_Tommy._--No, sir; I protest I have often thought that the houses and trees, and all the country, glided swiftly along by the windows of the coach. _Mr Barlow._--And did you never sail in a boat? _Tommy._--Yes, I have; and I protest I have observed the same thing; for I remember I have often thought the shore was running away from the boat, instead of the boat from the shore. _Mr Barlow._--If that is the case, it is possible, even though the earth should move, instead of the stars, that you might only see what you do at present, and imagine that the earth you are upon was at rest. _Tommy._--But is it not more likely that such little things as the stars and the sun should move, than such a large thing as the earth? _Mr Barlow._--And how do you know that the stars and sun are so small? _Tommy._--I see them to be so, sir. The stars are so small, that they are hardly to be seen at all; and the sun itself, which is much bigger, does not seem bigger than a small round table. The day after this conversation, as the weather was bright and clear, Mr Barlow went out to walk with Harry and Tommy. As by this time Tommy was inured to fatigue, and able to walk many miles, they continued their excursion over the hills, till at last they came in sight of the sea. As they were diverting themselves with the immense prospect of water that was before them, Mr Barlow perceived something floating at a distance, so small as to be scarcely discernible by the eye. He pointed it out to Tommy, who with some difficulty was able to distinguish it, and asked him what he thought it was. Tommy answered that he imagined it to be some little fishing-boat, but could not well tell, on account of the distance. _Mr Barlow._--If you do not then see a ship, what is it you do see? or what does that object appear to your eyes? _Tommy._--All that I can see is no more than a little dusky speck, which seems to grow bigger and bigger. _Mr Barlow._--And what is the reason it grows bigger and bigger? _Tommy._--Because it comes nearer and nearer to me. _Mr Barlow._--What, then, does the same thing sometimes appear small and sometimes great? _Tommy._--Yes, sir; it seems small when it is at a great distance; for I have observed even houses and churches when you are at some miles' distance, seem to the eye very small indeed; and now I observe that the vessel is sailing towards us, and it is not, as I imagined, a little fishing-boat, but a ship with a mast, for I begin to distinguish the sails. Mr Barlow walked on a little while by the side of the sea, and presently Tommy called out again: "I protest I was mistaken again; for it is not a vessel with one mast, as I thought a little while ago, but a fine large ship with three great masts, and all her sails before the wind. I believe she must either be a large merchantman or else a frigate."