It has often been said, not untruly, that merely negative arguments have little permanent influence over the opinions of men, and that institutions which have been temporarily overthrown by negation will shortly be set up again, and flourish in their old vigor, unless something positive can be found to supply their place. But here is a doctrine of a most positive kind. "The order of nature is invariably according to regular sequences." It is a doctrine which cannot be proved, for we cannot follow all the changes which have ever taken place in the universe; but, although incapable of demonstration, it may be accepted until something happens to disprove it; and it _is_ accepted, with the most absolute faith, by a constantly increasing number of adherents. To show how this doctrine acts in diminishing religious emotion by taking away the opportunity for it, let me narrate an incident which really occurred on a French line of railway in the winter of 1882. The line, on which I had travelled a few days before, passes between a river and a hill. The river has a rocky bed and is torrential in winter; the hill is densely covered with a pine forest coming down to the side of the line. The year 1882 had been the rainiest known in France for two centuries, and the roots of the trees on the edge of this pine forest had been much loosened by the rain. In consequence of this, two large pine-trees fell across the railway early one morning, and soon afterwards a train approached the spot by the dim light of early dawn. There was a curve just before the engine reached the trees, and it had come rapidly for several miles down a decline. The driver reversed his steam, the engine and tender leaped over the trees, and then went over the embankment to a place within six feet of the rapid river. The carriages remained on the line, but were much broken. Nobody was killed; nobody was seriously injured. The remarkable escape of the passengers was accounted for as follows by the religious people in the neighborhood. There happened to be a priest in the train, and at the time when the shock took place he made what is called "a pious ejaculation." This, it was said, had saved the lives of the passengers. In the ages of faith this explanation would have been received without question; but the notion of natural sequences--Professor Huxley's "order with which nothing interferes"--had obtained such firm hold on the minds of the townsmen generally that they said the priest was trying to make ecclesiastical capital out of an occurrence easily explicable by natural causes. They saw nothing supernatural either in the production of the accident or its comparative harmlessness. The trickling of much water had denuded the roots of the trees, which fell because they could not stand with insufficient roothold; the lives of the passengers were saved because they did not happen to be in the most shattered carriage; and the