PREFACE. THE plan and outlines of the following work were sketched, and a considerable portion of it composed, about eighteen years ago. It was advertised, as preparing for the press, in 1823, when the author published the first edition of "The Christian Philosopher;" but various other engagements prevented its appearance at that period. The Introduction and the first two sections were published in a respectable quarterly journal in the year 1816; but they are now considerably modified and enlarged. This circumstance will account for the date of some of the illustrative facts to which reference is made in the first part of the volume, and in several portions of the Appendix. Had the present work been published at any of the periods now referred to, the subject it discusses, and some of the illustrations, would have presented a more novel aspect than they can lay claim to at the present time, when the diffusion of knowledge has become an object of general attention. The author, however, is not aware that any work embracing so full an illustration of the same topics has yet made its appearance; and is, therefore, disposed to indulge the hope, that, in conjunction with the present movements of society, it may, in some degree, tend to stimulate those exertions which are now making for the melioration and mental improvement of mankind. Independently of the general bearing of the facts and illustrations on the several topics they are intended to elucidate, the author trusts that not a few fragments of useful knowledge will be found incorporated in the following pages, calculated to entertain and instruct the general reader. In the numerous illustrations brought forward in this volume, it was found impossible altogether to avoid a recurrence to certain facts which the author had partially adverted to in some of his former publications, without interrupting the train of thought, and rendering his illustrations partial and incomplete. But, where the same facts are introduced, they are generally brought forward to elucidate a different topic. Any statements or descriptions of this kind, however, which may have the appearance of repetition, could all be comprised within the compass of three or four pages. The general subject of the present work will be prosecuted in another volume, to be entitled "The Mental Illumination of Mankind, or an inquiry into the means by which a general diffusion of knowledge may be promoted." This work will embrace-along with a great variety of other topics-an examination of the present system of education, showing its futility and inefficiency, and illustrating the principles and details of an efficient intellectual system onable of universal application; together with a variety of suggestions in the physical, moral, and intellectual improvement of society. To his numerous correspondents who have been inquiring afte "The Scenery of the Heavens Displayed, with the view of illustrating of a Plurality of Worlds," which was announced at page 88 of the of a Future State," the author begs respectfully to state, that, if alth permit, he intends to proceed, without delay, to the completion of that work, as soon as the volume announced above is ready for the press. It will form a volume of considerable size, and will be illustrated with a great number of engravings, many of which will be original. Broughty Ferry, near Dundee, 18th April, 1833. CONTENTS. Page Introduction-Retrospective view of the state of mankind-ignorance of the dark ages— revival of learning at the Reformation. Present intellectual state of the human race. Causes which have retarded the progress of the human mind. A more general diffusion of knowledge desirable. Preludes which indicate the approach of the era of intelligence 11 Objects and circumstances which ignorance has arrayed with imaginary terrors-eclipses, 17 Accidents which have happened from ignorance of the properties of the different gases, and the means of preventing them. Disasters which have happened in coal mines. Figure of Davy's Safety Lamp, with description and remarks. Accidents caused by the stroke of lightning. Precautions requisite to be attended to during thunder-storms. Accidents from ignorance of the principles of mechanics. Reasons of such accidents explained by a figure. Fatal accidents caused from ignorance of the effects produced by the refraction of light-illustrated by figures and experiments. Accidents from the clothes of females catching fire, and the means of prevention. Various diseases propagated from ignorance of their nature. Pernicious effects of contaminated air. Improper mode of treating children during infancy, and its fatal effects. Importance of temperance. General Science founded on facts. Every person is endowed with faculties for observing facts. be nearly in proportion to the number of observers. Various illustrations of these positions. Geology, its multifarious objects and desiderata. Natural History, how it may be improved, and its range extended. Meteorology, imperfection of our knowledge in regard to many of its objects,-thunder-storms, aurora borealis, meteoric stones, &c. Astronomy, deside- rata in reference to, which remain to be ascertained. Illustration taken from Jupiter, with four different views of this planet. Venus, mode by which the time of its rotation may be determined-illustrated by a figure. Comets, fixed stars.-Moon, plan by which our knowledge of the scenery of this globe may be extended. Discoveries which have been made in the heavens by accident. Prospects presented when knowledge shall be more generally diffused. Chymistry, its objects, and the means of its improvement. Futility of framing hypotheses-importance of observing facts-general remarks and ON THE PLEASURES CONNECTED WITH THE PURSUITS OF SCIENCE. Pleasures of sense and of intellect. The enjoyments of the ignorant and of the man of presents before us. Variety of novel and interesting objects it exhibits. Illustrated from mechanics, hydrostatics, magnetism, optics, chymistry, &c. Instruments connected with optics. Figure of the Aerial Telescope. Pleasure in tracing the steps by which dis- coveries have been made, and the experiments by which they are illustrated. Beneficial tendency of scientific pursuits on the heart, and on social and domestic enjoyment. Mis- ON THE PRACTICAL INFLUENCE OF SCIENTIFIC KNOWLEDGE, AND ITS TENDENCY I. A knowledge of science would render mechanics, &c. more skilful in their respectiv employments-illustrated from the arts of dying, calico printing, bleaching, brewing, tanning, agriculture, &c. Chymistry essentially requisite to surgeons and apothecaries. Utility of practical Geometry, illustrated by a diagram. Utility of Mechanics. Of Hydro- statics and Hydraulics, illustrated with various figures. Hydrostatical paradox, mode of conveying water, hydrostatical press, perpendicular pressure of water, and the accidents it may occasion. Application of these facts to engineering and hydraulic operations. Disaster occasioned by want of attention to hydrostatic principles. Practical utility of Pneumatics anecdote illustrative of. Mode of curing smoky chimneys, illustrated by figures. Utility of an acquaintauce with Optics. Explanation of the nature of a telescope, and the mode of its construction. Mode of constructing a compound microscope, with illustrative figures. Burning lenses, Sir D. Brewster's Polyzonal Lens, reflecting concave mirrors for light-houses, &c., with illustrative figures. Utility of Electricity and Galvanism. Mode of directing lightning as a mechanical power. Practical applications of Magnetism, and late discoveries in-Magnetized masks, &c. Practical utility of Geology. Utility of Natural History. Application of steam-steam navigation-steam carriages. Carburetted hydrogen gas. Utility of science to day- labourers, house-keepers, kitchen-maids, &c. Instance illustrative of the advantages II. Scientific knowledge would pave the way for future inventions and improvements in the arts, |