The Pamphlet Collection of Sir Robert Stout: Volume 29
Tracks of the Brontozoum
Tracks of the Brontozoum.
You will all see that singular series of tracks which is copied to its natural size in the large diagram hanging up here, which I owe to the kindness of my friend Professor Marsh, with whom I had the opportunity recently of visiting the precise locality in Massachusetts in which these tracks occur. I am, therefore, able to give you my own testimony, if needed, that they accurately represent the state of things which we saw. The valley of the Connecticut is classical ground for the geologist. It contains great beds of sandstone, covering many square miles, and which present this peculiarity, that they have evidently formed a part of an ancient sea shore, or, it may be, lake shore, and that they have been sufficiently soft for a certain period of time to receive the impressions of whatever animals walked over them, and to preserve them afterward in exactly the same way as such impressions are at this very moment preserved on the shores of the Bay of Fundy and elsewhere. We have there the tracks of some gigantic animal (pointing to the diagram) which walked on its hind legs. You see the series of marks made alternately by the right foot and by the left foot; so that from one impression to the other of the three-toed feet on the same side is one stride, and that stride, as we measured it, is six feet nine inches. I leave you, therefore, to page 21 form an impression of the magnitude of the creature which must have walked along the ancient shore, and which made these impressions.
Now, of such impressions there are untold thousands upon these shores. Fifty or sixty different kinds have been discovered, and they cover vast areas. But up to this present time not a bone, not a fragment, of any one of the great creatures which certainly made these impressions has been found; and the only skeleton which has been met with in all these deposits to the present day, though they have been carefully hunted over, is one fragmentary skeleton of one of the smaller forms. What has become of all these bones? You see we are not dealing with little creatures, but animals that make a step of six feet nine inches; and their remains must have been left somewhere. The probability is that they have been dissolved away, and absolutely lost.
I have had occasion to work at series of fossil remains of which there was nothing whatever except the casts of the bones, the solid material of the bone having been dissolved out by percolating water. It was a chance in this case that the sandstone happened to be of such a constitution as to set, and to allow the bones to be afterward dissolved out.
Had that constitution been other than what it was, the bones would have been dissolved, the beds of sandstone would have fallen together, become one mass, and not the slightest indication that the animal had existed would have been discovered.
I know of no more striking evidence than this fact affords from which it may be concluded, in the absence of organic remains, that such animals did exist. I believe that having the right understanding of the doctrine of Evolution on the one hand, and having a just estimation of the importance of the imperfection of the geological record on the other, would remove all difficulty from the kind of evidence to which I have thus adverted, and this appreciation allows us to believe that all such cases are examples of what I may here call, and have hitherto designated, negative or indifferent evidence—that is to say, they in no way directly advance the theory of Evolution, but they are no obstacle in the way of our belief in the doctrine.