Under meteorological laws I include all atmospheric phenomena. And although we have no direct proof from geology in respect to the more rare of these phenomena, such as the aurora borealis and australis, and transient meteors, yet in respect to the existence of clouds, wind, and rain, the evidence is quite striking. In several places in Europe, and in many in this country, are found, upon layers of the new red sandstone, the distinct impressions of rain drops, made when the rock was fine mud. They correspond precisely with the indentations which falling rain-drops now make upon mud, and they show us that the phenomena of clouds and storms existed in that remote period, and that the vapor was condensed as at present. In the fact that the animals entombed in the rocks of various ages are found to have had organs of respiration, we also infer the existence of an atmosphere analogous to that which we now breathe. The rain-drops enable us to proceed one step farther; for often they are elongated in one direction, showing that they struck the ground obliquely, doubtless in consequence of wind. In short, the facts stated enable us to infer, with strong probability, that atmospheric phenomena were then essentially the same as at present; and analogy leads us to a similar conclusion as to all the past periods of the world's history, certainly since animals were placed upon it. What a curious register do these rain-drops present us! an engraving on stone of a shower that fell thousands and thousands of ages ago! They often become, too, an anemoscope, pointing out the direction of the wind, while the petrified surface shows us just how many drops fell, quite as accurately as the most delicate pluviameter. What events in the earth's pre-Adamic history would seem less likely to come down to us than the pattering of a shower? _In the third place, the agents of geological change appear to have been always the same on the earth._