is thought to be demanded by observa- 
 tion. 
 
 Now, our theory gives a totally different explanation of the 
 phenomenon. We contend that a retrograde motion of such a 
 nebulous mass, is subversive of our whole theory ; and we must 
 be permitted to examine certain points, hitherto disregarded by 
 those entertaining antagonist views. It is supposed that the 
 meteors in 1833 fell for eight or nine hours. The orbital veloc- 
 ity of the earth is more than 1,000 miles per minute, and the 
 orbital velocity of the nebulous zone must have had a similar 
 velocity. During the nine hours of meteoric display, therefore, 
 the earth traversed 500,000 miles of her orbit, which would give 
 1,000,000 miles for the depth of the nebulous stratum. But if 
 
MECHANICAL THEORY OF STORMS. 225 
 
 of such vast extent, how happened it that the only part of the 
 earth in which these were visible in great density, was the 
 United States, or a space embraced between the latitudes of 50 
 and 20 north, and the longitudes 60 and 100 west, (and 
 these are the widest limits,) comprising only -fa of the surface 
 of the globe ? To a calm inquirer, this difficulty seems insur- 
 mountable. The author was then in the Mediterranean, on 
 deck the greatest part of the night, the weather fine, and 
 nothing unusual visible in the heavens ; from other sources he 
 has also derived similar information. Yet, were the earth then 
 passing through a stratum of meteors 1,000,000 miles in ex- 
 tent, it is utterly inconceivable that other portions of the earth 
 escaped. Much stress is also laid on the fact that these meteors 
 in 1833, passed from east to west generally, as they ought to do, 
 if tangential to the earth in her orbit ; but on the same phe- 
 nomenon occurring in 1799, when the earth was in precisely the 
 same part of her orbit, Humboldt says distinctly, " the direction 
 (of the meteors) was very regular from north to south." How 
 could this possibly happen, and at the same time be moving 
 tangentially to the orbit ? 
 
 There is also another fact of importance not duly weighed in 
 forming such a theory. In 1833 the meteors evidently differed 
 in velocity ; one class, consisting of luminous points, passed like 
 a shower of fire with great velocity to the westward, another 
 class were like large fire-balls with luminous trains moving with 
 less rapidity, while a third class consisted of nebulous patches 
 which remained stationary for a long time, and frequently 
 emitting large streams of light. These last, at least, do not de- 
 port themselves as planetary bodies moving 2,000 miles per 
 minute. But the fact still remains, that unusual displays have 
 occurred about the 12th and 14th of November ; and also as a 
 general thing when there are no unusual displays, the meteors 
 are more abundant about this time. Let us try if we can recon- 
 cile these facts with the theory of vortices. 
 10* 
 
226 MECHANICAL THEOKY OF STOEMS. 
 
 We will first confine our remarks to the increased number 
 of meteors about November 12th and 14th. The cosmical 
 matter composing the zodial light, or at least the lighter parts 
 of it, is continually driven outwards by the radial stream, just 
 as the matter of a comet's tail is stripped from the nucleus. 
 This matter becomes involved in the terral vortex by descend- 
 ing the poles, and is again passed out along the equatorial 
 plane. The form of the zodial light, as seen edgewise, gives a 
 lenticular form for the stratum of planetary particles composing 
 it, and its central plane has been considered as coinciding with 
 the plane of the sun's equator. At the orbit of the earth, this 
 lenticular space is narrowed to a very thin stratum, but un- 
 doubtedly reaches beyond the earth's orbit with a rapidly 
 diminishing density. As the axis of the sun is inclined about 
 7 to the ecliptic, and the ascending node is in the 20th degree 
 of Gemini, the earth can only pass through the plane of the 
 sun's equator about the 12th of December and the 12th of 
 June. If, therefore, the central plane of the vortex coincides 
 with the plane of the sun's equator, meteors ought to be more 
 numerous about the dates above mentioned. But the observed 
 times are on November 12th and 13th. Now, from actual 
 measurements, a computation has been made by M. Houzeau, 
 that the elements of the zodial light are materially different 
 from those of the sun's equator. He fixes the node of the light 
 (according to Mr. Hind) in 2 heliocentric longitude, subject to 
 an uncertainty of 12 or 13, and its inclination to the plane 
 of the ecliptic, 3 35', subject to an uncertainty of about 2. 
 The truth is, astronomers have argued the coincidence of the 
 two planes from considerations connecting the zodial light with 
 the sun's equator, as if it were a solar atmosphere ; but such 
 an atmosphere is impossible, and it is high time such measures 
 should be taken as will lead to some certain conclusion. If in 
 the present state of the question, we were to take the mean, we 
 should find the node in about longitude 40, which is the posi- 
 
MECHANICAL THEORY OF STORMS. 227 
 
 tion of the earth on November 2d. But in the absence of 
 measurements, we will assume, for the sake of argument, that 
 the ascending node of the central plane of the vortex was, in 
 1833, in 50 heliocentric longitude, and consequently the earth 
 was passing through the meteoric stratum or central plane of 
 the zodial light, on the night of November 12th. The opposite 
 period of the year is May 12th a date, it is true, on which no 
 great shower of stars is recorded, but sporadic meteors are very 
 plentiful at that time, and what is more important to observe 
 is, that the llth, 12th, and 13th of May, are the three noted 
 cold days which we have before mentioned. Thus truly indi- 
 cating that the earth is then in or near the central plane of the 
 vortex along which the radial stream is at its maximum of 
 power at any given distance from the axis. 
 
 But the question occurs, does the node of this plane remain 
 stationary, and is there no variation of the inclination of the 
 axis of the solar vortex? We have found from observation, 
 that the axis of the terral vortex is continually oscillating about 
 a mean position by the action of the moon; and reasoning 
 from this analogy, and the constant tendency of a material 
 vortex to preserve a dynamical balance, the same tendency must 
 obtain in the solar vortex under the action of the great planets, 
 whose orbits do not coincide with the central plane of the vor- 
 tex. The ascending node of Jupiter's orbit is in longitude 98, 
 Saturn's 112, Uranus' 72, Neptune's 131 ; so that this plane 
 does not correspond with the plane of greatest inertia discovered 
 by La Place, and from the non-coincidence of these planes with 
 the central plane of the vortex, must produce the same oscil- 
 lation in the axis of the solar vortex, as the moon does in the 
 terral vortex, but to what amount, observation can alone deter- 
 mine. Jupiter and Saturn will of course exert the greatest 
 influence, and when these two planets are in conjunction, the 
 ascending node of the central plane of the vortex will vary in 
 longitude perhaps sufficiently to bring the meteoric maximum 
 
228 MECHANICAL THEOEY OF STOEMS. 
 
 at the ascending node into October on the one hand, and to the 
 close of November on the other, and at the descending node to 
 April 25th on the one hand, and the close of May on the other. 
 The great showers of stars which have been recorded, must 
 be therefore considered as an accidental exaggeration of a per- 
 ennial phenomenon, attaining its maximum when the earth 
 passes through the central plane of the vortex, whose ascending 
 node in 1833 we will suppose was in longitude 50. This 
 theory will therefore account for those great showers which 
 have occurred about the 24th of April, as well as those occur- 
 ring in October and November ; for it is far more consonant to 
 all analogy, to suppose the influx of planetary atoms into the 
 solar vortex to be in irregular, than in regular quantities. Yet, 
 whether in the one case or in the other, the matter will pass 
 along the central plane of the vortex, either diffusely scattered 
 or in denser clouds, and will be encountered by the earth when 
 near the nodes more frequently than at other times. The phe- 
 nomenon of 1833, may then be attributed to the earth encoun- 
 tering an unformed comet on the 12th of November; but we 
 must reflect, that the medium of the vortex is also in motion, 
 and the cometary matter drifting along with it ; and that this 
 motion corresponds with the earth's motion. By becoming in- 
 volved in the terral vortex, it will in a measure be carried along 
 with the earth in her orbit as a temporary occupant of the 
 terral vortex. But we are here met with the objection that the 
 radiant being nearly stationary amongst the stars, demonstrated 
 conclusively, that the source of these meteors did not partake 
 of the earth's motion. There is no difficulty in this. We sup- 
 pose as a general thing, that the meteors descended to the sur- 
 face of our atmosphere down the axis of the vortex (at least in 
 the greatest numbers), and the geocentric longitude of this axis 
 was nearly the same during the whole time of the display. We 
 say nearly, for the motion of the moon in her orbit in nine 
 hours, would change the longitude of the axis three or four de- 
 
MECHANICAL THEORY OF STORMS. 229 
 
 grees, and this is about the change in the position of the ra- 
 diant noted at the time. This objection, therefore, falls to the 
 ground ; for the axis of the vortex, although carried along with 
 the earth in her orbit, was unaffected by the earth's rotation, 
 and would therefore appear nearly as stationary in the heavens 
 as Gamma Leonis. But it is again urged, that the moon was 
 near conjunction with the sun, and consequently the central 
 vortex was on the opposite side of the globe. This is true ; but 
 the outer vortex must have been near the meridian about three 
 hours after midnight, or about the time when the radiant was 
 vertical and the display the greatest. When the axis was to 
 the eastward, the stars would shoot westward, when on the 
 meridian, they would pass in all directions, but principally to 
 the south, on account of the inclination of the axis of the vor- 
 tex ; but this would only be true for places situated to the 
 southward of the central latitude. During the great shower of 
 stars seen by Humboldt, in Cumana, the direction was to the 
 south uniformly. Now, the latitude of Cumana is above 10 
 north, yet still too low for the general limits of the vortices ; 
 but from the same inclination of the axis (from 30 to 36 to 
 the surface), the meteors would pass far south of the limit, and 
 might even reach to the equator. The latitude of the outer 
 vortex ascending on November 12th, must have been near the 
 line of greatest display, from the position of the moon at the 
 time. We thus see why the phenomenon was limited to so 
 small a fraction of the earth's surface; why these meteors 
 should be intermingled with nebulous patches stationary in the 
 heavens for an hour together, and why, notwithstanding these 
 facts, they were independent of the earth's rotation. 
 
 We have yet another objection to answer, viz. : the planetary 
 velocity of some of these bodies. Let us be understood. The 
 velocity of a solid aerolite is due to gravitation, and is planetary, 
 on the other hand, voluminous collections of cometary dust 
 united by accident, and remaining so by mere inertia, are borne 
 
230 MECHANICAL THEOEY OF STORMS. 
 
 passively on the ethereal currents with electric velocity, and 
 probably never penetrate far, even into the attenuated atmos- 
 phere, which may be supposed (from the facts connected with 
 the aurora) to extend far above the denser stratum which re- 
 fracts and reflects light, and from which the assigned limits of 
 our atmosphere have been derived. 
 
 It is generally considered that sporadic meteors are more 
 numerous in the summer and autumn than in the winter and 
 spring, and we have, likewise, in the tenth of August, a date 
 which corresponds to many great displays and meteoric showers, 
 both in recent and remote times. This would seem to vitiate 
 our theory ; for we cannot suppose that there are two central 
 planes in the vortex intersecting the ecliptic in longitude 320 
 and 50. We must remember, however, that as these great 
 displays are accidental, and as the stratum composing the zodial 
 light is manifestly of sufficient thickness to envelope the whole 
 orbit of the earth, that it does not necessarily follow that the 
 dense portions to which meteoric showers are due, should be 
 always confined to the central plane of the vortex. And, 
 besides, we have similar displays recorded in other months, 
 which invalidates the theory of a regularly-recurring phenom- 
 enon. We shall, therefore, only aim at explaining why meteors 
 are generally more abundant in summer and autnmn than in 
 the opposite seasons. 
 
 The axis of the solar vortex, considered as cylindrical, must 
 be admitted to run out to a great depth on either side from the 
 sun, and reach far into that unoccupied space intervening 
 between our system and the nearest fixed stars, and from these 
 opposite points the solar vortex is supplied with that stream of 
 ether which passes down either pole to restore a partial 
 equilibrium in the density of the ether of the vortex, rarefied 
 by centrifugal force. As certain portions of the heavens are 
 crowded with stars, and other parts comparatively vacant, we 
 may expect a similar inequality in the distribution of that 
 
MECHANICAL THEORY OF STORMS. 231 
 
 cometic dust, which causes a certain amount of extinction in 
 the light of the stars, and, therefore, seeing that the two 
 extremities of the axis of the solar vortex are so widely sepa- 
 rated, it would not be wonderful if different quantities of such 
 matter were brought down into the vortex from these extrem- 
 ities. 
 
 From recent observations made by H. R. Birt, at the observ- 
 atory of the British Association, it would appear that the 
 brightest portion of the zodial light is always north of the 
 ecliptic. Others have also remarked the same, and if we couple 
 this fact with the suggestion just made, we are justified in sus- 
 pecting that a greater quantity of cornetic dust comes down 
 the northern pole of the vortex than down the southern. This 
 matter, in passing outward, does not, of course, immediately 
 attain to the central plane of the vortex, but is more thickly 
 distributed along a plane parallel to this plane. And the same 
 will be observed by that matter coming down the southern 
 pole ; it will be, in a certain degree, retained in a plane south 
 of the central plane, but still parallel with it. This would 
 account for the greater brightness of the northern side of the 
 zodial light. It would, also, account for the greater frequency 
 of meteors in summer and autumn than in the opposite seasons 
 From May to November the earth is above the central plane of 
 the vortex, and, consequently, on the northern side ; but after 
 passing the node in November, she is on the under or southern 
 side, and the meteors are less frequent. With this general 
 explanation we shall close. If what we have advanced be an 
 approximation to the truth, the theory itself affords ample 
 indications of what observations are requisite to prove or dis- 
 prove it ; and, on this account, a theory is of great benefit, as 
 suggestive of many questions and combinations of facts which 
 otherwise might never be thought of. 
 
 We have thus taken a cursory glance at the prominent 
 physical phenomena of the world, and attempted to link them 
 
232 MECHANICAL THEOKY OF STORMS. 
 
 together in the bonds of one all-pervading principle. We have 
 fearlessly taken a new path, and claim originality for the whole, 
 disclaiming all intention of retailing second-hand wares, or of 
 compiling an ingenious theory from heterogeneous scraps. If 
 it be true, or if it be partially true, let those professionally 
 engaged in such pursuits enter the wide field of investigation 
 we have discovered for them ; for if the whole theory be true, 
 it only shows in a clearer light that the great work which has 
 been fancied so near completion is scarcely yet begun ; while 
 the prospect of an ultimate and final completion of the temple 
 which so many zealous votaries are erecting, is rendered mourn- 
 fully hopeless by the contemplation of what yet remains to be 
 performed. 
 
SECTION SIXTH. 
 
 THE POLAR ICE. 
 
 WE shall conclude these pages by again referring to our 
 theory of the weather, in connection with an event which every 
 friend of humanity and every lover of natural science is bound 
 deeply to deplore. 
 
 From the present position of the lunar nodes and apogee, the 
 vortices of our earth do not ascend into very high latitudes. 
 Now, according to the principles laid down, the frequency of 
 storms tends to lower the temperature in the warm regions of 
 the earth, and to elevate it in the polar regions. Let us sup- 
 pose the northern limit of the vortices to be in latitude 70. 
 There will be, in this case, a greater prevalence of northerly 
 winds within this circle of latitude, to supply the drain to the 
 southward, and the back currents by passing above will de- 
 scend at the pole, partaking of the temperature due to that ele- 
 vation. The character of the arctic seasons may therefore be 
 considered as partly dependent on the average direction of the 
 wind. Suppose again, the extreme limits of the vortices to be 
 about latitude 80, the relative areas of the two circles are as 
 4 to 1 ; so that in this last case the exclusive range of the 
 northerly winds is limited to one-fourth of the first area. South of 
 80 the wind will frequently come from the south, and by mixing 
 with the local atmosphere of that latitude, will tend to amelio- 
 rate the small area to the northward. And the greater atmos- 
 
234 MECHANICAL THEOEY OF STOEMS. 
 
 plieric commotion when confined to such a small circle of lati- 
 tude, must assist materially to break up the polar ice ; which 
 would tend still more to equalize the temperature. 
 
 By referring to our table, we see that the mean conjunction 
 of the pole of the lunar orbit and the moon's apogee, was in lon- 
 gitude 128 on April 10, 1846, and let it be remembered that 
 when the conjunction takes place due south or in longitude 
 270, the vortices attain their greatest latitude north. When, 
 on the contrary, the conjunction takes place due north or in lon- 
 gitude 90,* the northern limits of the vortices are then in the 
 lowest latitude possible. 
 
 Sir John Franklin sailed in May 1845, and was certainly at 
 the entrance of Wellington sound, near latitude 75, April 3d, 
 1846, as the dates on the graves testify. That season, according 
 to the theory, was a cold one ; for the vortices could not reach 
 so far to the northward in that year, and consequently there 
 were no storms, properly speaking. It would probably be late 
 in the summer of 1846, before the expedition was liberated, 
 and as the prevailing winds would be from the northward, he 
 would have little choice, but to stand to the westward if the 
 state of the ice permitted. In his instructions he was to use 
 every effort to penetrate to the southward and westward of 
 Cape Walker, and he probably conformed to them under the 
 circumstances, and passed the winter in the ice, in that neigh- 
 borhood. And in 1847 we do not anticipate, from the theory, 
 that he would make much progress westward. 
 
 In 1848, Sir James Ross was sent out with the first relief- 
 ship ; but was not able to reach the entrance of Wellington 
 channel because of compact ice from there to Leopold Island. 
 This was about the beginning of September a time when the 
 northern channels are usually the most open. On the llth, 
 they ran the ships into Port Leopold, and the next day the ice 
 
 * The reader will of course understand these as celestial longitudes, 
 and the latitudes as terrestrial. 
 
MECHANICAL THEORY OF STORMS. 235 
 
 shut them in for the winter. From the character of the season, 
 we may infer that if Franklin did not enter Wellington channel 
 in 1847, as is most probable, neither did he in 1848. Perhaps 
 he was not able to get his ships far to the westward, as we infer 
 from the theory. Still, as the time was not very protracted, he 
 would wait patiently another season and husband his resources. 
 
 In 1849, Sir James Ross cut his ships clear of the ice Au- 
 gust 28th, and crossed over to Wellington channel, where he 
 found the land-ice still fast, showing that this season was also a 
 bad one in accordance with the theory. On the 1st of Sep- 
 tember he met the first gale of wind, at which time the Inner 
 Vortex was at its extreme north latitude, and rapidly extending 
 its limits by the motion of the perigee. 
 
 This vortex describes a smaller orbit than either the central 
 or the outer vortex, and consequently reaches into higher lati- 
 tudes. But the time was badly chosen, as the whole series of 
 years since Franklin left has been unfavorable for the early rup- 
 ture of the ice. Sir James Ross having been drifted out of 
 Lancaster sound by the gale, finally bore up for England to- 
 wards the close of September 1849. 
 
 The same year, the North Star with additional supplies was 
 working up Baffin's bay ; but on account of the unusual quan- 
 tities of ice, and the frosts " which glued the floes together," she 
 was unable to force a passage through the middle ice, and win- 
 tered on the east side of Baffin's bay, in latitude 76 33' her 
 thermometer marking 64 below zero, as the coldest of the win- 
 ter. In 1850, the perigee of the moon attained its northern 
 limit, but the position of the node was bad ; still this year and 
 1851, were the best of the series. The North Star succeeded 
 in getting out of the ice on the 1st of August a very early 
 date for that high latitude and on the 8th had crossed over to 
 Possession bay ; but being prevented by the land-ice, she bore 
 up for Pond bay and there landed the provisions. The same 
 year (1850) several vessels entered Lancaster sound. Sir John 
 
236 MECHANICAL THEOKY OF STOEMS. 
 
 Ross also reached Melville Island ; from which it is evident that 
 this season was far better than any preceding. According to 
 Captain Penny, this year a floe of ice at least two years old, 
 filled Wellington strait ; but was diminished in breadth at a 
 subsequent visit. He also saw a boundless open sea from the 
 western entrance of Wellington strait ; but of course the ships 
 could not reach it, for the floe before mentioned. Following 
 the indications of the theory, we consider it almost certain that 
 Franklin went to the westward and not through Wellington 
 channel; that he made but slow progress until 1850, when 
 finding the sea more open to the northward, and attributing it 
 more to local influences than to any change in the season, he 
 considered it a better course to extricate the expedition, by push- 
 ing on towards Behring's straits than to attempt the frozen 
 channels he had already passed through. But the seasons 
 again getting worse after 1850, he was again arrested in the 
 polar basin by the ice and islands off the northern coast of 
 America. 
 
 Regarding the old and new continents as in reality a con- 
 nected body of land, with a polar depression, we may expect 
 that the great range of American mountains is continued in a 
 straight line, from the mouth of the McKenzie river, obliquely 
 across the Polar sea, and connects with the Ural; and that 
 along the axis of the chain, protuberant masses will emerge 
 above the sea level, constituting an archipelago of islands, from 
 Nova Zembla to the McKenzie ; and that these islands, causing 
 an accumulation of ice, and arresting its general tendency to the 
 southward, is the barrier which Sir John Franklin was finally 
 stopped by, in a situation where he could neither advance nor 
 return. With the map before us, and the data afforded by 
 former voyages, and guided by these theoretical views, respect 
 ing the prevailing direction of the winds and the character of 
 the seasons, we should locate Sir John Franklin near latitude 
 80, and longitude 145, in 1851 ; and as the seasons would 
 
MECHANICAL THEOEY OF STORMS. 237 
 
 afterwards become more severe, we may consider that he has not 
 been since able to change his locality, and dare not desert his 
 ships.' 
 
 No mere stranger can feel a deeper interest than the author, 
 in view of the hard fortunes of these hardy explorers, and he 
 would not lightly advance such opinions, did he not suppose 
 they were in some degree reliable. In 1832, he himself crossed 
 the Atlantic, for the purpose of offering himself to the Geo- 
 graphical Society of London, intending to be landed as far north- 
 ward as possible, with a single companion,* from which point 
 he purposed to follow the coast line on foot, with cautious dis- 
 cretion as to seasons, confident that, with arms and ammunition, 
 he could support himself for many years. It has always been a 
 grave error in all these northern land expeditions, that they 
 have been too unwieldy, too much encumbered with the com- 
 forts and luxuries of civilization at the outset, and too much 
 loaded with a philosophical paraphernalia, for a pioneering sur- 
 vey, and cherishing too fondly the idea that the wide shores 
 of the Arctic sea could be explored in a single season. Had the 
 British government established a few posts in the Arctic regions 
 in the beginning, one, for instance, in Lancaster sound, another 
 in Behring's Straits, and a third near the mouth of the Cop- 
 permine, volunteers of sufficient scientific attainments might 
 have been procured, to banish themselves to these inhospitable 
 regions for a term of years, if assured of triennial supplies ; and 
 in this way, by summer boat-parties and winter expeditions, 
 over land or ice, the explorations could have been gradually ex- 
 tended, and a greater knowledge of the polar regions might 
 have been acquired, with an immense saving both of life and 
 money. In 1832 the author's plan was deranged, by finding 
 that Captain Back was about setting out in quest of Ross, wh'o 
 had then been some four years absent. This officer had all his 
 party engaged when the author waited upon him in Liverpool, 
 * Mr. William McDonald, of Canada. 
 
238 MECHANICAL THEOKY OF STORMS. 
 
 and no notice was taken of a modified plan which he forwarded 
 to the Society at his suggestion. It was therefore abandoned. 
 
 The above fact is alluded to, in order to show the author's 
 sincerity in expressing his belief that, with a previous prepara- 
 tion of mind and body for a sojourn in those frigid climes, a 
 sufficient subsistence may be derived from the country itself. 
 Advantage must, of course, be taken of the times of abundance, 
 and due preparation made for the season of scarcity. Averaging 
 the extremes, there is little doubt but that both land, and air, 
 and water, afford an abundance of food for man in the Arctic 
 zone, and that, when spurred by necessity, it is within his power 
 to obtain it. We ought not therefore to despond, or give up 
 efforts to rescue those who have well earned the sympathy of the 
 world, by what they must have already suffered. These northern 
 seas will yet be explored. The very difficulty of accomplishing 
 it, will itself give it a charm, which in this restless age will 
 operate with increasing power. And should efforts now be re- 
 laxed, and in some future time the evidence be brought to light 
 that some of the party yet existed, long after all efforts to rescue 
 them had been abandoned, the fact would be a dark spot on 
 the escutcheon of England, which time could not erase. 
 
 Since these pages were written, accounts have been received 
 from Captain McClure, of H. M. ship Investigator, which fully 
 confirm the preceding remarks on the character of the seasons 
 in the Arctic circle ; and, more recently, despatches have been 
 received from the discovery-ship, Amphy trite, in relation to the 
 past season in Behring's straits, which also confirms the theory. 
 
 The Investigator (now supposed to be frozen up in lat. 74 
 5' N., and long 117 54' W., the last despatch being dated 
 April 10, 1853) passed round the northern shores of America 
 into the channels communicating with Lancaster sound, in 
 1850, but was unable to extricate herself in 1852, and, prob- 
 ably, yet remains in the harbor she made in the winter of 1851, 
 in the position above named. No trace of Sir John Franklin's 
 
MECHANICAL THEOKY OF STORMS. 239 
 
 expedition was, however, found, and, indeed, according to our 
 theory, the Investigator was not on the most promising ground. 
 We contend that Franklin has penetrated the pack of appa- 
 rently perennial ice, which is continually pressing to the south- 
 ward, and blocking up the passages between the northern 
 islands, or skirting the coast line of the continent ; which pack 
 has since increased, and effectually stopped all egress from the 
 open central portions of the polar sea. If Sir John Franklin 
 is ever heard from, this pack must be penetrated, and a powerful 
 steamer ought to be sent immediately by the British government, 
 to be ready in Behring's straits early enough to take advantage of 
 the first openings, and make a bold push due north, so as to 
 get as speedily as possible into the open waters to the north of 
 the pack. 
 
 If the author could make himself heard at Washington, he 
 would also urge the government to lose no time in following 
 our own expedition under Dr. Kane, who, if he finds a clear 
 entrance from Smith's sound into the Arctic sea, may be 
 induced to push on, and endeavor to make his way through 
 the pack towards Behring's straits, and thus fall into the same 
 snare as Franklin. According to the theory, the higher the 
 passage into the Arctic sea, the less will it be incumbered with 
 ice, and, consequently, Smith's sound is the best both to enter 
 and return by ; and had the author not already smarted enough 
 by having his professions derided, he would have submitted 
 these views to the patrons of that expedition before it sailed. 
 
 The scientific world is, in reality, chargeable with the disas- 
 trous results of Franklin's expedition. The polar basin is 
 hemmed in by the coast line of Europe, Asia, and America, in 
 about latitude 70 north, for the greatest part of the entire 
 circumference. And this coast line, and the islands adjacent, 
 will cause the polar ice to accumulate and form a frozen belt 
 along these shores, in consequence of the constant tendency of 
 the earth's rotation to press the ice to the southward. The 
 
240 MECHANICAL THEOKY OF STOEMS. 
 
 fact that an open passage exists between this belt and the shore 
 in summer time, is no objection, as the tides, river currents, 
 and warm land breezes, may very well explain this. The learned 
 have insisted, and do yet insist, that the earth's rotation can 
 produce no motions in the Arctic sea, and, under this delusion, 
 Franklin has passed into the comparatively open waters inside 
 the pack, perhaps has lost his ships ; yet it is very possible that 
 the party may have escaped, and derived a subsistence from 
 the more genial waters of the central portion of that ocean 
 unto this day. 
 
 We have already alluded to the difference of level between 
 the Atlantic and Pacific waters. It is well known that the 
 currents in the Spitsbergen and Greenland seas is to the south- 
 ward, and that Parry, in his attempt to reach the pole, was 
 foiled by this very current, frequently setting him back in 
 twenty-four hours more than his party could travel in the same 
 time over the ice. Through Baffin's and Hudson's bay the 
 northern waters are also continually bearing their frozen freight 
 southward. We are, therefore, entitled to ask, what supplies 
 this immense drain? Behring's straits are only about sixty 
 miles wide, and twenty-five fathoms deep ; the supply, therefore, 
 through this channel is totally inadequate, yet there is no other 
 channel into the Arctic sea where the current is inward. We 
 have already explained the reason why the current through 
 Behring's straits is an exception to the general rule, yet still 
 confirming the principle by referring it to the configuration of 
 the land enclosing the Pacific ocean. The whole south Pacific 
 lies open to the pole, and the inertia of the immense mass of 
 mobile waters pressing northward, and continually contracted 
 by the form of the American and Asiatic coasts, is not balanced 
 by a contrary impulse of the waters of the north Pacific, inas- 
 much as this ocean becomes narrower as it extends northward, 
 and the only passage to the frozen ocean is through the narrow 
 straits of Behring. The axifugal force of rotation due to the 
 
MECHANICAL THEORY OF STOEMS. 241 
 
 northern waters is, therefore, overborne by the vast preponder- 
 ance due to the southern waters, and, hence, the northern 
 Pacific may be considered as relatively at a higher level, and 
 there will be a current northward through Behring's straits, as 
 we find it. The same cause accumulates the waters under the 
 equator, thus giving a higher level to the Pacific than to the 
 Atlantic at the isthmus of Panama, where the difference of 
 level is found by actual measurement to be five or six feet. 
 This fact has never before been explained ; but the cause is too 
 obvious to admit of question. 
 
 That the sea is deeper than was formerly admitted, is now 
 fully confirmed. We have before alluded to the results obtained 
 by Captain Denham, of H. M. ship Herald, who found bottom at 
 7, TO 6 fathoms, or about nine English miles. Now, whether 
 that spherical shell, which we have contended to be the true 
 form of the solid earth, be continuous and entire; or, whether 
 it may not be wanting in localities of limited extent where the 
 ocean would be absolutely unfathomable, we know not ; but if 
 such be the internal constitution of our globe, there will be, no 
 doubt, many channels of communication between the internal 
 and external ocean, and, as a consequence of the earth's rota- 
 tion, the axifugal current of the Arctic sea may be supplied by 
 an upward current from the interior of the globe; and this 
 current may have a higher temperature than the surface waters 
 of that sea, and thus the middle portions may, in truth, remain 
 open the whole year round, and be teeming with animal life. 
 According to Captain Penny's observations in 1850, whales and 
 other northern animals existed to the westward, where he saw 
 the open sea stretch out without a bound before him. 
 
 It has been a question mooted by some, that Franklin's ships 
 might be overtaken, at an early stage of the voyage, by a storm, 
 and foundered amidst the ice. The theory would give a nega- 
 tive answer to this question. Stiff gales may prevail far to 
 the north when the vortices do not reach so high ; but no 
 11 
 
242 MECHANICAL THEORY OF STORMS. 
 
 storm, properly speaking, will be found far beyond their north- 
 ern limit. After the coming winter (1853), the vortices will 
 gradually penetrate farther and farther to the northward, and 
 the years 1857, 1858, and 1859, will be highly favorable for 
 northern discovery, accompanied, however, with the necessary 
 draw-back of tempestuous weather. 
 
 CONCLUSION. 
 
 Our theory has thus extended itself beyond those limits 
 which we at first had drawn, and our apology must consist in 
 the necessity existing for reconciling the most remarkable phe- 
 nomena of meteorology to its principles. Yet, after all, what 
 has been said is but an outline of what remains, but this outline 
 is a part of our theory of the weather, and it could not well do 
 without its aid. In some points we may not have correctly in- 
 terpreted facts ; but the facts remain. The numerical elements 
 of the theory may also be in error we know not; but we 
 think that they are as perfect as the many contingencies on 
 which they depend will permit. What is certain, however, is 
 of ample value to compensate for trivial errors. We have 
 hitherto -experienced but little courtesy from those intrusted 
 with the keys of knowledge, and cannot consequently anticipate 
 a very lenient verdict. But we now tell them before the world, 
 that they have a duty to perform, and an examination to make, 
 and a decision to come to, " whether these things are so." Our 
 theory may be called an ingenious speculation, but WE CHAL- 
 LENGE THE SCIENTIFIC TO PROVE IT NOTHING 
 ELSE. The theory furnishes them with tests of daily occur- 
 rence, to prove or to disprove it. By such a trial we are willing 
 to be judged ; but let it be conducted in the spirit recommended 
 
MECHANICAL THEOKY OF STORMS. 243 
 
 in the opening address before the American Association for the 
 Advancement of Science, to expose all false developments, and 
 to do it generously and without prejudice; and to remember, 
 "that the temple of science belongs to no country or clime. 
 It is the world's temple, and all men are free of its communion. 
 Let its beauty not be marred by writing names upon its walls."* 
 The great objection, of friction and resistance of an all-pervading 
 medium, which will be urged against it, we regard as rather 
 the offspring of a bewildered imagination, than of scientific in- 
 duction. We can discover no such consequences as final ruin 
 to our system through its agency ; but even if such were dis- 
 covered, we may answer, that nature nowhere tells us that her 
 arrangements are eternal ; but rather, that decay is stamped 
 with the seal of the Almighty on every created thing. Change 
 may be one of the great laws of matter and motion, and yet 
 matter and motion be indestructible. The earth was called into 
 existence for a specific object, and when that object is accom- 
 plished, we are assured that another change awaits her. But 
 when earth, and sun, and planets, are again redissolved into 
 their primitive state, their atoms will still float on the ever- 
 rolling billows of the great ethereal ocean, to be again cast up, 
 on the shore of time, whenever it pleaseth Him to say, "Let 
 there be light." 
 
 * Prof. Pierce's Address, 1853. 
 
APPENDIX. 
 
 SINCE the author's arrival in New York for the purpose of 
 publishing his outlines, the third and fourth volume of the 
 Cosmos has been placed in his hands, containing the latest 
 uranological discoveries and speculations. It is now more than 
 twenty years since he began to investigate the subject he has 
 treated of, and fifteen since he first announced to the world, that 
 he had satisfactory evidence of his theory being true. Luckily, 
 perhaps, he has been cut off from the great streams of knowl- 
 edge ; and he may confess that it was with pardonable feelings 
 of gratification that he discovered in 1853, by the acquisition 
 of the two first volumes of the Cosmos, that the philosophic 
 mind of Humboldt had also pondered deeply on the planetary 
 peculiarities of size, density, distance, inclination of axes and 
 eccentricities of orbits, without eliciting any satisfactory rela- 
 tions. 
 
 From the tenor of the third and fourth volume of this learned 
 summary of scientific knowledge, it is evident that the question 
 of a medium filling space is more and more occupying the 
 learned world ; but the author is unable to discover any con- 
 sistent theory respecting it. The increasing interest attaching 
 to it, however, is evidently preparing the world for some radical 
 change in preconceived views. The explanation given by this 
 present theory to many prominent phenomena, is so totally con- 
 trary to that of the learned world, as to leave it untouched by 
 anything yet advanced. What the fifth volume of the Cosmos 
 
APPENDIX. 245 
 
 will contain, is not yet known in this country, neither has the 
 author been favored with any glimpse of the progress of sci- 
 ence as developed before the British Association ; he supposes, 
 however, that he yet stands alone in the position he has defined. 
 
 As a question of practical importance, the reader will find in 
 the work cited, the various opinions of the temperature of space. 
 Both Fourier and Poisson regard this as the result of radiated 
 heat from the sun and all the stars, minus the quantity lost by 
 absorption in traversing the regions of space filled with ether.* 
 But why should we regard the stars as the source of all mo- 
 tions ? Why cannot physicists admit the idea of an infinite 
 space filled (if we may use the expression) with an infinite me- 
 dium, possessing an unchangeable mean temperature long before 
 the formation of a single star. A star equal to our sun at the 
 distance of Sirius, would give about one million of million 
 times less heat than our present sun, which is only able to give 
 an average temperature to the whole globe about twenty de- 
 grees above freezing then let us remember that there are only 
 about fifty stars of the first and second magnitude, which give 
 more light (and by analogy heat also) than all the rest of the 
 stars visible. Such labored theories as this of Poisson's is a 
 lamentable instance of the aberrations of human wisdom. 
 
 We would also call the reader's attention to a late conclusion 
 of Professor Dove, viz. : That differences of temperature in dif- 
 ferent longitudes frequently exist on the same parallel of lati- 
 tude, or, in other words, are laterally disposed. This may be 
 thought adverse to the theory, but it should be borne in mind 
 that the annual mean temperature of the whole parallel of lati- 
 tude should be taken when comparing the temperatures of dif- 
 ferent years. 
 
 Another fact cited in the Cosmos apparently adverse to the 
 theory, is the idea entertained by Sir John Herschel, that the 
 
 * See Cosmos, p. 41, vol. 111. 
 
246 APPENDIX. 
 
 full-moon dissipates the clouds. This question has been fully 
 examined by Professor Loomis before the American Association, 
 and he concludes that there is not the slightest foundation for 
 the assertion taking as data the Greenwich observations them- 
 selves. 
 
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 duction of such new words and definitions as the progressive changes in the language 
 have rendered necessary ; and for this purpose the best and most recent authorities 
 have been anxiously consulted. It is, therefore, confidently anticipated that the voluxn* 
 will pr >ve not only a useful auxiliary to the student, but also a convenient Pocket (Jojp 
 Dftniou to the traveller wherever thd French langut.^e fs spoken." Prt/uci. 
 SO 
 
D. Appleton & CoSs Educational Publications. 
 PROP. G-. J. ABLER. 
 
 A Dictionary of the German and English Lan- 
 guages ; indicating the Accentuation of every German Word, contain 
 ing several Hundred German Synonyms, together with a Classification 
 and Alphabetical List of the Irregular Verbs, and a Dictionary of Ger- 
 man Abbreviations. Compiled from the Works of HILPERT, FLUOEL 
 GBEIB, HEYSE, and others. In two Parts: I. German and English II, 
 English and German. One large vol. 8vo., of over 1400 pages. Price $5 
 
 * In preparing this volume, our principal aim was to offer to the American student 
 of the German a work which would embody all the valuable results of the most recenl 
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 " In comparing the different German-English Dictionaries, it was found that nil of 
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 deavored to supply the desired words required in Chemistry, Mineralogy, Practical Art, 
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 valuable addition to the volume, are the synonymes, which we have generally given in 
 >n abridged and not unfrequently in a new form, from Hilpert, who was the first that 
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 complete in the German-English part, it was evidently our vocation to reverse the ordei 
 for this side of the Atlantic, and to give the utmost possible completeness and perfection 
 to the German part This was the proper sphere of our labor." Extract from 
 Preface. 
 
 PROF. G-. J. ABLER. 
 
 A Dictionary of the German and English Lan- 
 guage? Abridged from the Author's larger Work, for the use of 
 Learners, In two Parts : I. German and English II. English and ocr- 
 man One vol. 12mo., of over 800 pages. $1 75. 
 
 1 The larger work of Adler, of which this is an abridgment, has become an authority 
 on the German language. It is now well known and in extensive use among German 
 scholars. In making this abridgment, the author has gone over the entire ground of 
 the larger work again ; revising, condensing, or adding, as the case might require. AT 
 piovincialism, synonymes, and strictly scientific terms, have been excluded from these 
 pages, and every thing that might prove unnecessary, or embarrassing to beginners, or 
 to travellers and others, for wtom a smaller volume is better adapted. Some othci 
 c anges have also been made, which were deemed important to render the work st:)l 
 Tire acceptable for educational purposes. It can hardly fail to become as universally 
 ? .proved in the sphere for which it is designed, as the larger work has been by mow 
 M'' /anced German scholars." Courier & Eiviuirer. 
 
 "Professor Adler, who fills the department of the German Language and Literature 
 In the University of this city, is an accomplished scholar, and has done vast service tc 
 the cause of spreading a knowledge of the Teutonic language in this com ty. His largei 
 woik, of which this is an abridgment, is the very best extant for ad voiced students. 
 The work before us is abridged and simplified in several respects, to adapt It *c the 
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 27 
 
I). Apphton & CoSs Educational Publications. 
 SEOANE'S NEUMAN AND BARETTL BY VELAZQUEZ. 
 
 A Pronouncing Dictionary of the Spanish and 
 
 English Languages composed from the Spanish Dictionaries of the 
 Spanish Academy, Terreros, and Salva, upon the basis of Seoane'* 
 Edition of Neuman and Baretti, and from the English Dictionaries ol 
 Webster, Worcester, and Walker ; with the addition of more than 
 Eight Thousand New Words, Idioms, and Familiar Phrases, the Irreg- 
 ularities of all the Verbs, and a Grammatical Synopsis 01* both Langua 
 ges. By MARIANO VELAZQUEZ DE LA CADENA, Professor of the Spanish 
 Language and Literature in Columbia College, N. Y., &c., &c. In Two 
 Parts I. Spanish English. II. English Spanish. One volume imp. 
 8vo., of about 1400 pages. Strongly and neatly bound, price $5. 
 
 The great desideratum of an accurate, comprehensive, and well-digested Dictionary 
 of the Spanish and English languages is now first realized in this work by Professor 
 Velazquez. The value of Neuman and Baretti's Dictionary was greatly enhanced in the 
 edition by Dr. Seoane ; but it needed still greater improvements than Seoane has given 
 it, and the lapse of twenty years has made its deficiencies painfully apparent Professor 
 Velazquez has availed himself of all the valuable material accumulated by his predeces- 
 sors, lie has also enriched his pages from the latest edition of the Dictionary of the 
 Academy published subsequently to Seoane's revision and from the great work of 
 Cabrera, Terreros, and the indefatigable Salva. Many familiar words not found in the 
 Dictionaries, but constantly in use in Cuba, in Mexico, and in South America, are now 
 first given, as well as a long catalogue of mercantile terms, collected from reliable sources. 
 To these Professor Velazquez has added the many words and phrases, the much-needed 
 corrections, and the thorough revision suggested by his long experience as a teacher of 
 his mother tongue. Besides these improvements in the Vocabulary, the work is now 
 made a Pronouncing Dictionary. The pronunciation of every Spanish word is given in 
 a manner which will enable an English scholar to pronounce them at sight The method 
 of pronouncing English words in this Dictionary merits the particular attention of every 
 one whose mother tongue is the Castilian. It is based upon the method so much ad 
 mired and recommended by the learned Don Lorenzo Ileryas, in his " CatMogo de lot 
 Lenguas :" namely, by giving to every elementary sound in the language a correspond 
 Ing alphabetical character, and by restricting each of these characters to one singl* 
 Bound. By the help of this method, so superior to notation with figured vowels, no per. 
 eon willing to devote half an hour to the dozen new alphabetic characters need be at i 
 loss to pronounce correctly every English word in the Dictionary. The new and im- 
 proved orthography sanctioned by the latest edition of the Dictionary of the Academy 
 now universally adopted by the press is here given for the first time in a Spanish and 
 English Dictionary. Another new and most useful feature of the work is an " Outline 
 Grammar of the Spanish Language," and a "Grammatical Synopsis of the English Lan- 
 guage," cacli containing a grammar in miniature, and all the irregular verbs of both 
 languages. The volume is thus rendered complete, and made to answer all the parpoeea 
 f a grammar and a Dictionary. 
 
 Nearly ready, in one volume 12mo., 
 AN ABRIDGMENT OF THE ABOVE. 
 
 Tliis Abridgment is a miniature copy of the great octavo work by Pr<wfessor Vela* 
 
 Suez, and contains all its most important additions and improvements. Expurgated of 
 ie antiquated orthography, and the manifold errors and absurdities so common in 
 Spanish and English Abridgments, it Is intended as a reliable work of reference for 
 business men, and for all the ordinary uses of a Dictionary. The scholar who wishes to 
 become well acquainted with the Spanish and English classics, will hardly be satisfied 
 with any thing less than the octavo edition ; but as a pocket companion for beginners, 
 for travellers, or for the use of those who consult a dictionary for practical purposes, thl 
 abridgment will be found superior to any other work yet published, 
 
 91 
 
D. AppUton & Co." 1 * Educational Publication*. 
 
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 13 
 
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