Now, Aristotle had said that bodies fell at rates depending on their weight. A five-pound weight would fall five times as quick as a one-pound weight; a fifty-pound weight fifty times as quick, and so on. Why he said so nobody knows. He cannot have tried. He was not above trying experiments, like his smaller disciples; but probably it never occurred to him to doubt the fact. It seems so natural that a heavy body should fall quicker than a light one; and perhaps he thought of a stone and a feather, and was satisfied. Galileo, however, asserted that the weight did not matter a bit; that everything fell at the same rate--even a stone and a feather, but for the resistance of the air--and would reach the ground in the same time. And he was not content to be pooh-poohed and snubbed. He knew he was right, and he was determined to make everyone see the facts as he saw them. So one morning, before the assembled university, he ascended the famous leaning tower, taking with him a one-hundred-pound shot and a one-pound shot. He balanced them on the edge of the tower, and let them drop together. Together they fell, and together they struck the ground. The simultaneous clang of those two weights sounded the death-knell of the old system of philosophy, and heralded the birth of the new. But was the change sudden? Were his opponents convinced? Not a jot. Though they had seen with their eyes and heard with their ears, the full light of heaven shining upon them, they went back muttering and discontented to their musty old volumes and their garrets, there to invent occult reasons for denying the validity of the observation, and for referring it to some unknown disturbing cause. They saw that if they gave way on this one point they would be letting go their anchorage, and henceforward would be liable to drift along with the tide, not knowing whither. They dared not do this. No; they _must_ cling to the old traditions; they could not cast away their rotting ropes and sail out on to the free ocean of God's truth in a spirit of fearless faith. Yet they had received a shock: as by a breath of fresh salt breeze and a dash of spray in their faces, they had been awakened out of their comfortable lethargy. They felt the approach of a new era. Yes, it was a shock, and they hated the young Galileo for giving it them--hated him with the sullen hatred of men who fight for a lost and dying cause.