nundred years) in which the polar and equatorial diameters of this planet can be measured, and their difference, if any, ascertained, so as to determine whether its figure, like that of the earth and several other planets, be spheroidal. But as this planet may not happen for a series of years to be in the precise position for such an observation, the attempt to determine the points now stated, even when the planet happens to be placed in the requisite circumstances, would, in all probability, fail, if a number of observers at the same time, in different places, were not engaged in the observation; on account of the uncertainty of enjoying a serene sky at one particular place, during the moments when the observation behooved to be made. Whereas, by a multitude of observations in different places, the object in view could not fail of being determined. The disputes respecting the period of rotation of this planet (whether it be 23 hours 20 minutes, or 24 days 8 hours) might also be settled, were a number of persons to observe its surface with equatorial telescopes in the daytime; particularly in those southern climes where the air is serene, and the sky exhibits a deep azure, where, in all probability, spots would be discovered, which could be traced in their motions for successive periods of twelve hours or more, which would determine to a certainty the point in question. The following figure and explanation will perhaps tend to show the reason of the dispute which has arisen in reference to this point. Let A represent a spot on the surface of Venus. A... As this planet is seen, by the naked eye, only in the morning a little before sun-rise, or in the evening a short time after sun-set-the motion of the spot cannot be traced above an hour or two in succession; and, consequently, during that time, its progressive motion is almost imperceptible. Suppose the observation to have been made in the evening, after sun-set, the next observation cannot be made till about the same time, on the following evening, when it is found that the spot has moved from A to B. But it is still uncertain whether the spot has only moved from A to B, since the last observation, or has finished a complete revolution, and moved the distance A B as part of another revolution round the axis of the planet. This point can only be ascertained by tracing the motion of the spot without interruption for 10, 12, or 14 hours, when, if the rotation is performed in 23 hours, the motion of the spot could be traced without interruption across the whole disk of the planet. But such an observation could only be made in the day-time, in a serene sky, and by means of equatorial instruments, aud by numbers of observers in different places, where the attention is directed to the same object. But the limits to which I am confined, in throwing out these cursory hints, prevent me from entering into minute details. In regard to comets, it is scarcely necessary to remark, that were the number of those whose attention is directed to a survey of the heavens considerably increased, many of those eccentric bodies, which pass and repass within the orbits of the planets without being perceived, could not fail of being detected. Were multitudes of such persons engaged in exploring the celestial regions, on opposite sides of the globe, those conets which pass within the limits of our view, and which are above our horizon only in the day-time, and consequently invisible, would be detected, during the night, by our antipodes in the opposite regions of the globe. By this means the number of those bodies belonging to our system, the diversified phenomena they present, the form of their trajectories, the periods of their revolutions, the nature of their tails, and their ultimate destination, might be more accurately determined. With respect to the fixed stars, particularly those termed variable stars, the results of a multitude of observations made by different persons, might lead us to determine, whether those changes in brightness which they undergo, arise from the transits of 'arge planets revolving around them, and thus furnish direct evidence of their being the centres of systems analogous to our own,-or whether they be occasioned by large spots which periodically interpose between our sight, and then disappear in the course of their rotation,-or whether the distance of such stars be changed by their revolving in a long narrow ellipse, whose transverse axis is situated nearly in our line of vision. In the several instances now stated, an immense variety of successive observations, by numerous observers at different stations, are requisite to accomplish the ends in view; but the limits of this section prevent me from entering into those details requisite for rendering the hints now suggested perspicuous to those who nave not devoted their attention to this sub- surface, were such minute observations as those ject. The Moon being the nearest celestial body to the earth, it might have been expected that the variety of scenery on her surface, and even some parts of her physical constitution, might have been ascertained and delineated. Yet all that has hitherto been discovered with certainty in relation to this body is, that her surface is strikingly diversified with mountains and valleys, with vast caverns or hollows surrounded with mountainous ridges, and with several elevated peaks, which rise, like a sugar loaf, from the middle of the plains. We have no accurate delineation of the lunar scenery, as exhibited in the various stages of the moon's increase and decrease, except those which have been published by Hevelius and Schroeter, which have never been translated into our language, and, consequently, are very little known. Most of our English books on astronomy contain nothing more than a paltry and inaccurate view of the full moon, which has been copied by one engraver from another, without any improvements, ever since the days of Ricciolus, and long before the telescope was brought to its present state of inprovement. It is not from a telescopic view of the full moon that any specific deductions can be made respecting the appearance and arrangement of her diversified scenery; but from long-continued observations of her surface about the period of the quadratures, and at the times when she assumes a crescent or a gibbous phase; for it is only at such times that the shadows of her cavities and mountain-ridges can be distinctly perceived. As there is none of the celestial bodies whose constitution and scenery we have so excellent an opportunity of inspecting, had we a sufficient number of astronomical observers, furnished with good telescopes, the surface of this globe might be almost as accurately delineated as that of the earth, and the most prominent changes that take place on its surface plainly detected. In order to bring to light the minute parts of its scenery, it would only be requisite to distribute the entire surface of this luminary among a hundred or a thousand observers, allotting to each one or more spots as the particular object of his attention, with the understanding, that he is to inspect them with care through every variety of shade they may exhibit, and during the different stages of the moon's increase and decrease, and delineate the different aspects they may present. When we consider that, by means of a telescope which magnifies 200 times, an object on the moon that measures only 600 yards may be perceived as a visible point, and by one which magnifies 800 times, an object not larger than 150 yards in diameter may be distinguished-we can scarcely entertain a doubt, that a number of interesting discoveries night soon be made on the lunar now suggested to be continued for a series of years, which might afford sensible and demonstrative evidence of the moon's being a habi table world. But before attention to such ob jects become general, and the number of astronomical observers be increased far beyond what it is at present, such discoveries can scarcely De expected. I shall only remark farther on this head, that several discoveries have been made by accidentally directing a telescope to certain parts of the heavens. It is well known that Miss Herschell, while amusing herself in looking at the heavens through Sir William Herschell's telescope, discovered at different times a variety of comets, which might otherwise have passed unnoticed by the astronomical world; and several of the new planets which have been discovered within the last 50 or 60 years, were detected when the discoverers were employed making observations with a different object in view. The splendid comet which appeared in our hemisphere in 1811, was first discovered in this country by a sawyer, who, with a reflecting telescope of his own construction, and from his sawpit as an observatory, descried that celestial visitant before it had been noticed by any other astronomer in North Britain. The author of this work detected this comet a day or two afterwards, before he had been informed of the discovery, while he was taking a random sweep over the northern region of the heavens. He had directed his telescope to a certain star in the neighbourhood of Ursa Major, and immediately afterwards, taking a general sweep upwards and downwards, and to the east and west, an uncommon object appeared in the field of view, which, after a little inspection, was perceived to be a comet, and he naturally concluded that he had made the first discovery, till the newspapers afterwards informed him that it had been detected a day or two before. It was while Sir W. Herschell was inspecting some small stars near the foot of Castor, with a different object in view, that he discovered the planet which bears his name, and which he at first took for a comet. It had been seen thirty years before, but for want of numerous observers to mark its motions, it had been marked in catalogues as a fixed star. It was while Mr. Harding of Lilienthal, near Bremen, was forming an atlas of the stars so far as the eighth magnitude, that, on the 1st September 1804, he discovered in the constellation Pisces the planet Juno, one of the four asteroids situated between the orbits of Mars and Jupiter. If, therefore, instead of a few individuals occasionally engaged in surveying celestial phe The name of this gentleman is Mr. Veitch, and I believe he resides in the neighbourhood of Kelso. nomena, and chiefly confined to a small portion of Europe, were thousands and ten thousands of telescopes daily directed to the sky from every region of the earth, and were distinct portions of the heavens allotted to distinct classes of observers, as the object of their more immediate research, every portion of that vast concave, with the numerous globes which roll within its wide circumference, as far as human vision assisted by art can penetrate, would ere long be thoroughly explored, and its hidden worlds disclosed to view. No comet could pass within the orbit of Jupiter without being detected,-the undiscovered planets belonging to our system, if any still remain, would be brought to view,the periodical changes on the surfaces and in the atmospheres of the planets already discovered, with all their diversified phenomena, would be more accurately ascertained and delineated, the path of the solar system in absolute space, the velocity of its motion, the distant centre about which it revolves, and the centre of gravity of the nebula to which it belongs, might be determined,-the changes and revolutions that are taking place among the fixed stars, the undiscovered strata of nebule, -the old systems that are going into decay, the new creations that may be emerging into existence, and many other sublime objects which at present lie concealed in the unexplored regions of space, might be brought within the range of human contemplation, and astronomy, the sublimest of all the sciences, approximate towards perfection. For making the observations now supposed, a profound knowledge of the physical and mathematical principles of astronomy is not absolutely necessary. All the qualifications essentially requisite are,-a general knowledge of the elements of the science, of the celestial pheno mena which have already been explored, and of the method of determining the right ascension and declination of any observed phenomenon,qualifications, which every person of common understanding can easily acquire. I might next have illustrated the general position laid down in the beginning of this section from the science of chymistry. This science, having for its object to ascertain the ingredients that enter into the composition of bodies, the nature of those ingredients, the manner in which they combine, and the properties resulting from their combination; or, in other words, an analytical examination of the material world, and the principles which concur to produce its diversified phenomena; it is apparent, at first view, that an immense number and variety of experiments are indispensably requisite for accomplishing such objects; and, consequently, that its progress towards perfection cannot be acceerated, unless multitudes of experimenters coneur in observing the phenomena of nature, and the processes of the arts, in instituting analy tical experiments, and in prosecuting every inquiry which has a tendency to promote its im provement. It is chiefly in consequence of the increased number of its cultivators that this science has risen to the distinguished rank it now holds among the useful departments of humau knowledge, and that so many brilliant discoveries have rewarded the investigations of its votaries. Wrenched from the grasp of empi rics and alchymists, and no longer confined to the paltry object of searching for the philosopher's stone, it extends its range over every object in the material world, and sheds its influence over all the other departments of physical science; and as its votaries increase in numbers and in perseverance, it will doubtless bring to light scenes and discoveries still more interesting and brilliant than those which have hitherto been disclosed. Illustrations of the same de scription might also have been taken from optics, electricity, magnetism, galvanism, pneumatics, and other departments of natural science; but having protracted this section to a disproportionate length, the instances already stated will, I presume, be sufficient to prove the truth of the position, "that a general diffusion of knowledge would have a powerful influence on the progress of science." From the few hints now given, and from many others that might have been suggested, had my limits permitted, it will appear, that much still remains to be accomplished ull any science, even those which are farthest advanced, arrive at perfection. The reason is obvious; the scene of universal nature has never yet been thoroughly surveyed, and never will be, till the eyes and the intellects of millions be fixed in the contemplation of its multifarious and diversified objects and relations. Till the universe, in all its aspects, so far as it lies within the range of human inspection, be more particularly explored, clouds and darkness will continue to rest or many interesting departments of knowledge, and many of our most specious theories in the sciences must be considered as reposing on slender and unstable foundations. Prior to the introduction of the inductive method of philosophizing, men of science were extremely prone to the framing of hypotheses, before they had atten tively surveyed and collected the requisite facts, and when only a few scattered fragments of nature were present to their view. Theory was reared upon theory, and system upon system; each of them obtained its admirers and its period of applause, but, in consequence of modern researches, they have now passed away like a dream or a vision of the night. The crystalline spheres with which Ptolemy had enclosed the heavens are now dashed to pieces; the vortices of Des Cartes have long since ceased thetr whirling; the terraqueous globe which Tychs had fixed in the centre of the universe is now set in rapid motion through the heavens, in company with the planetary orbs; and the abyss of water with which Burnet had filled the internal cavity of the earth is now converted into a mass denser than the solid rock. The Terra Austraus Incognito, which served as a prop to certain theories, has completely evanished, and is now transformed into a dreary mass of water and ice. The subtile ether, which formerly accounted for so many phenomena, is now evaporated into electricity and heat. Whiston's idea of the cometary origin of our globe, and Buffon's fancy of the earth's being a splinter struck from the body of the sun, are fast sinking into oblivion; and such will be the fate of every theory, however specious, which is not founded on the broad basis of inductive evidence. departments of the same science marked out for distinct classes of individuals, as the more immediate field of their investigation, on the principle of the division of labour, every leading principle and fact in relation to that science would soon be detected and illustrated in all its practical bearings. Even as matters presently stand, were the whole literary and scientific world to form itself into one great republic, and to allot the several branches of every department of knowledge to the different classes of such a community, according to their respective tastes and pursuits, as the object of their more particular attention, it might be followed by many interesting results, and important discoveries and improvements. But we live in too early a period in the history of science to expect a general interest to be taken in such objects; Even in the present day, there is still too we are but just emerging from the gloom of iggreat a propensity to generalize, without sub norance and superstition; the great body of mitting to the trouble of observing phenomena, mankind still suffer their faculties to lie in a and noting their various modifications and at- state of languor and inactivity, and those who tendant circumstances. The human mind is are more vigorous and alert are too much enimpatient, and attempts to reach the goal by the grossed in commercial speculations, in grasping shortest and most rapid course, while observa- at power and opulence, and in the indulgence tion and experiment are tedious and slow. In- of sensual gratifications, to think of attending stead of surveying the material world with his to the interests of science and the progress of own eyes, and investigating, by observation and the human mind. Much, however, might be experiment, its principles and laws, the man of accomplished in this respect, with ease and genius frequently shuts himself up in his closet, pleasure, by various classes of society, and and from a few scattered fragments of nature, without interfering with their ordinary avocaconstructs, in his imagination, a splendid theory, tions, were their minds inclined and their atwhich makes a noise and a blaze for a little, tention directed to such pursuits. Sailors, in like an unsubstantial meteor, and then evanishes crossing the Atlantic, the Pacific, and the Ininto air. The system of nature, though di- dian oceans, have frequently excellent opporturected in its general movements by a few simple nities of observing the phenomena of the waters, laws, is too grand and extensive, and too com- the atmosphere, and the heavens, peculiar to plex in many of its parts, to be grasped by a the climates through which they pass; and were few individuals, after a cursory survey; and, the facts presented to their view observed with therefore, to attempt to comprehend its multi- care, classified, and recorded, they might, in farious revolutions, phenomena and objects many instances, contribute to the advancement within the range of theories founded on a par- of science. But thousands of such persons tial view of some of its detached parts, is not can sail twice "from Indus to the frozen pole, only an evidence of presumption and folly, but as ignorant as their log, and as stubborn as their tends to damp our ardour in prosecuting the only compass," without importing one intellectual sure path which leads to discovery, and to frus- acquisition. The observations made during a trate what appears to be one of the designs of single voyage across the Atlantic, by a single the Creator, namely, to grant to the intelligent observer, M. Humboldt, on the aspect of the inhabitants of our globe a gradual display of his Antarctic region of the heavens-the peculiar stupendous plans in the universe as the reward of azure of the African sky-the luminous meteors their incessant and unwearied contemplation of his of the atmosphere-the tides, the currents, and wondrous works. the different colours of the oce", and other phenomena which happened to present themselves to his view-are of more value to the scientific world than the observations of ten thousands of other beings who, for a series of years, have traversed the same regions. Yet these possessed, on an average, the same sentient organs, the same intellectual powers, though somewhat differently modified and di rected, the same natural capacities for observa tion as this distinguished philosopher, which re Were the period arrived (and of its arrival I entertain no doubt, from the present movements of the human mind) when the majority of mankind shall devote a portion of their time and attention to the purposes of science, and to the con emplation of nature-then the different rastes of individuals, and the various situations in which they may be placed, would lead them to cultivate more particularly the science most congenial to 'heir minds; and were distinct quired only an impulse to be given in a certain direction, in order to accomplish the same ends. And was Humboldt more burdened and perplexed, or did he feel less comfortable and happy than his ignorant and grovelling associates in the ship that wafted them across the ocean? No. He felt emotions of delight and intellectual enjoyments to which they were utter strangers. While they were lolling on their hammocks, or loitering upon deck, viewing every object with a "brute unconscious gaze,' and finding no enjoyment but in a glass of grog, -a train of interesting reflections, having a relation to the past, the present, and the future, passed through the mind of this philosopher. He felt those exquisite emotions which arise from perception of the beautiful and the sublime; he looked forward to the advancement of natural science as the result of his observations, and beheld a display of the wisdom and grandeur of the Almighty in the diversified scenes through which he passed. Such observations and mental employments as those to which I allude, so far from distracting the mind, and unfitting it for the performance of official duties, would tend to prevent that languor and ennui which result from mental inactivity, and would afford a source of intellectual enjoyment amidst the uniformity of scene, which is frequently presented in the midst of the ocean. From the whole that has been now stated on this subject, it appears, that in order to make science advance with accelerated steps, and to multiply the sources of mental enjoyment, we have only to set the machinery of the human mind (at present in a quiescent state) in motion, and to direct its movements to those objects which are congenial to its native dignity and its high destination. The capacity of the bulk of mankind for learning mechanical employments, and for contriving and executing plans of human destruction, proves that they are competent to make all the researches requisite for the improvement of science. The same mental energies now exerted in mechanical labour and in the arts of mischief, if properly directed, and acting in unison, and accompanied with a spirit of perseverance, wouid accomplish many grand and beneficent effects, in relation both to the physical and moral world, and would amply compensate the occasional want of extraordinary degrees of mental vigour. Were only a hundred millions of eyes and of intellects, (or the tenth part of the population of our globe) occasionally fixed on all the diversified aspects, motions and relations of universal nature, it could not fail of being followed by the most noble and interesting results, not only in relation to science, but to social and moral order, and to the general melioration of mankind. Were this supposition realized, our travellers, merchants, and mariners, along with the pro duce of foreign lands, might regularly import, without the least injury to their commercial interests, interesting facts, both physical and moral, scientific observations, chymical experiments, and various other fragments of useful information for rearing the Temple of Science, and extending the boundaries of human knowledge. SECTION IV. ON 1E PLEASURES AND ENJOYMENTS CONNECTED WITH THE PURSUITS OF SCIENCE. MAN is a compound being; his nature con sists of two essential parts, body and mine Each of these parts of the human constitutio.. has its peculiar uses, and is susceptible of pe culiar gratifications. The body is furnished with external senses, which are both the sources of pleasure and the inlets of knowledge, and the Creator has furnished the universe with objects fitted for their exercise and gratification. While these pleasures are directed by the dictates of reason, and confined within the limits prescribed by the Divine law, they are so far from being unlawful, that in the enjoyment of them we fulfil one of the purposes for which our Creator brought us into existence. But the pursuit of sensitive pleasures is not the ultimate end of our being; we enjoy such gratifications in common with the inferior animals; and in so far as we rest in them as our chief good, we pour contempt on our intellectual nature, and degrade ourselves nearly to the level of the beasts that perish. Man is endowed with intellectual powers, as well as with organs of sensation, with faculties of a higher order, and which admit of more varied and sublime gratifications than those which the senses can produce. By these faculties we are chiefly distinguished from the lower orders of animated existence; in the proper exercise and direction of them, we experience the highest and most refined enjoyments of which our nature is susceptible, and are gradually prepared for the employments of that immortal existence to which we are destined. The corporeal senses were bestowed chiefly in subserviency to the powers of intellect, and to supply materials for thought and contemplation; and the pleasures peculiar to our intellectual nature, rise as high above mere sensitive enjoyments, as the rank of man stands in the scale of existence, above that of the fowls of the air, or the beasts of the forest. Such pleasures are pure and refined; they are congenial to the character of a rational being; they are more permanent than mere sensitive enjoyments they can be enjoyed when worlday comforts are |