The object is to keep all the fragments and splinters of bone together until it can reach the skilful hands of the museum preparator.
_The Rock Waves Connecting the Bluffs and the Quarry._ The Como Bluffs are about ten miles south of the Bone-Cabin Quarry; between them is a broad stretch of the Laramie Plains.

The exposed bone layer in the two localities is of the same age, and originally was a continuous level stratum which may be designated as the "dinosaur beds;" but this stratum, disturbed and crowded by the uplifting of the not far-distant Laramie range of mountains and the Freeze Out Hills, was thrown into a number of great folds or rock waves.

Large portions, especially of the upfolds, or "anticlines," of the waves, have been subsequently removed by erosion; the edges of these upfolds have been exposed, thus weathering out their fossilized contents, while downfolds are still buried beneath the earth for the explorers of coming centuries.
Therefore, as one rides across the country to-day from the bluffs to the quarry, startling the intensely modern fauna, the prong-horn antelopes, jack-rabbits, and sage-chickens, he is passing over a vast graveyard which has been profoundly folded and otherwise shaken up and disturbed.

Sometimes one finds the bone layer removed entirely, sometimes horizontal, sometimes oblique, and again dipping directly into the heart of the earth.

This layer (dinosaur beds) is not more than two hundred and seventy-four feet in thickness, and is altogether of fresh-water origin; but as a proof of the oscillations of the earth-level both before and after this great thin sheet of fresh-water rock was so widely spread, there are evidences of the previous invasion of the sea (ichthyosaur beds) and of the subsequent invasion of the sea (mosasaur beds) in the whole Rocky Mountain region.
In traveling through the West, when once one has grasped the idea of continental oscillation, or submergence and emergence of the land, of the sequence of the marine and fresh-water deposits in laying down these pages of earth-history, he will know exactly where to look for this wonderful layer-bed of the giant dinosaurs; he will find that, owing to the uplift of various mountain-ranges, it outcrops along the entire eastern face of the Rockies, around the Black Hills, and in all parts of the Laramie Plains; it yields dinosaur bones everywhere, but by no means so profusely or so perfectly as in the two famous localities we are describing.
_How the Skeletons Lie in the Bluffs and Quarry._ At the bluffs single animals lie from twenty to one hundred feet apart; one rarely finds a whole skeleton, such as that of Marsh's _Brontosaurus excelsus_, the finest specimen ever secured here, which is now one of the treasures of the Yale museum.