Our website is made possible by displaying online advertisements to our visitors.
Please consider supporting us by disabling your ad blocker.

Download links will be available after you disable the ad blocker and reload the page.
Showing: 1-10 results of 127

PREFACE. This work was originally written to be delivered as a lecture; but as its pages continued to multiply, it was suggested to the author by numerous friends that it ought to be published in book-form; this, at last, the author concluded to do. This work, therefore, does not claim to be an exhaustive discussion of the various departments of which it treats; but rather it has been the aim of the author to present the more interesting... more...

TWO NEW INSTITUTIONS OF SCIENCE; ANDTHE SCENES WHICH ATTENDED THEIR CHRISTENING. In the month of August last, two events took place in the city of Albany, which have more than an ephemeral interest. They occurred in close connection with the proceedings of a Scientific Convention, and the memory of them deserves to be cherished as a recollection of the easy way in which Science may be popularized and be rendered so generally acceptable that the... more...

CHAPTER I. THE ASTRONOMICAL OBSERVATORY. Early Astronomical Observations—The Observatory of Tycho Brahe—The Pupil of the Eye—Vision of Faint Objects—The Telescope—The Object-Glass—Advantages of Large Telescopes—The Equatorial—The Observatory—The Power of a Telescope—Reflecting Telescopes—Lord Rosse's Great Reflector at Parsonstown—How the mighty Telescope is... more...

I THE BREATH OF LIFE I When for the third or fourth time during the spring or summer I take my hoe and go out and cut off the heads of the lusty burdocks that send out their broad leaves along the edge of my garden or lawn, I often ask myself, "What is this thing that is so hard to scotch here in the grass?" I decapitate it time after time and yet it forthwith gets itself another head. We call it burdock, but what is burdock, and why does it... more...

It is very easy to gain a knowledge of the stars, if the learner sets to work in the proper manner. But he commonly meets with a difficulty at the outset of his task. He provides himself with a set of the ordinary star-maps, and then finds himself at a loss how to make use of them. Such maps tell him nothing of the position of the constellations on the sky. If he happen to recognize a constellation, then indeed his maps, if properly constructed,... 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...

PREFACE The object of this book is to give an account of the science of Astronomy, as it is known at the present day, in a manner acceptable to the general reader. It is too often supposed that it is impossible to acquire any useful knowledge of Astronomy without much laborious study, and without adventuring into quite a new world of thought. The reasoning applied to the study of the celestial orbs is, however, of no different order from that... 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...

WHAT IS DARWINISM? This is a question which needs an answer. Great confusion and diversity of opinion prevail as to the real views of the man whose writings have agitated the whole world, scientific and religious. If a man says he is a Darwinian, many understand him to avow himself virtually an atheist; while another understands him as saying that he adopts some harmless form of the doctrine of evolution. This is a great evil. It is obviously... more...