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Showing: 1-10 results of 127

CHAPTER I HEAT I. Value of Fire. Every day, uncontrolled fire wipes out human lives and destroys vast amounts of property; every day, fire, controlled and regulated in stove and furnace, cooks our food and warms our houses. Fire melts ore and allows of the forging of iron, as in the blacksmith's shop, and of the fashioning of innumerable objects serviceable to man. Heated boilers change water into the steam which drives our engines on land and... more...

ASTROLOGY. Signs and planets, in aspects sextile, quartile, trine, conjoined, or opposite; houses of heaven, with their cusps, hours, and minutes; Almuten, Almochoden, Anahibazon, Catahibazon; a thousand terms of equal sound and significance.—Guy Mannering. ... Come and see! trust thine own eyes.A fearful sign stands in the house of life,An enemy: a fiend lurks close behindThe radiance of thy planet—oh! be warned!—Coleridge.... more...

CHAPTER I. A HALF-HOUR ON THE STRUCTURE OF THE TELESCOPE. There are few instruments which yield more pleasure and instruction than the Telescope. Even a small telescope—only an inch and a half or two inches, perhaps, in aperture—will serve to supply profitable amusement to those who know how to apply its powers. I have often seen with pleasure the surprise with which the performance even of an opera-glass, well steadied, and... more...

PART I Good sense is, of all things among men, the most equally distributed; for every one thinks himself so abundantly provided with it, that those even who are the most difficult to satisfy in everything else, do not usually desire a larger measure of this quality than they already possess. And in this it is not likely that all are mistaken the conviction is rather to be held as testifying that the power of judging aright and of distinguishing... more...

INTRODUCTION The Science of Astronomy is sublime and beautiful. Noble, elevating, consoling, divine, it gives us wings, and bears us through Infinitude. In these ethereal regions all is pure, luminous, and splendid. Dreams of the Ideal, even of the Inaccessible, weave their subtle spells upon us. The imagination soars aloft, and aspires to the sources of Eternal Beauty. What greater delight can be conceived, on a fine spring evening, at the... more...


PREFACE In offering this book to teachers of elementary chemistry the authors lay no claim to any great originality. It has been their aim to prepare a text-book constructed along lines which have become recognized as best suited to an elementary treatment of the subject. At the same time they have made a consistent effort to make the text clear in outline, simple in style and language, conservatively modern in point of view, and thoroughly... more...

THE DIAGRAMS. The diagrams, it will be observed, are grouped under the seasons, and they indicate the positions of the constellations as they appear at 9 o'clock p.m. in mid-season. To facilitate finding and observing the constellations, the student should face in the direction indicated in the text. This applies to all constellations excepting those near the zenith. The four large plates are so arranged that the observer is supposed to be... more...

CHAPTER I ON RAYS PROPAGATED IN STRAIGHT LINES   s happens in all the sciences in which Geometry is applied to matter, the demonstrations concerning Optics are founded on truths drawn from experience. Such are that the rays of light are propagated in straight lines; that the angles of reflexion and of incidence are equal; and that in refraction the ray is bent according to the law of sines, now so well known, and which is no less certain... more...

CHAPTER I THE PROBLEM: THE MODE OF ITS SOLUTION The story of a human life can be told in very few words. A youth of golden dreams and visions; a few years of struggle or of neglected opportunities; then retrospect and the end. "We come like water, and like wind we go." But how few of the visions are realized. Faust sums up the whole of life in the twice-repeated word versagen, renounce, and history tells a similar story. Terah died in Haran;... more...

That application of the sciences of biology and geology, which is commonly known as palaeontology, took its origin in the mind of the first person who, finding something like a shell, or a bone, naturally imbedded in gravel or rock, indulged in speculations upon the nature of this thing which he had dug out—this "fossil"—and upon the causes which had brought it into such a position. In this rudimentary form, a high antiquity may... more...