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gradually improving his mental powers, and must, from this very circumstance, be better ualified thun others for exercising them in his particular trade or profession. For the habit of exerting the intellectual faculties in any one department, must necessarily fit them for vigorous exertion on any other object, whether mechanical, agricultural, social, or domestic, to which the attention may be directed. The evils which at present derange the harmony of society, so far from arising from a vigorous exertion of intellect, are to be ascribed, for the most part, to an opposite cause. The intellectual powers, in the case of the great bulk of mankind, lie in a great measure dormant, their energies are not sufficiently exerted in any department of active life; and when occasionally roused from their inactivity, they are too frequently exercised in the arts of deception, of mischief, and of human destruction. To direct the current of human thought, therefore, into a different channel, besides its influence on the progress of science, would be productive of many happy effects on the social and moral condition of mankind; and, as far as my experience goes, with a very few exceptions, I have found, that those who are addicted to rational pursuits are the most industrious and respectable hembers of civil and Christian society.

The above hints have been thrown out with the intention of showing, that, as all science is ‘ounded on facts, and as every person possessed of the cornmon organization of human nature is capable of observing facts, and of comparing them with one another, as the discovery of new truths is owing more to the concentration of the mental faculties on particular objects, and to several accidental circumstances, than to the exertion of extraordinary powers of intellect, and as the sciences have generally improved in proportion to the number of those who have devoted themselves to their cultivation,-so there is every reason to conclude, that the diffusion of general knowledge and of scientific taste, and consequently, the increase of scientific observers, would ensure the rapid advancement of the different sciences, by an increase of the facts in relation to them which would thus be discovered.

I shall now endeavour to illustrate the positions stated above, by a few examples in relation to two or three of the physical sciences.

Geology.—This science is yet in its infancy; and some of i's first principles require to be confirmed and illustrated by an induction of an immense number of facts of various descriptions. It is a branch of knowledge altogether founded upon facts palpable to the eye of every common observer. Its object is, to investigate the internal structure of the earth.-the arrangement of its component parts, the changes which its

materials have undergone since is original forma.ion,--an the causes which have operated in the production of these changes. To determine such objects, it is requisite that an immease variety of observations be made on the form, position, and arrang inent of mountains, —on the beds of rivers, the interior of caverns,—the recesses of ravines.-the subterraneous apartinents of mines, the fissures and chasms which abound in Alpine districts, and even on the bottom of the ocean, in so far as it can be explored; and that a multitude of facts be collected in relation to the materials and position, the elevation and in:lexion, the fraction and dislocation of the earth's strata—calcareous petrifactions--metallic veins—decomposed rocks - mosses — rivers — lakes—sand-banks—seacoasts—the products of volcanoes—the composition of stone, sand, and gravel—the organic remains of animal and vegetable matter, in short, that the whole surface of the terraqueous globe, and its interior recesses, be contemplated in every variety of aspect presented to the view of man. The observations hitherto made in reference to such multifarious objects have been chiefly confined to a few regions of the earth, and the facts which have been ascertained with any degree of precision, have been collected, chiefly by a few individuals, within the last fifty or sixty years. From such partial and limited researches, general principles have been deduced, and theories of the earth have been framed, which could only be warranted by a thorough examination of every region of the globe. Hence one theory of the earth has successively supplanted another for more than a century past. The theories of Burnet, Whiston, Woodward, Buffon, and Whitehurst, have each had its day and its admirers, but all of them are now fast sinking into oblivion, and in the next age will be viewed only as so many philosophical rhapsodies, and ingenious fictions of the imagination, which have no solid foundation in the actual structure of the earth. Even the foundations of the Huttonian and Wernerian systems, which have chiefly occupied the attention of geologists during the last thirty years, are now beginning to be shaken, and new systems are constructing composed of the fragments of both. One principal reason of this diversity of opinion respecting the true theory of the earth, undoubtedly is, that all the facts in relation to the external and internal structure of our globe have never yet been thoroughly explored. Instead of retiring to the closet, and attempting to patch up a theory with scattered and disjointed fragments, our province, in the mean time, is, to stand in the attitude of surveyors and observers, to contemplate every aspect which terrestrial nature presents, to collect the minutest facts which relate to the object in view, and then leave to succeeding generatious

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the task of constructing a theory from the materials we thus prepare.

Were we now to suppose, that, instead of one observer of geological facts that now exists, thousands were distributed throughout the dis. ferent continents and islands, having their minds occasionally directed to such investigations; that the miners and labourers in coal-pits, ironmines, and quarries, not only in Europe, but throughout Mexico and Peru, in the East and West Indies, in Canada, in New Holland, in Southern Africa, in the ranges of the Alps, the Andes, the Himalayas, and other quarters, observed with attention the various phenomena of nature subject to their inspection, with this obiect in view: that sailors, missionaries, and travellers of every description, contemplated the different aspects of nature in the regions through which they passed, and recorded the facts which came under their observation, for a similar purpose; and could we still farther suppose, that the great body of mankind in every clime might, at no distant period, have their minds directed to similar subjects, there cannot be the least doubt but an immense multitude of important facts would soon be accumulated, which would throw a striking light on the constitution of our planetary globe, and on the changes and revolutions through which it has passed, which would form a broad basis for the erection of a true theory of the earth, and tend either to establish or to overthrow the hypotheses which have hitherto been framed. Persons in the lower spheres of life have, in many cases, more frequent opportunities of ascertaining facts of the description to which I allude, than many others who are placed in an elevated rank. Colliers, quarriers, miners of every description, and the inhabitants of Alpine districts, are almost daily in contact with objects connected with geological research; and it is only requisite that their attention be directed to such inquiries—that the knowledge of a few elementary terms and principles be imparted to them—that they be directed to classify the facts which fall under their observation—and that a systematic list of queries, such as those published some years ago by the London “Geological Society,” be put into

their hands. *

• The queries to which I refer may be seen in the “Monthly Magazine” for June 1817, pp. 436–9. A few years ago, some interesting fossil remains, supposed to be the teeth and other bones of the extinct animal designated by the name of Mammoth, were almost entirely destroyed through the ignorance of some labourers in the parish of Horley, who happened to hit upon them when digging gr . After cleaving them to pieces with their pick-axes, and finding it added nothing to their store of knowledge, “they threw away the fragments among the heafs of gravel, and the subject was consigned to obliwion ; and it was only by accident that two entire teeth were found by a gentleman in the neighbourhood. The bones supposed to have been either destroyed or lost, are a very large bone, supposed to

Natural History.—It is evident that the extension and improvement of this department of knowledge depends almost entirely on obse: ation. Although a considerable accession has of late years been made to our knowledge in this branch of study, yet much still remains to be accomplished before all the objects it em!, aces be thoroughly explored. Our acquaintance with the zoology, botany, and mineralogy of New Holland, Polynesia, Birmah, China, Tartary, Thibet, Africa, and America, is extremely limited; and even within the limits of Europe, numerous unexplored regions still lie open to the future researches of the natural historian. So numerous are the objects and investigations which natural history presents, that although its cultivators were increased ten thousand-sold, they would find sufficient employment in the prosecution of new discoveries for many centuries to come. Even those minute objects, in the animal and vegetable kingdoms, which lie beyond the natural sphere of human vision, and which the microscope alone can discover, would afford scope for the investigations of thousands of ingenious inquirers, during an indefinite series of ages. And it ought never to be forgotten, that every new object and process we are enabled to trace in this boundless field of observation, presents to us the Deity in a new aspect, and enables us to form more enlarged conceptions of that power and intelligence which produced the immense assemblage of beings with which we are surrounded.

Independently of the additions that might be made to our knowledge of animals, vegetables and minerals, there are several facts in natural history which might be more precisely ascertained and explained, were common labourers and others in the same rank of life inspired with the spirit of philosophical observation. For the illustration of this, I shall state only one particular circumstance. It is a fact, which, however inexplicable, must be admitted, that toads have been found alive in the heart of solid rocks, and in the trunks of trees, where, they have been supposed to have existed for ages without any apparent access to nourishment or to air. Such facts are supported by so numerous and so respectable authorities, that it would be vain to call in question their reality; and they assume a more mysterious aspect, from the circumstance, that toads, when placed in the exhausted receiver of an air-pump, like all other animals, soon lose their existence. That the

have been a thigh bone: a huge blade bone; and a tusk of ivory, perfect in its form, described as being about half a rod in length.” Had these labourers been aware of the interesting nature of such fossils, they might have been all preserved entire; and this circumstance shows how important such occur

rences, and the observations and researches of com

mon labourers, might sometimes prove to the geolo. gist and the general student of nature.

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tead is not the only animal which has been found in similar instances, appears from a notice in the Monthly Magazine for April 1817, which states, that “a large lizard or serpent was found by so me miners, imbed led in a stratum of mireral substance, and lived for some time after it was extricated.” As the mineral substance in which this animal was found was at the bottom of a deep mine, and connected with the surround1ng strata, we are almost under the necessity of concluding, that it must have existed in that state for many years. Now, it is proper to take into consileration, that such facts have been discovered, in the first instance, by labourers, quarriers, miners, and others engaged in laborious cecupations, who, with the limited knowledge they presently possess, are unqualified for attending to all the circumstances which require to be noticed in conducting philosophical researches. Were persons of this description accustoned to examine every uncommon occurrence of this kind with a philosophic eye ; were they, in such cases as those to which I have now referred, to examine, with accuracy, whether chinks or fissures, either horizontal or perpendic lar, existed in the rocks, or were connected with the holes or vacuities of the old trees, where toads were found alive; and were every other circumstance, which a scientific investigator would take into accoun', accurately observed and recorded, such observations might ultimately lead to some rational explanations of such unaccountable facts. At any rate, as those who belong to that class of society to which I allude, have many opportunties of contemplating the various objects and operations of the material world, their accumulated observations, when scientifically directed, could not fail of enlarging our knowledge of facts in several departments of the history of nature. Meteorology.—In this department of physical science, numerous facts still remain to be ascertained, before we can attempt to explain the causes of various interesting phenomena. We have hitherto been unable to collect with precision all the facts in relation to the diversified phenomena of the atmosphere, and are still at a loss to explain, on known principles, the causes which operate in producing many atmospherical appearances. We are still in a great measure ignorant of the aurora borealis, with respect to its nature and origin, its distance from the surface of the earth, what precise connexion it has with the magnetic and electric fluids, and why it has been frequently seen at some periods, and been invisible at others. We are in a similar state of ignorance in regard to luminous and fiery meteors, as to their different species and varieties, the velocity and direction of their motions, their intuence on other atmospherical phenomena, on vegetation, and on the weather, and the principles in nature which operate in their

production. Although the general cause of thunder-storms is in some measure ascertained, yet we are ignorant of the causes of a variety of phenomena with which they are sometimes accompanied, and of some of the chymical agents by which they are produced. To determine the origin of meteoric stones, the particular regions in which they are produced, the causes of their extreme velocity, the oblique direction of their motion, and the agen's which concur in their formation, has hitherto baffled the researches of the whole philosophical world. Even the nature of the clouds, their various modifications, their different electric states, the causes which combine to produce their precipitation into rain, the nature of evaporation, together with an immense. number of facts requisite for laying the foundation of a correct theory of the weather, are still hid in obscurity. It is obvious, that a thorough knowledge of atmospherical phenomena cannot be acquired, before we have ascertained not only the particular facts and appearances connected with the atmosphere, but all the preceding, concomitant, and consequent circumstänces with which they are generally accompanied ; and to determine such particulars requires an immense variety of observations, both by day and by night, through all the regions of the earth. Before such facts be more fully ascertained, our attempts to account for various atmospherical phenomena must prove unsatisfactory and abortive. Hence, the causes assigned by philosophers of the last century for the production of rain, hail, dew, fireballs, and other meteors, are now considered nugatory and erroneous; and few will be bold enough to maintain that we have yet arrived at the knowledge of the true causes. If these sentiments be admitted, it will follow, that an increased number of observers of the scenery of the atmosphere, in different climates, with a scientific object in view, could not fail of increasing our knowledge both of the phenomena which take place in the regions of the atmosphere, and of the powers of nature which operate in their production With respect to the aurora, boreales, some data might be ascertained for determining their height above the surface of the earth, which might lead to a discovery of their true cause, were a multitude of observers, in different places, at the same moment, to take the altitude and bearing of any particular coruscation, particularly of the modification of this phenomenon which assumes the form of a rainbow or luminous arch, which can instantly be done by noting the series of stars which appear about the middle or sides of the arc at any particular instant. By this means the parallactic angle might be found, and the distances of the places of observation, or their difference of latitude, if directly north and south of each other, would form base hues for determining the perpendicular elevation of the phenomenon. In reference to luminous meteors, as they are most frequently seen in the night-time, men of science and persons of elevated rank have seldom opportunities of observing their diversified phenomena, and the circumstances with which they are preceded and accompanied. But while persons of this class are reclining on beds of down, or regaling themselves at the festive board, hemmed in from the view of the surrounding sky by the walls and curtains of their splendid apartments, many in Athe lower walks of life are “keeping watch by night,” or travelling from place to place, who have thus an opportunity of observing every variety of atmospherical phenomena; and it is not unlikely may have seen several species of luminous and fiery meteors unknown to the scientific world. Were persons of this description, particularly watchmen, soldiers, sailors, mail-coach guards, policemen, and such like, capable of observing such appearances with scientific interest and accuracy, and of recording their observations, various important additions might be made to the facts which compose the natural history of the atmosphere. Similar additions might be made to our knowledge of thunder-storms, were their phenomena and concomitant circumstances accurately noted by a vast number of persons in different places. It might, for example, be determined, from a multitude of observations made with this special object in view, at what distance from the earth a thunder-cloud may explode without danger? —in what circumstances, and at what elevation it generally attains its striking distance, and brings us within the range of its destructive influence 2—what particular effects, hitherto unobserved, are produced by lightning on animal, vegetable, and mineral substances —to what practical purposes its agency might be applied, —and how its destructive ravages might be averted or diminished 2 The same remarks will apply to the singular phenomenon of meteoric stones. These have seldom been observed at the instant of their descent by men addicted to philosophical research ; but chiefly by peasants, labourers, and mechanics, who, at present, are generally unqualified for attending to every circumstance in the preceding and concomitant phenomena connected with their descent, with the discerning eye of a philosopher; and therefore, we may still be ignorant of certain important facts in the history of the fall of these bodies, which may long prevent us from forming any rational theory to explain their causes, or to determine the regions whence their origin is derived. Astronomy.—My next illustration shall be taken from the science of astronomy. Though this is among the oldest of the sciences, and its general principles are established with greater

precision than those of almost any other department of science, yet many desiderata requisite to its perfection, still remain to be ascertained. The late discovery of several new planets, both primary and secondary, leads us to conclude, that other globes of a similar nature, belonging to our system, may still lie hid in the distant spaces of the firmament. The spheroidal figure of some of the planets—their periods of rotation—the nature of the changes which appear to take place on their surfaces or in their atmospheres—the precise nature of the solar spots, the causes of their changes, and the influence which those changes produce on our earth or atmosphere—the parallax of the fixed stars—the rate of motion of the planetary system in absolute space—the gradual formation of nebularthe nature of variable stars—the number of comets, their periods, the nature of their tails and atmospheres, and their uses in the system of nature—with many other interesting particulars of a similar description, still remain to be ascertained. To determine such objects, requires a multiplicity of long-continued observations in every region of the heavens; and it must be evident, that the more we increase the number of astronomical observers, the greater chance we shall have of acquiring a more accurate and comprehensive knowledge of the bodies which roll in the distant regions of the universe, and of the relations they bear to one another, and to the whole system of nature. This position might be illustrated by a few examples. The surface of Jupiter has been found to be diversified with a variety of spots and belts: the belts, which are considerably darker than the general surface of the planet, are observed to vary in their number, distance, and position. Sometimes only one or two, and sometimes seven or eight belts have been observed; sometimes they are quite distinct, and at other times they seem to run into each other; and, in some instances, the whole surface of this planet has appeared to be covered with small curved belts that were not continuous across his disk. The following figures represent some of the diversified views which Jupiter sometimes exhibits. Fig. 1, is copied from Dr. Long, and appears to be one of the views of this planet taken by the celebrated Cassini. It consists of about nine different belts. Fig. 2, is copied from Schroeter, and exhibits a view of Jupiter about the time of its occultation by the moon, on the 7th of April 1792. Fig. 3, is one of Sir W. Herschel's views of this planet, as it appeared on the 28th May 1780, when the whole disk of Jupiter appeared covered with small curved belts, or rather lines, that were not continuous across his disk. Fig. 4, contains a view which is nearly the appearance which Junior exhibits at present, and which is not much different from his appearance for several years past. These appearances may be seen by a good achromatic telescope, magnifying from 80 to 150 times. These views demonstrate, that changes of considerable magnitude are occasionally taking place, either on the surface or in the atmosphere of this planet, which it would be of some importance to ascertain, in order to our acquiring a more intimate knowledge of the physical constitution of this globe. Now, were a number of observers, in different places, to mark these appearances, and to delineate the aspect of this planet during the space of two or three periodical revolutions,” marking the periods of the different changes, and noting at the same time the positions of his satellites—it might be ascertained, whether these changes are occasioned by tides, which are differently affected according to the position of his moons, or, by immense strata of clouds, or other changes that take place in his atmosphere, or by some great physical revolutions which are occasionally agitating the surface of this planet. The observers of such facts behooved to be numerous, in order

*The annual or periodical revulution of Jupiter is Completed in about eleven years and ten months.

that the deficiencies of one might be supplied by another, and the general conclusions deduced from a comparison of all the observations taken together; and it would be requisite, that the places of observation be in different countries, that the deficiency of observations in one place, occasioned by a cloudy atmosphere, might be compensated by those made in the serene sky of another. Such a series of observations, although they should not lead to satisfactory conclusions in relation to the particulars now stated, could scarcely fail of throwing some additional light on the nature and constitution of this planet. o

With respect to the planet Venus, the author some time ago ascertained from observation,i that this planet may be distinctly seen in the day-time, at the time of its superior conjunction with the sun, when it presents to the earth a full enlightened hemisphere; provided its geocentric latitude, or distance from the sun's centre at the time be not less than 1943/. This is the only position (except at the time of a transit, which happens only once or twice in a

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