text:  The discovery of those mute records of past changes which lay buried in the earth has induced us to investigate with awakened curiosity those changes which are actually taking place before us in the broad day and in our own generation; and the result has been a conviction that in the activity of nature there was a provision made not only for restoration from decay and a perpetual renewal of the individuals of each species but for successive transformations in the surface of the globe fitting it for successive forms of vegetable and animal life