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Showing: 41-50 results of 127

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...

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...

Some thousands of years ago there was a city in Mesopotamia called Surippak. One night a strange dream came to a dweller therein, whose name, if rightly reported, was Hasisadra. The dream foretold the speedy coming of a great flood; and it warned Hasisadra to lose no time in building a ship, in which, when notice was given, he, his family and friends, with their domestic animals and a collection of wild creatures and seed of plants of the land,... more...

CHAPTER I. EARLY OBSERVERS OF MARS. Few persons except astronomers fully realise that of all the planets of the Solar system the only one whose solid surface has been seen with certainty is Mars; and, very fortunately, that is also the only one which is sufficiently near to us for the physical features of the surface to be determined with any accuracy, even if we could see it in the other planets. Of Venus we probably see only the upper surface... more...

ON THE ADVISABLENESS OF IMPROVING NATURAL KNOWLEDGE. This time two hundred years ago—in the beginning of January, 1666—those of our forefathers who inhabited this great and ancient city, took breath between the shocks of two fearful calamities, one not quite past, although its fury had abated; the other to come. Within a few yards of the very spot on which we are assembled, so the tradition runs, that painful and deadly malady, the... more...


When it was my duty to consider what subject I would select for the six lectures* ([Footnote] *To Working Men, at the Museum of Practical Geology, 1863.) which I shall now have the pleasure of delivering to you, it occurred to me that I could not do better than endeavour to put before you in a true light, or in what I might perhaps with more modesty call, that which I conceive myself to be the true light, the position of a book which has been... more...

I. THE THREE HYPOTHESES RESPECTING THE HISTORY OF NATURE We live in and form part of a system of things of immense diversity and perplexity, which we call Nature; and it is a matter of the deepest interest to all of us that we should form just conceptions of the constitution of that system and of its past history. With relation to this universe, man is, in extent, little more than a mathematical point; in duration but a fleeting shadow; he is a... more...

COAL AND COAL-MINES. There are few subjects of more importance, and few less known or thought about, than our coal-mines. Coal is one of our greatest blessings, and certainly one originating cause of England's greatness and wealth. It has given us a power over other nations, and vast sums of money are yearly brought to our country from abroad in exchange for the coal we send. Nearly £17,000,000 is the representative value of the coal... more...

CHAPTER I.APPARENT ATTRIBUTES OF THE STARS. 1. Our knowledge of the stars is based on their apparent attributes, obtained from the astronomical observations. The object of astronomy is to deduce herefrom the real or absolute attributes of the stars, which are their position in space, their movement, and their physical nature. The apparent attributes of the stars are studied by the aid of their radiation. The characteristics of this radiation... more...

In the two preceding lectures I have endeavoured to indicate to you the extent of the subject-matter of the inquiry upon which we are engaged; and now, having thus acquired some conception of the Past and Present phenomena of Organic Nature, I must now turn to that which constitutes the great problem which we have set before ourselves;—I mean, the question of what knowledge we have of the causes of these phenomena of organic nature, and how... more...