We now find about us tree-ferns, club-mosses, reeds, calamites, lichens. There are fishes swarming in the warm seas; a few insects and spiders crawl among the ferns; here and there are toads, newts, and scorpions of curious patterns. One, two, three, four, five ages back we wander, and now the mosses and pines, the fishes and reptiles have disappeared, and we are in the age of sea-weeds and corals, crabs and mollusks, such as have few types in the modern world. And here, in the lower-Silurian, we have arrived at our ancient burial-ground. Have we not come a long way to find it? Is there no shorter way to reach it? We have come here by the every-day style of a carriage over a few miles of plain and hill. We have come here also by a dash in imagination through three great times and thirteen busy ages of world-building. We can take yet a third way. Go yonder to the valley and sink a shaft for seven hundred feet, and you will pass through these ages and times and reach the era of this burial-ground. There it is hidden seven hundred feet deep; here it crops out into the sunshine; here have been tumult and convulsion, and what in some places might be thousands of feet below the surface, is here thrust up among modern methods, among apple trees, and bleating sheep, and white cottages, and little children at their play. There is still another method of reaching this same burial-ground. Go into the valley and wander five miles toward the mouth of the little creek that divides it. As you touch its grassy bank you stand in the modern age of the present earth-building time. As you travel down the creek, the successive beds or stages of earth-building are laid bare, one after another, until at the end of five miles you stand on the lower-Silurian stratum of this burial-ground. Take a pamphlet, fold the first leaf over one half, the next a little less, and so on for thirteen pages, and you have a pattern of the manner in which the spring and autumn torrents flushing the brook have laid bare the rock strata, and shown them as they lie here closely crowded upon each other. This is, however, an unusual case, for each of these ages has in many places left deposits thousands of feet in thickness. Here the uncovering has been rapid, deposit light, and we can turn over the geologic pages in a volume a few hundreds of feet thick.