Page:Popular Astronomy - Airy - 1881.djvu/108

94 which Mars revolves as at Ma, carried by an arm so long that it projects beyond the earth, so that its orbit completely surrounds the earth, as well as the sun, in describing its whole motion.

It is, however, rather difficult for us to conceive how the centre of this motion can be carried. There is no bar that we can see. It was, however, necessary for them to suppose that there is a bar which is attached at one end to the earth, and which carries the sun, and carries also the centres of the motion of the other planets. It does appear strange that any reasonable man could entertain such a theory as this. It is, however certain that they did entertain such a notion; and there is one thing which seems to me to give something of a clue to it: in speaking to-day and yesterday of the faults of education, I said that we take things for granted without evidence; mankind in general adopt things instilled into them in early youth as truths, without sufficient examination; and I now add that philosophers are much influenced by the common belief of the common people. There is one passage in Herodotus, where he is endeavouring to account for certain phenomena in Egypt, which I have often read, and which, so far as I can see, can only mean this: "That certain periodical winds do carry the sun from north to south, and that thus the change of seasons is produced." I think it likely that Herodotus (who was a learned man for that time) believed that the sun was something in the atmosphere little better than a cloud, perhaps not so important as an aurora borealis, and that it might be carried along by the winds. We know, also, that at a time not very distant from that, a Greek philosopher, named Anaxagoras, dissented from this notion, saying—"That the sun was solid, and as big as