Page:World of Wonders, The (1873?, Cassell, Petler, and Galpin).djvu/18

 the time of the birth of Moses, or nearly four thousand years ago, he would as yet have accomplished only half his journey!"

The sun, which so many have worshipped, and which is, humanly speaking, the source of life to us all, is another perpetual wonder. Its circumference is about 2,770,000 miles. Its distance from the earth is so great that a railway train moving at 32 miles per hour would take three millions of hours, or three hundred and forty-two years and three months, to travel from London to the sun, supposing that it could travel incessantly night and day during that time. A cannon-ball, moving fifty times faster than such a train, would expend seven years in reaching it. To make a globe like the sun, it would take 1,400,000 globes like the earth rolled into one! Or, to make these facts simpler, and yet more stupendous, the bulk of the sun is five hundred times greater than the aggregate bulk of all the other bodies of the solar system of which night only reveals to us a small part—that which appears above our hemisphere, and above our particular stand-point. The centre of the sun is a dark mass covered with a garment of flame. But in this luminous matter there are vast rents. We talk of spots in the sun; spots indeed! the space occupied or laid bare by the principal spot is 928,000,000 square geographical miles. Arago, by a physical test, proved that this garment of flame, this luminous matter, must be gaseous; so that the sun floats in an ocean of flame, and this is so powerful that the strongest blast furnace yet ignited by man, at its highest power, is seven 'times weaker than the sun's heat at its surface. If the heat be electric, how great is the wonder! How is this electricity maintained, if, according to a later theory, the heat is derived from perpetual combustion of matter flying into the sun as coal is projected on a furnace? What millions of tons must every year be consumed!—the heat being dispersed over space so great that the earth's surface, at a distance of 95,000,000 miles, notwithstanding the alternation of night, receives in a year sufficient, if uniformly diffused, to liquefy a crust of ice 100 feet in thickness.

But if we confine ourselves to the wonders of this world, and do not soar to the three thousand worlds in the sky visible to the naked eye, nor to the fifty thousand stars "that passed," says Sir William Herschel, "over a field of view two degrees of breadth in a single hour," we shall have enough to do, and what we are about to endeavour we have, perhaps, sufficiently indicated to the reader. In all cases we shall give as far as possible the authorities on which our statements are based, though for the credibility of the facts related we cannot of course undertake to be responsible. The purely scientific wonders will be treated of by writers of eminence in their respective spheres.

How true it is that familiarity with the strange and marvellous soon reduces it to the level of the uninteresting and commonplace! Only come in contact every day with a phenomenon which at first excited our attention and aroused our wonder, and we soon cease to be astonished; in time the oft-repeated experiment, or oft-observed phenomenon, does not even attract our attention, and no longer causes us to halt in our path to ask Why? or even to satisfy our unquestioning curiosity.

We all know what a magnet is; dozens of the little red horseshoes hang side by side in the window of every scientific shopman. The eye is attracted by their bright colouring, but one sees at once they are only magnets; perhaps we notice the price, and may think sixpence cheap or dear, but there the thought ends. Is it that magnets are not worth thinking about? or is it that there is nothing after all so very curious or mysterious about them—they are well understood, and we have possessed ourselves of their whole history and relations? No! one passes on unattracted, because we have seen hundreds of magnets, and long familiarity with the phenomenon of magnetism has caused us to cease wondering. 'The writer remembers once a youth, from the depths of the country, coming into his laboratory. A magnet was lying on the table, he took it up, and touched the armature—the bright piece of iron at the end—which moved backwards and forwards as though it were a hinge; and yet, when he was told to use a little force, he could pull the armature completely off. His astonishment was unbounded; again and again he returned to the magnet, and the magic influence under which the armature seemed to come, upon approaching the horse-shoe, had for him a greater charm than anything else which was shown to him. Familiarity had not rendered him incapable of being wonder-struck with what is truly a wonderful phenomenon,

All attraction is wonderful. Why should a stone fall to the ground when not supported? The answer that the earth attracts it only expresses the fact, it by no means explains it; and to say that it is the nature of things to exercise an attractive influence upon each other is no further resolution of the difficulty.

We are able to take one step nearer to the answer— Why does a magnet attract a nail?—but that step only shows us a greater wonder, and leaves us more mystified than ever. But to produce wonder is the object of this paper.

If a person, with an ordinary horse-shoe magnet, tested all substances within his reach, he would find the magnet would attract none save iron. Experiments more delicately conducted have, however, shown, that there are four other elements slightly