Remembering these facts, you will, I think, look at the heavens with a new interest.  There is a bright star, Vega, or Alpha Lyrae, a beautiful gem, so far off that the light from it which now reaches our eyes started before many of my audience were born.  Suppose that there are astronomers residing on worlds amid the stars, and that they have sufficiently powerful telescopes to view this globe, what do you think they would observe?  They will not see our earth as it is at present; they will see it as it was years (and sometimes many years) ago.  There are stars from which if England could now be seen, the whole of the country would be observed at this present moment to be in a great state of excitement at a very auspicious event.  Distant astronomers might notice a great procession in London, and they could watch the coronation of a youthful queen amid the enthusiasm of a nation.  There are other stars still further, from which, if the inhabitants had good enough telescopes, they would now see a mighty battle in progress not far from Brussels.  One splendid army could be beheld hurling itself time after time against the immovable ranks of the other.  They would not, indeed, be able to hear the ever-memorable “Up, Guards, and at them!” but there can be no doubt that there are stars so far away that the rays of light which started from the earth on the day of the battle of Waterloo are only just arriving there.  Further off still, there are stars from which a bird’s-eye view could be taken at this very moment of the signing of Magna Charta.  There are even stars from which England, if it could be seen at all, would now appear, not as the great England we know, but as a country covered by dense forests, and inhabited by painted savages, who waged incessant war with wild beasts that roamed through the island.  The geological problems that now puzzle us would be quickly solved could we only go far enough into space and had we only powerful enough telescopes.  We should then be able to view our earth through the successive epochs of past geological time; we should be actually able to see those great animals whose fossil remains are treasured in our museums tramping about over the earth’s surface, splashing across its swamps, or swimming with broad flippers through its oceans.  Indeed, if we could view our own earth reflected from mirrors in the stars, we might still see Moses crossing the Red Sea, or Adam and Eve being expelled from Eden.

So important is the subject of star distance that I am tempted to give one more illustration in order to bring before you some conception of how vast such distances are.  I shall take, as before, the nearest of the stars so far as known to us, and I hope to be forgiven for taking an illustration of a practical and a commercial kind instead of one more purely scientific.  I shall suppose that a railway is about to be made from London to Alpha Centauri.  The length of that railway, of course, we have already stated:  it