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Showing: 11-20 results of 127

THE FUTURE OF ASTRONOMY BY PROFESSOR EDWARD C. PICKERING HARVARD COLLEGE OBSERVATORY It is claimed by astronomers that their science is not only the oldest, but that it is the most highly developed of the sciences. Indeed it should be so, since no other science has ever received such support from royalty, from the state and from the private individual. However this may be, there is no doubt that in recent years astronomers have had granted to... more...

PREFACE The contents of this book were originally delivered at Trinity College in the autumn of 1919 as the inaugural course of Tarner lectures. The Tarner lectureship is an occasional office founded by the liberality of Mr Edward Tarner. The duty of each of the successive holders of the post will be to deliver a course on ‘the Philosophy of the Sciences and the Relations or Want of Relations between the different Departments of... more...

Hoffman, in one of his observations, gives the history of a powder called magnesia alba, which had long been used and esteemed as a mild and tasteless purgative; but the method of preparing it was not generally known before he made it public. It was originally obtained from a liquor called the mother of nitre, which is produced in the following manner: Salt-petre is separated from the brine which first affords it, or from the water with which... more...

PART I THE SPECIAL THEORY OF RELATIVITY PHYSICAL MEANING OF GEOMETRICAL PROPOSITIONS In your schooldays most of you who read this book made acquaintance with the noble building of Euclid's geometry, and you remember — perhaps with more respect than love — the magnificent structure, on the lofty staircase of which you were chased about for uncounted hours by conscientious teachers. By reason of our past experience, you would... more...

The study of the History of Chemistry as an art, or as a science, is one which possesses peculiar fascination for its votaries. It has been the subject of deep research and much discussion, much has been written upon the subject, and many theories have been broached to account for its origin. We have had laid before us by Professor Ferguson, in his papers on this subject of Chemical History, very clearly and fully the generally-accepted position... more...


CHAPTER I. INTRODUCTORY. The Sun. The sun's position in the great field of energy is daily becoming more exalted in the estimation of philosophic minds. His labors are being revealed to us with a distinctness never before conceived. He it is that stored the coal in the bosom of the earth, and piled up the polar ice. He it is that aids the chemist, drives the engine, ripens the harvest, dispenses life and health. The study of the sun and solar... more...

INTRODUCTION. That the phenomena of vegetation are dependent on certain chemical changes occurring in the plant, by which the various elements of its food are elaborated and converted into vegetable matter, was very early recognised by chemists; and long before the correct principles of that science were established, Van Helmont maintained that plants derived their nourishment from water, while Sir Kenelm Digby, Hook, Bradley, and others,... more...

WHAT ARE "SPECIES," AND WHAT IS MEANT BY THEIR "ORIGIN" Definition of species—Special creation—The early Transmutationists—Scientific opinion before Darwin—The problem before Darwin—The change of opinion effected by Darwin—The Darwinian theory—Proposed mode of treatment of the subject. The title of Mr. Darwin's great work is—On the Origin of Species by means of Natural Selection and the... more...

All knowledge is essentially one. The object-matter upon which intellect exerts itself, does not affect the subjective act of knowing. Physics, when stripped of that which is merely contingent, becomes metaphysics. Physical science deals with object-matter, and discusses the signs by which nature communicates her message—that is, phenomena. Metaphysical science has to do with the subject-mind, and discusses the meaning of the message. The... more...

INTRODUCTION We know, both by tradition and published records, that from the earliest times the faint grey and light spots which diversify the face of our satellite excited the wonder and stimulated the curiosity of mankind, giving rise to suppositions more or less crude and erroneous as to their actual nature and significance. It is true that Anaxagoras, five centuries before our era, and probably other philosophers preceding him,... more...