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Showing: 41-50 results of 127

PREFATORY NOTE. In complying with the wish of the publishers of Professor Haeckel's reply to Professor Virchow, that I should furnish a prefatory note expressing my own opinion in respect of the subject-matter of the controversy, Gay's homely lines, prophetic of the fate of those "who in quarrels interpose," emerge from some brain-cupboard in which they have been hidden since my childish days. In fact, the hard-hitting with which both the attack... more...

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...

MERCHANTS occasionally go through a wholesome, though troublesome and not always satisfactory, process which they term "taking stock." After all the excitement of speculation, the pleasure of gain, and the pain of loss, the trader makes up his mind to face facts and to learn the exact quantity and quality of his solid and reliable possessions. The man of science does well sometimes to imitate this procedure; and, forgetting for the time the... 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...

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...